An assessment of gastric ulcers in vivo: enhancement of urinary recovery after oral administration of phenolsulfonphthalein in rats.

Abstract

The permeability of gastric wall barrier to phenolsulfonphthalein (phenol red), a poorly absorbed drug, was examined as an index of an assessment of gastric mucosal damages in vivo. The urinary recovery after oral administration of phenol red and the ulcer index of the stomach were significantly increased in rats subjected to restraint and water immersion stress. Gastric absorption of phenol red, examined by means of in situ loop technique, was increased significantly in stressed rats. However, the urinary recovery of the dye after intravenous administration did not change in ulcerated rats compared with the control. These findings suggest that the increase in the urinary recovery of phenol red is due to the increased gastric absorption. The healing period of 12 d was enough to restore to control levels both the ulcer index and the urinary recovery of the dye. Both indices remained nearly at control level by the pretreatment with atropine sulfate. Good correlation between extent of gastric damage and urinary excretion of phenol red was obtained within single groups of animals. This method may be utilized as a simple and noninvasive screening test for an assessment of gastric mucosal damages in vivo.