The mechanisms of peroxynitrite-induced relaxations in isolated rat anococcygeus muscle

Pharmacology. 2002 Sep;66(1):1-4. doi: 10.1159/000065311.

Abstract

We have previously reported that peroxynitrite (ONOO(-)) caused relaxations on isolated rat anococcygeus muscle and in the present study the possible mechanisms of the relaxant effect were investigated. ONOO(-) (0.03- 1.0 mmol/l)-induced relaxations were reduced significantly by the presence of an ATP-sensitive potassium channel (K(+)(ATP) channel) blocker, glibenclamide (0.3 micromol/l), or 1H-(1,2,4)oxadiazolo(4,3-alpha)quinoxalin-1-one (ODQ) (30.0 micromol/l), a guanylyl cyclase inhibitor. However, 3-aminobenzamide (3.0 mmol/l), an inhibitor of poly(ADP- ribose)synthase, did not influence the relaxant effect of ONOO(-) (1.0 mmol/l). Results of the present study implicate that activation of K(+)(ATP) channels and/or cGMP/K(+)(ATP) channel interaction might play a role in the relaxant responses to ONOO(-) in isolated rat anococcygeus muscle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / pharmacology*
  • Glyburide / pharmacology
  • Guanylate Cyclase / antagonists & inhibitors
  • In Vitro Techniques
  • Male
  • Muscle Relaxation / drug effects
  • Muscle, Smooth / drug effects*
  • Muscle, Smooth / physiology
  • Oxadiazoles / pharmacology
  • Peroxynitrous Acid / pharmacology*
  • Potassium Channel Blockers / pharmacology
  • Quinoxalines / pharmacology
  • Rats

Substances

  • 1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one
  • Antioxidants
  • Oxadiazoles
  • Potassium Channel Blockers
  • Quinoxalines
  • Peroxynitrous Acid
  • Guanylate Cyclase
  • Glyburide