Serum Gastrin and Gastric Acidity

Summary: The relationship between serum levels of gastrin and intragastric acidity was studied using an immunoassay for gastrin which was specific for the biologically active C-terminal sequence of the gastrin molecules.
Eighty-three combined serum gastrin and intragastric pH estimations were performed on 43 subjects (4 normal, 13 patients with gastric ulceration and 26 patients with duodenal ulceration). The serum gastrin response to gastric acidification by betazole hydrochloride was studied in 9 patients with duodenal ulceration.
There was a highly significant (P <0.001) negative correlation (r=-0.37) of serum gastrin on basal intragastric pH, i.e. the patients with the higher gastrin levels had lower intragastric pH. Gastric acidification by betazole hydrochloride suppressed the hyper-gastrinaemia associated with duodenal ulceration.
The correlation between serum gastrin and intragastric pH suggests that gastrin is a factor in maintaining basal gastric acid secretion. Suppression of the hypergastri-naemia associated with duodenal ulceration by gastric acidification is consistent with the concept of an increased vagal tone in these patients.