Effect of Mg~(2+) on cardiac function of isolated perfused rat heart with endothelin / 中国病理生理杂志

ABSTRACT

This work observed on isolated perfused rat hearts, that 10~(-9)mol/L endothelin (ET) induced myocardial contracture, decrease of heart function and coronary flow, intramyocardial Ca~(2+) accumulation and Mg~(2+) loss and etc. These cardiac action of ET were obviously more prominent when Mg~(2+) in the perfusion fluid was lowered to 0.12 mmol/L, and were significantly alIeviated when Mg~(2+) content was increased to 4.8mmol/L (normal plasma Mg~(2+) content is about 1.2 mmol/L). The mechanism of the Mg~(2+) effect on the cardiac action of ET may be related to its inhibition of Ca~(2+) influx into the myocytes. These results suggested that without magnesium defficiency, suitable replenishment of Mg~(2+) probably have practical clinical significance in the prevention and therapy of myocardial injury occurred during diseases with elevated circulatory ET level.