Temporal patterns of colonic blood flow and tissue damage in an animal model of colitis.

This study tested the hypothesis that altered colonic blood flow may contribute to tissue damage during the development of colitis in the rabbit. This was achieved by using radioactive microspheres to measure colonic blood flow at various times after colitis induction with trinitrobenzene sulfonic acid. Significant colonic damage occurred 6 hours post colitis induction and persisted throughout the 5 day study. Blood flow to the muscularis propria and mucosa/muscularis mucosae compartments increased significantly from 5 minutes until one hour post induction. At 6 and 12 hours post induction colonic blood flow returned to control levels before increasing again from 24 to 96 hours. This second increase in flow was, however, predominantly in the mucosa/muscularis mucosae compartment. Blood flow in the stomach and non-gastrointestinal tissues did not change significantly at any time. These data demonstrate that increased colonic blood flow may be disrupted in the early stages of colitis and that this coincides with the onset of significant damage. It is concluded that maintenance of elevated colonic blood flow throughout the development of colitis may help to ameliorate subsequent tissue injury.