Posted by zeugma on November 21, 2006, at 5:06:24
In reply to Re: changes in NMDA receptor function, posted by linkadge on November 20, 2006, at 15:22:22
> There is a slight difference. The neurotrophic theory of antidepressants is that hippocampal neurogenesis is critical for clinical improvement, ie the drug must grow new brain cells to work.
>
> The NMDA receptor adaptation theory says that after repeated exposure to antidepressants there is a regional dampening of glutamatergic function. Ie the drug tames overactive limbic activity which may be present in neurotic types of depression.>>Another facet of this theory is that there is a reciprocal enhancement of AMPA function: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=16442080
One difference between AMPA and NMDA receptors, which may be relevant for their AD and anti-AD actions, is their different effects on ion channels: NMDA stimulation stimulates Ca2+ phosphorylation while AMPA receptors stimulate K+ phosphorylation: this would result in a net decrease and increase in monoaminergic transmission respectively.
-z
poster:zeugma
thread:704599
URL: http://www.dr-bob.org/babble/20061117/msgs/705737.html