EFFECTS OF DAURlCINE ON THE ELECTROPHYSIOLOGICAL CHARACTERISTICS AND ARRHYTHMIA INDUCED BY ACUTE CORONARY ARTERY LIGATION AND REPERFUSION IN ANESTHETIZED CATS / 中国药理学通报

ABSTRACT

Dauricine ( Dau ) significantly prolonged monophasic action potential duration of 50% and 90% repolarization ( MAPD50 and MAPD90 ) and functional refractory period (FRP)of the hearts in anesthetized cats in dose-dependent manner. At 9 mg/kg of Dau, MAPD50 was increased from 170?19 ms to 197?20 ms; MAPD90 from 216?16 ms to 249?18 ms; FRP from 177 ? 15 ms to 238 ? 20 ms.Dau 5 mg/kg iv followed by constant perfusion for 30 min could prevent the shortening of MAPD50 in the ischemic boundary area ( BA ) and increased FRP in the non-ischemic area ( NA ) , ischemic central area ( CA ) and BA, and markedly reduced the extent of dispersion of FRP of hearts in anesthetized cats. The results suggest that the antagonizing effect of Dau on the arrhythmias caused by acute myocardial ischemia and reperfusion might be related to its action of prolonging FRP and decreasing the dispersion of FRP in ischemic hearts.