十二指肠胃反流对胃黏膜损害的实验性研究

目的：拟通过大鼠实验模型探讨短期十二指肠胃反流(DGR)对胃黏膜的损害及其特点。方法：健康、雄性SD大鼠分成3组：DGR组、结扎幽门组和对照组。手术后3周处死大鼠,观察胃黏膜损害及病理组织学改变、检测胃液pH值、胆红素水平及血清胃泌素水平,透射电镜下观察胃窦黏膜细胞间的紧密连接,测定组织过氧化物酶(MPO)活性。结果：DGR组大鼠胃黏膜可见散在糜烂、溃疡及出血点,而结扎幽门组及对照组胃黏膜光滑。DGR组胃液pH值和胆红素水平明显高于结扎幽门组及对照组,但血清胃泌素水平未见显著升高。短期DGR可引起胃窦黏膜胃小凹增生,没有肠上皮化生及胃黏膜萎缩等。短期DGR炎性细胞浸润不明显,没有导致组织MPO的水平改变,可引起黏膜细胞间的紧密连接受损。结论：DGR短期内可造成胃黏膜损害,表现为胃小凹增生、细胞间紧密连接受损,但炎性细胞浸润不明显,也不引起MPO活性的变化。

An experimental study on gastric mucosal damage induced by duodenogastric reflux in rats

Objective Duodenogastric reflux (DGR) is an important factor causing gastric mucosal damage, but whether short-term DGR cause gastric damage and its characteristics remain unclear. The aim of the study is to investigate the damage of gastric mucosa and its characteristics due to short-term DGR in a rat model. Methods Healthy, male SD rats were divided into three groups: a DGR group, a pylorus ligation group and a control group. The rats were sacrificed three weeks after the operation. The damage of gastric mucosa was observed macroscopically and microscopically. The pH value and bilirubin level of the gastric fluid were examined. The tight junctions between antral mucosal cells were evaluated under transmission electronmicroscopy. The serum gastrin concentration was investigated with radioimmune assay. Myeloperoxidase(MPO) was examined with chemical method. Results Macroscopically, there were significant mucosal lesions such as erosions, ulcers and bleeding spots in the DGR group. Microscopically, short-term DGR can cause faveolar hyperplasia ,but no apparent intestinal metaplasia and atrophy were observed. There was scarcely presence of acute and chronic inflammatory cell infiltration and MPO activity remained unchanged. The pH value and bilirubin level of gastric fluid increased significantly and the serum gastrin concentrations did not change a lot. Short-term DGR can cause destruction of tight junction, which was shorter in duration, less in deformation and might even disappear at the time of examination. Conclusions It is suggested that short-term DGR can induce gastric damage,faveolar hyperplasia and tight junction destruction without inflammatory cell infiltration and MPO activity changes.