【摘要】 目的研究马齿苋总黄酮（portulaca total flavone,PTF）对新生大鼠心肌细胞缺血再灌注损伤的保护作用。方法取体外培养的新生大鼠心肌细胞于缺氧24 h复氧1 h造成缺血再灌注（I/R）损伤模型,观察细胞损伤情况,并将PTF终浓度为5、10、20 mg/L分别加入培养基中,预处理24 h后,再置于上述缺氧复氧环境中培养,测定以上不同条件下心肌细胞上清液中的乳酸脱氢酶（LDH）、肌酸激酶（CK）、丙二醛（MDA）、超氧化物歧化酶（SOD）含量,并测定各组细胞内Ca²⁺浓度。结果与正常对照组相比较,缺血组和再灌组细胞上清液中LDH、CK、MDA含量明显升高（P<0.01）,SOD活力则显著降低（P<0.01）,缺血组和再灌组细胞内Ca²⁺浓度均明显升高（P<0.01）。而用PTF预处理后缺血组和再灌组的LDH、CK、MDA显著低于用药前（P<0.01）,SOD高于缺血组和再灌组（P<0.01）;PTF组（20mg/L）对正常心肌细胞内Ca²⁺浓度影响小（P>0.05）;与PDGF-BB诱导增殖组比较,PTF（5、10、20 mg/L）药物干预组心肌细胞Ca²⁺浓度明显降低（P<0.05）,且存在明显的剂量效应关系。结论 PTF对缺血再灌心肌细胞有保护作用,其作用机制可能与增强抗氧化能力、减轻钙超载有关。更多还原

【Abstract】 Objective To observe the protective effect of Portulaca Total Flavone（PTF） on cardiac myocyte injured by ischemia- reperfusion（I/R） in neonatal rats.Methods Cardiac myocytes from neonatal SD rat were cultured and pretreated with PTF in three different concentrations,5 mg/L,10 mg/L and 20 mg/L,before exposure to hypoxia for 24 h and reoxygenation for 1 h to create cell model of ischemia - reperfusion.Then lactate dehydrogenase （LDH）,creatine kinase（CK） release,methylenedioxyamphetamine（MDA） release,superoxide dismutase （SOD） activity were measured,and cell Ca²⁺[(Ca²⁺ )_i]was detected.Results Compared with the measurements taken in normal group,the LDH,CK and MDA in the supernatant of the cells in ischemia and reperfusion group increased highly（P <0.01）,SOD activity decreased sharply（P <0.01）,and Ca²⁺[(Ca²⁺ )_i]of cells in ischemia groups and reperfusion groups increased highly（P < 0.01）.Pretreatment of myocytes with PTF resulted in reduction in LDH,CK and MDA release（P <0.01） in I/R groups,Ca²⁺[(Ca²⁺ )_i]concentration of cells in PTF（20 mg/L）groups was nearer to normal group,when the myocytes were pretreated with PTF at 5,10, 20 mg/L,Ca²⁺[(Ca²⁺ )_i]concentration of cells decreased highly,Compared with the PDGF - BB induced breeding groups.There is marked dose - effect positive relationship in total flavone from portulaca.Conclusion There was the protective effect of PTF on cardiac myocyte injured by I/R in neonatal rats,its mechanism of action may apply to enhance ability of antioxidant and reduce the calcium overload.更多还原