Morphometric studies of parietal cells during basal conditions and during stimulation with pentagastrin in healthy subjects

A morphometric study was carried out of parietal cells from seven healthy volunteers. Under gastroscopical control, biopsies were taken with a hydraulic capsule before and 30 min after stimulation with pentagastrin. No significant change was found in the absolute volume of the parietal cells or their nuclei during stimulation. When median values for the ultrastructure were compared, microvilli constituted 4.6% of the parietal cell volume during basal conditions and 9.3% during stimulation with pentagastrin. Tubulovesicular structures constituted 10.9% of the cell volume during basal conditions and 1.9% during stimulation. These ultrastructural differences between basal and stimulated conditions were statistically significant, with P = 0.02 using Wilcoxon's test for paired data. Similarly significant changes were found in the membrane area of the secretory canaliculus and the tubulovesicular structures.