Pharmacology - opiates, dopamine, and their relationship

[Politicalchalk]

Not sure if I've done this in the preferred method, but in the pharmacology board, a discussion about the above mentioned has come up, and I was hoping someone with serious opiate knowledge could give some input.

Here's the link:
http://www.drugs-forum.com/forum/showthread.php?t=64634

Thanks

[y0ssarianlives]

Interesting article here. Shitty webpage, but the reading is sound.

http://www.macalester.edu/psychology...e/opioids.html

Basically, there seems to be evidence based on experiments with lab rats that suggests opioid use reduces a certain kind of inhibition of dopamine release in one of the part of the brain that opioids act on, which results in increased stimulation of dopaminergic neurons in that same area.

The study also suggests that the effects of opioids are not contingent on the dopaminergic activity, but they are linked in one form or another.

So in a short summary, opioid use has a small impact on dopamine, which makes sense as dopamine is pretty much the "reward" neurotransmitter, and SWIM will be damned if opioids/opiates aren't extremely rewarding. But, when dopamine antagonists were administered to these rats before opioid use, they found that rats would still trigger the opioid stimulus, not at as increased a level as without the antagonist, but it still was definitely active.

I'm not a nuerochemist and did not grasp some of the terminology used in referring to some of the real nitty gritty going-ons in the brain, but the article is definitely understandable.

Hope this sates your curiousity somewhat