Posted by karaS on October 24, 2004, at 15:39:58
In reply to Re: MAOIs decrease density of DA receptors- KaraS » Kristel, posted by King Vultan on October 24, 2004, at 10:28:13
> > > Todd,
> > >
> > > Thought you might like to see this abstract which seems to confirm what you've been saying. Here's the key sentence from it:
> > >
> > > "MAOI antidepressants induced a decrease in the density of both D1-like and D2-like DA receptors."
> > >
> > > Here's the link:
> > >
> > > http://www.chocolate.org/peadep.htm
> > >
> > > Kara
> >
> > And that is a negative thing to happen ?!!
> >
> > In fact the opposite might be true. Decrease in receptos density mean down-regulation which is thought of as the anti-depressant mechanism of these drugs. Decrease in density means increase in sensitivity of the receptors.
>
>
> No, decreasing density is the same as reducing sensitivity; hypersensitivity implies that there are many more receptors than are ideal in a particular area. Downregulation decreases sensitivity by reducing the number of receptors.
>
> Be that as it may, the abstract is interesting, but I don't know enough about dopamine receptors to come to any firm conclusions myself. I was aware that phenylethylamine is a classic MAO-B substrate, which is one of the reasons behind chocolate appearing on some of the "Do not eat" lists for MAOI patients (PEA has been called the "chocolate amphetamine"). Inhibiting MAO-B as do the older MAOIs--and as selegiline does, as well--does increase PEA levels, and there appears to be at least a possibility that there may be some therapeutic benefits from this.
>
> ToddTodd,
If I read the abstract correctly, then the MAOI phenelzine was able to decrease density of D1 and D2 while selegiline was only able to decrease density of D1.I'm thinking that I should be trying an MAOI now.
I think that my dopamine autoreceptor problem is a recent one (though I've suffered from depression for almost 30 years). The reason I say this is because I've only recently, within the last couple of years, gotten tired from exercising. It's not a fatigue that happens when I exercise. It's an hour or two later that I want to go to sleep. I had entertained the idea that it was an adrenal problem but I feel fine while exercising and shortly afterwards. I'm convinced now that the exercise boosts dopamine and then a while later (because of the DA receptors), I need to go to sleep.
Then I'm left with why this has happened to me now. It could be that long term CFS has finally done this to me (per Dr. Jay Goldstein's theory) or possibly long-term SSRI usage. The latter also makes me question whether Cymbalta is a good medication for me now.
Kara
poster:karaS
thread:406550
URL: http://www.dr-bob.org/babble/20041024/msgs/406691.html