Does antral distension inhibit gastric acid secretion or stimulate bicarbonate secretion in 'healthy' subjects?
The effects of a 150-ml antral balloon distension on pentagastrin-stimulated gastric acid secretion and bicarbonate secretion were studied in nine healthy subjects and eight duodenal ulcer (DU) patients. The gastric secretions were simultaneously measured, using a luminal perfusion and pH/PCO2 measurements. Two of the healthy subjects and six of the DU patients were positive for Helicobacter pylori. When H. pylori-positive and -negative subjects were compared, basal gastric acid and bicarbonate outputs did not differ significantly. In H. pylori-infected subjects the bicarbonate transport increased by about 70% on pentagastrin stimulation. In the H. pylori-negative group pentagastrin had no effect on the bicarbonate secretion. Antral distension elicited a 30-35% inhibition of pentagastrin-stimulated gastric acid secretion in the group of H. pylori-negative subjects, whereas the acid secretory level remained essentially unchanged in the positive group. Bicarbonate secretion decreased transiently by the distension in the negative subjects, whereas a slight increase was observed in the infected group. We conclude that antral distension inhibits pentagastrin-stimulated gastric acid output in healthy H. pylori-negative subjects. Our results strongly suggest that the underlying mechanism is a direct inhibition of gastric parietal cell function and not an increased gastric bicarbonate secretion. Furthermore, the results indicate that this defective distension-induced acid inhibition may be correlated to H. pylori infection rather than to duodenal ulcer disease.
Hamlet
A
A
Dept. of Physiology, University of Gothenburg, Sweden.
Dalenbäck
J
J
Olbe
L
L
Fändriks
L
L
D000328:Adult; D000368:Aged; D001639:Bicarbonates / Q000378:metabolism*; D002404:Catheterization; D004381:Duodenal Ulcer / Q000378:metabolism* / Q000382:microbiology / Q000628:therapy; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D016481:Helicobacter Infections / Q000378:metabolism* / Q000382:microbiology / Q000628:therapy; D016480:Helicobacter pylori; D006801:Humans; D007441:Intubation, Gastrointestinal; D008297:Male; D008875:Middle Aged; D010295:Parietal Cells, Gastric / Q000378:metabolism; D010418:Pentagastrin / Q000494:pharmacology; D011706:Pyloric Antrum / Q000187:drug effects / Q000378:metabolism*
D001639:Bicarbonates; D010418:Pentagastrin