Evidence for participation of nitric oxide in excitatory neurotransmission in rat vas deferens.
A depression of the fast, non-adrenergic, and also of the slow, adrenergic, components of muscle contraction in response to intramural nerve stimulation was induced by the blocker of nitric oxide synthase NG-nitro-L-arginine methyl ester (L-NAME), in rat vas deferens. Effects of exogenous noradrenaline or ATP were not reduced by L-NAME. However, L-arginine also caused an inhibition of electrically induced effects in most of the preparations, contrary to the expectations for a precursor of nitric oxide synthesis. In spite of these difficulties L-arginine antagonized the action of L-NAME. These results indicate that nitric oxide is involved in excitatory nerve-muscle transmission in vas deferens.
Vladimirova
I
I
Department of Pharmacology, Escola Paulista de Medicina, São Paulo, Brazil.
Jurkiewicz
N H
NH
Jurkiewicz
A
A
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D019331:NG-Nitroarginine Methyl Ester; D009469:Neuromuscular Junction / Q000187:drug effects / Q000502:physiology; D009569:Nitric Oxide / Q000502:physiology*; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*; D014649:Vas Deferens / Q000294:innervation*
D009569:Nitric Oxide; D000255:Adenosine Triphosphate; D001120:Arginine; D019331:NG-Nitroarginine Methyl Ester; D009638:Norepinephrine