The mechanisms of peroxynitrite-induced relaxations in isolated rat anococcygeus muscle.
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.
Ademoğlu
Feyza
F
Department of Pharmacology, Faculty of Pharmacy, Gazi University, Ankara, Turkey. feyzade@yahoo.com
Başgut
Bilgen
B
Abacioğlu
Nurettin
N
Cakici
Iclal
I
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D005905:Glyburide / Q000494:pharmacology; D006162:Guanylate Cyclase / Q000037:antagonists & inhibitors; D066298:In Vitro Techniques; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D010069:Oxadiazoles / Q000494:pharmacology; D030421:Peroxynitrous Acid / Q000494:pharmacology*; D026902:Potassium Channel Blockers / Q000494:pharmacology; D011810:Quinoxalines / Q000494:pharmacology; D051381:Rats
C095284:1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one; D000975:Antioxidants; D010069:Oxadiazoles; D026902:Potassium Channel Blockers; D011810:Quinoxalines; D030421:Peroxynitrous Acid; D006162:Guanylate Cyclase; D005905:Glyburide