LIPOLYTIC EFFECTS OF BETA(1), BETA(2) AND BETA(3)-ADRENERGIC AGONISTSIN ISOLATED HUMAN FAT-CELLS FROM OMENTAL AND RETROPERITONEAL ADIPOSE TISSUES

The presence of beta(1)-and beta(2)-adrenoceptors has been clearly est ablished in human fat cells. There is some controversy about the prese nce and function of beta(3)-adrenoceptors. It is well established that there are marked regional variations in catecholamine-induced lipolys is. In this work the possibility that a beta(3)-adrenoceptor plays a s ignificant role in the control of lipid mobilization is studied and al so its importance in comparison to beta(1)- and beta(2)-adrenoceptors in isolated human fat cells, is evaluated, by measuring the in vitro l ipolysis induced by dobutamine, salbutamol, metaproterenol, BRL 37344 and CGP 12177A. Human adipocytes from omental and retroperitoneal fat deposits exhibited an ''atypical'' beta-adrenergic response but, given the small lipolytic effect initiated by BRL 37344 and CGP 12177A, the y are probably poorly equiped in functional beta(3)-adrenoceptors.