Posted by undopaminergic on January 1, 2023, at 10:33:00
In reply to Re: Tentative remission on ketamine » undopaminergic, posted by SLS on December 31, 2022, at 17:28:38
> Hi, UD.
>
> > In my view, NMDA-glutamatergic receptor antagonists, like ketamine or memantine, enhance the *functional* dopaminergic tone, without necessarily elevating dopamine concentrations at all.
>
> What is "dopaminergic tone"?
>Tonic is in contrast to phasic. I meant it, approximately, as the dopaminergic "background" or "baseline" signal. It adapts to stimuli slowly, but is sustained. Phasic signals react fast, but are also more ephemeral.
> How does blocking NMDA receptors result in increased dopaminergic tone?
>I think it is about the balance between dopamine and glutamate. Increasing dopamine would affect the balance similarly to decreasing glutamate. It's just my theory, though, so you probably shouldn't quote me on it.
> Thanks.
>
> I am clueless as to what NMDA receptors are all about, other than their endogenous ligand is glutamate.
>NMDA receptors are ligand-gated ion channels. When activated, they are permeable to Ca2+ ions. They are named after the excitatory amino acid N-methyl-D-aspartate that binds selectively to these channels.
-undopaminergic
poster:undopaminergic
thread:1121402
URL: http://www.dr-bob.org/babble/20220917/msgs/1121441.html