Parietal cell sensitivity in humans: control and duodenal ulcer subjects, smokers and non-smokers

OBJECTIVETo determine (1) the respective contributions, if any, of parietal cell mass and parietal cell sensitivity to the increased maximal gastric secretion of patients with duodenal ulcer compared with control subjects; (2) the effect of smoking on parietal cell sensitivity, and (3) the mechanism of increased basal secretion in patients with duodenal ulcer. DESIGNMeasurement of gastric secretion rates in basal circumstances and in response to varying levels of stimulation, including maximal, in control subjects and in patients with duodenal uicer. METHODSGastric secretion studies were performed in 126 control subjects and 221 patients with duodenal ulcer. Secretion in response to 0.04 mg/kg/h histamine acid phosphate by intravenous infusion was measured in all subjects, in response to histamine at a quarter of that dose rate in 30 control subjects and in 30 patients with duodenal ulcer, at an eighth of that dose rate in eight controls and 14 patients with duodenal ulcer, and in basal circumstances in 45 controls and 106 patients. RESULTSThere were no differences in parietal cell sensitivity between control subjects and patients with duodenal ulcer, or between smokers and non-smokers. Basal secretion as a proportion of maximal secretion was the same in duodenal ulcer patients and controls. CONCLUSIONParietal cell sensitivity plays no part in hypersecretion in duodenal ulcer patients compared with controls, or in smokers compared with non-smokers; there is no basal hyperstimulation (‘vagal drive’) in patients with duodenal ulcer.