Regional difference in the healing process of colitis induced by 2,4,6-trinitrobenzene sulfonic acid in rats

We recently reported an improved method to induce colitis by 2,4,6-trinitrobenzene sulfonic acid. This method enabled us to induce colitis at appropriate regions. This study aimed to investigate the regional differences on the healing process of colitis in rats. Colitis was induced at the proximal, middle or distal colon. On Day 10, the size of colitis was large in the order of the middle, distal and proximal colon. Colitis of the proximal colon healed more rapidly than that of the middle colon. Prostaglandin E(2) generation in the normal colonic mucosa was measured. Prostaglandin E(2) generation correlated with sizes of colitis among three regions. It was found that there was the regional difference on the healing process of the colitis and prostaglandin E(2) generation may show the different protective integrity of the colonic mucosa from the fact that higher prostaglandin E(2) generation showed larger colitis size.