[Potential difference of the gastric mucosa in gastroduodenal disease. Relation with endoscopical and histologic findings]

Most studies of gastric transmucosal potential difference concern acute damage. We studied this phenomenon in 168 patients with different pathologic processes: erosive gastritis, duodenal and prepyloric ulcer, atrophic gastritis, gastric ulcer and normal controls. Ag-AgCl electrodes and Agar-KCl bridges were used to record potential differences. Biopsies were taken from gastric antrum and body and potential differences were related to endoscopic and histologic findings. Maximal values of -29.2 + 2 and -22.2 + 1.6 for body and antrum, respectively, were found in normals. Lowest values (-19.4 + 1.4 and -14.3 + 1.5, respectively) were found in gastric ulcer, with intermediate values for the other conditions. Normal histologic findings were associated to potentials of -31 + 2 and -20 + 3.1 whereas lower values were recorded in patients with moderate or severe atrophic changes. Our findings suggest a relation between mucosal atrophy and lower transmucosal potential differences.