Regional variation in adipose tissue lipolysis in lean and obese men.
Biopsies of adipose tissue were obtained from two subcutaneous regions (abdominal and femoral) in a sample of 54 men (32 obese and 22 lean subjects). Clonidine-induced antilipolysis in femoral adipose cells was similar in both groups, whereas subcutaneous abdominal adipocytes of obese individuals showed a higher alpha 2-adrenergic response than did subcutaneous abdominal adipose cells from lean subjects. In addition, epinephrine had a biphasic effect in subcutaneous abdominal adipocytes from obese individuals, as it induced antilipolysis at low concentrations, and a net lipolytic response at higher doses. In contrast, the physiological amine promoted lipolysis in subcutaneous abdominal adipose cells of lean subjects. Epinephrine- and clonidine-induced antilipolysis of subcutaneous abdominal adipocytes was positively associated with the level of subcutaneous abdominal fat measured by computed tomography (CT). Finally, men with a high alpha 2-adrenergic response of subcutaneous abdominal fat cells were fatter than those with a low alpha 2-adrenergic component. These results suggest that, in men with a wide range of body fatness, variations in the lipolytic response of subcutaneous abdominal adipose cells to epinephrine appear to involve changes in the functional balance between alpha 2- and beta-adrenoceptors.
Mauriège
P
P
Physical Activity Sciences Laboratory, PEPS, Laval University, Ste-Foy, Québec, Canada.
Després
J P
JP
Prud'homme
D
D
Pouliot
M C
MC
Marcotte
M
M
Tremblay
A
A
Bouchard
C
C
D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000328:Adult; D001823:Body Composition; D003000:Clonidine / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D008066:Lipolysis; D008297:Male; D009765:Obesity / Q000378:metabolism*
D007545:Isoproterenol; D003000:Clonidine; D004837:Epinephrine