大鼠胃损伤适应性作用的观察

Observation on gastric adaptation in rats

目的 建立大鼠无水乙醇胃损伤的适应模型 ,观察大鼠胃损伤适应性保护作用。方法 采用 40 %、75 %乙醇 1ml胃饲 ,并且在 0、2、4d内予以重复刺激 ,诱发胃损伤适应模型 ,观察损伤模型胃黏膜病理形态变化。结果 对照组大鼠胃黏膜损伤指数 (UI)为 47 2 5± 2 .0 5 ;40 %乙醇处理组大鼠胃黏膜UI为 2 5 .2 5± 3 .71,较对照大鼠显著降低 (P <0 .0 5 ) ;75 %乙醇处理组大鼠胃黏膜UI为 67.40± 10 .81,较对照大鼠显著增高 (P <0 .0 5 )。提示在给予 40 %乙醇 3次刺激后 ,大鼠胃能产生适应性保护作用 ,减轻了再给予无水乙醇刺激时的胃损伤 ;而在给予 75 %乙醇 3次刺激后 ,大鼠胃不能产生适应性保护作用 ,反而加重了再给予无水乙醇刺激时的胃损伤。

Objective To establish an ethanol-induced gastric adaptation model in rats and investigate the differences between 40% and 75% ethanol in occurrence of gastric adaptation and making the gastric mucosa develop the ability to defend itself against lesions.Methods Animal models of gastric mucosal damage were established by intragastric instillation of 40% and 75% ethanol respectively once every other day for three times in two animal groups.The surface of the erosive mucosa was observed by microscopy and histological analysis of mucosal appearance was performed under a light microscope.Results Gastric ulcer index (UI) in control rats was 47.25±2.05; UI in 40% ethanols-rats was 25.25±3.71, significantly lower than control rats (P<0.05); UI in 75% ethanols-rats was 67.40±10.81, significantly higher than control rats (P<0.05) . The stomach of the rats was able to adapt to repeated use of the relatively milder irritants such as 40% ethanol, then reduce the injury induced by administering absolute ethanol. Use of 75% ethanol for three times completely abolished gastric adaptation to the injury, which could account for the exacerbation of erosions after using absolute ethanol. Conclusion This study demonstrated that gastric adaptation should produce in a cenain irritant domain.