APStracts 3:0247E, 1996.

Role of glycogen concentration and adrenaline on glucose uptake in rat epitrochlearis muscle. Jensen, Jrgen, Rune Aslesen, John L. Ivy, Odd Brrs. Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, P.O.Box 1105 Blindern, N-0317 Oslo, Norway, The Norwegian University of Sport and Physical Education, P.O.Box 4014, Ullev[angstrom]al Hageby, N-0806 Oslo, Norway, Exercise Physiology and Metabolism Laboratory, Department of Kinesiology, The University of Texas at Austin, Austin, Texas 78712, USA,Department of Clinical Chemistry, Ullev[angstrom]al Hospital, 0407 Oslo, Norway

APStracts 3:0247E, 1996.

The effect of diet manipulated variations in muscle glycogen concentration and adrenaline on glucose uptake were studied in epitrochlearis muscles from Wistar rats. Both basal and insulin stimulated glucose uptake (measured with a tracer amount of 2-[1,2 3H(N)]-deoxy-D-glucose) inversely correlated with initial glycogen concentration (glycogen concentration vs basal glucose uptake: Spearman's Rho=-0.76, n=84, p&LT;0.000001; glycogen concentration vs insulin stimulated glucose uptake: Spearman's Rho=-0.67, n=44; p&LT;0.00001). Two fasting-refeeding procedures were used that resulted in difference muscle glycogen concentrations, although similar treatment for the last 48 hours before the experiment. In the rats with the lower glycogen concentration, basal as well as insulin stimulated glucose uptake was elevated. The muscle glycogen concentration had no effect on adrenaline stimulated glycogenolysis. Adrenaline, however, was found to reduced basal glucose uptake in all groups. These results suggest that: 1) the glycogen concentration participates in the regulation of both basal and insulin stimulated glucose uptake in skeletal muscle, 2) the magnitude of adrenaline stimulated glycogen breakdown is independent of the glycogen concentration, and 3) adrenaline inhibits basal glucose uptake at all glycogen concentrations.

Received 12 August 1996; accepted in final form 19 November 1996.
APS Manuscript Number E393-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996