Journal of Lipid Research, Vol 19, 729-736, Copyright © 1978 by Lipid Research, Inc.
Cyclic AMP metabolism in adipose tissue of exercise-trained rats
EW Askew, AL Hecker, VG Coppes and FB Stifel
Cyclic AMP metabolism in epididymal adipose tissue of exercise-trained rats
was examined to determine if training induced changes in cyclic AMP
production or inactivation. Beginning at 7 weeks of age, male rats were
physically trained by 12 weeks of treadmill running. Pair-fed control rats
remained sedentary in their cages for the duration of the experiment.
Tissue levels of cyclic AMP were measured in epididymal adipose tissue
slices incubated with norepinephrine. Adenyl cyclase was assayed in
adipocyte ghost cell prepartions and low-Km phosphodiesterase was assayed
in homogenates of adipose tissue. In response to norepinephrine
stimulation, tissue cyclic AMP levels were reduced in trained compared to
untrained rats. Training increased the ratio of activity of
phosphodiesterase relative to adenyl cyclase. The results of this study
indicate that cyclic AMP production in response to norepinephrine
stimulation is not increased by training and may even be reduced, implying
that adipose tissue cyclic AMP levels may be under a greater degree of
control in trained rats. Modulation of adipose tissue cyclic AMP levels may
function to regulate more closely the duration of lipolysis in
exercise-trained rats.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
