Ultrastructure of parietal cells before and after proximal gastric vagotomy in duodenal ulcer patients.

In order to examine whether the reduced acid secretion observed after proximal gastric vagotomy (PGV) is accompanied by intracellular changes in parietal cells, the ultrastructure of parietal cells before and after PGV has been studied in four duodenal ulcer patients. A stereological analysis of electron micrographs shows that after PGV there is a reduction in the volume density of microvilli and the surface density of canalicular membranes. Ten days after PGV there is a temporary increase in the surface density of tubulovesicular membranes. However, 3 months after the operation most of this membrane material has been removed so that the surface density of tubulovesicles at this late stage is only insignificantly higher than before the operation. The relative volume of dense bodies is more than doubled 3 months after PGV, and the observed removal of tubulo-vesicular membranes between the 10 days and the 3 months stage may therefore be due to lysosomal activity.