应激性溃疡大鼠血浆EGF水平和胃上皮细胞凋亡的变化

目的　探讨应激性溃疡大鼠胃黏膜上皮细胞凋亡以及血浆表皮生长因子 (epidermalgrowthfactor,EGF)的变化。方法　制作大鼠水浸束缚应激 (water immersionandrestraintstress,WRS)模型。采用原位末端标记(TUNEL)法、电镜和荧光染色共聚焦显微镜方法分别检测胃黏膜上皮细胞的凋亡 ;放免法检测不同时段WRS大鼠血浆EGF的含量。结果　实验组与对照组相比 :血浆EGF含量明显下降 (P <0 .0 5 ) ,胃黏膜上皮细胞凋亡明显增加 (P <0 .0 5 ) ,溃疡指数 (UI)明显增加 (P <0 .0 1) ,且与应激时间呈正相关 (r =0 .975 0 ,P <0 .0 1)。结论　应激促使大鼠胃上皮细胞凋亡 ,凋亡参与了胃黏膜的损害过程 ;应激引起血浆EGF含量的下降 ;胃黏膜的损害可能与失去内源性EGF对胃黏膜的保护作用有关。

Changes of Plasma EGF and Apoptosis of Gastric Epithelium Mucosae in Experimental Stress-induced Ulcers in Rats

Objective To investigate the change of plasma EGF and apoptosis of gastric epithelium mucosae in experimental stress-induced ulcers in rats. Methods Forty rats were exposed to water-immersion restraint stress (WRS).The appoptotic cells in the gastric mucosa were examined through the methods of terminal deoxynucleatidyl transferase mediated DUTP nick and labeling(TUNEL),electron microscope and confocal microscopy;plasma EGF of different time points in experimental stress-induced ulcers in rats were detected by radioimmunoassay. Results Experimental group compared with those in the control group,the concentration of plasma EGF significantly decreased(P<0.05),apoptosis of gastric epithelium mucosae significantly increased(P<0.05),ulcer index significantly increased(P<0.01) and positively correlated with duration of stress (r=0.9750,P<0.01). Conclusion Stress promote apoptosis of gastric epithelium mucosae,apoptosis must participate the progress of lesion in gastric epithelium mucosae;stress cause plasma EGF decreased,the lesion may correlate with the lossed protection to gastric epithelium mucosae of endogenetic EGF.