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IACM-Bulletin of April 6, 2014

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Science — The legalization of medical cannabis causes no increase in crime and may reduce some violent crime

The legalization of cannabis for medicinal purposes causes no increase in crime, according to a new study. In fact, legalized medical cannabis may reduce some violent crime, including homicide, University of Texas at Dallas researchers wrote in the journal Plos One. "We believe that medical marijuana legalization poses no threat of increased violent crime," Robert Morris, the study's lead author, told journalists.

Morris, associate professor of criminology and his colleagues looked at crime rates for all 50 U.S. states from 1990 to 2006. During this period, 11 states legalized medical cannabis. The researchers examined legalization's effect on what the FBI calls Part I crimes, which include homicide, rape, robbery, aggravated assault, burglary, larceny and auto theft. "After controlling for a host of known factors related to changes in crime rates -- we accounted for factors such as poverty, employment, education, even per capita beer sales, among other things -- we found no evidence of increases in any of these crimes for states after legalizing marijuana for medical use," Morris said. "In fact, for some forms of violence -- homicide and assault -- we found partial support for declines after the passing of this legislation." Other research suggests that alcohol is a significant factor when it comes to violent crime.

Morris RG, Teneyck M, Barnes JC, Kovandzic TV. The effect of medical marijuana laws on crime: evidence from state panel data, 1990-2006. PLoS One 2014;9(3):e92816.

Huffington Post of 27 March 2014.

News in brief

Science/Human — Certain variants of the CB1 receptor are associated with increased happiness

Individuals with high subjective happiness level, rate their current affective states more positively when they experience positive events. In an experiment 198 healthy volunteers were used to compare the subjective happiness level between two variants of the cannabinoid 1 receptor. The so-called cytosine allele carriers of the CB1 receptor gene exhibited a greater magnitude of positive emotions when they experienced positive events and had a higher subjective happiness level.

Department of Health and Psychosocial Medicine, Aichi Medical University School of Medicine, Japan.

Matsunaga M, et al. PLoS One. 2014;9(4):e93771.

USA — Majority wants to treat, not jail, drug users: survey finds

About two-thirds of US citizens say drug users need access to treatment to address their addiction rather than criminal prosecution that could lead to jail time, according to a poll by Pew Research Center released on 2 April. Among the 1,821 U.S. adults polled, 67 percent said they backed treatment for drug users compared to 26 percent who said the government should focus on prosecution. Another 7 percent said they did not know what to focus on. The survey also found that 75 percent of respondents think that the sale and use of cannabis will be legal nationwide in the future.

Reuters of 2 April 2014.

Associated Press of 2 April 2014.

Canada — Court rules that patients can continue to grow cannabis

Federal Court Judge Michael Manson ruled patients with licenses to grow cannabis for their own use could continue producing the drug despite new regulations that will ban the practice from 1 April on. Manson granted an application seeking to preserve the status quo until medical cannabis patients could challenge the new system in court. The government agency Health Canada said it will ask the Federal Court of Appeal to overturn the injunction. Thousands of Canadians have licenses to grow their own cannabis for personal use. The government plans to allow only select commercial producers to grow cannabis.

UPI of 31 March 2014.

UK — Plans for per se limits for THC in blood

According to plans of the government British drivers will be permitted to drive with low levels of illegal drugs in their blood from late 2014 on. The new laws cover blood-content limits for 16 different drugs. The limit for THC will be set at 2 µg/L (=2 ng/ml) in whole blood. According to an expert meeting at the German Fed¬er¬al High¬way Re¬search In¬sti¬tute (Bundesanstalt fuer Strassenwesen) near Cologne, Germany, on 24 October 2013 the Netherlands plan a limit of 5 ng of THC in 1 ml of blood plasma (which is about 3,1 ng/ml whole blood) and Norway a limit of 3 ng/ml (about 1,9 ng/ml whole blood).

Motoring.com.au of 1 April 2014.

