甘氨酸拮抗内毒素性离体心脏损伤的作用研究

目的研究甘氨酸拮抗内毒素性离体心脏心损伤的作用。方法取健康体重(250～30)gSD♂大鼠21只随机分成3组,正常对照组(n=7),内毒素组(n=7),甘氨酸+内毒素组(n=7),在Langendorff装置上用KrebsHenseleit(KH)液对大鼠离体心脏行主动脉逆灌。连续记录心肌细胞单相动作电位(MAP),在相应的时点分别测定冠脉流出液中的乳酸脱氢酶(LDH)、肌酸激酶(CK)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。结果甘氨酸组对内毒素损伤引起的心肌细胞单相动作电位幅度减小及D20延长有改善作用,减少内毒素损伤引起的LDH和CK的释放,同时可以逆转内毒素诱导的心肌SOD活性降低和MDA含量升高。结论甘氨酸可以拮抗内毒素性心肌损伤,与其改善心肌功能状态和减少自由基的生成有关。

Effect of Glycine on endotoxin induce myocardial cell injury of isolated rat heart

Aim To observe the protective effect of glycine from myocardial cell injury of the isolated rat heart induced by endotoxin. Methods 21 male SD rats,weghting(250±30)g,were randomly divided into three groups:control group(n=7),endotoxin group(n=7),glycine/endotoxin group(n=7).Heart were isolated from the rats and perfused on Langendorff apparatus with Krebs-Henseleit(KH)buffer(Saturation 95%+5% CO_2)at a constant pressure(8.33 kPa)and temperture(37℃). The activities of lactate dehydrogenase(LDH),creatine kinase(CK),superoxide dismutase(SOD) and the level of malondialdehyde (MDA) of efflux from coronary artery, monophasic action potential(MAP)were determined at the certain time(0,20,50,80 min). Results Monophasic action potential were markedly improved in Gly/ET group. Glycine can attenuate the release of LDH,CK from myocardial cell. The activity of SOD and the level of MDA were close to control group. Conclusion Glycine can protect myocardial cells of the isolated rat heart from the damage induced by endotoxin.