Igf-i alters skeletal muscle substrate metabolism and blunts
recovery from insulin-induced hypoglycemia.
Hussain, Mehboob A., Ole Schmitz, Jens. S. Christiansen, Niels J.
Christensen, K. George M. M. Alberti, and E. Rudolf Froesch.
Division of Endocrinology and Metabolism, Department of Internal
Medicine, University Hospital of Z[umlaut]urich, Switzerland, Second
University Clinic of Internal Medicine, Aarhus, Denmark, Department
of Endocrinology, Herlev Hospital, University of Copenhagen, Denmark,
Human Diabetes and Metabolism Research Centre, Department of
Medicine, University of Newcastle, Newcastle Upon Tyne, England
APStracts 2:0215E, 1995.
Eight healthy subjects were treated with saline or insulin like growth
factor-I (IGF-I, 10[mu]g/kg x h, sc.) for three days in a crossover
randomized fashion. Substrate balances across the forearm skeletal
vascular bed were determined in the postabsorptive state and during a
hyperinsulinemic, euglycemic clamp. In the basal state net forearm
uptake of free fatty acids and ketone bodies were increased during
IGF-I administration in the face of elevated plasma levels of these
substrates, whereas basal glucose levels and forearm glucose balance
were unchanged. However, whole body and net forearm glucose uptake
was more makredly stimulated by insulin (+20% and +8%, respectively)
in the IGF-I period. Additionally, counter-regulatory hormone
responses were examined during insulin-induced stepwise hypoglycemia.
Responses of growth hormone and glucagon were blunted, those of
cortisol and epinephrine more marked and that of norepineprine
unchanged during IGF-I administration. These changes were accompanied
with delayed recovery from hypoglycemia.
Received 27 June 1995; accepted in final form 12 October 1995.
APS Manuscript Number E296-5.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 November 95