Evidence for involvement of nitric oxide (NO) or a related nitroso-compound in NANC inhibitory neurotransmission in the pigeon oesophageal smooth muscle.
In the pigeon oesophageal smooth muscle electrical field stimulation (EFS), in the presence of atropine and guanethidine, evoked TTX-sensitive inhibitory effects on both the electrical and mechanical activity. N(omega)-Nitro L-arginine (L-NA) (0.1-100 microM), an inhibitor of nitric oxide synthase, reduced the inhibitory EFS-evoked effects. Sodium nitroprusside (SNP) (10 microM), a NO-donor, mimicked the effects evoked by EFS. Apamin (1 microM) perfusion did not modify the inhibitory effects induced by SNP. Cystamine (10 microM), a guanylate-cyclase inhibitor, reduced the inhibitory effects elicited by EFS. This study shows a possible role for NO in the non-adrenergic non-cholinergic (NANC) inhibitory responses induced by EFS in the pigeon oesophagus.
Postorino
A
A
Dipartimento di Biologia cellulare e dello Sviluppo, Laboratorio di Fisiologia generale, Palermo, Italia.
Vetri
T
T
Bonvissuto
F
F
Fileccia
R
R
Urso
S A
SA
D018663:Adrenergic Agents / Q000494:pharmacology; D000818:Animals; D001030:Apamin / Q000494:pharmacology; D001285:Atropine / Q000494:pharmacology*; D010856:Columbidae; D003538:Cystamine / Q000494:pharmacology; D004558:Electric Stimulation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004947:Esophagus / Q000502:physiology*; D006145:Guanethidine / Q000494:pharmacology*; D066298:In Vitro Techniques; D018727:Muscarinic Antagonists / Q000494:pharmacology; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D009433:Neural Inhibition / Q000187:drug effects* / Q000502:physiology; D018377:Neurotransmitter Agents / Q000502:physiology; D009569:Nitric Oxide / Q000502:physiology*; D019335:Nitroarginine / Q000494:pharmacology*; D009599:Nitroprusside / Q000494:pharmacology*
D018663:Adrenergic Agents; D004791:Enzyme Inhibitors; D018727:Muscarinic Antagonists; D018377:Neurotransmitter Agents; D009599:Nitroprusside; D019335:Nitroarginine; D001030:Apamin; D009569:Nitric Oxide; D001285:Atropine; D003538:Cystamine; D006145:Guanethidine