Department of Pediatric Surgery, Dana-Dwek Children's Hospital, Tel Aviv Sourasky Medical Center, 6 Weizmann st, 6423906, Tel Aviv, Israel.
Department of Physiology, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
Pediatr Surg Int. 2021 Mar;37(3):369-376. doi: 10.1007/s00383-020-04817-7. Epub 2021 Feb 10.
We investigate the mechanism of intestinal cell apoptosis and its relation to the time of reperfusion in a rat model of intestinal ischemia-reperfusion (IR).
Rats were divided into 4 groups: Sham-24 and Sham-48 rats underwent laparotomy without an intentional ischemic intervention and were sacrificed 24 or 48 h hours later; IR-24 and IR-48 rats underwent occlusion of SMA and portal vein for 20 min followed by 24 or 48 h of reperfusion, respectively. Park's injury score, cell proliferation and apoptosis were determined at sacrifice. Proliferation and apoptosis-related gene and protein expression were determined using Real-Time PCR, Western Blot and Immunohistochemistry.
IR-24 rats demonstrated a strong increase in cell apoptosis along with an elevated Bax and decreased Bcl-2 expression and a decrease in cell proliferation (vs Sham-24). IR-48 group showed an increase in cell proliferation and a decrease in cell apoptosis compared to IR-24 animals. IR-48 rats demonstrated an increase in apoptotic rate that was accompanied by greater TNF-α mRNA, Fas mRNA and FasL mRNA compared to Sham-48 animals.
While cell apoptosis in IR-24 rats is regulated mainly by intrinsic apoptotic pathway, 48 h followed ischemia extrinsic apoptotic pathway is responsible for pro-apoptotic effects of IR injury.
我们研究了肠细胞凋亡的机制及其与肠缺血再灌注（IR）再灌注时间的关系。
将大鼠分为 4 组：假手术 24 小时和假手术 48 小时组大鼠行剖腹术而不进行故意缺血干预，然后分别在 24 或 48 小时后处死；IR-24 和 IR-48 组大鼠夹闭 SMA 和门静脉 20 分钟，然后分别再灌注 24 或 48 小时。在处死时测定 Park 损伤评分、细胞增殖和凋亡。使用实时 PCR、Western Blot 和免疫组化测定增殖和凋亡相关基因和蛋白表达。
IR-24 大鼠细胞凋亡明显增加，Bax 表达升高，Bcl-2 表达降低，细胞增殖减少（与 Sham-24 相比）。IR-48 组与 IR-24 动物相比，细胞增殖增加，细胞凋亡减少。与 Sham-48 动物相比，IR-48 大鼠的凋亡率增加，伴随 TNF-αmRNA、Fas mRNA 和 FasL mRNA 增加。
IR-24 大鼠的细胞凋亡主要由内在凋亡途径调节，而缺血后 48 小时外源性凋亡途径负责 IR 损伤的促凋亡作用。
