Journal Article•
Effects of xanthine derivatives on lipolysis and on adenosine 3',5'-monophosphate phosphodiesterase activity.
01 Nov 1970-Molecular Pharmacology (American Society for Pharmacology and Experimental Therapeutics)-Vol. 6, Iss: 6, pp 597-603
TL;DR: Close correlation between these two activities strongly indicates that the lipolytic activity of the xanthine derivatives is a result of inhibition of cyclic AMP phosphodiesterase.
Abstract: The lipolytic potencies of 64 compounds, mostly xanthine derivatives, were determined in epididymal fat cells. Nine of the compounds of widely varying lipolytic potency were examined as inhibitors of cyclic AMP phosphodiesterase activity. Substantial lipolytic effects were seen at concentrations producing less than 20% inhibition of phosphodiesterase activity. The most active compound, 1-methyl-3-isobutylxanthine, was about 15 times more potent than theophylline in both systems. Over a 20-fold range of concentrations, there was close agreement between the lipolytic activities of the compounds and their activities as inhibitors of phosphodiesterase. The close correlation between these two activities strongly indicates that the lipolytic activity of the xanthine derivatives is a result of inhibition of cyclic AMP phosphodiesterase.
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TL;DR: This article reviews many of the more important aspects about the structure, cellular localization, and regulation of each family of phosphodiesterases and places particular emphasis on new information obtained in the last few years about how differential expression andregulation of individual phosphodiesters relate to their function(s) in the body.
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