MinTankesmie

Trigger marihuana ny vekst av hjerneceller?

Marijuana Compound Spurs Brain Cell Growth (Marihuana stimulerer cellevekst)
forbes.com 13.11.2005
-- When it comes to the controversy surrounding medical marijuana, an international team of researchers is busy stirring the pot by releasing findings that suggest the drug helps promote brain cell growth while treating mood disorders.

According to the study in rats, a super-potent synthetic version of the cannabinoid compound found in marijuana can reduce depression and anxiety when taken over an extended period of time.

This mood boost seems to be the result of the drug's ability to promote the growth of new brain cells, something no other addictive drug appears able to do, the researchers say.

The findings, which appear in the November issue of the Journal of Clinical Investigation, remain preliminary, however.

"Our results were obtained from rats, and there's a big difference between rats and humans," said study co-author Dr. Xia Zhang, of the neuropsychiatry research unit in the department of psychiatry at the University of Saskatchewan in Saskatoon, Canada. "So, I don't really don't know yet if our findings apply to humans. But our results indicate that the clinical use of marijuana could make people feel better by helping control anxiety and depression."

The new findings come on the heels of a U.S. Supreme Court ruling in June granting federal authorities the power to stop doctors from prescribing marijuana. That decision also bars individuals from cultivating the herb for medical purposes. (...)

(Anm: How Anti-Depressants Create New Brain Cells. medicalnewstoday.com 12.3.2007.)

(Anm: Primum non nocere (først, gjør ikke skade): evolusjonær analyse av hvorvidt antidepressiva gjør mer skade enn nytte (Primum non nocere: an evolutionary analysis of whether antidepressants do more harm than good). Front. Psychology 3:117 (Published online: 24 April 2012).).)

Kjemisk forbindelse i marihuana kan hjelpe mot hjernekreft

Marijuana Compounds Could Beat Back Brain Cancer (Kjemisk forbindelse i marihuana kan hjelpe mot hjernekreft)
businessweek.com 11.1.2010
Preliminary lab research suggests they could kill tumor cells

MONDAY, Jan. 11 (HealthDay News) -- Preliminary research suggests that a combination of compounds in marijuana could help fight off a particularly deadly form of brain cancer.

But the findings shouldn't send patients rushing to buy pot: the levels used in the research appear to be too high to obtain through smoking. And there's no sign yet that the approach works in laboratory animals, let alone people. (...)

In the new study, researchers tested THC and cannabidiol, another compound from marijuana, on brain cancer cells. The findings appear in the January issue of Molecular Cancer Therapeutics. (...)

Marijuana Chemical Improves Senses in Cancer Patients
medpagetoday.com 22.2.2011
A synthetic form of THC -- the main active chemical in marijuana -- may help patients with advanced cancer overcome problems with their senses of taste and smell and regain their enjoyment in eating, a pilot study showed. (...)

- Hukommelsesendringene er en stor nedtur for bruken av medisinsk marihuana, ifølge forskerne

Mouse Study Shows How Pot Clouds Memory (Studie på mus viser hvordan marihuana negativt påvirker hukommelse)
philly.com 1.3.2012
THURSDAY, March 1 (HealthDay News) -- Scientists studying mice say they better understand how marijuana impairs working memory, the ability to momentarily retain and utilize information needed for comprehension and learning.

The study, published in the March 2 print issue of Cell, found that THC, the chief psychoactive ingredient in marijuana, impairs memory by affecting passive support cells known as astroglia, not active neurons as previously thought.

Hukommelsesendringene er en stor nedtur for bruken av medisinsk marihuana, ifølge forskerne (The memory changes are a major downside to the use of medical marijuana, the researchers said.) (...)

The study authors said these cells, also known as astrocytes, could have additional effects on other forms of memory. They said their findings shed light on how the brain works and could eventually help scientists find a way to deal with working memory problems stemming from other causes.

Research involving animals should be considered preliminary because the results often don't have implications for humans. (...)

(Anm: Acute Cannabinoids Impair Working Memory through Astroglial CB1 Receptor Modulation of Hippocampal LTD. Cell 2012;148(5):1039-1050 (2 March).)

Don’t forget it! Marijuana Impairs Memory (Ikke glem det! Marihuana svekker hukommelsen)
ivanhoe.com 7.3.2012
(Ivanhoe Newswire) – Medical marijuana is often prescribed to relieve symptoms associated with numerous diseases, including arthritis, dystonia, insomnia, seizures, and Tourette's syndrome, but it comes with a cost, your memory.

Marijuana's major psychoactive ingredient (THC) impairs memory independently of its direct effects on neurons, the ability to transmit information. The side effects stem instead from the drug's action on astroglia, passive support cells long believed to play second fiddle to active neurons.

"Astroglial cells (also known as astrocytes) have been viewed as cells that support, protect and feed neurons for the last 100 to 150 years," Giovanni Marsicano of INSERM in France was quoted saying. "Over the last decade, evidence has accumulated that these cells play a more active role in forging the connections from one neuron to another."

With their experiment on mice, Marsicano and his colleagues didn’t set out to discover how marijuana causes its cognitive side effects. Rather, they wanted to learn why receptors that respond to both THC and signals naturally produced in the brain are found on astroglial cells. These cannabinoid type-1 (CB1R) receptors are very abundant in the brain, primarily on neurons of various types.

"This is the first direct evidence that astrocytes modulate working memory," Xia Zhang of the University of Ottawa in Canada, was quoted saying. (...)

(Anm: Acute Cannabinoids Impair Working Memory through Astroglial CB1 Receptor Modulation of Hippocampal LTD. Cell 2012;148(5):1039-1050 (2 March).)

Marihuana kan hemme immunforsvaret, forårsake kreft, DNA-skader, depresjoner, psykoser, hjerneskader etc.

Cannabis use tied to psychosis recovery trouble (Bruk av marihuana knyttet til problemer med psykose-rekonvalens)
reuters.com 1.3.2012
Related NewsPot tied to more trouble with psychosis recovery

(Reuters) - People who suffer an episode of psychotic symptoms may want to steer clear of marijuana afterwards, according to a study from the Netherlands.

Researchers, whose findings appeared in the Journal of Clinical Psychiatry, found that people who kept smoking cannabis after a psychotic break tended to have certain problems in recovery.

The effects were fairly small and seemed to be limited to social life and financial independence, rather than mental health symptoms. But the findings did support conventional wisdom that people who have ever suffered from psychosis should avoid smoking marijuana. (...)

Cannabis hemmer immunforsvaret
aftenposten.no 1.4.2011
Den kjemiske forbindelsen tetrahydrocannabinol, THC, i cannabis påvirker immunforsvaret. Det er også denne forbindelsen som gjør en «høy» når man røyker hasj eller marihuana. Forsøk med mus viser at THC forårsaker en massemobilisering av celler som demper immunforsvaret, har forskere ved universitetet i south Carolina funnet ut. Cellene kalles MDsCs (myeloidderived suppressor cells), og deres effekt på immunforsvaret gjør kroppen åpen for infeksjoner av alle slag, samt visse former for kreft. (...)

