Effects of GBE50 on physiological characteristics and intracellular free calcium of myocardium / 中国中药杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate effects of GBE50 on the physiological characteristics and intracellular free calcium of myocardium.</p><p><b>METHOD</b>The preparations of isolated atria of guinea pigs were used for recording the myocardial physiological characteristics and the technique of Fluo-3/AM was used for measuring the concentration of free calcium in myocytes.</p><p><b>RESULT</b>GBE50 (10, 20, 40, 80, 160 mg x L(-1)) prominently inhibited the contractive force and decreased spontaneous beat of right atrium in concentration-dependent manner. GBE50 (10, 20, 40, 80, 160 mg x L(-1)) inhibited the contractive force of left atrium, and markedly decreased the post rest potentiation of myocardial contractility in left atrium in concentration-dependent manner. GBE50 (10, 20, 40, 80, 160 mg x L(-1)) prolonged the function refractory period of isolated guinea pig left atrium. 50 mg x L(-1) GBE50 decreased [Ca2+]i of guinea pig ventricular myocytes in normal Tyrode's solution by (46.53 +/- 8.44)% in 12 minutes.</p><p><b>CONCLUSION</b>GBE50 induces inhibitory effects of the spontaneous beat, contractility, post-rest potentiation and prolonged the function refractory period. GBE50 may decrease [Ca2+]i of guinea pig ventricular myocytes.</p>