The effect of insulin-like growth factor II on glucose uptake and metabolism in rat skeletal muscle in vitro.
The effect of insulin-like growth factor II (IGF II) on the rates of lactate formation, glycogen synthesis and glucose transport in the presence of a range of concentrations of insulin were investigated using an isolated preparation of rat skeletal muscle. IGF II, at a concentration of 65 ng/ml, caused a small but significant increase in the rates of these processes at a basal physiological insulin concentration (10 muunits/ml), but was without effect in the presence of 1, 100, 1000 or 10,000 muunits of insulin/ml. Hence IGF II increased the insulin sensitivity of this tissue. This effect was removed if the incubation medium was supplemented with an equimolar concentration of IGF binding protein 1 (BP1). It is suggested that changes in the concentration of IGF II and/or BP1 may regulate glucose uptake and metabolism in skeletal muscle and have physiological significance in the control of blood glucose level.
Bevan
S J
SJ
Department of Biochemistry, University of Oxford, U.K.
Parry-Billings
M
M
Opara
E
E
Liu
C T
CT
Dunger
D B
DB
Newsholme
E A
EA
D000818:Animals; D001692:Biological Transport; D002352:Carrier Proteins / Q000494:pharmacology; D005947:Glucose / Q000378:metabolism*; D006003:Glycogen / Q000096:biosynthesis; D007328:Insulin / Q000502:physiology; D018969:Insulin-Like Growth Factor Binding Proteins; D007335:Insulin-Like Growth Factor II / Q000502:physiology*; D007700:Kinetics; D007773:Lactates / Q000096:biosynthesis; D019344:Lactic Acid; D008297:Male; D009132:Muscles / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011994:Recombinant Proteins / Q000494:pharmacology
D002352:Carrier Proteins; D007328:Insulin; D018969:Insulin-Like Growth Factor Binding Proteins; D007773:Lactates; D011994:Recombinant Proteins; D019344:Lactic Acid; D007335:Insulin-Like Growth Factor II; D006003:Glycogen; D005947:Glucose