Posted by anonymoose on December 3, 2007, at 22:36:49
In reply to Re: dopa antag, and 5-ht antag, posted by B2chica on December 3, 2007, at 13:12:09
> found this....about the 5-HT2A receptor...i think answering my question as to why the componenets of olanzapine actually help rather than hinder my depression.
>
> "Increased stimulation of 5-HT2A receptors seem to oppose the therapeutic actions of increased stimulation of other serotonin receptors in anti-depressant and anxiolytic treatments."5-HT2a is a main excitatory serotonin receptor, and stimulation (or *agonism*) of it triggers neuronal excitation and anxiety, among other things.
5-HT2a blockade, or *antagonism*, decreases anxiety.
I'm not too sure about olanzapine, but I thought it was an antagonist at 2a and 2c sites. The 2c antagonism, specifically, is what is implicated in weight gain. (Same with mirtazapine.)
Are you taking olanzapine or the olanzapine-fluoxetine combination (Symbayax?)
When SSRIs increase synaptic serotonin, one undesired consequence is increased stimulation of the 2a/2c receptors. This increased stimulation of excitatory serotonin receptors is what's implicated in SSRIs' paradoxical effect of actually increasing anxiety and suicide risk within the first few weeks. It's not until the 2a/2c receptors start to downregulate/desensitize that anxiolytic effects are felt.
poster:anonymoose
thread:797644
URL: http://www.dr-bob.org/babble/20071125/msgs/798638.html