title: [Vasodilating effect of capsaicin on rat mesenteric artery and its mechanism].
abstract: To investigate the vasodilating effect of capsaicin (CAP) on rat mesenteric artery and its mechanism.
  
  
  
  The third branch of the superior mesenteric artery in male Sprague-Dawley rat (250-350 g) was excised, the periadventitial fat and connective tissue were removed and the mesenteric artery was dissected into 2 mm rings. Each ring was placed in a 5 ml organ bath of DMT 610M system and the tension was recorded.
  
  
  
  CAP (10(-9)-10(-5) mol/L) relaxed endothelium-intact and endothelium-denuded mesenteric artery pre-constricted by phenylephrine (10(-5) mol/L), and the vasodilation in endothelium-intact mesenteric artery was stronger than that in endothelium-denuded one. Pretreatment with either L-NAME (3 X10(-4) mol/L), an inhibitor of nitric oxide synthase(NOS), or CGRP8-37 (2 X 10(-6) mol/L), an antagonist of calcitonin gene-related peptide (CGRP), for 30 min significantly attenuated the relaxation of endothelium-intact mesenteric artery induced by CAP. CGRP (10(-10)-3 X10(-8) mol/L) relaxed endothelium-intact and endothelium-denuded mesenteric artery pre-constricted by phenylephrine, and the vasodilation in endothelium-intact mesenteric artery was stronger than that in endothelium-denuded one. Substance P did not relax the mesenteric artery pre-constricted by phenylephrine.
  
  
  
  CAP has partial endothelium-dependent relaxation effect on rat mesenteric artery, which may be mediated by activating the endothelial NOS-NO pathway. The endothelium-independent relaxation in rat mesenteric artery induced by CAP may be mediated by CGRP.
authors.affiliation: Department of Cardiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Chen
authors.forename: Huanhuan
authors.initials: H
authors.lastname: Zhu
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Lihong
authors.initials: L
authors.lastname: Wang
authors.forename: Liangrong
authors.initials: L
authors.lastname: Zheng
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D002211:Capsaicin / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects* / Q000502:physiology; D010446:Peptide Fragments / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014664:Vasodilation / Q000187:drug effects*
chemical_list: D010446:Peptide Fragments; C058636:calcitonin gene-related peptide (8-37); D015740:Calcitonin Gene-Related Peptide; D002211:Capsaicin