Exercise and the cAMP system in rat adipose tissue. I. Lipid mobilization

1981 ◽  
Vol 50 (2) ◽  
pp. 250-254 ◽  
Author(s):  
L. B. Oscai ◽  
R. A. Caruso ◽  
A. C. Wergeles ◽  
W. K. Palmer
Keyword(s):  
Adipose Tissue ◽  
Binding Capacity ◽  
Exercise Program ◽  
Treadmill Running ◽  
Hormone Sensitive Lipase ◽  
Male Rats ◽  
Tissue Slices ◽  
Hormone Sensitive ◽  
Camp System ◽  
Rat Adipose Tissue

Protein kinase (PK) and hormone-sensitive lipase (HSL) were measured at rest in adipose tissue of untrained male rats and in that of animals subjected to a strenuous program of treadmill running. Total amounts of PK activity (decreased from 860 +/- 104 to 474 +/- 53 pmol.min-1. (10(6) cells)-1 (P less than 0.01) as a result of exercise training. At the same time, binding capacity for adenosine 3',5'-cyclic monophosphate (cAMP) was elevated in the runners. These data suggest a functional loss in catalytic activity without a loss in binding capacity. In addition, the results provide evidence that the capacity of PK to activate HSL is reduced in adipocytes of physically trained rats. HSL activity was measured in both adipose tissue slices and isolated adipocytes. The results show that the levels of activity of HSL did not increase as a result of the running program. These results provide evidence that the lipolytic capacity of adipocytes of normal untrained male rats is sufficiently large to meet the increased demand for free fatty acids imposed by the exercise program without the need for an adaptive increase in HSL activity.

Effect of exercise on hormone-sensitive lipase activity in rat adipocytes

1976 ◽  
Vol 230 (2) ◽  
pp. 385-388 ◽  
Author(s):  
JA McGarr ◽  
LB Oscai ◽  
J Borensztajn
Keyword(s):  
Fatty Acids ◽  
Enzyme Activity ◽  
Adipose Tissue ◽  
Free Fatty Acids ◽  
Lipase Activity ◽  
Exercise Program ◽  
Treadmill Running ◽  
Hormone Sensitive Lipase ◽  
Hormone Sensitive ◽  
Fat Pads

Hormone-sensitive lipase activity was measured in adipocytes of rats subjected to a 12-wk program of treadmill running. Enzyme activity in the runners sacrificed immediately after exercise increased 2.5-fold (P less than 0.001) in tissue exposed to epinephrine and threefold (P less than 0.001) in tissue not exposed to epinephrine, when the results were expressed per gram of adipose tissue. Increases of almost the same magnitude were observed in runners sacrificed 24 h after their last bout of work. These significant increases in enzyme activity, however, were the result of a significant reduction in the size of cells in the epididymal fat pads of the exercisers compared with those of the freely eating sedentary animals (68.7 +/- 2.7 mum vs. 82.0 +/- 2.7 mum; P less than 0.01). When the results were expressed on a per-cell basis, therefore, hormone-sensitive lipase activity, assayed in the presence or absence of epinephrine, was unaffected by the exercise program. These results provide evidence that the lipolytic capacity of adipocytes of normal, untrained rats is sufficiently large to meet the increased demand for free fatty acids imposed by the exercise program without the need for an adaptive increase in enzyme activity.

Exercise and the cAMP system in rat adipose tissue II. Nucleotide catabolism

1981 ◽  
Vol 50 (2) ◽  
pp. 255-258 ◽  
Author(s):  
W. K. Palmer ◽  
C. A. Kalina ◽  
T. A. Studney ◽  
L. B. Oscai
Keyword(s):  
Adipose Tissue ◽  
Exercise Training ◽  
Physical Training ◽  
Treadmill Running ◽  
Male Rats ◽  
Tetraacetic Acid ◽  
Phosphodiesterase Activity ◽  
Similar Extent ◽  
Camp System ◽  
Rat Adipose Tissue

In this study the effect of exercise training on the adenosine 3',5'-cyclic monophosphate (cAMP) system of rat adipose tissue has been investigated. The basal amount of cAMP for the exercising rats was 0.179 +/- 0.021 nmol/10(6) cells, the same value as for the controls. Phosphodiesterase activities (low and high Km) remained unaffected as a result of the program of treadmill running. Kinetic constants for the low- and high-Km phosphodiesterases revealed that the affinity of the enzymes for substrate (cAMP) was unaltered by physical training. Finally, ethyleneglycol-bis(beta-aminoethylether)-N,N'-tetraacetic acid, possibly through its effect on calmodulin, stimulated or inhibited (depending on concentration) phosphodiesterase activity in the same direction and to a similar extent in extracts of adipose tissue from runners and controls. Taken together, these data clearly demonstrate the exercise training has no effect on the cAMP system of adipose tissue in male rats.

scholarly journals Hormone-sensitive lipase of rat adipose tissue. Purification and some properties.

1981 ◽  
Vol 256 (12) ◽  
pp. 6311-6320
Author(s):  
G. Fredrikson ◽  
P. Strålfors ◽  
N.O. Nilsson ◽  
P. Belfrage
Keyword(s):  
Adipose Tissue ◽  
Hormone Sensitive Lipase ◽  
Hormone Sensitive ◽  
Rat Adipose Tissue

A second form of hormone-sensitive lipase from rat adipose tissue homogenates

1972 ◽  
Vol 270 (1) ◽  
pp. 81-85 ◽  
Author(s):  
Ray C. Pittman ◽  
Eric Golanty ◽  
Daniel Steinberg
Keyword(s):  
Adipose Tissue ◽  
Hormone Sensitive Lipase ◽  
Tissue Homogenates ◽  
Hormone Sensitive ◽  
Rat Adipose Tissue

Hormone-sensitive lipase of rat adipose tissue correlation of activity with a protein of molecular weight 84 000

1980 ◽  
Vol 619 (2) ◽  
pp. 440-444 ◽  
Author(s):  
John C. Khoo ◽  
Lars Berglund ◽  
Dennis Jensen ◽  
Daniel Steinberg
Keyword(s):  
Molecular Weight ◽  
Adipose Tissue ◽  
Hormone Sensitive Lipase ◽  
Hormone Sensitive ◽  
Rat Adipose Tissue

scholarly journals Hormone-sensitive lipase of rat adipose tissue: Identification and some properties of the enzyme protein

FEBS Letters ◽  
1977 ◽  
Vol 75 (1-2) ◽  
pp. 259-264 ◽  
Author(s):  
P. Belfrage ◽  
B. Jergil ◽  
P. Strålfors ◽  
H. Tornqvist
Keyword(s):  
Adipose Tissue ◽  
Hormone Sensitive Lipase ◽  
Enzyme Protein ◽  
Tissue Identification ◽  
Hormone Sensitive ◽  
Rat Adipose Tissue
Sign in / Sign up

Export Citation Format

Share Document