AJP - Regulatory, Integrative and Comparative Physiology, Vol 253, Issue 1 55-R63, Copyright © 1987 by American Physiological Society
3-O-methylglucose transport in soleus muscle of bacteremic rats
M. V. Westfall and M. M. Sayeed
Basal and insulin-stimulated soleus muscle 3-O-[14C]methylglucose
([14C]-3-O-MG) transport was studied in vitro and in vivo during bacteremia
in rats. Fasted rats were injected with Escherichia coli to produce
bacteremia (B), and controls (C) received saline. In vitro studies using
soleus muscles were carried out 8 or 12 h after bacterial injection, and
transport was measured using the rate coefficient (lambda = min-1).
Although insulin-stimulated (10 mU/ml) [14C]-3-O-MG transport was decreased
in 12-h bacteremic rat muscles (lambda B = 0.041 +/- 0.003; lambda C =
0.055 +/- 0.002), the basal [14C]-3-O-MG transport rate coefficient was
elevated (lambda B = 0.027 +/- 0.004; lambda C = 0.019 +/- 0.001). For in
vivo studies, [14C]-3-O-MG with or without insulin was injected into rats
10-40 min prior to removing soleus muscles at 12 h postbacterial or
postsaline injection. Transport was measured as the ratio of
[14C]-3-O-MGintracell/[14C]-3-O-MGextracell. Basal ratios were not
different and muscles from both control and bacteremic rats responded
comparably to insulin with increased [14C]-3-O-MG transport during the
initial 30 min. At 35-40 min postinsulin injection there was a further
stimulation of [14C]-3-O-MG transport in control but not in 12-h bacteremic
rat muscles. The changes in [14C]-3-O-MG transport observed in vitro and in
vivo after 12 h of bacteremia may be due to circulating mediators and/or
changes in membrane function.
