title: Vasodilatation induced by capsaicin in rat mesenteric vessels is probably independent of nitric oxide synthesis.
abstract: Vasal relaxation induced by capsaicin was investigated on perfused mesenteric vascular bed prepared from Wistar rats. Bolus infusion of capsaicin, from 3.5 to 16 nmol, elicited a dose-dependent vasal relaxation effect, which was antagonized by pretreatment with 3 x 10(-6) M calcitonin gene-related peptide (CGRP) (8-37), an antagonist of CGRP. In order to test whether NO-release is involved in vasorelaxant response to capsaicin, a preparation of mesenteric vascular bed was perfused and superfused for 1 h by N omega-nitro-L-arginine methyl ester (L-NAME) (3 x 10(-3) M), an NO-synthase inhibitor. Vasodilatation induced by capsaicin remained unchanged, while that induced by acetylcholine, used as control, was significantly reduced. The results indicate that in the mesenteric bed, capsaicin-induced vasodilatation is probably independent of the NO-synthesis mechanism and possibly mediated by CGRP.
authors.affiliation: Institute of Pharmacology, Medical School, University of Bari, Italy.
authors.forename: M A
authors.initials: MA
authors.lastname: Potenza
authors.forename: G
authors.initials: G
authors.lastname: De Salvatore
authors.forename: M
authors.initials: M
authors.lastname: Montagnani
authors.forename: M
authors.initials: M
authors.lastname: Serio
authors.forename: D
authors.initials: D
authors.lastname: Mitolo-Chieppa
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000037:antagonists & inhibitors; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology; D002211:Capsaicin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D008297:Male; D019331:NG-Nitroarginine Methyl Ester; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase; D051381:Rats; D017208:Rats, Wistar; D013152:Splanchnic Circulation / Q000187:drug effects*; D014664:Vasodilation / Q000187:drug effects*
chemical_list: D009569:Nitric Oxide; D001120:Arginine; D019001:Nitric Oxide Synthase; D000594:Amino Acid Oxidoreductases; D015740:Calcitonin Gene-Related Peptide; D002211:Capsaicin; D019331:NG-Nitroarginine Methyl Ester