Effects of insulin on diacylglycerol/protein kinase-C signalling and glucose transport in rat skeletal muscles in vivo and in vitro

Endocrinology. 1992 Jun;130(6):3345-55. doi: 10.1210/endo.130.6.1597146.

Abstract

Insulin treatment in vivo provoked rapid dose-related increases in diacylglycerol content and/or translocation of protein kinase-C (PKC) from cytosol to membranes in rat soleus and gastrocnemius muscles. These effects were apparent with 1) insulin doses that provoked submaximal and maximal increases in glucose utilization, and 2) glucose-stimulated endogenous insulin secretion. Insulin-stimulated PKC translocation was evident when PKC was assayed by 1) histone or protamine phosphorylation after PKC purification by Mono Q column chromatography, and 2) immunoblotting for PKC beta and PKC epsilon. Dose-related effects of insulin on PKC translocation were also observed in the rat soleus in vitro, and this was associated with increased phosphorylation of 40- and 80-kilodalton proteins, which were also phosphorylated by phorbol ester treatment. A role for diacylglycerol-PKC signalling in insulin-stimulated glucose transport was suggested by studies of [3H]2-deoxyglucose ([3H]2-DOG) uptake in the rat soleus in vitro in that 1) PKC translocation and 2-DOG uptake were correlated; and 2) stimulatory effects of insulin and phorbol esters on 2-DOG uptake were apparently nonadditive.

Publication types

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

MeSH terms

  • Animals
  • Blood Glucose / metabolism
  • Cell Membrane / enzymology
  • Chromatography, Affinity
  • Cytosol / enzymology
  • Deoxyglucose / metabolism*
  • Diglycerides / metabolism*
  • Dose-Response Relationship, Drug
  • Electrophoresis, Polyacrylamide Gel
  • Glucose / metabolism*
  • In Vitro Techniques
  • Insulin / blood
  • Insulin / pharmacology*
  • Isoenzymes / isolation & purification
  • Isoenzymes / metabolism*
  • Kinetics
  • Male
  • Molecular Weight
  • Muscle Proteins / metabolism
  • Muscles / drug effects
  • Muscles / metabolism*
  • Phosphates / metabolism
  • Phosphoproteins / isolation & purification
  • Phosphoproteins / metabolism
  • Phosphorylation
  • Protein Kinase C / isolation & purification
  • Protein Kinase C / metabolism*
  • Rats
  • Rats, Inbred Strains
  • Signal Transduction / drug effects*
  • Tetradecanoylphorbol Acetate

Substances

  • Blood Glucose
  • Diglycerides
  • Insulin
  • Isoenzymes
  • Muscle Proteins
  • Phosphates
  • Phosphoproteins
  • Deoxyglucose
  • Protein Kinase C
  • Glucose
  • Tetradecanoylphorbol Acetate