反流性食管炎模型大鼠食管组织病理学变化及对血管活性肠肽表达的影响

Pathological changes of esophageal tissue and expression of vasoactive intestinal peptide in rats with reflux esophagitis

目的观察反流性食管炎大鼠模型建立后大鼠食管病理学变化及对大鼠食管下括约肌血管活性肠肽(VIP)表达的影响。方法随机将60只成年SD大鼠分为正常组、模型3d组、模型2周组,每组20只,雌雄各半。模型3d组、模型2周组使用半幽门缝扎和贲门部分肌层切开术制作大鼠反流性食管炎模型,术后分别连续喂养3d和2周处死,观察食管壁病理学改变,采用免疫组化法测食管下括约肌中VIP表达量。结果正常组大鼠食管下段黏膜偶见少量炎细胞浸润,食管肌间神经丛神经节内神经元数目多于胶质细胞。模型3d组和模型2周组大鼠食管下段黏膜可见大量中性粒细胞浸润,其中黏膜层内浸润最明显,黏膜下神经丛中的神经细胞数显著减少,并伴有空泡变性;食管肌间神经元显著退行性变,神经胶质细胞内可见空泡变性及线粒体水肿;模型3d组及模型2周组大鼠食管黏膜光镜下的病理分级及积分比较差异均无统计学意义(P均>0.05);模型3d组和模型2周组的VIP表达量均明显低于正常组(P均<0.05),模型3d组与模型2周组比较差异无统计学意义(P>0.05)。结论反流性食管炎模型大鼠的食管组织呈明显炎症表现,并可造成食管下括约肌内VIP表达减少。

Objective It is to observe the pathological changes of esophageal and the expression of vasoactive intestinal peptide(VIP)in esophageal sphincter after establishment of rat model of reflux esophagitis.Methods Sixty adult Sprague-Dawley rats were randomly divided into normal group,3 day model group and 2 week model group,with 20 rats in each group,half male and half female.The models of reflux esophagitis were made by semi-pyloric suture and partial cardiotomy of the cardia in the 3 day model group and 2 week model group,the rats were sacrificed after feeding for 3 days and 2 weeks respectively,and the pathological changes of the esophageal wall were observed.The expression of VIP in the lower esophageal sphincter was measured by immunohistochemistry.Results In the normal group,a small amount of inflammatory cells infiltrated in the lower esophageal mucosa,the number of neurons in the esophageal plexus ganglia was more than that in glial cells.In the 3 day model group and 2 week model group,a large number of neutrophil infiltration was observed in the lower esophageal mucosa,and the infiltration in the mucosa was the most obvious,the number of nerve cells in the submucosal plexus was significantly reduced,accompanied by vacuolar degeneration;esophageal muscle interneurons were significantly degenerative,and vacuolar degeneration and mitochondrial edema were observed in glial cells.There was no significant difference in the pathological grades and scores under the light microscope of the esophageal mucosa between the 3 day model group and 2 week model group(P>0.05);the expression of VIP in 3 day model group and 2 week model group was significantly lower than that in normal group(P<0.05),but there was no significant difference between 3 day model group and 2 week model group(P>0.05).Conclusion The esophageal tissue of rats with reflux esophagitis shows obvious inflammation and can reduce the expression of VIP in the lower esophageal sphincter.