Posted by Dopamine123 on June 30, 2008, at 18:11:45
In reply to Re: Didn't like Requip » Dopamine123, posted by satsumas on June 30, 2008, at 16:51:45
>i'm curious as to what your specific experience with mirapex was, how you noticed the cog. disfunction kicking in, and what specific aspects of your experience you felt were hit the most.
First, my concentration got really bad. I also found that my verbal fluency and overall ability to talk decreased considerably. It was like I couldn't think of anything to say when being around people. I just became very untalkative and quiet. Also my motivation levels took a hit.
I did notice a mild increase in the pleasure response, but I felt somewhat demented due to the executive dysfunction. The pleasure response rapidly dissappeared too probably due to tolerance. I actually found women more attractive which is probably due to agonism of d2/d3 receptors in the pleasure center.
So it was kind of weird. It decreased my apathy in certain instances, but seemed to increase it in regards to other aspects of functioning.
I take adderall now. This drug is much more consistent in improving apathy, verbal fluency, motivation and anhedonia. Probably because it stimulates D1, D2, and D3 receptors at the same time.
>why would d2/d3 agonists lower d1? and what does d1 do?
Mirapex is like fake dopamine. It increases activation at d2/d3 receptors, but it isn't an agonist at d1 receptors. It also hits d2/d3 autoreceptors that control the synthesis and release of dopamine. So what happens is that the amount of real dopamine in the synapse actually decrease because it is hitting those autoreceptors. The autoreceptors are like feedback mechanism in your brain to make sure you don't get too much dopamine. So your d2/d3 receptors end up getting activated to a greater degree because of mirapex, however the amount of real dopamine decreases. Your brain thinks there is an overload of dopamine so it compensates by reducing output. However while mirapex stimulates d2/d3 receptors it doesn't stimulate the d1 receptor. So the d1 receptor is activated less than it normally would because there is less dopamine.
Sorry if that's confusing, that's the best I can do.
Activation of the D1 receptor is associated with cognitive functioning, verbal fluency, interest (as opposed to apathy).
It's complex and you might not necessarily get the same response that I did. I think it all depends on your original brain functioning.
As cactus said
"wow, I had the opposite response. I posted a more detailed response up higher on the board. It was good and bad for me"
poster:Dopamine123
thread:834964
URL: http://www.dr-bob.org/babble/20080626/msgs/837378.html