title: Differential blockade of ATP, noradrenaline and electrically evoked contractions of the rat vas deferens by nifedipine.
abstract: Nifedipine has recently been found to block electrically induced contractions of the prostatic portion of the vas deferens. The present results show that nifedipine blocks contractile responses to ATP in the parallel with the nerve mediated response, whereas the rapid phasic contractile response to noradrenaline is unaffected. The slower, tonic contractions to noradrenaline are blocked most easily, when the nerve-mediated responses are unchanged. These findings support the view that neurally released ATP may contribute to contractile responses of the vas.
mesh_terms: D000255:Adenosine Triphosphate / Q000037:antagonists & inhibitors*; D000818:Animals; D004558:Electric Stimulation; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D009543:Nifedipine / Q000494:pharmacology*; D009638:Norepinephrine / Q000037:antagonists & inhibitors*; D011725:Pyridines / Q000494:pharmacology*; D051381:Rats; D013997:Time Factors; D014649:Vas Deferens / Q000187:drug effects
chemical_list: D011725:Pyridines; D000255:Adenosine Triphosphate; D009543:Nifedipine; D009638:Norepinephrine