Response of truncated glucagon-like peptide-1 and gastric inhibitory polypeptide to glucose ingestion in non-insulin dependent diabetes mellitus. Effect of sulfonylurea therapy

Acta Diabetol. 1995 Oct;32(3):165-9. doi: 10.1007/BF00838486.


Gastric inhibitory polypeptide (tGIP) and truncated glucagon like peptide-1 (GLP-1) are potent gastrointestinal insulinotropic factors (incretin), are most released after a meal or ingestion of glucose in man and animals. To investigate whether sulfonylurea (SU) affects the secretion of incretin, the modulation of plasma GIP and tGLP-1 levels following glucose ingestion in non-insulin-dependent diabetic type 2 patients with or without SU therapy was studied. A 75-G oral glucose tolerance test (OGTT) was carried out on 9 healthy subjects (controls) and 18 patients with non-obese type 2, 9 of whom were treated by diet alone (NIDDM-diet) and the other 9 with SU (glibenclamide 2.5 mg or gliclazide 40 mg) once a day (NIDDM-SU). Plasma GIP was measured by radioimmunoassay (RIA) with R65 antibody, and GLP-1 was measured by RIA with N-terminal-directed antiserum R1043 (GLP-1NT) and C-terminal-directed antiserum R2337 (GLP-1CT). Following OGTT, plasma glucose, GIP, GLP-1NT, and GLP-1CT in type 2 patients increased more markedly than in controls, despite the lower response of insulin. However, there were no significant differences in plasma levels of these peptides between the NIDDM-diet and NIDDM-SU groups. Therefore, it is unlikely that SU is involved in the high response of GIP and GLP-1s to OGTT in type 2 patients.

MeSH terms

  • Administration, Oral
  • Adult
  • Blood Glucose / analysis
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / drug therapy
  • Female
  • Gastric Inhibitory Polypeptide / blood*
  • Glucagon / blood*
  • Glucagon-Like Peptide 1
  • Glucose / administration & dosage
  • Glucose / pharmacology*
  • Humans
  • Insulin / blood
  • Male
  • Peptide Fragments / blood*
  • Protein Precursors / blood*
  • Sulfonylurea Compounds / therapeutic use


  • Blood Glucose
  • Insulin
  • Peptide Fragments
  • Protein Precursors
  • Sulfonylurea Compounds
  • Gastric Inhibitory Polypeptide
  • Glucagon-Like Peptide 1
  • Glucagon
  • Glucose