Wang Shu-Feng, Li Guo-Wei
Department of General Surgery, First Hospital, Xi'an Jiaotong University, Xi'an 710061, Shannxi Province, China.
World J Gastroenterol. 2003 Aug;9(8):1866-70. doi: 10.3748/wjg.v9.i8.1866.
To investigate the early protective effect of ischemic preconditioning on small intestinal graft in rats.
SD rats were randomly divided into the following groups: sham operation group (S group, n=6), small bowel transplantation group (SBT group, n=12), ischemic preconditioning plus small bowel transplantation group (ISBT group, n=12). Heterotopic SBT was performed with a technique modified from that described by Monchik et al. When the graft was revascularized successfully and reperfused for 1 h, samples were obtained from the different groups. Laminin was analyzed with immunohistochemical staining. Quantitative analysis of laminin positive signals was performed using image acquiring analysis system. Apoptotic epithelia of small intestinal graft were detected by the TdT-mediated dUTP nick end labeling method. The morphological change of epithelial basement membrane was observed by transmission electron microscopy.
The mean optical density value of laminin positive signals was 39.52+/-2.60, 13.53+/-0.44, 25.40+/-1.79, respectively, in S, SBT and ISBT groups. The average optical density value of laminin positive products in SBT group was sharply lower than that in S group (P<0.05). However, the mean optical density value of laminin positive products in ISBT group was significantly higher than that in SBT group (P<0.05). The apoptotic index (AI) in S, SBT and ISBT group was 2.2+/-0.83,30.8+/-3.2, 13.2+/-2.86, respectively. The AI in SBT group was significantly higher than that in S group (P<0.05), and AI in ISBT group was sharply lower than that in SBT group (P<0.05). On transmission electron microscopy, the epithelial basement membrane in S group stayed normal, but in SBT group it became disrupted and collapsed, even disappeared. The lesion of epithelial basement membrane in ISBT group was slighter compared with that in SBT group.
Ischemic preconditioning has an early protective effect on epithelial cells and extracellur matrix of small intestinal graft. Inhibition of epithelial cell apoptosis may be one of the mechanisms of ischemic preconditioning.
探讨缺血预处理对大鼠小肠移植的早期保护作用。
将SD大鼠随机分为以下几组：假手术组（S组，n = 6）、小肠移植组（SBT组，n = 12）、缺血预处理加小肠移植组（ISBT组，n = 12）。采用对Monchik等人描述的技术进行改良后的方法行异位小肠移植。当移植物成功再灌注1小时后，从不同组获取样本。采用免疫组织化学染色分析层粘连蛋白。使用图像采集分析系统对层粘连蛋白阳性信号进行定量分析。采用TdT介导的dUTP缺口末端标记法检测小肠移植物的凋亡上皮细胞。通过透射电子显微镜观察上皮基底膜的形态变化。
S组、SBT组和ISBT组中层粘连蛋白阳性信号的平均光密度值分别为39.52±2.60、13.53±0.44、25.40±1.79。SBT组中层粘连蛋白阳性产物的平均光密度值明显低于S组（P<0.05）。然而，ISBT组中层粘连蛋白阳性产物的平均光密度值显著高于SBT组（P<0.05）。S组、SBT组和ISBT组的凋亡指数（AI）分别为2.2±0.83、30.8±3.2、13.2±2.86。SBT组的AI显著高于S组（P<0.05），ISBT组的AI明显低于SBT组（P<0.05）。透射电子显微镜观察显示，S组的上皮基底膜保持正常，但SBT组的上皮基底膜遭到破坏、塌陷，甚至消失。与SBT组相比，ISBT组上皮基底膜的损伤较轻。
缺血预处理对小肠移植物的上皮细胞和细胞外基质具有早期保护作用。抑制上皮细胞凋亡可能是缺血预处理的机制之一。
