A study of the time-dependent changes in myocardial ischemia/reperfusion injury / 中国病理生理杂志

ABSTRACT

The time-dependent changes in myocardio membrane system during ischemia/reperfusion injury were studied with ligature of the left ventricular branch of coronary artery in rabbit. The permeability of cardiac membrane system being tested by using lanthanum tracer technique and stereological methods. Lanthanum granules were observed in the sarplacosma and sarccpiasmic tubes especially at ischemia for 20min. The pecmeability of membrane system for La~(+++) was more marked when hearts were reperfused for 20min. With the increase in time of ischemia, the changes became more and more serious. A lot of lanthanum granules were entered into mitochondria when the hearts were reperfused after 40min ischemia. There were neither intact mitichondria nor lanthanum granules in mitochondria observed when the hearts were reperfused after 60min ischemia. The structural changes were irreversible at this stage of reperfusion The results of our study indicated that the changes of permeability of cardiac cell for La~(+++) in ischcmia/reperfusion are time-dependent, 40min ischemia is the demarcation line between the reversible and irreversible injury during reperfusion. On the basis of our experiment, we like to propose a new conception of reversible and irreversible injury of reperfusion.