大鼠在体心肌缺血再灌注损伤组织间液钙离子动态与胞膜L型电压依赖性钙通道表达  

Interstitial calcium and sarcolemal LVDCC expressing in rat myocardial ischemia reperfusion injury in vivo

作　　者：黄邵洪[1] 荣健[2] 刘子由[2] 刘海[2] 吴钟凯[2] 

机构地区：[1]中山大学附属第三医院胸心外科,广州510630 [2]中山大学附属第一医院心脏外科

出　　处：《中华临床医师杂志（电子版）》2011年第22期6538-6543,共6页Chinese Journal of Clinicians(Electronic Edition)

基　　金：国家杰出青年科学基金(30525020);教育部博士点基金(20050558050);人事部留学人员项目(粤人发2006-11);广东省科技厅国际合作项目(2007B050200024)

摘　　要：目的检测大鼠心肌在体缺血再灌注损伤(IR)组织间液钙离子浓度,比较IR前后心肌胞膜L型电压依赖性钙通道(LVDCC)mRNA表达水平,探讨其对钙超载的意义。方法 12只SD大鼠随机分为IR组和对照组,以微透析技术连续收集心肌组织间液标本,原子吸收光谱法检测钙离子浓度。IR组通过结扎(20min)后松解(60min)前降支造成心肌缺血再灌注,结束时收取左心室缺血区和右心室心肌行LVDCCmRNA定量PCR检测,实验前后采血检测血钙和肌钙蛋白T(cTnT)。对照组免除结扎松解前降支,其余操作与IR组一致。结果 IR组血浆cTnT浓度显著升高[对照组vs.IR组:(1.62±0.60)ng/mlvs.(4.29±2.22)ng/ml,P=0.031]。IR组心肌组织间液钙离子浓度在缺血期无变化,再灌注20min显著下降,心肌析出液钙离子浓度与对照组存在显著性差异[对照组vs.IR组:(224.25±31.75)μmol/Lvs.(136.25±39.50)μmol/L,P=0.031]。血浆钙离子浓度实验前后无显著差异。心肌细胞膜LVDCCmRNA表达水平在组间和组内均无显著差异。结论大鼠在体心肌缺血20min再灌注60min,组织间液钙离子浓度在缺血期无明显变化,再灌注期迅速下降,这种变化趋势与胞膜LVDCC表达无关。Objective To detect the dynamics of interstitial calcium and sarcolemal LVDCC mRNA expressing in rat myocardial ischemia reperfusion injury(IR)in vivo.MethodsTwelve SD rats were randomized into IR or control groups.Myocardial interstitial fluid was collected continously with microdialysis technique and calcium concentration was measured with an atomic absorption spectrophotometer.In IR group,LAD was ligated for 20 mins then released for 60 mins to achieved IR effects.The left ventricle(ischemic area)and right ventricle was harvested for quantitative PCR of sarcolemal LVDCC at the end.Serum calcium and cTnT were also detected before and after IR.Procedures were the same in control group but no ligating/releasing LAD.ResultsThe cTnT was elevated significantly in IR group[control vs.IR:(1.62±0.60)ng/ml vs.(4.29±2.22)ng/ml,P=0.031].Interstitial calcium concentration kept steady during ischemia,while went down sharply at 20 minutes later in reperfusion.Dialysate calcium concentration of IR group was significantly lower than that of control[control vs.IR:(224.25±31.75)μmol/L vs.(136.25±39.50)μmol/L,P=0.031].There was no difference in both groups for serum calcium before and after experiment.There were no differences in and between groups for sarcolemal LVDCC mRNA expressing.ConclusionsIn this 20 minutes myocardial ischemia and 60 minutes reperfusion injury rat model in vivo,interstitial calcium concentration keeps steady during ischemia,while goes down sharply after reperfusion,which does not correlate with sarcolemal LVDCC mRNA expressing.

关 键 词：再灌注损伤 钙通道 L型 大鼠 

分 类 号：R542.2[医药卫生—心血管疾病]