In vivo metabolic action of insulin-like growth factor I in adult rats

Diabetologia. 1991 Mar;34(3):144-9. doi: 10.1007/BF00418267.

Abstract

The acute metabolic actions of insulin-like growth factor I were studied in anaesthetized adult rats and its potency was compared to that of insulin. Following an i.v. bolus injection of insulin-like growth factor I a dose-dependent decrease of blood glucose and serum non-esterified fatty acid concentrations was noted with a potency of about 2% that of insulin. Stimulation of total body glucose disposal during euglycaemic clamping required approximately 50 times higher insulin-like growth factor I serum concentrations to achieve an identical half-maximal response. A similar difference in potency was observed for the stimulatory action on 2-deoxyglucose uptake and on glycogen formation in skeletal muscle. Lipogenesis in epididymal fat pads was increased dose-dependently by both hormones requiring approximately 30 times higher half-maximally effective serum concentrations of insulin-like growth factor I. These data demonstrate that insulin-like growth factor I exerted acute insulin-like metabolic actions in vivo with low potency. These effects were probably mediated via insulin receptors. A preferential stimulation of glucose metabolism in skeletal muscle was not observed.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipose Tissue / drug effects
  • Adipose Tissue / metabolism*
  • Animals
  • Blood Glucose / metabolism
  • Brain / drug effects
  • Brain / metabolism*
  • Fatty Acids, Nonesterified / blood
  • Glucose / metabolism*
  • Glucose Clamp Technique
  • Glycogen / biosynthesis
  • Insulin / pharmacology*
  • Insulin-Like Growth Factor I / pharmacology*
  • Kinetics
  • Lipolysis / drug effects*
  • Liver Glycogen / metabolism
  • Male
  • Muscles / drug effects
  • Muscles / metabolism*
  • Organ Specificity
  • Rats
  • Rats, Inbred Strains

Substances

  • Blood Glucose
  • Fatty Acids, Nonesterified
  • Insulin
  • Liver Glycogen
  • Insulin-Like Growth Factor I
  • Glycogen
  • Glucose