AJP - Regulatory, Integrative and Comparative Physiology, Vol 255, Issue 2 226-R231, Copyright © 1988 by American Physiological Society
Lipoprotein lipase in white and brown adipose tissues of exercised rats fed a high-fat diet
Y. Deshaies, J. Arnold, J. Lalonde and D. Richard
Departement de Physiologie, Faculte de Medecine, Universite Laval, Quebec, Canada.
The combined effects of a high-fat-supplemented diet and exercise training
on serum lipids as well as on lipoprotein lipase activity in white and
brown adipose tissues of the rat were evaluated. Male Wistar rats were fed
ad libitum either a stock diet or the stock diet supplemented with food
items rich in fat. Half of each dietary group was submitted to daily
treadmill running for 35 days. Food intake and final body weight were
raised by the high-fat-supplemented diet and lowered by exercise training.
Postprandial serum triglycerides were not affected by diet or exercise,
whereas the latter decreased total cholesterol in the high-fat group only
(14%, P less than 0.01). Total lipoprotein lipase activity in white adipose
tissue was elevated (120%, P less than 0.01) by high-fat feeding, and this
increase was greatly reduced by concomitant exercise training. In brown
adipose tissue, however, the large elevation (104%, P less than 0.01) in
enzyme activity brought by the high-fat diet was unaltered by concomitant
training. Thus a high-fat-supplemented diet increased lipoprotein lipase
activity in both an energy-storing and a heat-producing tissue, and
exercise training was able to counteract this effect in white, but not in
brown, adipose tissue. These findings support the notion that the
regulation of lipoprotein lipase is tissue specific.
