Effects of the elevation of serum bile acids on gastric mucosal damage

In this study, we evaluated whether the elevated serum level of bile acids was a trigger of gastric mucosal damage in rats. A degree of mucosal injury was evaluated as an extent of ulcer formation due to HCl. That is, 0.6 N H Cl was administered to the stomach via a tube in a rat model 3 h after liga tion of the common bile duct, with additional infusion of four different bi le acids. Taurocholic acid (TCA), taurodeoxycholic acid (TDCA), taurochenod eoxycholic acid (TCDCA) and tauroursodeoxycholic acid (TUDCA) were used as bile acid samples and saline was administered to rats as a control. Moreove r, gastric mucosal blood Row and gastric content of epidermal growth factor (EGF), were evaluated in rats with severe mucosal damage. As a result, sig nificant mucosal damage was detected in rats administered TDCA or TCDCA com pared to controls. Gastric mucosal blood flow did not change, but the EGF l evel was significantly decreased by bile duct obstruction with TDCA infusio n. These data indicate that gastric mucosal injury was readily induced by a n elevated serum level of TDCA, TCDCA and their unconjugated bile salts and this effect was directly due to cytotoxicity of the bile acid. (C) 1999 El sevier Science Ireland Ltd. All rights reserved.