二甲基甲酰胺吸入致大鼠急性胃损伤的研究

目的通过动物实验探讨二甲基甲酰胺（DMF）对大鼠胃黏膜急性损伤的机制。方法大鼠静式吸入不同浓度（1446．2mg／m^3，3212．3mg／m^3，6524．0mg／m^3）的二甲基甲酰胺气体，观测胃黏膜大体损伤情况、胃黏膜的病理改变及胃黏膜血流（GMBF）、黏膜结合黏液量、谷胱甘肽（GSH）、丙二醛（MDA）、前列腺素E2（PGE2）、胃泌素（Gas）等指标。结果3个浓度组均见胃黏膜出血、糜烂等明显损伤，黏膜结合黏液量降低；低浓度组胃黏膜内谷胱甘肽降低，低、中浓度组胃泌素降低（P〈0．05）；光镜下各浓度组均可见黏液减少，黏膜出血、充血明显，黏膜紊乱。透射电镜可见颈黏液细胞与壁细胞核破裂，核内物质溢出核外。结论二甲基甲酰胺使胃黏膜出血糜烂，可能是损害了颈黏液细胞，使其分泌黏液的能力降低，影响胃的黏液一黏膜屏障系统，并且使胃泌素分泌减少使其营养胃黏膜的作用减弱。

A study on gastric mucosal damage in rats caused by acute inhalation of dimethylformamide

Objective To study mechanisms of dimethylformamide(DMF)on acute gastric mucosal damage in rats.Method Wistar rats were exposed to DMF vapor by static inhalation at different concentrations((1 446.2) mg/m~3,(3 212.3) mg/m~3 and 6 524.0 mg/m~3,respectively).Pathological change in gastric mucosa was observed by gastric mucosal injury index.Gastric mucosal blood flow(GMBF),volume of gastric mucosa binding mucus secretion,and levels of glutathione(GSH),malonydialdehyde(MDA),prostaglandin 2(PGE_2)and gastrin were assessed.Result Gastric mucosal bleeding,obvious congestion and erosion,and decrease in mucus secretion could be seen under a light microscope in all groups with reduced volume of gastric mucosa binding mucus secretion.Level of GSH in group of low-dose DMF decreased and level of gastrin decreased significantly in groups of low-and medium-dose DMF(P<0.05).Broken nuclei in gastric parietal cells and mucus neck cells and leak of nuclear mass could be seen under electron microscope.Conclusion DMF may damage mucus neck cells and parietal cells causing reduction of their mucus secretion and destriction of gastric mucosa-mucus barrier system.Reduced gastrin secretion could also reduce its nutritional effect on gastric mucosa.