Effect And Calcium Mechanism Of Salvianolic Acid A On Myocardial Ischemia Reperfusion Injury

Effect and calcium mechanism of Salvianolic Acid A on myocardial ischemia reperfusion injurySalviae Miltiorrhizae Radix (known as Danshen in Chinese) is a very commonly used herbal medicine for its significant clinical effects on cardiovascular disease, gynecological disease, beriberoid disease, wound, etc. in China. Salvianolic Acid A (SAA){(2R)-3-(3,4-Dihydroxyphenyl)-2-[(E)-3-[2-[(E)-2-(3,4-dihydroxyphenyl)ethen yl]-3,4dihydroxyphenyl]prop-2-enoyl]oxypropanoic acid} is the main effective, water-soluble constituent of salvia miltiorrhiza. Recently, our laboratory has found that SAA has significant anti-anoxia effect on cardiomyocytes, and this may provide experimental evidence to attenuate myocardial ischemia reperfusion injury. At first, we observed its protection effect on mitochondrion in the model of cultured cardiocytes subjected to hypoxia and reoxygenation through MTT test. To our current knowledge, little is known about the effect of SAA on calcium channels in ventricular myocytes, though calcium overload plays a very important part in myocardial ischemia reperfusion injury.Our present study was to examine the effects of SAA on L-type calcium channels in isolated rat ventricular myocytes and further to explore the possible mechanism of SAA for the management of ischemic heart diseases, at the same time we also tested its effect on intracellular calcium concentration in isolated single ventricular myocytes.Part one:The effect of SAA on the activity of myocytes subjected to hypoxia and reoxygenationObjective:to obsere effect of SAA on the activity of myocytes subjected to hypoxia and reoxygenationMethod:test the OD values through SynergyTM4 systemResults:the OD values were (0.439±0.007),(0.395±0.008),(0.367±0.019) respectively in the three SAA groups and there were significant differences compared with the model group (P＜0.01). Conclusion:SAA can obtain the activity of myocytes subjected to hypoxia and reoxygenation in a does-dependent manner.Part two:Blocking effect of Salvianolic Acid A on calcium channels in isolated rat ventricular myocytesObjective:to study the effect of saa on L-type calcium channels in isolated ventricular myocytes in sd rat.Method:the traditional whole-cell patch-clamp recording technique.Results:SAA (1,10,100, 1000μmol/L) inhibited I-CaL peak value by (16.23±1.3) %(n=6,p<0.05), (22.9±3.6)%(n=6,p<0.05), (53.4±3.0)%(n=8,p<0.01), (62.26±2.9)%(n=6,p<0.01) respectively. SAA reversibly inhibited I-CaL in a does-dependent manner, and with a half-blocking concentration IC50 of 38.3μmol/L. 10,100μmol/L SAA elevated theⅠ-Ⅴcurve obviously, shifted the half-active voltage to more positive(n=6, P＜0.05). However, it did not alter the shapes ofⅠ-Ⅴcurve, steady-state inactivation curve or recovery from inactivation curve.Conclusion:SAA inhibited I-CaL in a does-dependent manner.Part three:Effect of SAA on intracellular calcium concentration in ventricular myocytes.Objective:to observe the effect of SAA on intracellular calcium concentration in ventricular myocytes.Method:laser scanning microscope techniqueResults:at resting level, SAA50μmol/L did not affect the intracellular calcium concentration(P>0.05). However, it obviously inhibited the increase of calcium concentration induced by KCl compared with control(P<0.05).Conclusion:SAA can inhibited the increase of intracellular calcium concentration induced by KCl.