Marijuana Linked with Earlier Onset of Schizophrenia in Research Review
healthland.time.com 8.2.2011
Many studies have linked marijuana use with early onset of psychosis. The question is, does smoking marijuana cause earlier psychosis? A new review of 83 studies involving more than 22,000 participants seeks an answer. (...)

In the paper, published in the Archives of General Psychiatry, they conclude that their results "provide evidence for a relationship between cannabis use and earlier onset of psychotic illness and they support the hypothesis that cannabis use plays a causal role in the development of psychosis in some patients." (...)

Cannabis Use Linked to Earlier Psychosis
medpagetoday.com 7 .2.2011
Psychotic illness occurs significantly earlier among marijuana users, results of a meta-analysis suggest. (...)

Cannabis hämmar immunförsvaret
svt.se 29.11.2010
Cannabis kan ge ökad risk för cancer och infektioner.

Marijuanarökning kan utlösa en dämpning av kroppens immunförsvar. Nu har forskarna funnit varför brukare av cannabis är mer mottagliga för vissa typer av cancer och infektioner.

Cannabis är en av de mest använda missbruksdrogerna i världen. Man har länge misstänkt att en av effekterna är en försvagning av immunförsvaret. Nu tror forskarna att orsaken till dämpningen är en nyligen upptäckt typ av immunceller, kallade MDSC. (...)

(Anm: cannabis, eller cannabispreparater, fellesnavn for de narkotiske stoffene som utvinnes av en underart av hamp (...) Det er toppskuddene og hunnblomsterstanden som gir de forskjellige produktene: marihuana, hasjisj, hasjolje og andre cannabispreparater. Kilde: Store norske leksikon.)

Marijuana and Depression Possibly Linked (Marihuana og depresjon mulig linket)
depression.about.com 9.7.2010
According to a new study, children and teens who smoke marijuana may be at greater risk of developing depression later on. The study does not make clear, however, whether marijuana itself is to blame.

For the study, researchers used data from more than 50,000 adults in 17 countries taking part in a World Health Organization mental health study.

Overall, a modest association was found between smoking marijuana before age 17 and later depression, with there being a 50% increase in the risk of experiencing an episode of depression after the age of 17. (...)

Early pot smoking, depression may be linked (Tidlig marihuana røyking kan være linket til depresjon)
reuters.com 6.7.2010
(Reuters Health) - Children and teenagers who smoke marijuana may have a somewhat heightened risk of developing depression, a new study suggests -- though whether the drug itself is to blame is not clear. (...)

Teen Marijuana Use Might Have Lasting Effects on Mood, Anxiety (Ungdommer som bruker marihuana kan få langvarige påvirkninger av sinnsstemning, angst)
health.com 23.12.2009
WEDNESDAY, Dec. 23 (HealthDay News) — Marijuana use among teens may trigger neurological changes in the developing brain that lead to increased anxiety and stress levels that could persist into adulthood, new animal research suggests.

Selv om resultatene kun stammer fra arbeid utført på unge og voksne laboratorierotter — ennå ikke gjentatt på mennesker— tyder arbeidet på visse problematiske endringer av nivåene av nøkkelkjemikaler i hjernen, dvs. serotonin og norepineprin, som kan vedvare lenge etter at bruken av marihuana opphører. "Her var målet bare å , forstå de underliggende nevrologiske mekanismer bak de spesifikke fenomen på depresjon og angst observert i tidligere studier blant ungdommer klinisk eksponert for cannabis,” forklarte studieforfatter dr. Gabriella Gobbi, en forsker innen psykiatri på Research Institute ved McGill University Health Centre i Montreal. (...) (Although the finding stems solely from work conducted with adolescent and adult lab rats — not yet replicated among humans — the work suggests that certain troublesome changes in levels of the key brain chemicals serotonin and norepinephrine may linger long after marijuana use ceases. “Here, the goal was simply to understand the neurological mechanism that could be underlying the specific phenomenon of depression and anxiety observed in previous studies among adolescents chronically exposed to cannabis,” explained study author Dr. Gabriella Gobbi, a psychiatric researcher at the Research Institute of the McGill University Health Centre in Montreal.)

Marijuana Damages DNA and May Cause Cancer (Marihuana skader DNA og kan forårsake kreft)
livescience.com 13.6.2009
A lot of studies have shown marijuana is not good for you. It can fry the brain and contribute to psychosis. The latest one finds "convincing evidence" that marijuana smoke damages the genetic material DNA in ways that could increase the risk of cancer.

Toxic substances in tobacco smoke can damage DNA and increase the risk of lung and other cancers. However, there has been uncertainty over whether marijuana smoke has the same effect.

Scientists are especially concerned about the toxicity of acetaldehyde, present in both tobacco and marijuana. However, it has been difficult to measure DNA damage from acetaldehyde with conventional tests. (...)

Using a highly sensitive new method called modified mass spectrometry, Rajinder Singh at the University of Leicester and colleagues found the data they sought, they report in the June 15 issue of Chemical Research in Toxicology, a journal of the American Chemical Society. (...)

Earlier this year, a separate study found evidence that adolescents and young adults who smoked a lot of marijuana are more likely than non-users to have disrupted brain development. Research in 2007 found pot smokers have on average a 41 percent increased risk of developing psychotic disorders later in life.

The study was funded by the European Union Network of Excellence, the Medical Research Council and other groups. (...)

(Anm: Evaluation of the DNA Damaging Potential of Cannabis Cigarette Smoke by the Determination of Acetaldehyde Derived N2-Ethyl-2′-deoxyguanosine Adducts. Chem. Res. Toxicol., 2009, 22 (6), pp 1181–1188 (June 15).)

Marihuana øker risiko for psykoser
dagbladet.no 30.7.2007
(...) All forskning om emnet gjort til nå er gjennomgått systematisk. Resultatene publiseres i det medisinske tidsskriftet The Lancet.

- Forskningsresultatene viser at marihuana ikke er så harmløst som mange tror, sier Stanley Zammit, forsker ved avdeling for psykologisk medisin ved Universitetet i Cardiff.

- Unge mennesker bør advares om at cannabisbruk kan få veldig alvorlige konsekvenser siden i livet, erklærer han i en pressemelding fra universitetet. (...)

Marijuana linked to brain damage (Marijuana linket til hjerneskade)
Los Angeles Times 5.12.2005
Ugdommer som jevnlig røyker marihuana risikerer skade på en essensiell nervebane i hjernen assosiert med språkutvikling, og enkelte predisponert for schizofreni kan pådra seg sykdommen i ung alder, sa forskerne onsdag, og på møtet til Radiological Society of North America. (Adolescents who regularly smoke marijuana risk damaging a key brain pathway associated with language development, and some predisposed to schizophrenia may contract the illness early, researchers said Wednesday, also at the meeting of the Radiological Society of North America.)

Hjerneskanninger avslørte mikroskopiske uregelmessigheter i et område av hjernen som styrer høyere aspekter av språk og lyttefunksjoner hos ungdommer som er tunge marihuanarøykere. (Brain scans revealed microscopic abnormalities in a region of the brain that governs higher aspects of language and listening functions in adolescents who are heavy marijuana smokers.)

