title: 8-(4-Chlorophenyl)thio-cyclic AMP is a potent inhibitor of the cyclic GMP-specific phosphodiesterase (PDE VA).
abstract: 8-(4-Chlorophenyl)thio-cyclic AMP (8-CPT-cAMP), extensively used as selective activator of cyclic AMP-dependent protein kinase, has been found to be a potent inhibitor of the cyclic GMP-specific phosphodiesterase (PDE VA). Indeed, 8-CPT-cAMP (IC50 = 0.9 microM) inhibited PDE VA with a potency identical to that of zaprinast. 8-CPT-cAMP was also metabolized by PDE VA at a rate half that of cyclic GMP. The cyclic GMP-inhibited phosphodiesterase (PDE III) (IC50 = 24 microM) and the cyclic AMP-specific phosphodiesterase (PDE IV) (IC50 = 25 microM) were also inhibited by 8-CPT-cAMP. In contrast, most of the other cAMP-derivative studies showed little inhibition of any phosphodiesterase isoenzyme. These observations provide further reasons why the mechanism of the physiological effects of 8-CPT-cAMP should be interpreted with caution.
authors.affiliation: SmithKline Beecham Pharmaceuticals, Welwyn, Herts, U.K.
authors.forename: B J
authors.initials: BJ
authors.lastname: Connolly
authors.forename: P B
authors.initials: PB
authors.lastname: Willits
authors.forename: B H
authors.initials: BH
authors.lastname: Warrington
authors.forename: K J
authors.initials: KJ
authors.lastname: Murray
mesh_terms: D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000037:antagonists & inhibitors*; D000242:Cyclic AMP / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D006152:Cyclic GMP / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D007527:Isoenzymes / Q000037:antagonists & inhibitors*; D007700:Kinetics; D008433:Mathematics; D011688:Purinones / Q000494:pharmacology; D013873:Thionucleotides / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D007527:Isoenzymes; D011688:Purinones; D013873:Thionucleotides; C015929:8-((4-chlorophenyl)thio)cyclic-3',5'-AMP; D000242:Cyclic AMP; D015106:3',5'-Cyclic-GMP Phosphodiesterases; C011145:zaprinast; D006152:Cyclic GMP