烧伤后肠黏膜细胞外基质与细胞凋亡关系的实验研究

An experimental study on the relationship between the extracellular matrix and apoptosis of intestinal epithelium after burn injury

目的 探讨烧伤后大鼠肠黏膜细胞凋亡与细胞外基质的关系。 方法 30只Wistar大鼠随机分为烧伤后 6、12h,1、3、5d组及正常对照组 ,每组 5只。检测肠黏膜上皮细胞凋亡数、cas pases 3酶活性、细胞外基质成分 (层粘连蛋白、Ⅳ型胶原 )含量 ,并作相关分析。 结果 烧伤后大鼠肠上皮凋亡细胞数、caspases 3的活性较正常对照组明显升高 (P <0.0 5或 0 .0 1) ,大鼠肠黏膜层粘连蛋白、Ⅳ型胶原含量较正常对照组下降 ( P <0.0 5或 0 .0 1)。直线相关分析结果 :烧伤后肠黏膜层粘连蛋白、Ⅳ型胶原含量变化与细胞凋亡数呈显著的负相关 (r =- 0.5 75, - 0.6 13,P <0 0 5 )。 结论 烧伤后大鼠肠黏膜细胞凋亡增加 ,且与细胞外基质的变化相关。

Objective To explore the relationship between the extracellular matrix and apoptosis of intestinal epithelium after burn injury. Methods Thirty Wistar rats were employed in the study and were randomly divided into normal control (C) and 6PBH (postburn hour), 12PBH, 1PBD(postburn day), 3PBD and 5PBD groups with 5 rats in each group. The rats in burn groups were sacrificed at 0, 6 and 12 PBHs and 1, 3 and 5 PBDs. The apoptotic cell count and the caspases 3 activity of intestinal mucosal epithelium, and the extracellular matrix component laminin and type Ⅳ collagen were determined and their correlation was analyzed. Results The apoptotic cell count and the caspases 3 activity of intestinal mucosal epithelium in burn groups were obviously higher than those in C group (P<0.05 or 0.01), while the intestinal mucosal contents of laminin and type Ⅳ collagen in burned groups were much lower than those in C group (P<0.05 or 0.01). By linear correlative analysis, it was shown that the changes in the intestinal mucosal contents of laminin and type Ⅳ collagen in burned groups were negatively correlated with the change in apoptotic cell count (r=-0.575, -0.613, P<0.05). Conclusion Intestinal epithelial apoptosis was enhanced after burn injury, and it was correlated with the change in the components of the extracellular matrix.