Liknende skade på buntene av fibrer, kalt arcuate fasciculus, som forbinder område for Broca i den venstre pannelapp og Wernicke i den venstre temporallappen ble funnet i hjernene til studerte marihuanarøykere og schizofrenikere. (...) (Similar damage to the bundle of fibers, called the arcuate fasciculus, that connect Broca's area in the left frontal lobe and Wernicke's area in the left temporal lobe was found in the brains of marijuana smokers and schizophrenics studied.)

- Risiko for trafikkulykker dobles når fører er under påvirkning av marihuana

Risk Of Road Traffic Accidents Doubles When Driving Under The Influence Of Marijuana (Risiko for trafikkulykker dobles når fører er under påvirkning av marihuana)
medicalnewstoday.com 10.10.2011
(...) According to the investigators 8 of 9 studies found that drivers who use marijuana are significantly more likely to be involved in crashes than drivers who do not. Only one small case-control study conducted in Thailand, where the prevalence of marijuana use is far lower than reported elsewhere, was the exception.

Full study findings are published online in Epidemiologic Reviews. (...)

Marijuana linket til aggressiv testikkelkreft

Dobbel kreftrisk ved cannabisrøyking
aftenposten.no 13.2.2009
Unge menn som røyker hasj og marihuana dobler risikoen for testikkelkreft.

I en amerikansk studie har forskere funnet ut at risikoen for å få testikkelkreft øker kraftig for menn som bruker cannabis tidligere i livet.

Og ikke bare det: Det er også snakk om en særlig aggressiv form for testikkelkreft, rapporterer The Guardian på nett. (...)

Marijuana Linked to Aggressive Testicular Cancer (Marijuana linket til aggressiv testikkelkreft)
healthfinder.gov 9.2.2009
But not all are sure that adolescents' use of cannabis causes cells to proliferate. (...)

Langtidsbruk av marihuana svekker lungefunksjon

Long-Term Marijuana Use May Impair Lung Function (Langtidsbruk av marihuana svekker lungefunksjon)
healthfinder.gov 21.2.2007
Data shows wheezing and phlegm similar to that of cigarette smokers

-- People who smoke marijuana for a long time face many of the same kinds of respiratory problems -- such as phlegm, coughing and wheezing -- as long-term cigarette smokers, say researchers at the Yale School of Medicine.

They reviewed previous studies from 1966 to 2005 that examined the association between marijuana and pulmonary function and respiratory complications. Some of the studies found a link between short-term marijuana use and relaxation and opening of the air passages.

However, other studies identified an association between long-term marijuana use and increased risk of respiratory symptoms, suggestive of obstructive lung disease. The data did not show an association between long-term marijuana smoking and airflow obstruction (emphysema), the Yale researchers said.
Their study is published in the current issue of the journal Archives of Internal Medicine. (...)

(Anm: Effects of Marijuana Smoking on Pulmonary Function and Respiratory Complications. Arch Intern Med. 2007;167:221-228.)

Marihuana tredobler risiko for alvorlige munnsykdommer

Marijuana Bad for the Gums
healthfinder.gov 6.2.2008
Regular use ups risk of periodontal disease, study finds.

TUESDAY, Feb. 5 (HealthDay News) -- Pot smokers face many of the same health consequences that tobacco users do, such as an increased risk of heart disease, but until now, it wasn't known that marijuana use could also destroy gum tissue.

In the Feb. 6 issue of the Journal of the American Medical Association, researchers reported that heavy marijuana users have as much as three times the risk of developing serious gum disease compared to those who haven't smoked pot. (...)

Marihuana kan øke risiko for hjerteanfall og slag, ifølge studie

Marijuana may up heart attack, stroke risk: study (Marihuana kan øke risiko for hjerteanfall og slag, ifølge studie)
reuters.com 13.5.2008
WASHINGTON (Reuters) - Heavy marijuana use can boost blood levels of a particular protein, perhaps raising a person's risk of a heart attack or stroke, U.S. government researchers said on Tuesday.

Dr. Jean Lud Cadet of the National Institute on Drug Abuse, part of the National Institutes of Health, said the findings point to another example of long-term harm from marijuana. But marijuana activists expressed doubt about the findings. (...)

Tidsskriftsartikler linker marijuana til schizofreni

Journal articles link marijuana to schizophrenia (Tidsskriftsartikler linker marijuana til schizofreni)
canada.com 28.8.2006
A pair of articles in the Canadian Journal of Psychiatry has resurrected the "reefer madness" argument about marijuana and its links to mental illness.
Cannabis use can trigger schizophrenia in people already vulnerable to the mental illness -- and this fact should shape marijuana policy, argue two psychiatric epidemiologists in this month's journal. (...)

"...hjerneskade trigger fødsel av nye celler"

Human brain can make new cells, study finds (Studie viser at menneskelig hjerne kan produsere nye celler)
By Maggie Fox, Health and Science Editor
reuters.com 16.2.2007
WASHINGTON (Reuters) - New evidence shows that the human brain can manufacture fresh brain cells, researchers said on Thursday in a study that may lead to better ways to treat brain damage and disease.

Scientists had known that other animals, such as rats and mice, make new brain cells throughout their lives and there had been indirect evidence that humans being can, too.

Using magnetic resonance imaging, or MRI, scans and electron microscope images of tissue donated from the brains of people who died, Maurice Curtis of the University of Auckland in New Zealand and Peter Eriksson of Sahlgrenska Academy in Goteborg, Sweden, and colleagues found the elusive cells.

Just as in mice and rats, these cells are born in one part of the brain and then migrate to the olfactory bulb, where smells are processed. They mature into neurons on the way.

In animals, they said, brain damage prompts the birth of new cells. "Our study provides the foundation for this possibility in the adult human brain," they wrote in their report, published in the journal Science.

Humans have far more developed brains, so searching for these cells has been harder than it was in rodents.

In mice and rats it has been clear these cells are born in the forebrain and then migrate to the smell center. There, they can help the animals learn and adapt to new smells.

Smell is less important for humans, but it is still important for sensing dangers from smoke, for instance, or rotten food.

And studies show that the loss of smell may be an early sign of brain-destroying illnesses such as Parkinson's, the researchers said -- a hint that these cells may be important.

"This study is exciting because it reveals a group of brain cells in the adult human brain that are continuously regenerating," said Dr. Mark Baxter of Britain's Oxford University.

"Animal studies have pointed to the existence of such groups of cells, but it has been difficult to determine whether they exist in the human brain as well," Baxter, who was not involved in the research, said in a statement.

"This opens another direction by which we may discover ways to repair human brains that are damaged from injury or diseases, and underscores the importance of animal research in guiding biomedical research in humans," Baxter said.

Another expert, Sebastian Brandner, head of the Division of Neuropathology at the Institute of Neurology at University College London, agreed.

"These findings are important for several reasons: Understanding stem cell biology is essential to study brain repair in neurodegenerative diseases such as Alzheimer's and it is even possible that stem cells are the source of some brain tumors," Brandner said in a statement. (...)

- Hjernen reparerte seg etter skade

- Hjernen reparerte seg
aftenposten.no 4.7.2006
Terry Wallis våknet etter 19 år i koma fordi hjernen reparerte seg selv, sier en ny amerikansk studie.

