The Effect of Gastrin on Basal- and Glucose-Stimulated Insulin Secretion in Man

Abstract

A B S T R A C T The effect of gastrin on basal-and glucose-stimulated insulin secretion was studied in 32 normal, young subjects. The concentration of gastrin and insulin in serum was measured radioimmunochemically.Maximal physiologic limit for the concentration of gastrin in serum was of the order of 160 pmol per liter as observed during a protein-rich meal. Oral ingestion of 50 g glucose produced a small gastrin response from 28±3 to 39+5 pmol per liter (mean +SEM, P < 0.01).Intravenous injection or prolonged infusion of gastrin increased the concentration of insulin in peripheral venous blood to a maximum within 2 min followed by a decline to basal levels after a further 10 min. The The results indicate that gastrin can stimulate a rapid and short-lived release of insulin. In physiologic concentrations gastrin potentiates the glucose-stimulated insulin secretion and is without effect on basal insulin secretion. A small release of gastrin during oral glucose ingestion may to a limited extent contribute to the nonglycemic insulin secretion. During protein ingestion, gastrin probably stimulates insulin secretion significantly.This work was presented in part at the International Symposium on "The impact of insulin on metabolic pathways," 26 October 1971, Jerusalem, Israel.

Immunoassayable Gastric Inhibitory Polypeptide: Investigations into its Role in Carbohydrate Metabolism

“…It has long been recognised that hyperglycaemia alone cannot entirely account for the rise in plasma insulin observed after the ingestion of glucose (Elrick et al, 1964;Mcintyre et al, 1964). The gastrointestinal hormones gastrin, secretin, and CCK are all able to stimulate insulin secretion under certain conditions and in some species but it is doubtful whether they playa physiological role in influencing insulin secretion in response to oral stimuli (Sum and Preshaw, 1967;Rehfeld and Stadil, 1973;Bloom, 1974). Glucagon-like immunoreactive substances (GLI) of the gut may playa role (Marks and Turner, 1977), but the most likely gastrointestinal hormone to occupy such a position is currently thought to be GlP, and therefore the measurement of GIP levels could be of importance in clinical situations where insulin secretion is abnormal.…”

Effects of vasoactive intestinal polypeptide (VIP), secretin and gastrin on insulin secretion in the mouse

“…A stimulatory effect on basal as well as on glucose-induced insulin release after administration of gastrin to man and dog has previously been reported [1,2,21,[32][33][34]. Generally, higher plasma levels of gastrin than are seen under physiological conditions are necessary to obtain an insulin-releasing effect [1].…”

Metabolic effects of fenfluramine in obese diabetics.

“…On the seventh day in hospital an intravenous glucose tolerance test (IVGTT) (Lundbaek, 1962) including insulin determinations (Rehfeld & Stadil, 1973) was performed. Twenty-four hours later the growth hormone (0rskov, Thomsen & Yde, 1968) response to intravenous arginine was determined (Parker, Hammond & Daughaday, 1967).…”