8-bromo-beta-phenyl-1-n(2)-ethenoguanosine-3--5--cyclic-monophosphorothioate and 8-chloroadenosine-3--5--cyclic-monophosphorothioate

Visual experience during a critical period early in postnatal development can change connections within mammalian visual cortex. In a kitten at the peak of the critical period (approximately P28-42), brief monocular deprivation can lead to complete dominance by the open eye, an ocular dominance shift. This process is driven by activity from the eyes, and depends on N-methyl-D-aspartate (NMDA) receptor activation. The components of the intracellular signaling cascade underlying these changes have not all been identified. Here we show that inhibition of protein kinase A (PKA) by Rp-8-Cl-cAMPS blocks ocular dominance shifts that occur following monocular deprivation early in the critical period. Inhibition of protein kinase G by Rp-8-Br-PET-cGMPS had no effect, indicating a specificity for the PKA pathway. Enhancement of PKA activity late in the critical period with Sp-8-Cl-cAMPS did not increase plasticity. PKA is a necessary component of the pathway leading to cortical plasticity during the critical period.

Topics: Animals; Cats; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Enzyme Inhibitors; Functional Laterality; Neuronal Plasticity; Ocular Physiological Phenomena; Receptors, N-Methyl-D-Aspartate; Thionucleotides; Vision, Monocular; Visual Cortex