Fremgangen har blitt nært fulgt av en gruppe forskere fra USA og New Zealand. De tror at en langsom prosess av hjernereparering og gjentilkopling av nerver førte til Wallis’ oppvåkning, melder avisen The New York Times.

I en artikkel i tidsskriftet The Journal of Clinical Investigation skriver forskerne at Wallis’ hjerne kan ha reparert seg selv, og de håper at resultatene av forskingen kan føre til at man i fremtiden kan avgjøre hvilke komapasienter som har best sjanser for å våkne opp. (...)

Men Henning Voss, leder av studien og professor i fysikk og radiologi ved Cornell University i New York sier til BBC at Wallis’ situasjon er unik, og at det ikke er tilfellet at hjernereparasjonen skjer med alle pasienter. (...)

Docs: Comatose Man's Brain Rewired Itself
washingtonpost.com 4.7.2006
-- Doctors have their first proof that a man who was barely conscious for nearly 20 years regained speech and movement because his brain spontaneously rewired itself by growing tiny new nerve connections to replace the ones sheared apart in a car crash. (...)

Tung marijuanabruk linket til hukommelse- og lærevansker

Heavy Marijuana Use Linked to Memory and Learning Deficits (Tung marijuanabruk linket til hukommelse- og lærevansker)
medpagetoday.com 13.3.2006
- Heavy marijuana use for five years or more may impair memory and slow cognitive function, according to researchers here.

Compared with controls, persons who used marijuana at least four days a week had lower scores on a standardized test of verbal learning skills and were generally "slow learners," Lambros Messinis, Ph.D., and colleagues of University Hospital Patras reported in the March 14 issue of Neurology.

Moreover, while the impairment was greater among long term users -- those who regularly used marijuana for at least 10 years -- it was also evident among those who used for only five years, they wrote.

The study assessed neuropsychological status in three groups: 20 current, long-term frequent cannabis users; 20 current, short-term cannabis users, and 24 controls who had used cannabis at least once but no more than 20 times in their lives and who had not used the drug in the previous two years.

Bruk av marihuana tidlig i svangerskap øker barns risiko for kreft

Marijuana use in early pregnancy increases child’s risk of cancer (Bruk av marihuana tidlig i svangerskap øker barns risiko for kreft)
BMJ 2006;332:1292 (3 June)
Mothers who use marijuana in the first trimester may increase the risk of their child developing neuroblastoma, the second most common solid tumour found in children, a US study has found.

The results of the case control study to investigate the role of illicit drugs in the development of the tumour show that mothers’ use of any illicit or recreational drug during pregnancy was associated with an increased risk of neuroblastoma in the offspring (odds ratio 1.82 (95% confidence interval 1.1 to 3.0) (Cancer Causes and Control 2006;7:663-9). (...)

(Anm: neuroblastom; ganglioneuroblastoma, vondarta, adrenalindannande svulst av nevroblastar hos barn under 10 års alder, gjerne frå det autonome nervesystemet (sympatikonevroblastom) eller binyremargen; gir auka utskiljing av katekolaminar i urinen; svulstvev med reseptorar for NGF, koda av TRK-genet, er minst vondarta men ein forlenging av ein arm på kromsom 17 vil varsla dårleg prognose; svulsten sit gjerne i bakre del av mediastinum
EN neuroblastoma Kilde: Norsk medisinsk ordbok.)

Substansmisbruk linket til hjerneslag

Drug use Linked to Stroke (Substansmisbruk linket til hjerneslag)
ivanhoe.com 22.2.2006
-- A new study reveals one-fifth of young adults whose blood vessels ruptured inside their brain often abused drugs. Researchers say, among them, more than 40 percent had blood vessel malformations.

For the study, researchers analyzed 307 patients with intracerebral hemorrhage (ICH), a stroke caused by a blood vessel bursting inside the brain. Seventy-five patients were age 49 or younger. Twenty percent of them had drugs in their system.

"The dominant drug of abuse was cocaine, long recognized as a risk factor for ICH," says Michael Hoffmann, M.D., lead author of the study and director of the stroke program at the University of South Florida-Tampa General Hospital. "Marijuana was another frequently abused drug and is beginning to emerge as a risk factor for stroke." He notes amphetamines were also commonly abused.

The study revealed surprisingly high mortality rates for the younger ICH sufferers. Most of the patients studied were able to live independently three to six months after their ICH with only mild to moderate cognitive impairment that tends to improve over time.

According to Dr. Hoffmann, the degree and nature of disability at six months is the focus of the extension of this study. He says: "Intensive neurocritical care is the key to successful outcome. Good medical care can salvage a high quality of life after a stroke."

SOURCE: American Stroke Association's International Stroke Conference in Kissimmee, Fla., Feb. 16-18, 2006 (...)

When Teenagers Abuse Prescription Drugs, the Fault May Be the Doctor's

When Teenagers Abuse Prescription Drugs, the Fault May Be the Doctor's (When Teenagers Abuse Prescription Drugs, the Fault May Be the Doctor's)
nytimes.com 27.12.2005
(...) This is hardly unique to my clinic. Several studies report that since 1992, the number of 12- to 17 -year-olds abusing controlled prescription drugs has tripled.

In fact, dabbling with some of the pharmaceutical industry's finest psychoactive compounds constitutes the fastest growing type of drug abuse in the United States, outpacing marijuana abuse by a factor of two. One of my patients, Mary, illustrates this trend all too well. A voracious reader and a talented musician in her high school orchestra, Mary at 16 is also a "garbage head," meaning that she will ingest anything she thinks will give her a high. (...)

Ny mekanisme for neurodegenerative effekter av amfetaminer

New Mechanism For Neurodegenerative Effects Of Amphetamines In Mice Found, University Of Toronto (Ny mekanisme for neurodegenerative effekter av amfetaminer funnet i mus, Universitetet i Toronto)
medicalnewstoday.com 6.4.2006
University of Toronto researchers have discovered a new mechanism for the neurodegenerative effects of amphetamines. These drugs are converted in the brain into free radicals, highly reactive molecules that cause neurodegenerative brain damage and whose effects manifest and linger long after the amphetamine has left the body.

"The question of whether amphetamines like ecstasy (MDMA) or methamphetamine (METH) cause neurodegeneration in humans is one of the most controversial areas in science today," says Professor Peter Wells of the Leslie Dan Faculty of Pharmacy, lead author of the study that appears in the April issue of the journal of the Federation of American Societies for Experimental Biology (FASEB Journal). "The short-term effects of these drugs - hypothermia, electrolyte imbalances and an elevated risk of heart attack - are well understood, but not their long-term consequences."

Wells and doctoral students Winnie Jeng, Annmarie Ramkissoon and Toufan Parman theorized that prostaglandin H synthase (PHS) - an enzyme that synthesizes a range of hormones throughout mammalian life - is the catalyst that transforms amphetamines into free radical products that react with oxygen in the body to enhance the formation of highly toxic reactive oxygen species. These toxic forms of oxygen are implicated in neurodegenerative diseases such as Alzheimer's and Parkinson's because of the increased oxidative stress they place on the body, resulting in irreversible damage to DNA, proteins and lipid membranes. Organs such as the brain, which lack abundant antioxidant protection, are particularly vulnerable to oxidative stress.

