Posted by undopaminergic on May 24, 2008, at 16:21:48
In reply to Re: Sulpiride and Abilify questions... » undopaminergic, posted by SLS on May 23, 2008, at 16:21:27
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> Why is D1 so important to mood illnesses? I should think that D2 and D3 are more important, as they facilitate the activities of limbic structures, primarily, the nucleus accumbens. Reward, motivation, and all of that stuff.
>At least some dopamine actions in that region require the simultaneous activation of both D1- and D2-receptor subtypes. Drugs that accomplish that, typically by enhancing the production or release of DA - such as cocaine, heroin, or L-dopa - generally produce effects that are more desirable - especially subjectively - than do synthetic direct agonists or partial agonists.
> Apomorphine, an unselective DA receptor agonist (including D1), does not appear to have antidepressant properties.
>On the other hand, the fact that apomorphine remains in use despite its unfavourable technical properties - such as a short half-life and the necessity to administer it by injection - suggests that it is superior to alternatives in other respects, including a more complete or natural receptor binding profile.
> The key might not be which DA receptors are affected, but in what tracts they are affected.
>The place is indeed of significance. The relative importance of different types of receptors may also vary between regions.
poster:undopaminergic
thread:829749
URL: http://www.dr-bob.org/babble/neuro/20080418/msgs/830915.html