Posted by MB on May 31, 2003, at 19:43:41
In reply to Re: Alchohol isn't really a depresant , posted by Tony P on May 30, 2003, at 9:36:47
> Alcohol also has a dopaminergic effect I believe, leading to the mood-elevation that makes it confusing when it is called a depressant.
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And more confusing is the fact that dopamine evokes an inhibitory post synaptic response in the nucleus accumbens (i.e., dopamine decreases the firing rate of neurons originating from the "feel good" nucleus by stepping down adenyl cyclase production in the cell). So, "depressing" that particular brain region has "antidepressant" effects (or, at least, euphorogenic effects). Very, very confusing. Most people think that increased firing rate of the accumbal neurons = pleasure, but it is the opposite. This is the basis for one theory on why benzos and barbituates are reinforcing despite being depressants: by potentiating the effects of GABA receptors in this area, they too reduce the firing rate of accumbal neurons.
MB
poster:MB
thread:229599
URL: http://www.dr-bob.org/babble/20030530/msgs/230476.html