To approximate an acute human exposure, the researchers administered four doses of either MDA (the major metabolite of ecstasy) or METH at two-hour intervals to young adult mice. In the case of MDA, before the first drug injection an additional group of mice was given a single dose of aspirin (acetylsalicylic acid), which is known to inhibit PHS and block its ability to convert drugs to free radical products.

Over a six-month period, following the single day's treatment of MDA or METH, the mice were observed and had their motor co-ordination tested by walking on a rotating rod. Normally, mice balance easily on the rods for extended periods. Within two weeks of the last treatment, all the mice given MDA or METH without aspirin had trouble with this task and remained disabled for at least six months. These mice also exhibited enhanced molecular damage to the DNA in their brains and a loss of nerve terminals that remained for at least one week after exposure to MDA or METH. The mice pretreated with aspirin had less molecular damage to their DNA and fewer motor disabilities, suggesting that the neurodegenerative effects of MDA are dependent upon its conversion by PHS into a reactive free radical product.

"Our findings reveal how exquisitely susceptible brains are to this kind of damage, at least in mice," Wells says. "The long-term negative effects in the mice treated with MDA or METH all resulted from a single day's dosage that approximated the higher range of human exposures."

Although the team's findings cannot be extrapolated to humans without further study, Wells believes they do suggest a novel mechanism through which amphetamines may contribute to neurodegeneration.

"Our hypothesis about PHS-catalyzed conversation may also be relevant to the neurodegenerative risks associated with aging," he says. "Preliminary results from other studies suggest that PHS may convert other compounds in our brains into free radicals, and there is some evidence in the clinical literature that suggests patients who take high doses of PHS-inhibiting drugs such as aspirin may experience less neurodegeneration. The potential of substances like aspirin to prevent neurodegenerative damage merits more examination, particularly among people who take it chronically for pain."

This study was funded by the Canadian Institutes of Health Research, with support from the National Institute on Drug Abuse (U.S.A) and Health Canada's Healthy Environments and Consumer Safety Branch. (...)

Ingen nybildning av celler i hjärnbarken

Ingen nybildning av celler i hjärnbarken
netdoktor.passagen.se 14.8.2006
Hjärnceller i delar av cortex, även kallad hjärnbarken, nybildas inte. Det visar ett antal forskare från bland annat Karolinska Institutet. Den uppmärksammade stamcellsforskaren Jonas Frisen hör till forskarna som har lyckats mäta åldern på celler i hjärnan på människor med den så kallade kol-14 metoden. Att det sker nybildning av celler i andra delar av hjärnan än just hjärnbarken är känt sedan tidigare. Rönen presenteras i den vetenskapliga tidskriften PNAS. (...)

Diverse artikler

Experts Tell the Truth about Pot
scientificamerican.com 22.2.2012
Marijuana use can be problematic but only rarely leads to addiction

In the classic 1936 cult film Reefer Madness, well-adjusted high school students who try marijuana suddenly sink into a life of addiction, promiscuity, aggression, academic failure, homicide and mental illness. The movie concludes with the ominous warning that “The dread marijuana may be reaching forth next for your son or daughter ... or yours ... or YOURS!” Newspaper headlines of the day often reflected a similar sentiment. On February 10, 1938, a headline in the Beloit (Wisc.) Daily News read, “Authorities Warn against Spread of Marijuana Habit—Insanity, Degeneracy and Violence Follow Use of Weed.” (...)

– Ein stor siger for MS-pasientar
nrk.no 14.2.2012
Cannabis-medisinen Sativex kjem som munnspray. Det er låge konsentrasjonar av cannabis i medisinen, og ein vil oppnå liten ruseffekt.

For første gong vil eit cannabis-basert lækjemiddel bli legalisert i Noreg. Sosiolog Willy Pedersen trur det vil auke livskvaliteten til svært mange pasientar. (...)

Overraska
Professor i sosiologi og forfattar av boka «Cannabiskulturen», Willy Pedersen, vart overraska av at norske helsestyresmakter no vil legalisere eit cannabis-basert lækjemiddel.

– Eg vart overraska. Eg har oppfatta norske styresmakter som å vere veldig nølande på dette feltet. Det har lenge blitt vist stor skepsis til dette i Noreg.

Pedersen har tidlegare intervjua mange MS-pasientar om bruken av cannabis. Han kjenner til at fleire har måtte oppsøkt kriminelle miljø for å få tak i stoffet, som kan ha ein spasmedempande og smertelindrande effekt.

– Dette er ein klar siger for mange MS-pasientar. Det vil føre til ein stor levekårsforbetring for denne gruppa. Eg kjenner til at mange pasientar har vore svært fortvila fordi det har vore ulovleg. No vil dei sleppe å kome i risiko for politietterforsking. (...)

Drug Monitoring
Investigating beneficial drug reactions
BMJ 2012;344 (4 January)
(...) All clinicians are familiar with drugs that have multiple uses. Codeine, for example, may be given to reduce cough (when it may have the adverse effect of constipation) or to treat diarrhoea (when suppressing the cough reflex becomes the unintended adverse effect). (...)

Other examples abound, in the professional and lay literature, such as recent discussion, including on the BBC, concerning clomipramine’s potential to have a beneficial effect on brain tumours. (...)

In general such potential repurposings have been identified serendipitously by alert doctors who have observed an unexpected beneficial effect that might be due to a prescribed drug, in the same way that they might note possible adverse drug reactions. However, adverse reactions are identified in numerous ways that should also be adopted and modified appropriately for beneficial drug reactions. Of course, as with adverse reactions, such possibilities need careful investigation, again using the validated methods already in place. (...)

Politiet frykter at flere unge vil begynne med narkotika
nrk.no 28.11.2011
Aleksander Østvold ved Rud videregående i Bærum har ikke prøvd narkotika selv, men sier mange av vennene har gjort det. Andre elever forteller at de som selger ikke bryr seg om at noen av de som kjøper er svært unge.

Ungdom helt ned i 12-årsalderen har blitt tatt for bruk av marihuana. Nå frykter politiet en ny narkotrend blant elever på ungdomsskolen. (...)

15-åringer selger stoff
Nå frykter politiet at dette er en ny trend blant ressurssterke ungdom. Nylig ble tre 14-åringer tatt for kjøp i Oslo sentrum.

– Vi har også avdekket flere 15-åringer som distribuerer marihuana til andre ungdommer på ungdomsskoletrinnet.

På en skole i Asker og Bærum politidistrikt forteller flere av elevene at de kjenner noen som bruker stoffet.

– Det veldig mange som sier at alkohol dreper cellene, mens hasj bare lammer dem, så derfor mener de at alkohol er farligere, sier en av jentene på skolen. (...)

Hvorfor snakker ingen om legalisering?
nrk.no 18.11.2011
Cannabis-bruk er relativt normalt i Norge. Mange har forsøkt det, en mindre del bruker det jevnlig.

– Det er det rundt cannabisen som er problemet - kulturen og kriminaliteten, sier professor Willy Pedersen. (...)

