缺血后适应对大鼠乳鼠心肌细胞缺血再灌注损伤的保护作用

目的探讨缺血后适应对大鼠乳鼠心肌细胞缺血/再灌注损伤的保护作用。方法Wist-ar乳鼠（出生后3～7d）心肌细胞培养3～5d,随机分为四组：正常对照组（N组）,缺血/再灌注组（I/R组）,缺血后适应组（PC组）,PKCε抑制剂组（PKCI组）。采用pH6.8的D-Hands液饱和氮气和含20%新生牛血清的DMEM液复制心肌缺血/再灌注模型。检测各组MTT检测细胞存活率、乳酸脱氢酶（LDH）活力和丙二醛（MDA）含量变化,TUNEL染色观察细胞凋亡,Western blot检测PKCε蛋白表达水平。结果I/R组和PKCI组的MTT比色法检测的细胞存活率低于对照组和PC组,而LDH活力和MDA含量高于对照组和PC组。TUNEL染色细胞凋亡结果显示I/R组细胞凋亡显著,凋亡细胞核呈棕褐色,而PC组细胞存活状态良好,心肌细胞核多染成蓝色。同时,PKCI组的PKCε的蛋白表达水平低于PC组。结论缺血后适应对大鼠乳鼠心肌细胞缺血/再灌注损伤具有保护作用,且PKCε的激活参与其中。

The peotection of postconditioning for cardiomyocytes of neonatal rats in Ischemic-reperfusion injure

Objective To observe the protection of postconditioning for cardiomyocytes of neonatal rat in Ischemic/reperfusion injure. Methods The ventricular cardiomyocytes of Wistar neonatal rats （ 3-7 days after birth ） were incubated for about 3-5 days ,then randomly divided them into 4 groups：（1） Sham control group （2） Ischemic/ reperfusion group （3） postconditioning group （4） PC ＋ PKCε inhibitor group.We incubated neonatal cells in the D-hanks solution （pH=6.8） which was saturated with N2 gas and then re-incubated in the DMEM solution which contained 20% new-born calf serum to establish a model of I/R.To detect the viability of cardiomyocytes was assayed by MTT,the activity of LDH and the content of MDA were determined,apoptotic cells were measured by TUNEL assay,and the expression PKCε of each group was analyzed by Western Blot. Results The viability of cardiomyocytes assayed by MTT in I/R and PKCI groups was lower than that in N and PC groups;while the activity of LDH and the content of MDA were significantly higher than those in N and PC groups,so was the apoptosis index of TUNEL.The quantitative expression of PKCε in PKCI group was lower than that in PC group. Conclusions Postconditioning plays protection role for cardiomyocyte of neonatal rat in Ischemic/ reperfusion injure,the activating of PKCε involved.