缺血后适应对大鼠肾脏热缺血再灌注损伤凋亡相关基因bcl-2/bax表达的影响

目的探讨缺血后适应对大鼠肾脏热缺血再灌注损伤细胞凋亡相关基因bcl-2/bax表达的影响。方法将40只Wistar健康雄性大鼠随机分为对照组(C组)、缺血再灌注组(IR组)、缺血后适应组(IPo)和腺苷组(Ado组)4组。行右肾切除,左肾热缺血60min后再灌注24h建立大鼠肾脏急性热缺血再灌注损伤模型;C组仅右肾切除,左肾蒂游离;IPo组于再灌注前行6个10s无限制灌注加10s再缺血循环;Ado组于缺血前10min经静脉给予腺苷。采用逆转录聚合酶链反应技术(RT-PCR)和免疫组化法检测各组肾脏组织中细胞凋亡相关基因bcl-2/bax表达水平。结果与C组相比,缺血60min再灌注24h可以导致肾脏组织中bcl-2 mRNA、Bax mRNA表达的相对丰度显著升高(P<0.05)。与IR组比较,经过后适应(Pos-Con)或腺苷(Ado)干预后bcl-2 mRNA表达水平升高更加显著,BaxmRNA表达水平显著降低(P<0.05),两种处理之间无显著差异(P>0.05)。比较各组bcl-2/Bax的比值,IR组较对照组显著降低(P<0.05),而Pos-Con和Ado干预后,与IR组比较bcl-2/Bax的比值显著升高(P均<0.05),两种处理之间无显著差异(P>0.05)。结论缺血再灌注可以上调大鼠肾脏促凋亡基因bax的表达,下调凋亡抑制基因bcl-2的表达,进而可能导致肾脏细胞过度凋亡;缺血后适应能够抑制促凋亡基因bax的过度上调,同时促进凋亡抑制基因bcl-2的表达,进而可能防止肾脏细胞过度凋亡。

Effect of ischemic post-conditioning on bcl-2 and bax mRNA expression in rat kidney after acute hot ischemic-reperfusion

Objective To explore the influence of ischemic post-conditioning(IPo) on the Bcl-2 and Bax mRNA expression in the kidney of rats,suffering from acute renal ischemic-reperfusion injury(IRI).Methods After right side nephrectomy,an acute IRI model was established through 60min of warm ischemia and 24h of reperfusion without control on the left kidney.Forty Wistar rats were divided into 4 groups randomly: group Ⅰ(Control),group Ⅱ(I/R),group Ⅲ(IPo),and group Ⅳ(Ado).After 24h reperfusion without control,renal samples were taken.The mRNA expression of Bcl-2 and Bax in the samples was examined by RT-PCR and immunohistochemitry.Results Compared with the control group,the mRNA expression of Bcl-2 and Bax of the I/R group were unregulated remarkably(P<0.05).After the intervention of IPo or Ado,the upregulations of Bcl-2 mRNA expression were more notable than that of I/R group,while the Bax mRNA expression were lower than that of I/R group(P<0.05).But there was no significant difference between the levels of Bcl-2 and Bax mRNA expression in IPo group and Ado group.Conclusion The application of IPo may suppress the excessive apoptosis of kidney cells by suppressing the upregulation of Bax mRNA expression,and enhancing the Bcl-2 mRNA expression.