前胡丙素对缺血/再灌注过程中心肌细胞膜钙调节蛋白的影响  

Effects of praeruptorin C on myocardial plasma membrane calcium handling proteins during ischemia/reperfusion

作　　者：奚群英[1] 祝宝华[1] 刘晨[1] 张能锋[1] 

机构地区：[1]东南大学医学院附属扬州医院心内科,江苏扬州225001

出　　处：《心脏杂志》2008年第5期513-516,共4页Chinese Heart Journal

基　　金：江苏省135工程医学重点人才基金项目资助(RC2002016)

摘　　要：目的探讨中药单体前胡丙素(Pra-C)对缺血/再灌注(I/R)心肌细胞保护作用的机制。方法将培养的乳鼠心肌细胞随机分为I/R组、Pra-C预处理组和对照组。用全自动生化仪测定各组乳酸脱氢酶(LDH)的漏出量(n=5)。半定量RT-PCR检测钠钙交换蛋白(NCX)mRNA的转录(n=3),其活性以液闪仪测定Na+依赖的45Ca2+摄取率表示(n=5)。细胞膜钙ATP酶(PMCA)的活性以定磷比色法测定(n=5)。结果I/R组LDH的漏出量显著增加(P<0.01),Pra-C预处理组与I/R组比较LDH的漏出量显著降低(P<0.01)。I/R组NCX Na+依赖的45Ca2+摄取率比对照组显著增高(P<0.01),Pra-C预处理组较I/R时45Ca2+摄取率降低(P<0.01)。I/R组NCXmRNA的水平比对照组显著高(P<0.01);Pra-C预处理组较I/R组NCX mRNA的水平显著低(P<0.01)。各组间PMCA的活性无显著性差异。结论Pra-C可显著减轻I/R损伤;其对I/R心肌的保护与下调细胞膜NCX mRNA的转录和其蛋白的活性有关。AIM To explore the cardioprotective mechanism of praeruptorin C （Pra-C） during ischemia/ reperfusion. METHODS Cultured rat neonatal cardiomyocytes were randomly divided into 3 groups： ischemia/reperfusion group （9 h isehemia followed by 1 h reperfusion, I/R ）, Pra-C pretreatment group （pretreated with Pra-C for 1 h before I/R） and control group. The leakage of intracellular lactate dehydrogenase （LDH） in various groups was determined by biochemical autoanalyzer. Activity of natrium-calcium exchanger（NCX） was indicated by Na^＋-dependent ^45Ca^2＋ uptake tested by liquid scintillation counting. Semi-quantitative RT-PCR was employed to detect the mRNA level of NCX. Activity of plasma membrane calcium ATPase （PMCA） was determined by microcolorimetrg of inorganic phosphorus. RESULTS Compared with that in I/R group, the LDH leakage in Pra-C pretreatment group was significantly reduced （P 〈 0. 01 ）. The Na^＋ -dependent ^45Ca^2＋ uptake was significantly increased in I/R group （P 〈 0. 01 ） compared with that in control group. This increase could be significantly attenuated in Pra-C pretreatment group. The level of NCX mRNA in I/R group was also significantly increased （P 〈 0. 01 ） compared with that in control group and this increase could be significantly attenuated in Pra-C pretreatment group （P 〈 0. 01 ）. No significant change of PMCA activity was observed between various groups. CONCLUSION NCX mediates the cardioprotective effect of Pra-C during isehemia/reperfusion in the neonatal rat cardiomyocytes I/R model.

关 键 词：前胡丙素 缺血/再灌注损伤 心肌 钠钙交换蛋白 

分 类 号：R542.2[医药卫生—心血管疾病]