Glucocorticoid deprivation alters glucose uptake by muscle and
adipose tissues of gtg-obese mice in vivo.
Blair, Stephen C., Ian D. Caterson, and Gregory J. Cooney.
Department of Endocrinology, Royal Prince Alfred Hospital,
Camperdown N.S.W. 2050, AUSTRALIA
APStracts 2:0132E, 1995.
The effect of 1 week of glucocorticoid deprivation by surgical
adrenalectomy (ADX) on tissue [(U)-14C] 2-deoxyglucose (2-DG) uptake
and hepatic glucose production (HGP) was assessed in conscious,
catheterised mice 5 weeks after the induction of obesity with gold
thioglucose (GTG). Despite the prevailing hyperglycemia and
hyperinsulinemia, glucose uptake by heart, quadriceps muscle and
interscapular brown adipose tissue (BAT) of GTG-obese mice was
unchanged compared with controls suggesting that the hyperglycemia of
GTG-obese mice is able to compensate for the insulin resistance of
these tissues. In contrast, epididymal white adipose tissue (WAT) of
GTG-obese mice showed increased glucose uptake with hyperglycemia and
hyperinsulinemia. ADX decreased the hyperglycemia and lowered the
elevated glycogen content of the liver of GTG-obese mice. ADX reduced
glucose uptake by heart and WAT of control and GTG-obese mice
consistent with the concomitant decrease in insulinemia. Glucose
uptake by muscle of control and GTG-obese mice was not significantly
decreased following ADX despite the decrease in insulin and ADX
increased glucose uptake by BAT of GTG-obese mice suggesting
increased sympathetically mediated thermogenesis in this tissue. HGP
was increased in GTG-obese mice compared to controls and ADX
significantly reduced HGP in both GTG-obese and control mice. These
results suggest that the improved glucose tolerance of ADX GTG-obese
mice and ADX control mice is due to a decrease in HGP rather than an
increase in peripheral glucose uptake.
Received 29 March 1995; accepted in final form 6 June 1995.
APS Manuscript Number E147-5.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 July 1995.