Effects of acutely infused pentagastrin and somatostatin on intestinal calcium absorption in humans.

The influence of gastrin on intestinal calcium absorption (CaA), serum/plasma insulin, glucagon, parathyroid hormone, calcitonin, glucose, calcium and protein was measured in healthy adult males. Intravenous infusion of pentagastrin (PG. 6 micrograms/kg/h) resulted in a slight decrease of CaA (53.5 +/- (SEM) 5.8% of administered tracer vs. saline control 67.4 +/- 3.4, p less than 0.05). To exclude the influence of hormones like insulin, glucagon and calcitonin stimulated by PG, somatostatin was infused in additional trials. From these experiments and the infusion of synthetic human gastrin-17 (250 ng/kg/h) into 2 subjects, we conclude that acute infusion of gastrin lowers CaA in man.