Adenosine-theophylline interactions on the lipolytic response to beta-adrenergic agonists in porcine adipose tissue

1. Many beta-adrenergic agonists did not stimulate porcine adipose tissue slice lipolysis unless theophylline, an antagonist of the adenosine receptor was added to the incubation medium. 2. In contrast to previous results, theophylline itself was an effective lipolytic agonist in tissue from many pigs. 3. Lipolysis was partially inhibited by adenosine or phenylisopropyl adenosine. Lipolysis was marginally stimulated by adenosine deaminase or 8-phenyltheophylline. 4. The data suggest that the mechanism of theophylline stimulation of lipolysis was only partially through antagonism of the adenosine receptor.