热休克蛋白70对肝硬化门静脉高压性胃病大鼠胃黏膜损伤的保护作用

背景:临床上重度门静脉高压性胃病(PHG)常可引起上消化道致命性大出血。热休克蛋白70(HSP70)是加强胃黏膜防御功能的主要热休克蛋白。目的:探讨HSP70对肝硬化PHG大鼠胃黏膜损伤的保护作用及其机制。方法:以CCl_4制备肝硬化PHG大鼠模型,实验分为正常对照组、PHG组和三组热处理组。以酶联免疫吸附测定(ELISA)检测胃黏膜HSP70和肿瘤坏死因子(TNF)-α水平,并观察胃黏膜病理变化。结果:与正常对照大鼠相比,PHG大鼠胃黏膜HSP70水平明显降低而TNF-α水平明显升高,胃黏膜出现明显病理损伤;热处理组正常大鼠胃黏膜HSP70水平明显升高,TNF-α水平无变化,胃黏膜无明显损伤。与PHG大鼠相比,热处理组PHG大鼠胃黏膜HSP70水平明显升高,TNF-α水平明显降低,胃黏膜损伤明显减轻。结论:HSP70能减轻肝硬化PHG大鼠胃黏膜损伤,其保护作用可能与胃黏膜TNF-α水平降低有关。

Protective Role of Heat Shock Protein 70 for Gastric Mucosal Lesions in Cirrhotic Rats with Portal Hypertensive Gastropathy

In clinical practice, serious portal hypertensive gastropathy （PHG） may induce fatal bleeding in upper digestive tract. Heat shock protein （HSP） 70 is a major HSP which protects gastric mucosa. Aims： To investigate the protective role of HSP70 for gastric mucosal lesions in cirrhotic rats with PHG. Methods： Model of liver cirrhosis with PHG in rats was established by CCl4. Rats were divided into normal control group, PHG group and three heat treatment groups. Levels of gastric mucosa HSP70 and tumor necrosis factor alpha （TNF-α） were determined by enzyme-linked immunosorbent assay （ELISA）. Meanwhile, the pathological changes of gastric mucosa were examined. Results： Compared with normal control rats, level of gastric mucosa HSP70 was decreased, TNF-α level was increased and gastric mucosal lesions appeared in rats with PHG; increased gastric mucosa HSP70 level was found in normal rats in heat treatment group, but no significant changes of TNF-α level and gastric mucosal lesions were observed. Compared with PHG rats, PHG rats in heat treatment group showed increased gastric mucosa HSP70 level, decreased TNF-α level and improved gastric mucosal lesions. Conclusions： HSP70 can alleviate gastric mucosal lesions in cirrhotic rats with PHG, and its protective role may be related to the reduction of gastric mucosa TNF-α.