Rp-8-Cl-cAMPS

Rp-8-Cl-cAMPS is a novel combination of the well accepted protein kinase inhibitor Rp-cAMPS with 8-chloro cyclic AMP, resulting in a membrane permeant cyclic AMP antagonist which is not metabolized by mammalian cyclic nucleotide phosphodiesterases.
Rp-8-Cl-cAMPS is about 1.3 times more lipophilic compared to 8-Cl-cAMP, and 1.7 times and 2.2 times more compared to Rp-cAMPS and cAMP respectively.
In contrast to common ATP-site inhibitors or to its parent compound Rp-cAMPS, Rp-8-Cl-cAMPS discriminates between both isozymes of protein kinase A, prefering type I¹³ and thus provides additional selectivity. By occupying cAMP binding sites Rp-8-Cl-cAMPS prevents the kinase holoenzyme from dissociation and thus from activation.
Due to this working principle preincubation of the inhibitor prior to the activation step is necessary for optimal results.