急进高原大鼠肠黏膜机械屏障损伤后细胞自噬变化的初步研究

目的探讨急进高原大鼠肠黏膜机械屏障损伤后细胞自噬的变化情况。方法50只Wistar大鼠随机分为5组：平原组，急进高原6h组、12h组、24h组、48h组，每组各10只。通过低压低氧动物实验舱模拟急进海拔4767m建立急进高原大鼠模型。观察各组大鼠肠黏膜机械屏障损伤情况，用透射电镜观察肠上皮细胞中自噬体；用免疫组织化学法检测肠上皮细胞中自噬相关蛋白Beclinl及LC3B表达。结果与平原组比较，急进高原组可使其肠黏膜机械屏障发生损伤，并且在急进高原肠黏膜损伤6h后可观测到自噬体，24h后检测到自噬相关蛋白Beclinl及LC3B表达显著增高（P〈0．01）。结论急进高原组大鼠肠黏膜机械屏障损伤后自噬相关蛋白Beclinl及LC3B表达明显增加，表明急进高原大鼠肠黏膜机械屏障损伤后细胞自噬活性上调。

Preliminary study on autophagy after the failure of intestinal mucosal mechanical barrier in model rats acutely exposed to high altitude

Objective To investigate the change of the autophagy after the failure of intestinal mucosal mechanical barrier in model rats acutely exposed to high altitude. Methods Fifty Wistar rats were randomly divided into five groups ： the plain group, the acute high altitude 6 h, 12 h ,24 h and 48 h group, each consisting of 10 rats. The a- cute high altitude groups were established at radical altitudes of 4 767 meters by decompression chamber. The dam- age of the intestinal mucosal mechanical barrier were observed. The autophagosome in the intestinal epithelial cells was observed by transmission electron microscopy. The expression of the Beclinl and LC3B in the intestinal epithe- lial cells was analyzed by immunohistochemistry. Results Compared with the plain group, acutely exposed to high altitude may damage the intestinal mucosal mechanical barrier, and the autophagosome was observed after the fail- ure of intestine in the acute high altitude 6 h. The expression of the Beclinl and LC3B in acute high altitude 24 h was significantly higher （P 〈 0.01 ）. Conclusion The failure of intestinal mucosal mechanical barrier may in- crease the Beclinl and LC3B in model rats acutely exposed to high altitude which indicated that the up-regulation of the autophagic activity.