Rho激酶对严重烧伤大鼠血清诱导的肠黏膜上皮细胞调控机制的研究

目的:观察烧伤血清刺激下肠黏膜上皮细胞通透性的变化及Rho激酶信号转导通路所起的作用。方法:常规培养肠黏膜上皮CaCO-2细胞,分为正常对照组、烧伤血清组和烧伤血清6 h Y27632组,以FITC-albumin荧光强度检测法检测人肠黏膜上皮细胞在未烧伤、1、2、6、12、24 h时相点通透性变化指标;采用Western blot法检测人肠黏膜上皮细胞中肌球蛋白轻链(MLC)、磷酸化MLC(p-MLC)和Rho激酶蛋白水平在6个时相点的变化及烧伤血清6 h Y27632组总MLC、p-MLC及Rho激酶蛋白水平表达。结果:严重烧伤后人肠黏膜上皮细胞通透性明显增加,并呈时相依赖性变化,6~12 h达到最高;p-MLC以及Rho激酶蛋白表达均明显增加。上述蛋白表达的增强可在加入Rho激酶特异性抑制剂Y27632后取消。结论:烧伤大鼠血清能诱导肠黏膜上皮细胞内Rho激酶激活、p-MLC表达增加及肠黏膜通透性增加,抑制Rho激酶活性能逆转这一作用。

Mechanism of Rho kinase regulating serious burn serum-induced intestinal epithelial cells in rats

Objective:To observe the changes in the permeability of intestinal epithelial cells and the role of the Rho kinase signal transduction pathway under the burn serum stimulation.Methods:Conventionally cultured CaCo-2 cells were divided into a normal control,a burn and a 6 h Y27632 group.The intestinal permeability and the mucosal protein expressions were detected 1,2,6,12 and 24 hours after burn serum induction.Results:The permeability of intestinal epithelial cells was markedly enhanced in the induced serum in a time-dependent manner and reached the peak in 6-12 hours.The expressions of phosphorylated MLC(p-MLC) and Rho were obviously elevated,but the increasing effect was counteracted by the Rho kinase inhibitor Y27632.Conclusion:Burn rat serum can activate Rho kinase in the intestinal epithelial cells,elevate the expression of p-MLC and increase intestinal permeability,but the effect can be reversed by inhibiting the activity of Rho kinase.