(Rp)-8-pCPT-cGMPS, a novel cGMP-dependent protein kinase inhibitor.
In the present study, the inhibitory effect of the cGMP analog (Rp)-8-(para-chlorophenylthio)guanosine-3',5'-cyclic monophosphorothioate ((Rp)-8-pCPT-cGMPS) on the cGMP-dependent protein kinase-mediated protein phosphorylation in intact human platelets was investigated. In vitro phosphorylation experiments with the substrate kemptide demonstrated an inhibition of the cGMP-dependent protein kinase by (Rp)-8-pCPT-cGMPS with a Ki of 0.5 microM. In intact human platelets, (Rp)-8-pCPT-cGMPS antagonized the activation of the cGMP-dependent protein kinase by 8-pCPT-cGMP without affecting cAMP-dependent protein kinase or cGMP-regulated phosphodiesterases. The data obtained suggest that (Rp)-8-pCPT-cGMPS may be a useful tool for studying the role of cGMP in vitro and in intact cells.
Universität Würzburg, Labor für Klin. Biochemie, Germany.
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D000818:Animals; D001792:Blood Platelets / Q000187:drug effects / Q000201:enzymology; D015153:Blotting, Western; D002417:Cattle; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000494:pharmacology; D017869:Cyclic GMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D009842:Oligopeptides / Q000378:metabolism; D010766:Phosphorylation; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D013873:Thionucleotides / Q000037:antagonists & inhibitors / Q000494:pharmacology
D009842:Oligopeptides; D010975:Platelet Aggregation Inhibitors; D013873:Thionucleotides; C055656:8-((4-chlorophenyl)thio)cyclic-3',5'-GMP; C037642:kemptide; D017868:Cyclic AMP-Dependent Protein Kinases; D017869:Cyclic GMP-Dependent Protein Kinases; D006152:Cyclic GMP