Rp-cAMPS sodium salt, a cAMP analog, is a potent, competitive cAMP-induced activation of cAMP-dependent PKA I and II (Kis of 12.5 µM and 4.5 µM, respectively) antagonist. Rp-cAMPS sodium salt is resistant to hydrolysis by phosphodiesterases[1][2][3][4][5][6].
A membrane-permeable competitive cAMP antagonist (Rp-cAMPS) that blocks PKA activation by binding to the regulatory subunits without dissociating the kinase holoenzyme also inhibits synaptic plasticity but has no effect on normal synaptic transmission[2].
Rp-cAMPS (10 μM, 15 min) decreases the monosynaptic EPSCs evoked at the PB-CeLC and BLA-CeLC synapses in slices from arthritic rats but not in control neurons from normal animals. The inhibitory effect of Rp-cAMPS is significant compared to predrug (ACSF) control values obtained in the same neurons[2].
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