Increased lipolysis to beta-adrenergic stimulation after dehydroepiandrosterone treatment in rats.
Young adult male rats were treated with 4 mg dehydroepiandrosterone (DHEA)/100-g diet for 4 wk or were fed the same purified diet unadulterated (51 carbohydrate:20 fat: 23.5 protein; wt/wt). After 1 wk body weight and fat mass of the DHEA-fed rats were significantly less than the controls. By the end of week 3, fat-free mass of the DHEA rats was less than the controls. Neither food intake nor resting metabolism, measured by indirect calorimetry, was different between groups. Isolated epididymal adipocytes of DHEA rats were significantly smaller and isoproterenol (x 10(7) M) stimulation of glycerol release was 53% greater (P < 0.01) than the controls. Basal rate of glycerol release increased significantly for both groups in response to the adenosine inhibitor adenosine deaminase; there were no significant interaction effects. Inhibition of lipolysis by the adenosine analogue phenylisopropyladenosine was similar between groups. Findings support the hypothesis that DHEA reduces adiposity directly by increased lipolysis, but the mechanism of action does not involve a change in the antilipolytic function of adenosine.
Tagliaferro
A R
AR
Department of Animal and Nutritional Sciences, University of New Hampshire, Durham 03824, USA.
Ronan
A M
AM
Payne
J
J
Meeker
L D
LD
Tse
S
S
D000243:Adenosine Deaminase / Q000494:pharmacology; D017667:Adipocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D000273:Adipose Tissue / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002151:Calorimetry; D003687:Dehydroepiandrosterone / Q000494:pharmacology*; D004822:Epididymis; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D007668:Kidney; D007700:Kinetics; D008066:Lipolysis / Q000187:drug effects*; D008297:Male; D009929:Organ Size; D010660:Phenylisopropyladenosine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011943:Receptors, Adrenergic, beta / Q000502:physiology*; D013997:Time Factors
D005230:Fatty Acids, Nonesterified; D011943:Receptors, Adrenergic, beta; D010660:Phenylisopropyladenosine; D003687:Dehydroepiandrosterone; D000243:Adenosine Deaminase