Annals of medicine
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Review Comparative Study
Differences in lipolysis between human subcutaneous and omental adipose tissues.
Hydrolysis of triglycerides to fatty acids and glycerol in fat cells (lipolysis) is of importance for the control of lipid and carbohydrate metabolism. This process is regulated by several hormones and parahormones acting on cyclic AMP formation or breakdown, which in turn influences the activity of hormone sensitive lipase. The latter enzyme stimulates hydrolysis of triglycerides in fat cells. ⋯ The antilipolytic insulin receptors, alpha 2 adrenoceptors and adenosine receptors are most active in the subcutaneous fat cells. In subjects with upper-body obesity the regional variations in the action of catecholamines on lipolysis are further enhanced. Decreased action of beta 2-adrenergic receptors and increased activity of alpha 2-adrenergic adrenoceptors in combination with defects in hormone sensitive lipase function inhibits the lipolytic effect of catecholamines in subcutaneous fat cells whereas increased activity of beta 3-adrenergic receptors and decreased activity of alpha 2 adrenoceptors augment the lipolytic response in visceral fat cells.(ABSTRACT TRUNCATED AT 250 WORDS)