核因子-κB对感染性休克小鼠心肌细胞凋亡的影响

Influence of Nuclear Factor-κB on Cardiac Myocyte Apoptosis in Septic Shock Mouse

目的探讨核因子-κB(NF-κB)对感染性休克小鼠心肌细胞凋亡的影响,了解感染性休克时心功能减退的机制。方法随机将20只Wistar小鼠分为感染性休克组和对照组。感染性休克组(n=10)小鼠麻醉后固定,沿腹正中线作1.5 cm切口,结扎盲肠根部,用14号针头穿刺盲肠4次,之后将盲肠还纳腹腔,逐层缝合腹壁切口,于12 h后断头取血,分离血清,并留取其心脏组织标本。对照组小鼠(n=10)除不进行盲肠结扎穿孔外,其余操作均同感染性休克组。均采用免疫组织化学法测定二组心肌组织NF-κB蛋白表达及心肌细胞凋亡情况。结果感染性休克组心肌细胞内NF-κB抗原表达明显上调,其中强阳性9例,中等阳性1例;对照组呈阴性8例,弱阳性2例,二组阳性率比较差异有统计学意义(P<0.05)。感染性休克组心肌细胞凋亡指数(5.33±0.49)明显增加,与对照组心肌细胞凋亡指数(0.65±0.08)比较差异有统计学意义(P<0.05)。结论小鼠感染性休克过程中,NF-κB蛋白表达升高,心肌细胞凋亡增加,可能是感染性休克时NF-κB通过心肌细胞凋亡信号转导的作用,导致心肌细胞凋亡增加,以致心功能减退。

Objective To explore the effect of nuclear factor - kappaB （ NF - κB） on cardiac myocyte apoptosis and understand the molecular mechanism of decrease of heart function in septic shock rats. Methods Twenty Wistar rats were randomly divided into the septic shock group and the normal control group. The septic shock group（ n = 10） were fixed with anaesthesia and made into 1.5 cm slices just along the abdomen midline. Then the roots of appendices were returned to the belly cavity after being ligated and punctured 4 times with the No. 14 pinhead. After that,the slices were sewn up layer by layer. After 12 hours,the rats were all sacrificed, the blood taken and the serum separated. In the end, the heart specimens of the septic shock group were set aside. Meanwhile, the normal control group were dealt with in the same way except that they were not subjected to cecal ligation and puncture. Then NF - κB protein levels in cardiac tissue and the index of cardiac myocyte apoptosis were measured. Results NF - κB protein levels in the septic shock group （9 cases were strong masculine gender, 1 case was middle masculine gender）elevated significantly compared with the normal control group（8 cases were negative gender,2 cases were weak masculine gender） in cardiac tissue（ P 〈 0. 05 ）. Meanwhile, the index of cardiac myocyte apoptosis（5.33 ± 0. 49 ） increased markedly compared with normal control group （0.65 ± 0.08 ） （ P 〈 0.05 ）. Conclusions NF - κB protein levels elevate during septic shock, while the index of cardiac myocyte apoptosis increased. This may lead to the increase of myocyte apoptosis and the decrease of heart function through the role of NF - κB on signal transduction of cardiac myocyte apoptosis during the septic shock.