Effect of indomethacin on blood flow distribution in the stomach of cats with acute gastric ulcer.

An ulcer was induced in the anterior wall of the antrum of cats by local injection of acetic acid solution. Carbonized microspheres, 15 +/- microns in diameter, labelled with 141Ce, 46Sc, and 85Sr, were used to measure blood flow in different regions and layers of the stomach wall. The radioactivity of a blood reference sample and of tissue samples was determined, and the blood flow was calculated for each tissue sample. The blood flow distribution was determined before, 1/2 h, and 1 h after an intravenous infusion of indomethacin in a dose of 3 mg/kg. Two groups of anaesthetized animals were used: animals with a 24-h gastric ulcer and control animals 24 h after laparotomy. In the control animals indomethacin caused a mean reduction in gastric mucosal blood flow of approximately 50%. The flow reduction was about the same in different regions of the stomach. In the muscularis there was no change in blood flow after indomethacin. The blood flow was reduced in the duodenum and jejunum but not in the other intestinal organs studied. The blood pressure and cardiac output remained unchanged. In the ulcer group indomethacin caused about the same reduction in mucosal blood flow. However, the blood flow was reduced less in the ulcer region and tended to increase in the mucosa around the ulcer 1 h after indomethacin infusion.