title: Role of vascular K(ATP) channels in blood pressure variability after sinoaortic denervation in rats.
abstract: OBJECTIVE
  To investigate the role of ATP-sensitive potassium (K(ATP)) channels on blood pressure variability (BPV) in sinoaortic denervated (SAD) rats.
  
  
  METHODS
  SAD was performed on male Sprague-Dawley rats 4 weeks before the study. mRNA expression of Kir6.1, Kir6.2 and SUR2 in aorta and mesenteric artery was determined using real-time quantitative polymerase chain reaction, and confirmed at the protein level using Western blotting and laser confocal immunofluorescence assays. Concentration-response curves of isolated aortic and mesenteric arterial rings to adenosine and pinacidil were established. Effects of K(ATP) channel openers and blocker on BPV were examined in conscious SAD rats.
  
  
  RESULTS
  Aortic SUR2 expression was significantly greater, while Kir6.1 was lower, in SAD rats than in sham-operated controls. In contrast, in the mesenteric artery both SUR2 and Kir6.1 expression were markedly lower in SAD rats than controls. For both arteries, Kir6.2 expression was indistinguishable between sham-operated and SAD rats. These findings were confirmed at the protein level. Responses of the aorta to both adenosine and pinacidil were enhanced after SAD, while the mesenteric response to adenosine was attenuated. Pinacidil, diazoxide, nicorandil, and glibenclamide significantly decreased BPV.
  
  
  CONCLUSIONS
  These findings indicate that expression of vascular K(ATP) channels is altered by chronic SAD. These alterations influence vascular reactivity, and may play a role in the increased BPV in chronic SAD rats.
authors.affiliation: Department of Pharmacology, School of Pharmacy, Second Military Medical University, Shanghai, China.
authors.forename: Zhong-wei
authors.initials: ZW
authors.lastname: Yang
authors.forename: Dong-jie
authors.initials: DJ
authors.lastname: Li
authors.forename: Chong
authors.initials: C
authors.lastname: Liu
authors.forename: Ping
authors.initials: P
authors.lastname: Han
authors.forename: Yi-li
authors.initials: YL
authors.lastname: Yang
authors.forename: Ding-feng
authors.initials: DF
authors.lastname: Su
authors.forename: Fu-ming
authors.initials: FM
authors.lastname: Shen
mesh_terms: D000241:Adenosine / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000293:injuries / Q000378:metabolism; D017763:Autonomic Denervation; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D015153:Blotting, Western; D002346:Carotid Sinus / Q000294:innervation; D004305:Dose-Response Relationship, Drug; D054086:KATP Channels / Q000378:metabolism*; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects / Q000378:metabolism; D020110:Pinacidil / Q000008:administration & dosage / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D054086:KATP Channels; D012333:RNA, Messenger; D014665:Vasodilator Agents; D020110:Pinacidil; D000241:Adenosine