Mural collagen in experimental reflux esophagitis in rats

Changes in the collagen content of the esophageal wall in reflux esophagitis were studied in rats subjected to surgically induced and biochemically monitored pancreaticobiliary reflux into the esophagus. Reflux periods of 7, 14, 28, and 42 days were followed by a reflux-abolishing operation, which resulted in healing of the esophagitis. The collagen content of the esophageal wall at the end of the reflux period was higher than control values obtained from normal nonoperated rats, with a significant difference after 42 days of reflux. Strictures were not observed. After abolition of the reflux the esophageal collagen content showed an initial drop, but then increased with the period of observation to give a significant rise (P less than 0.05) as compared with control rats which had been subjected to 7, 28, and 42 days of reflux. The meaning of the results for the understanding of the sequelae of reflux esophagitis is discussed.