Possible involvement of nitric oxide in pilocarpine induced seminal emission in rats.
Intraperitoneal injection of pilocarpine (0.75-3.0 mg/kg) caused a dose-related seminal emission in adult male rats. The seminal emission response to 3 mg/kg of pilocarpine was greatly reduced in atropinized (5 and 10 mg/kg, SC) animals, suggesting a cholinomimetic effect. Nw-nitro-L-arginine methyl ester (5, 10, and 20 mg/kg, SC), a nitric oxide synthesis inhibitor, also inhibited the pilocarpine-induced seminal emission, which was reversed by L-arginine (600 mg/kg, SC) or by coinjection of sodium nitroprusside (0.5 mg/kg, SC). Urine analysis for levels of nitric oxide metabolites, nitrate/nitrite (NO3-/NO2-), showed marked alterations in accordance with the drug treatments. The results suggest that nitric oxide mediates the inhibitory neurotransmission responsible for seminal emission in pilocarpine stimulated rats.
Tomé
A R
AR
Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil.
da Silva
J C
JC
Souza
A A
AA
Mattos
J P
JP
Vale
M R
MR
Rao
V S
VS
D000818:Animals; D001120:Arginine / Q000494:pharmacology; D001285:Atropine / Q000494:pharmacology; D008297:Male; D018721:Muscarinic Agonists / Q000494:pharmacology*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009566:Nitrates / Q000652:urine; D009569:Nitric Oxide / Q000502:physiology*; D009573:Nitrites / Q000652:urine; D009599:Nitroprusside / Q000494:pharmacology; D010862:Pilocarpine / Q000494:pharmacology*; D011301:Preoptic Area / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012661:Semen / Q000187:drug effects*
D018721:Muscarinic Agonists; D009566:Nitrates; D009573:Nitrites; D010862:Pilocarpine; D009599:Nitroprusside; D009569:Nitric Oxide; D001285:Atropine; D001120:Arginine; D019331:NG-Nitroarginine Methyl Ester