断肢再植肌组织缺血再灌注损伤的细胞凋亡及Bax、Bcl-2表达

Study of the expression of Bax,Bcl-2 proteins and apoptosis in the ischemia-reperfusion muscular tissue of the isolated rat limb

目的研究断肢再植过程中缺血性损伤和缺血-再灌注损伤的发生情况和病理改变,探讨细胞凋亡及相关基因Bax、Bcl-2表达规律。方法建立大鼠后肢断肢实验模型,以光镜观察缺血和缺血再灌注早期的骨骼肌组织病理变化,检测缺血和缺血再灌注过程中细胞凋亡(apoptosis)现象的发生及相关基因表达。结果缺血5h的大鼠断肢再植全部存活,而缺血9h者未获存活。大鼠断肢再植过程中,缺血性和缺血-再灌注性损伤引起骨骼肌细胞水肿,坏死和细胞凋亡,并于再灌注过程观察到微循环障碍和中性粒细胞趋化浸润现象。缺血7h凋亡率最高,相关基因Bax表达与缺血时间成正比。Bcl-2表达与缺血时间成反比。结论骨骼肌存在缺血性和缺血-再灌注性损伤,细胞凋亡是缺血和缺血-再灌注损伤的重要病理改变。骨骼肌缺血再灌注过程存在微循环障碍和中性粒细胞趋化浸润,它们是缺血-再灌注损伤的重要原因之一。相关基因表达与凋亡的发生关系密切。

Objective To study the appearance of the ischemia injury and ischemia-reperfusion injury and the pathological alteration,and try to find out the law and action of the Expression of P53,P21, Bcl-2 proteins and Apoptosis during the isolated limb replantation. Methods Isolated hindlimbs of rats were used as experimental models, the pathological alteration of the ischemia and ischemia-reperfusion period was observed under the microscope, and the Expressionof Bax, Bcl-2 proteins and Apoptosis was detected during the ischemia and ischemia-reperfusion procedure. Results All of the rats isolated hindlimbs under 5 hours ischemia were replanted to be alive, but no one of under 9 hours ischemia was alive. During the procedure of the replantation of the rats＇ hindlimbs ischemia injury and ischemia-reperfusion injury could the muscular tissue to edema, necrosis and apoptosis. Microcirculation disorder and neutrophil tendency and infiltration were observed during the reperfusion process, apoptosis index is most high after ischemia 7h, the Expression of Bax proteins is direct ratio with ischemia time. The Expression of Bcl-2 proteins is inverse ratio with ischemia time. Conclusion There are icschemia injury and ischemia-reperfusion injury in the muscular tissue. Apoptosis is the important alteration of these injury. There were microcirculation disorder and neutmphil tendency and infiltration during the reperfusion process and they play an important role in the ischemia-reperfusion injury, the Expression of Bax, Bcl-2 proteins have a close relation with apoptosis.