Stereoselectivity of catecholamines: differential effects of cocaine and desipramine on catecholamine-induced contractions of the rat isolated vas deferens.
The effect of uptake inhibitors, cocaine and desipramine, on the contractile response of the rat isolated vas deferens to the enantiomers of noradrenaline and adrenaline and to the corresponding deoxy-derivatives, dopamine and epinephline, was investigated. Cocaine (10(-6)M) significantly potentiated all six agonists; the effect was most marked for the laevo-isomers (-)-noradrenaline and (-)-adrenaline. Desipramine (10(-7) M) also potentiated (-)-noradrenaline, (+)-noradrenaline, (-)-adrenaline, (+)-adrenaline and epinephline but, in contrast, antagonized dopamine. This selective antagonism of dopamine by desipramine was also observed for the separated epididymal and prostatic ends of the rat vas deferens.
D000818:Animals; D002395:Catecholamines / Q000494:pharmacology*; D003042:Cocaine / Q000494:pharmacology*; D003891:Desipramine / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D013237:Stereoisomerism; D014649:Vas Deferens / Q000187:drug effects
D002395:Catecholamines; D003042:Cocaine; D003891:Desipramine