title: [Regulatory effects of nucleotides on ATP-sensitive potassium channel opener pinacidil-induced vascular relaxation].
abstract: OBJECTIVE
  In order to evaluate the regulatory effects of nucleotides and adenosine on ATP-sensitive potassium channel (K(ATP)) in artery smooth muscles, the effects of them on vascular relaxation induced by K(ATP) opener pinacidil(Pin) were investigated.
  
  
  METHODS
  The isolated endothelium- denuded aorta rings were preincubated with nucleotides or nucleotides and glibenclamide (Gli) for 10 min, the vascular relaxation induced by Pin in aorta precontracted with 20 mmol x L(-1) KCl was observed.
  
  
  RESULTS
  After the isolated endothelium-denuded aorta rings were preincubated with ATP, ADP, UDP, GTP and adenosine (Ade) 100 micromol x L(-1) respectively, the vascular relaxation induced by Pin was changed as following: (1) ATP could inhibit the K(ATP) activation by Pin and enhance the blockade of K(ATP) by Gli. (2) ADP could inhibit the K(ATP) activation by Pin and attenuate the blockade of K(ATP) by Gli. (3) The regulatory effect of Ade on K(ATP) was similar with that of ADP. (4) UDP could enhance the K(ATP) activation by Pin and attenuate the blockade of K(ATP) by Gli. (5) GTP could enhance the K(ATP) activation by Pin, but had no effects on the blockade of K(ATP) by Gli.
  
  
  CONCLUSIONS
  Nucleotides and adenosine, related to energy metabolism, could modulate the functions of K(ATP) in vascular smooth muscle. But their pharmacological characteristics were different.
authors.affiliation: Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing 100850, China.
authors.forename: Hua-mei
authors.initials: HM
authors.lastname: He
authors.forename: Chao-liang
authors.initials: CL
authors.lastname: Long
authors.forename: Hai
authors.initials: H
authors.lastname: Wang
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology / Q000187:drug effects*; D005905:Glyburide / Q000494:pharmacology*; D066298:In Vitro Techniques; D054086:KATP Channels / Q000378:metabolism*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D009711:Nucleotides / Q000494:pharmacology*; D020110:Pinacidil / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D054086:KATP Channels; D009711:Nucleotides; D014665:Vasodilator Agents; D020110:Pinacidil; D005905:Glyburide