Effects of glibenclamide and tolbutamide on ischemia- and ouabain-induced arrhythmias and membrane potentials of ventricular myocardium from rat and guinea pig.
Glibenclamide (Gli) 0.3, 1, 3 mg.kg-1 and tolbutamide (Tol) 3, 10, 30 mg.kg-1 iv 10 min before ischemia or ouabain infusion prevented ventricular fibrillation induced by ischemia in rat and arrhythmias induced by ouabain in guinea pig. Gli 10 mumol.L-1 and Tol 1 mmol.L-1 increased APD and ERP in rat ventricular muscle. Gli 0.1, 1, 10 mumol.L-1 and Tol 0.01, 0.1, 1 mmol.L-1 prevented and reversed the shortening of APD and ERP induced by hypoxia in guinea pig ventricular muscle. These effects of Gli and Tol were dose-dependent. The results confirmed that Gli and Tol were effective on arrhythmias induced by ischemia and ouabain by blocking ATP-sensitive potassium channel.
Zhang
H L
HL
Department of Pharmacology, Hebei Medical College, Shijiazhuang, China.
Li
Y S
YS
Fu
S X
SX
Yang
X P
XP
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000139:chemically induced / Q000517:prevention & control*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005905:Glyburide / Q000494:pharmacology / Q000627:therapeutic use*; D006168:Guinea Pigs; D000860:Hypoxia / Q000503:physiopathology; D007511:Ischemia / Q000150:complications; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D010042:Ouabain; D051381:Rats; D013045:Species Specificity; D014044:Tolbutamide / Q000494:pharmacology / Q000627:therapeutic use*; D014693:Ventricular Fibrillation / Q000209:etiology / Q000517:prevention & control*
D010042:Ouabain; D014044:Tolbutamide; D005905:Glyburide