title: [Vasodilatory effects of CNP on aortic arteries of rabbits].
abstract: OBJECTIVE
  To investigate the mechanism of vasodilatory effects of C-type natriuretic peptide (CNP).
  
  
  METHODS
  Tension changes in aortic rings of rabbits were recorded with the presence of CNP or C-type natriuretic peptide receptor (NPR-C) agonist (cANF4-23) after pretreatment with epinephrine (NE) or 60 mmol/L KCl. The vasodilatory effects of four types of potassium channel blocker and NPR-C antagonist (cANF4-28) were also tested.
  
  
  RESULTS
  A maximal vasorelaxant effects of (33.5 +/- 5.9) % and (38.4 +/- 10.6)% were recorded in the presence of 1 micromol/L CNP and cANF4-23, respectively, cANF4-28 attenuated the action of CNP [(19.8 +/- 8.3)%]. The vasorelaxant effects of CNP and cANF4-23 decreased significantly after pretreatment with 60 mmol/L KCl (P < 0.01). Glibenclamide and BaCl2 also attenuated the relaxant activities of CNP (P < 0.05). But only BaClZ decreased the vasodilatory action of cANF4-23 (P < 0.05).
  
  
  CONCLUSIONS
  The relaxant activity of CNP is mediated through three paths: NPR-B/KATP, NPR-C/KIR and NPR-C/calcium channels.
authors.affiliation: Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Li
authors.forename: Qi-yong
authors.initials: QY
authors.lastname: Li
authors.forename: Shi-ping
authors.initials: SP
authors.lastname: Liao
authors.forename: Rong-jian
authors.initials: RJ
authors.lastname: Jiang
authors.forename: Hong
authors.initials: H
authors.lastname: Kong
authors.forename: Jin-chuan
authors.initials: JC
authors.lastname: Lai
authors.forename: Biao
authors.initials: B
authors.lastname: Cheng
authors.forename: Yan
authors.initials: Y
authors.lastname: Shu
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000502:physiology*; D015220:Calcium Channels / Q000187:drug effects; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000502:physiology; D020098:Natriuretic Peptide, C-Type / Q000494:pharmacology*; D024661:Potassium Channels, Inwardly Rectifying / Q000187:drug effects; D011817:Rabbits; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: D015220:Calcium Channels; D024661:Potassium Channels, Inwardly Rectifying; D014665:Vasodilator Agents; D020098:Natriuretic Peptide, C-Type