Science/Human — Abstinence from cannabis associated with increases in alcohol and tobacco use

During a two-week voluntary cannabis abstinence and at one-month follow-up in 45 cannabis users abstaining from cannabis was associated with increases in alcohol and tobacco use that decreased with resumption of cannabis use; however there were no increases in individuals who remained abstinent from cannabis at one-month follow-up. Tobacco use did not increase in those experiencing milder cannabis withdrawal symptoms.

School of Psychology, University of Sydney, Australia.

Allsop DJ, et al. Drug Alcohol Depend. 2014 Feb 12. [in press]

Science/Animal — Fasting and exercise increased THC-COOH levels in rats

Rats given THC for 5 days followed by a 4-day washout showed elevated blood plasma THC-COOH levels when fasted for 24 h relative to non-fasted animals. Rats pre-treated with THC and exercised 20 h later also showed elevated plasma THC-COOH. Authors concluded that their results “confirm that fasting and exercise can increase plasma cannabinoid levels”.

The Discipline of Pharmacology, The University of Sydney, Australia.

Wong A, et al. Psychopharmacology (Berl). 2014 Apr 3 [in press]

Science/Human — Fasting and exercise did not increase THC-COOH levels in humans

Six daily cannabis users (with a mean body mass index of 20.8 as a sign of low body fat) were exposed to a 45-min. moderate-intensity workout and a 24-hr period of food deprivation. There were no major differences in the measured THC-COOH levels in serum or urine before and after physical exercise or food deprivation. Authors concluded “that exercise and/or food deprivation are unlikely to cause sufficient cannabinoid concentration changes to hamper correct interpretations in drug testing programmes.”

Department of Clinical Pharmacology, St. Olav University Hospital, Trondheim, Norway.

Westin AA, et al. Basic Clin Pharmacol Toxicol. 2014 Mar 27. [in press]

Science/Animal — Antidepressants change concentrations of endocannabinoids in the brain

Chronic administration of different antidepressants (imipramine, escitalopram, tianeptine) all increased the levels of the endocannabinoid anandamide in a certain brain region (hippocampus) and also increased both anandamide and 2-AG levels in the dorsal striatum. Authors wrote that the endocannabinoid system “appears to play a significant role in the mechanism of action of clinically effective and potential antidepressants and may serve as a target for drug design and discovery.”

Department of Toxicology, Faculty of Pharmacy, Jagiellonian University, Poland.

Smaga I, et al. Neurotox Res. 2014 Mar 21. [in press]

Science/Human — Enzymes, which degrade endocannabinoids, are increased in spinocerebellar ataxias

Spinocerebellar ataxias are characterized by a loss of balance and motor coordination due to degeneration of the cerebellum. After death the brains of patients affected by the diseases were investigated and degradative endocannabinoid enzymes (FAAH, MAGL) were significantly increased in the cerebellum. Authors wrote that this “would presumably lead to reduced endocannabinoid levels.”

Instituto Universitario de Investigación en Neuroquímica, Universidad Complutense, Madrid, Spain.

Rodríguez-Cueto C, et al. Pathobiology 2014;81(3):149-159.

Science/Human — Two medications were effective in the treatment of cannabis use disorders in psychotic patients

Thirty patients with schizophrenia and cannabis abuse or dependence received either ziprasidone or clozapine and were followed up for up to 12 months. Cannabis use was reduced in both groups during follow-up.

Department of Psychiatry and Psychotherapy, University Hospital of Cologne, Germany.

Schnell T, et al. Am J Addict. 2014 Mar 15. [in press]

Science/Animal — An extract of the plant Melilotus exerts anti-inflammatory effects by increasing CB2 receptor activity

In rats with lung inflammation an extract of Melilotus Suaveolens Ledeb reduced inflammation and this effect was associated with an up-regulating of CB2 receptors. Melilotus is a plant belonging to the family of Fabaceae (bean family).

The First Hospital Affiliated To Kunming Medical University, China.

Liu MW, et al. BMC Complement Altern Med 2014;14:94.