De fleste regner cannabisbruk som lite risikabelt. Ifølge Pedersen er en del foreldre klar over ungdommens eksperimentering med stoffet, uten at det bekymrer så veldig mye mer enn om de flørter med alkohol og tobakk.

Det er ikke uvanlig å mene at cannabisbruk ikke er veldig skadelig. Ikke mer skadelig enn alkohol og tobakk, i alle fall.

– Ja, og det er forholdsvis godt dokumentert at det stemmer, fortsetter Pedersen.

– Men, det skal jo også sies at alkohol og tobakk er svært skadelige stoffer. (...)

Big Alcohol Fueling Opposition to California Marijuana Initiative
huffingtonpost.com 16.9.2011
According to a recently filed campaign finance report, the campaign to defeat a marijuana legalization initiative in California is receiving substantial funding from the alcohol industry. Now marijuana advocates are fighting back, calling on the opposition campaign to explain why it is working with Big Alcohol to keep marijuana illegal.

On September 7th, the California Beer and Beverage Distributors contributed $10,000 to the No on Prop. 19 campaign, which calls itself "Public Safety First." Proposition 19 would establish a legally regulated marijuana market in which marijuana is controlled and taxed in a fashion similar to alcohol.

It's clear why the alcohol industry is in this fight -- to protect its turf and keep Californians drinking. This is the same California Beer and Beverage Distributors gave $100,000 to oppose Proposition 5, the Nonviolent Offender Rehabilitation Act (NORA), which would have reduced marijuana possession from a misdemeanor to an infraction. With marijuana being the second most popular recreational substance (despite its prohibition), the booze industry must recognize the threat legal marijuana poses to its bottom line. Thus, it has a vast financial interest in keeping marijuana illegal and steering Californians away from using it. (...)

But why does the No on Prop. 19 campaign share Big Alcohol's goal of an alcohol-only society? It seems odd that a group that purports to be committed to enhancing public safety wants to ensure Californians can only drink and cannot use marijuana as a safer recreational alternative. (...)

Impact of cannabis use on thalamic volume in people at familial high risk of schizophrenia
Br J Psychiatry. 2011 Sep 8. [Epub ahead of print]
BACKGROUND: No longitudinal study has yet examined the association between substance use and brain volume changes in a population at high risk of schizophrenia.

AIMS: To examine the effects of cannabis on longitudinal thalamus and amygdala-hippocampal complex volumes within a population at high risk of schizophrenia.

METHOD: Magnetic resonance imaging scans were obtained from individuals at high genetic risk of schizophrenia at the point of entry to the Edinburgh High-Risk Study (EHRS) and approximately 2 years later. Differential thalamic and amygdala-hippocampal complex volume change in high-risk individuals exposed (n = 25) and not exposed (n = 32) to cannabis in the intervening period was investigated using repeated-measures analysis of variance.

RESULTS: Cannabis exposure was associated with bilateral thalamic volume loss. This effect was significant on the left (F = 4.47, P = 0.04) and highly significant on the right (F = 7.66, P = 0.008). These results remained significant when individuals using other illicit drugs were removed from the analysis.

CONCLUSIONS: These are the first longitudinal data to demonstrate an association between thalamic volume loss and exposure to cannabis in currently unaffected people at familial high risk of developing schizophrenia. This observation may be important in understanding the link between cannabis exposure and the subsequent development of schizophrenia. (...)

Smoking Cannabis Increases The Risk Of Depression In The Case Of Genetic Vulnerability
medicalnewstoday.com 11.10.2011
Young people who are genetically vulnerable to depression should be extra careful about using cannabis: smoking cannabis leads to an increased risk of developing depressive symptoms. This has emerged from research carried out by Roy Otten at the Behavioural Science Institute of Radboud University Nijmegen that is published in the online version of the scientific journal Addiction Biology. Two-thirds of the population have the gene variant that makes one sensitive to depression. (...)

(Anm: cannabis, eller cannabispreparater, fellesnavn for de narkotiske stoffene som utvinnes av en underart av hamp (...) Det er toppskuddene og hunnblomsterstanden som gir de forskjellige produktene: marihuana, hasjisj, hasjolje og andre cannabispreparater. Kilde: Store norske leksikon.)

Don't Rule Out Marijuana as Trigger for Schizophrenia
clinicalpsychiatrynews.com 21.9.2011
CHICAGO – The idea that cannabis use might trigger a patient’s first psychotic episode is one that needs to be taken seriously, Dr. John Csernansky said at a seminar on "Reinventing Inpatient Psychiatry."

"Are there patients out there who have schizophrenia who would not have had it without substance abuse? There may be," said Dr. Csernansky, chairman of the department of psychiatry and behavioral sciences at Northwestern University, Chicago. "This is a very hot topic and one that is genuinely frightening."

Cannabis use is frequent within 1-2 years before the first psychotic break. A variety of epidemiological studies suggest that cannabis use in adolescence (15-18) increases the risk for development of schizophrenia, even years later. A meta-analysis published earlier this year (Arch. Gen. Psychiatry 2011;68:555-61) provides evidence of a relationship between cannabis use and earlier onset of psychosis. The meta-analysis, which included data from 83 studies, found that the mean age of psychosis for cannabis users was 2.70 years younger than for nonusers. More than 8,000 patients who reported using psychoactive substances and more than 14,000 who did not were covered by the meta-analysis. (...)

More Evidence That Marijuana-Like Drugs May Help Prevent PTSD
healthland.time.com 23.9.2011 (Time)
Could a marijuana-based medicine potentially prevent the symptoms of post-traumatic stress disorder (PTSD)? If the findings of a new study in rodents hold up, they may offer a new avenue for treatment of an illness that affects at least 7% of Americans during their lifetimes.

For the study, published in the journal Neuropsychopharmacology, researchers exposed rats to severe, Navy Seal-level stress, including restraint, forced swims and anesthetization. Luckier control rats just stayed in their cages and were handled twice by researchers.

Like humans who develop PTSD, the stress-exposed rats later became oversensitized to more moderately stressful stimuli, showing an exaggerated startle response to loud noises, for example. These rats also took longer to recognize that a once scary spot in a cage was now safe. Animals that had experienced traumatic stress also showed related changes in stress hormones. (...)

U.S. Rules That Marijuana Has No Medical Use. What Does Science Say?
healthland.time.com 11.7.2011 (Time)
The U.S. Drug Enforcement Administration (DEA) ruled on Friday that marijuana has "no accepted medical use" and should therefore remain illegal under federal law — regardless of conflicting state legislation allowing medical marijuana and despite hundreds of studies and centuries of medical practice attesting to the drug's benefits.

The judgment came in response to a 2002 petition by supporters of medical marijuana, which called on the government to reclassify cannabis, which is currently a Schedule I drug — like heroin, illegal for all uses — and to place it in Schedule III, IV or V, which would allow for common medical uses.

The DEA ruled that marijuana has "no currently accepted medical use in treatment in the United States," has a "high potential for abuse," and "lacks an acceptable level of safety for use even under medical supervision." (...)

How antidepressants spur brain growth
rsc.org 12.4.2011
Researchers have identified the mechanism by which some antidepressants stimulate the formation of new brain cells, an insight that could lead to improved drugs.

