[Studies of experimental model of reflux esophagitis in rats by ligature on both lower portion of duodenum and most of forestomach].

It has been well established that reflux of gastroduodenal contents causes reflux esophagitis. Experimental model of reflux esophagitis in rats was devised by 24hrs ligature on both lower portion of duodenum and most of forestomach. Erosion of esophageal mucosa and thickening of esophageal wall developed in macroscopic findings. Histologically, many neutrophils were found from lamina propria to muscular layer, mainly in lamina propria. Edema and thickening of submucosal layer developed in cases with 24hrs ligature. These severe inflammatory changes in submucosal layer suggested that it caused thickening of esophageal wall. Bile reflux was found in gastric contents of this model. No mucosal lesions were found in cases with ligature on lower portion of duodenum. Findings in this experimental model of reflux esophagitis suggested significant roles of gastric juice and bile acids in the pathogenesis of reflux esophagitis. This model was thought to be useful for studies of pathophysiology of reflux esophagitis caused by reflux of gastroduodenal contents.