Response of gastric inhibitory polypeptide (GIP) to test meal in chronic pancreatitis--relationship to endocrine and exocrine insufficiency.

Twenty-nine patients with chronic pancreatitis had a significantly greater IR-GIP response to a test meal than 15 controls. This increased response was not related to the degree of steatorrhoea or glucose intolerance. It was most marked in a group of patients with moderately impaired IRI release and medium steatorrhoea. From this is concluded that the IR-GIP response to a test meal is determined by at least two factors: 1. feedback control via insulin secretion, 2. assimilation of fat. In chronic pancreatitis endocrine insufficiency may induce an exaggerated GIP response and severe exocrine insufficiency may prevent fat induced GIP release. Gastrin is not involved in the different GIP response in patients with chronic pancreatitis.