Bile acid-induced gastric mucosal injury: significance of portal hypertension and mucosal capillary permeability.
Rats with portal vein occlusion (PVO) were studied to determine severity of taurocholate-induced gastric mucosal injury during portal hypertension and following its resolution by collaterals. During the portal hypertensive state, after intragastric taurocholate, PVO rats compared with sham-operated controls had significantly greater macroscopic damage (14 +/- 1 vs 3 +/- 1% of total mucosa) and histologic deep necrosis (25 +/- 4 vs 3 +/- 1% of mucosal length). Gastric mucosal capillary permeability was also significantly greater in PVO rats, as assessed by increased appearance of intravenous Evans blue dye in gastric wall and contents. After 21 days of PVO portal pressures returned to normal. At this time taurocholate-induced gastric mucosal damage and capillary leak became similar in PVO and sham-operated rats. It is concluded that the portal hypertensive state alone predisposes to severe gastric mucosal damage and capillary leak.