Antidepressants combat depression by increasing levels of serotonin in the brain. But they can also help by stimulating the formation of new brain cells, a process called neurogenesis, which plays an important role in memory. (...)

Early Studies Show Anti-Depressants Boost Brain Cells After Injury
medicalnewstoday.com 19.4.2011
Anti-depressants may help spur the creation and survival of new brain cells after brain injury, according to a study by neurosurgeons at the University of Rochester Medical Center.

Jason Huang, M.D., and colleagues undertook the study after noticing that patients with brain injuries who had been prescribed anti-depressants were doing better in unexpected ways than their counterparts who were not taking such medications. Not only did their depression ease; their memory also seemed improved compared to patients not on the medication.

"We saw these patients improving in multiple ways - their depression was improved, but so were their memory and cognitive functioning. We wanted to look at the issue more, so we went back to the laboratory to investigate it further," said Huang, associate professor of Neurosurgery and chief of Neurosurgery at Highland Hospital, an affiliate of the University of Rochester Medical Center.

The team's findings were published online recently in the Journal of Neurotrauma. (...)

Ökad risk för symtom på psykos bland unga som tog cannabis
dagensmedicin.se 2.3.2011
En ny studie stärker orsakssambandet mellan användning av cannabis och senare utveckling av psykos. (...)

Personer som under de första 3,5 åren börjat använda cannabis hade en nästan fördubblad risk att uppvisa tecken på psykos under en uppföljningsperiod från 3,5 år till 8,4 år efter det att studien startade, jämfört med dem som inte alls använt cannabis.

Personer som uppgav att de hade använt cannabis innan studien startade och sedan fortsatte användningen hade mer än fördubblad risk att ha varaktiga psykotiska symtom under samma uppföljningsperiod som ovan. (...)

(Anm: Cannabis and the increased incidence and persistence of psychosis. BMJ 2011; 342:d719 (1 March).)

Cannabis and the increased incidence and persistence of psychosis
BMJ 2011; 342:d719 (1 March)
(...) Sensible reasoning supports the policy of providing young people with information about the risks of using cannabis.⁹ The case for communication is strengthened by evidence that regular cannabis use in adolescence predicts poorer educational outcomes, increased risk of using other illicit drugs, increased risk of depression, and poorer social relationships in early adulthood.¹⁰

The major challenge, however, is to deter enough young people from using cannabis so that the prevalence of psychosis is reduced. A modelling study suggests that we would need to prevent 2018-4530 young people in the United Kingdom from becoming regular cannabis users to prevent one case of schizophrenia, or to prevent four to five times as many (10 000-23 000) from light cannabis use to achieve the same result.¹¹ (...)

USA: Flere ungdom røyker hasj enn sigaretter
nrk.no 16.12.2010
Marihuanabruken øker raskt blant amerikanske ungdommer.

Én av fem avgangselever ved amerikanske High Schools oppgir at de nylig har røyket marihuana. For første gang siden 1981 foretrekker ungdommen hasj framfor sigaretter.

Etter nesten ti år med tilbakegang, gjør marihuanaen et kraftig «come back» blant amerikanske ungdommer.

I en undersøkelse gjort av amerikanske myndigheter svarer 21,4 prosent av alle High School-avgangselever at de har røyket hasj i løpet av de 30 siste dagene. 19,2 prosent svarer at de har røyket sigaretter i den samme perioden.

Rapporten fra Det amerikanske instituttet for rusmisbruk viser at for første gang siden 1981 har hasj blitt mer populært i denne aldersgruppen, enn sigaretter, skriver Los Angeles Times. (...)

California sa nei til å legalisere marihuana
vg.no 3.11.2010
Californias innbyggere sier nei til å legalisere marihuana, viser prognoser fra folkeavstemningen som ble holdt i forbindelse med mellomvalget i USA.

57 prosent av velgerne ser ut til å ha stemt nei til legalisering av marihuana, mens 43 prosent stemte for, viser en prognose gjengitt av CNN. (...)

– Det vil falle en tåre eller to
nrk.no 3.11.2010
Velgerne i California har stemt mot legalisering av marijuana i nattens valg. Forkjemperne fyrte likevel opp det narkotiske stoffet i natt, og sier de vil fortsette kampen. (...)

Motstanden mot å legalisere det til vanlig bruk er likevel fortsatt stor. Argumentene er mange, blant annet mener de det vil få en negativ innvirkning på arbeidskraften og ved skolebenkene, det vil føre til flere trafikkuhell og arbeidsulykker. (...)

Legalisation doesn’t work (Legalisering virker ikke)
BMJ 2010; 341:c6138 (2 November)
The recent report of the International Centre for Science in Drug Policy (ICSDP) claims that cannabis should be legalised because its use has increased in the past 20 years despite increasing resources being spent on the criminal justice system.¹ The BMJ’s uncritical endorsement of these claims is surprising. (...)

The report has a cavalier attitude towards the harms of cannabis. However, since 2002 several key studies have shown the clear link between cannabis and serious mental health problems, including an increasing risk of developing schizophrenia.³ (...)

Amerikansk milliardær vil legalisere marijuana
tv2nyhetene.no 27.10.2010
George Soros har donert en million dollar til kampanjen for legalisering før avstemningen i California 2. november.

VIL HA LOVLIG MARIJUANA: George Soros har donert en million dollar til kampanjen for legalisering før avstemningen i California 2. november.

Den berømte amerikanske milliardæren George Soros annonserte sin donasjon i Wall Street Journal hvor han hevder at «lovlig marijuana vil bety et stort skritt fremover for samfunnet og at eventuelle problemer vil kunne korrigeres underveis som følge av erfaring».

«Beskatning av et lovlig salg av marijuana vil samtidig spare skattebetalerne milliarder av dollar som i dag går til bekjempelse og fengslinger, mens det ville bety milliarder i statlige inntekter hvert år og mindre korrupsjon», sier Soros i avisen.

Den ungarskfødte milliardæren har tjent en formue som spekulant innen valuta.

California har avstemning 2. november om staten skal tillate privat dyrking, innkjøp og oppbevaring av marijuana til eget bruk. (...)

Marijuana, Prescription Meds Drive Spike in Drug Use (Marihuana, reseptbelagte legemidler driver opp substansforbruket)
Psychiatr News 2010;45(20):6 (October 15) (American Psychiatric Association)
Previous concerns by federal health officials over “doctor shopping” by drug abusers give way to a call by these officials for more patient education on the need to dispose unneeded prescribed medications.

The overall national rate of drug use increased from 2008 to 2009, and the two drug categories that accounted for most of that increase were prescription drugs and marijuana.

The overall rate of illicit drug use in the United States rose from 8 percent of the population over age 11 in 2008 to 8.7 percent one year later, according to the nation's most comprehensive annual substance use survey. Results of the National Survey on Drug Use and Health, conducted by the Substance Abuse and Mental Health Services Administration (SAMHSA), released on September 16, identified nonmedical uses of marijuana and prescription drugs as the key drivers of the increase. (...)

