The effect of somatostatin on serum group I pepsinogens (PG I), serum gastrin, and gastric H+ and pepsin secretion in man.

Abstract

Six healthy young males were studied with an intravenous infusion of saline for 1 h, followed by somatostatin, 100 microgram/h, for 2 h, and thereafter by another 2 h with saline infusion. Gastric H+ and pepsin outputs were determined in 30-min periods throughout the study. Blood was drawn at regular intervals, and blood glucose was determined by a hexokinase method. PG I and gastrin in serum were determined by radioimmunoassay methods. Gastric H+ and pepsin outputs were markedly reduced during the somatostatin infusion and the first 30-min period after cessation of the somatostatin infusion. In the subsequent 60-min period gastric pepsin secretion increased significantly as compared with the basal period, whereas the gastric H+ output only increased non-significantly. Mean serum PG I increased during the somatostatin infusion and remained elevated throughout the study. The rise in serum PG I was marked in five and only marginal in the sixth person. Serum gastrin fell during the somatostation infusion and returned to the basal level thereafter. Blood glucose, on the other hand, fell only during the first 90 min of somatostatin infusion, and then climbed to the basal level, where it stayed for the remaining part of the study. The present results suggest that the pepsinogen synthesis is unaffected by somatostatin, and that serum PG I seems to reflect the amount of pepsinogens stored in the gastric mucosa.