1993 Volume 14 Issue Supplement Pages 95-98
Mucosal blood flow is supposed to show a considerable heterogeneity among different sites in organs, however, there has been no good tool for evaluating this. In this study, using rat stomach, we examined the temporal and spacial alteration of blood flow during the development of ischemia-reperfusion-induced gastric damage by using two dimentional laser Doppler perfusion imager. Male Wistar rats 200-250g were used for the experiments. Under pentobarbital anesthesia, stomach was carefully pulled out and exposed under laser Doppler perfusion imager PIM 1.0 (Lisca Development AB) and scanned from the serosal and the mucosal sides. One ml of 0.1N HCl was instilled into the gastric lumen. Systemic arterial pressure was continuously monitored and blood was stepwisely withdrawn from the femoral artery to 80, 60, 40 and 20% of the control pressure. After that the mean systemic pressure was maintained about 20mmHg for 20min. The shed blood was then reinfused and the stomach was removed at 30min later. CV-6209, a PAF receptor antagonist, was intravenously administered at the dose of 0.1mg/kg 30min before the experiment. In control condition, the blood perfusion was uniformly good showing more than 7-8 P. U. throughout the stomach. During the process of gradual decrease in systemic pressure, the blood perfusion of body and antral portion was almost equally decreased, but the perfusion of area along the left gastric artery and prepyloric region was comparatively well preserved. Perfusion detected from mucosal side was more vulnerable to ischemia than the serosal perfusion. After reperfusion, transient hyperemia was observed, and then the hypoperfused area started to appear in the middle body portion of the stomach near the greater curvature, well corresponding to the formation of gastric mucosal damage. CV-6209 well prevented the decreased perfusion as well as the formation of mucosal damage. From these observations, it is concluded that gastric mucosal blood flow shows heterogeneity among different portion of stomach which may closely relate to the occurence of mucosal damage.
