Pot and Depression: A Little Goes a Long Way
October 25, 2007
(Ivanhoe Newswire)--– That high people get from smoking pot may turn into a low real quick, report Canadian researchers who studied the active ingredient in marijuana in mice.
Their study shows a low dose of the synthetic form of THC works wonders in elevating mouse moods. Higher doses have the exact opposite effect, however, and induce depressive symptoms in the animals.
The investigators explain the finding by noting THC’s effects on the neurotransmitter serotonin. When serotonin levels are low, depression often sets in. Many new drugs to treat depression -- known as SSRIs -- act to increase the level of serotonin in the brain.
In this study, the researchers found serotonin was increased after low doses of THC but dropped like a rock when higher doses were given.
“Low doses had a potent anti-depressant effect, but when we increased the dose, the serotonin in the rats’ brains actually dropped below the level of those in the control group,” study author Gabriella Gobbi, M.D., Ph.D., was quoted as saying. “So, we actually demonstrated a double effect: At low doses it increases serotonin, but at higher doses the effect is devastating, completely reversed.”
So, should people just smoke a little pot to treat depression? The authors point out the pitfalls of that strategy, noting it is difficult to assess what kind of dose people receive from marijuana cigarettes. But they do report the active ingredient in pot may one day point the way to new treatments for depression. The trick will be harnessing the positive aspects of the drug while minimizing unwanted psychotropic effects.
SOURCE: The Journal of Neuroscience, published online Oct. 24, 2007
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