Abnormalities in the ultradian oscillations of insulin secretion and glucose levels in type 2 (non-insulin-dependent) diabetic patients

Diabetologia. 1992 Jul;35(7):681-9. doi: 10.1007/BF00400263.

Abstract

To investigate the temporal organization of insulin secretion and glucose concentration during fasting in Type 2 (non-insulin-dependent) diabetes mellitus, we studied seven patients with Type 2 diabetes, eight obese non-diabetic control subjects and eight normal weight non-diabetic subjects. Blood sampling for glucose, insulin and C-peptide was performed at 15-min intervals during a 24-h period of fasting for the diabetic and the obese control subjects and during an 8-h fasting period for the normal subjects. Insulin secretion rates were calculated from the peripheral C-peptide concentration profiles. Ultradian oscillations of glucose levels and insulin secretion rates were evident during fasting in all subjects. An additional study with blood sampling at 2-min intervals for 8 h further indicated that this ultradian periodicity is expressed independently of rapid 10-15 min insulin oscillations. There were no differences between diabetic and non-diabetic subjects in the frequency of the ultradian oscillations of insulin secretion (which averaged 12-15 oscillations per 24 h) and in the rate of concomitancy of oscillations of insulin secretion with oscillations in glucose levels, which averaged 63-65%. The relative amplitudes of both the insulin and glucose oscillations were also similar in diabetic and nondiabetic subjects. The major abnormality in patients with Type 2 diabetes was evidenced by spectral analysis, and confirmed by calculations of the distributions of inter-pulse intervals. It consisted of a slowing of the glucose oscillations, without a similar slowing of the oscillations in insulin secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Activity Cycles*
  • Blood Glucose / metabolism*
  • C-Peptide / blood
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / physiopathology*
  • Fasting
  • Female
  • Humans
  • Insulin / blood
  • Insulin / metabolism*
  • Insulin Secretion
  • Male
  • Middle Aged
  • Obesity / blood
  • Obesity / physiopathology
  • Reference Values

Substances

  • Blood Glucose
  • C-Peptide
  • Insulin