Inhibition of porcine adipose tissue lipogenesis by beta-adrenergic agonists

1. Beta-adrenergic agonists were not effective inhibitors of lipogenesis in porcine adipose tissue slices in vitro; addition of theophylline permitted the inhibition. 2. Inhibition was increased to a greater extent by isoproterenol than epinephrine and was decreased by propranolol, therefore presumably via beta-adrenergic receptors. 3. Caffeine, isobutylmethylxanthine and theophylline all permitted inhibition of lipogenesis by beta-adrenergic agonists. 4. It is not clear whether the mechanism for this permissive action is via antagonism of the adenosine receptor, inhibition of cAMP phosphodiesterase or a combination of both. 5. Adenosine deaminase was weakly permissive, presumably through destruction of adenosine. Inhibition of lipogenesis was observed with glucose or acetate as lipogenic substrate and in the presence or absence of albumin.