Actions of dopamine and related amines on reserpinized and chronically denervated vasa deferentia of the rat.
1. Reserpine, chronic guanethidine denervation and alpha-adrenoceptor antagonists were used to distinguish between presynaptic and postsynaptic actions of exogenous dopamine (DA), octopamine (OA), tyramine (TA) and noradrenaline (NA) on the rat vas deferens. 2. TA has only a presynaptic action while DA and OA have mixed presynaptic actions (releasing endogenous NA) and postsynaptic actions. 3. The postsynaptic actions of DA and OA are likely to be mediated by alpha-adrenoceptors rather than by specific receptors.
D000588:Amines / Q000494:pharmacology*; D000818:Animals; D003714:Denervation; D004298:Dopamine / Q000494:pharmacology*; D006145:Guanethidine / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D008787:Metoclopramide / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D009638:Norepinephrine / Q000494:pharmacology; D009655:Octopamine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012110:Reserpine / Q000494:pharmacology*; D014439:Tyramine / Q000494:pharmacology; D014649:Vas Deferens / Q000187:drug effects / Q000294:innervation
D000588:Amines; D009655:Octopamine; D012110:Reserpine; C028435:2-octopamine; D008787:Metoclopramide; D004298:Dopamine; D009638:Norepinephrine; D014439:Tyramine; D006145:Guanethidine