Recent developments on lipolysis regulation in humans and discovery of a new lipolytic pathway

In man, the major hormones controlling the lipolytic function are insulin ( inhibition of lipolysis) and catecholamines (stimulation of lipolysis). Cat echolamines are of major importance for the regulation of lipid mobilizatio n in human adipose tissue and for the increase of non-esterified fatty acid supply to the working muscle, In vitro studies have shown that there are d ifferences in the catecholaminergic control of fat cells from various fat d eposits and a number of physiological and pathological alterations of catec holamine-induced lipolysis have been reported. Lipolytic resistance to cate cholamines has been reported in subcutaneous adipose tissue, the major fat depot in obese subjects, Multiple alterations in catecholamine signal trans duction pathways have been reported. In site microdialysis allows a physiol ogical exploration of adipose tissue biology. Recent data obtained on the c atecholaminergic regulation of lipolysis and lipid mobilization, using micr odialysis in humans, will be analysed, A potent lipolytic and lipomobilizin g effect of atrial natriuretic peptide has recently been discovered; the me chanisms of action and physiological relevance will also be discussed.