Archive for the ‘Depression’ Category

Some studies suggest that cannabis use is associated with suicidal ideation, but no detailed longitudinal study has examined suicide as an outcome. AIMS: To examine the association between cannabis use and completed suicide. METHOD: A longitudinal study investigated 50 087 men conscripted for Swedish military service, with cannabis use measured non-anonymously at conscription. Suicides during 33 years of follow-up were identified by linkage with the National Cause of Death Register. RESULTS: There were 600 (1.2% of cohort) suicides or deaths from undetermined causes. Cannabis use was associated with an increased risk of suicide (crude OR for ‘ever use’ 1.62, 95% CI 1.28-2.07), but this association was eliminated after adjustment for confounding (adjusted OR = 0.88, 95% CI 0.65-1.20). CONCLUSIONS: Although there was a strong association between cannabis use and suicide, this was explained by markers of psychological and behavioural problems. These results suggest that cannabis use is unlikely to have a strong effect on risk of completed suicide, either directly or as a consequence of mental health problems secondary to its use.

Cannabidiol (CBD) is a non-psychotomimetic compound from Cannabis sativa that induces anxiolytic- and antipsychotic-like effects in animal models. Effects of CBD may be mediated by the activation of 5-HT(1A) receptors. As 5-HT(1A) receptor activation may induce antidepressant-like effects, the aim of this work was to test the hypothesis that CBD would have antidepressant-like activity in mice as assessed by the forced swimming test. We also investigated if these responses depended on the activation of 5-HT(1A) receptors and on hippocampal expression of brain-derived neurotrophic factor (BDNF). EXPERIMENTAL APPROACH: Male Swiss mice were given (i.p.) CBD (3, 10, 30, 100 mg*kg(-1)), imipramine (30 mg*kg(-1)) or vehicle and were submitted to the forced swimming test or to an open field arena, 30 min later. An additional group received WAY100635 (0.1 mg*kg(-1), i.p.), a 5-HT(1A) receptor antagonist, before CBD (30 mg*kg(-1)) and assessment by the forced swimming test. BDNF protein levels were measured in the hippocampus of another group of mice treated with CBD (30 mg*kg(-1)) and submitted to the forced swimming test. KEY