EFFECTS OF FUROSEMIDE ON ACTION POTENTIAL AND CONTRACTILE FORCE OF ISOLATED TOAD ATRlAL MYOCARDIUM / 中国药理学通报

ABSTRACT

Using floating microelectrode, the effects of furosemide on action potential and contractile force were studied in isolated toad atrial myocardium. Furosemide increased the force of contraction of toad right atrial myocardium, amplitude and dV/dtmax of action potential, and prolonged action potential duration at 50% repolari-zation (APD50), but the APD25, APD90 and sinus cycle length ( SCL) were not influenced. The positive intropic effect of furosemide could be blocked by Verapamil. These results indicated that furosemide could promote the Ca++ inward current.