A supplementary infusion of glucose-dependent insulinotropic polypeptide (GIP) with a meal does not significantly improve the beta cell response or glucose tolerance in type 2 diabetes mellitus.
Newly diagnosed, previously untreated patients with type 2 diabetes mellitus (n = 6) were studied on two separate days after overnight fasts. On each day they were given a 500-kcal mixed meal plus an infusion of either porcine glucose-dependent insulinotropic polypeptide (GIP) (0.75 pmol/kg/min) or control solution (CS) from 0 to 30 min in random order. Frequent measurements of plasma glucose, C-peptide, insulin and GIP concentrations were made. Fasting GIP levels were similar on both days. During the meal plus GIP infusion plasma GIP levels increased from a basal value of 7.6 +/- 1.5 pmol/1 to a peak of 88.6 +/- 5.4 pmol/1 at 30 min. Following the meal infusion of CS GIP increased from a fasting level of 10.3 +/- 1.2 pmol/1 to a significantly lower peak of 58.0 +/- 8.3 pmol/1 at 60 min. During the meal plus GIP infusion GIP levels were higher at 10-45 min and at 90 min (P less than 0.05-0.001). Fasting and postprandial glucose, C-peptide and insulin levels were, however, similar on both study day. A supplementary infusion of porcine GIP with a mixed meal did not significantly alter the beta cell response or glucose tolerance in this group of patients with type 2 diabetes mellitus.
Jones
I R
IR
Department of Medicine, University of Wales, Cardiff, U.K.
Owens
D R
DR
Vora
J
J
Luzio
S D
SD
Hayes
T M
TM
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D002096:C-Peptide / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D004435:Eating; D002149:Energy Intake; D005215:Fasting; D005749:Gastric Inhibitory Polypeptide / Q000097:blood / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011897:Random Allocation; D013552:Swine
D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin; D005749:Gastric Inhibitory Polypeptide