The effect of ethanol and bile on electrolyte movement across canine proximal duodenal mucosa

The existence of a gastric mucosal barrier, controlling H+ N+ flux has been well established. The disruption of this barrier by ethanol and bile has also been confirmed. This study was designed to investigate the effect of ethanol and bile on the duodenal mucosa, which, as we have shown, is similar to gastric mucosa in that there is H+, Na+ flux. In 10 dogs, duodenal explants with an intact blood supply were placed within lucite chambers. Under basal conditions there was H+ insorption and Na+ exsorption. Neither bile nor ethanol caused increased H+ Na+ flux. Acute erosions did not develop in the proximal duodenum, as has been shown to occur when bile or ethanol is instilled into the stomach. These studies, therefore, demonstrate that although H+ Na+ occurs across the duodenal mucosa, bile or ethanol do not cause changes in ionic flux and acute erosions do not develop.