The Munchies, Marijuana and Happiness (Sultfølelsen, marihuana og lykke)
psychologytoday.com 28.7.2010
The munchies may be the key to understanding depression. (Sultfølelsen kan være nøkkelen til å forstå depresjon)

Why does smoking marijuana produce the munchies? What does this peculiar response tell us about our brain? It turns out, quite a lot; particularly with regard to our ability to experience happiness and joy and to avoid obesity and depression. The craving for food while smoking is likely due to the stimulation of marijuana receptors in the feeding centers of our brain. The munchies drew the attention of neuroscientists who then conducted a series of clinical trials using a novel drug, called rimonabant, that potently block the brain's marijuana receptors. Their hope was that blocking the action of the brain's marijuana neurotransmitter system in the feeding center would produce an "anti-munchies" effect, thereby reducing food consumption and providing help to overweight patients. Right from the beginning, the drug worked very well. People reported significantly fewer cravings for food. In addition, many subjects reported that they were also less interested in drinking alcohol, smoking cigarettes or using cocaine. Not surprising, excitement in the medical community grew quickly about the potential benefits that this drug might provide, particularly because obesity is such a major health risk. (...)

What these studies teach us is that our brain's own marijuana neurotransmitter system is necessary for us to feel hungry, to experience happiness and to maintain the brain normal processes, such as neurogenesis, that prevent age-associated depression and cognitive decline. We've learned from our experience with rimonabant that it is dangerous to constantly antagonize this neurotransmitter system. What we do not know is whether it is dangerous to constantly stimulate it. (...)

Pot and perception: Looking at what marijuana really does to you
By John Gilburt, For the Colorado Daily
coloradodaily.com 17.5.2010
Perceptions and thinking: Does the scenery really change?

Obviously it is our brains that change on pot, not the scenery. The way marijuana helps with severe pain, nausea, etc., is by dissociation from the body and from feelings, and altering the reactive thoughts about those feelings.

It's a huge, and welcome, distraction. In some ways, its actions are similar to the anti-depressants that we take, except that the Prozacs creates the dissociation to a much lesser and controlled extent.

Pot seems to work on serotonin, as does Prozac, albeit in different ways. When we smoke pot, some mental functions are enhanced (those that help us survive, for instance) while others take a back seat, primarily to our complex thinking frontal cortex. (...)

Sædcellenes fartshemmelighet avslørt
nrk.no 5.2.2010
Forskere har funnet «bryteren» som gjør sædcellene til supersvømmere. (...)

- Dette kan gjøre at vi kan utvikle et mannlig prevensjonsmiddel eller kanskje finne en måte å forbedre sædcellenes bevegelsesevne for menn som har sædceller som ikke svømmer så bra som de burde, sier han, ifølge nyhetsbyrået AP.

Funnene skal også kunne hjelpe forskerne med å finne ut hvorfor marihuana gjør menn ufruktbare. (...)

- Cannabis kan hemme kreft
aftenposten.no 2.4.2009
(...) Det aktive stoffet i cannabis – THC – ser ut til å kunne hindre kreftsvulster i å vokse, ifølge den spanske undersøkelsen.

I studien ga forskerne THC til mus som hadde kreft, og dette førte til at svulstene vokste saktere, ifølge Reuters.

Når musene fikk i seg stoffet, døde mange av kreftcellene i en prosess som kalles autofagocytose. (...)

Pot may worsen depression, drug czar says
seattletimes.nwsource.com 10.5.2008
WASHINGTON — The White House drug czar warned parents Friday that depressed teens are medicating themselves with marijuana, running risks of deeper depression.

A report by the Office of National Drug Control Policy said that frequent marijuana use doubles a teen's risk of depression and anxiety, based on data compiled from published studies. (...)

Marijuana merits study, doctors group says
seattletimes.nwsource.com 16.2.2008
SACRAMENTO, Calif. — A large and respected association of physicians is calling on the federal government to ease its strict ban on marijuana as medicine and hasten research into the drug's therapeutic uses. (...)

Supporting research into the therapeutic role of marijuana (PDF) (...)

Får lovlig marihuana på automater
vg.no 28.1.2008
(VG Nett) Fra og med i dag kan personer med kroniske lidelser få reseptbelagt marihuana fra automater i den amerikanske delstaten California. (...)

Bipolar Patients on Lithium Show Brain-Tissue Growth
Psychiatr News , 2007;42(10):35) (May 18) (American Psychiatric Association)
Patients on lithium had significant increase in the cingulate and paralimbic regions of the brain, which regulate attention and emotion.

Lithium appears to increase gray matter in the brains of patients who use the drug, according to a report that will appear in Biological Psychiatry in July. (...)

Marihuana bedre enn alkohol?
nrk.no 13.4.2007
Hun er 24 år og ber allmennlege Jørgen Skavlan om et ærlig svar på spørsmålet om marihuana er noe verre for kroppen enn alkohol. Det får hun. (...)

Jørgen Skavlan, spesialist i allmennmedisin
(...) Professor Mørland har også sagt at om samfunnet skulle godkjenne et eneste rusmiddel, burde det være cannabis og ikke alkohol. Det bekrefter jo litt av det du spør om. (...)

Kirsten Dunst: - Verden bedre om alle røykte dop
vg.no 9.4.2007
(VG Nett) Spider-Man-skuespiller Kirsten Dunst sier USAs syn på marihuana er latterlig og at verden ville være et bedre sted dersom alle røyket det narkotiske stoffet. (...)

- Jeg drikker moderat og har prøvd narkotika. Jeg har et annet syn på marihuana enn det USA har, forklarer Dunst.

Hun er kanskje mest kjent for å være den kvinnelige hovedrollen i Spider-Man-filmene og fra filmer som Mona Lisa Smile.

- Jeg har aldri vært noen stor marihuanarøyker, men jeg synes USAs syn på marihuana er latterlig. Jeg mener - er de alvorlige? Verden ville vært et mye bedre sted dersom alle røyket, sier Dunst. (...)

Marijuana-Like Brain Chemicals Ease Parkinson's Symptoms in Mice
healthfinder.gov 7.2.2007
The treatment is much more targeted than smoking marijuana, researchers say.
-- Manipulation of brain molecules similar to those found in marijuana provided dramatic relief of Parkinson's-like symptoms in mice, researchers report.

"This might be a target for treatment that could cure the motor deficits seen in Parkinson's disease," said lead researcher Anatol Kreitzer, whose team published the findings in the Feb. 8 issue of Nature. (...)

TV-skapt forvirring om marihuana
helserevyen.no 27.11.2006
Forbundet Mot Rusgift (FMR) advarer pasienter med diagnosen Multippel Sklerose (MS) mot å blande sammen røyking av marihuana og medisinsk bruk av syntetisk THC. (...)

Skadelig
Han viser til at marihuana, som består av tørkede deler av cannabisplanten, er et tobakksliknende produkt av utseende og inneholder over 400 ulike kjemiske stoffer.

- Dersom man inhalerer marihuanarøyk, får man i seg skadelige stoffer, hvorav noen er rusframkallende. Det finnes ikke noe grunnlag for å forskrive dette produktet som medisin, sier Reinås.

MS-pasienter i Norge kan få spesiell tillatelse til å bruke medikamentet Marinol, som inneholder syntetisk THC. (...)