Lack of negative feed-back regulation of insulin on the responses of gastric inhibitory polypeptide, insulin, glucagon and pancreatic polypeptide to a meal in insulin treated diabetics.
The effect of insulin on the secretion of immunoreactive gastric inhibitory polypeptide, insulin (as measured by C-peptide), glucagon and pancreatic polypeptide during and after a test meal was examined in seven diabetic patients treated with high insulin doses (mean 1.12 +/- 0.12 IU/kg X 24 h) before and after a reduction of the insulin dose (to 0.62 +/- 0.04 IU/kg X 24 h, p less than 0.02). While plasma insulin concentrations were significantly higher on the higher dose, no significant differences were found in the responses of immunoreactive gastric inhibitory polypeptide, C-peptide, glucagon and pancreatic polypeptide to the two meals. Blood glucose concentrations were not significantly different at the two tests. It thus seems that insulin has no direct effect on the secretion of these substances after a meal in insulin-treated diabetics.
D000328:Adult; D000368:Aged; D002096:C-Peptide / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D005260:Female; D005502:Food; D005749:Gastric Inhibitory Polypeptide / Q000378:metabolism*; D005768:Gastrointestinal Hormones / Q000378:metabolism*; D005934:Glucagon / Q000378:metabolism*; D006706:Homeostasis; D006801:Humans; D007328:Insulin / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D010191:Pancreatic Polypeptide / Q000378:metabolism*
D002096:C-Peptide; D005768:Gastrointestinal Hormones; D007328:Insulin; D005749:Gastric Inhibitory Polypeptide; D010191:Pancreatic Polypeptide; D005934:Glucagon