Gastric inhibitory polypeptide in acquired pancreatic diabetes: effects of insulin treatment.
Oral glucose tolerance tests were done in eight insulin-requiring pancreatic diabetic patients to study the effect of withdrawal of insulin treatment on gut hormone release. Basal levels of gastric inhibitory polypeptide (GIP), glucagon-like immunoreactivity, and immunoreactive glucagon levels rose on insulin withdrawal, more so in patients on short-acting insulin, and were lowered by insulin treatment. Insulin treatment did not affect the GIP, glucagon-like immunoreactivity, or IRG responses to oral glucose. Improved glucose tolerance was greater in patients receiving soluble insulin than in those receiving lente insulin, and there was a significant positive linear correlation between basal plasma GIP and blood glucose levels in these patients. Therefore, it is suggested that insulin treatment lowers basal hormones levels, possibly via a metabolic effect, whereas the hormone responses to oral glucose may be controlled by several factors unrelated to insulin administration or changes in glucose homeostasis.
D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D002908:Chronic Disease; D003920:Diabetes Mellitus / Q000188:drug therapy / Q000209:etiology*; D005749:Gastric Inhibitory Polypeptide / Q000378:metabolism*; D005768:Gastrointestinal Hormones / Q000378:metabolism*; D005934:Glucagon / Q000378:metabolism; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000627:therapeutic use*; D008875:Middle Aged; D010195:Pancreatitis / Q000150:complications*
D001786:Blood Glucose; D005768:Gastrointestinal Hormones; D007328:Insulin; D005749:Gastric Inhibitory Polypeptide; D005934:Glucagon