A, FSK action on GABAergic transmission was suppressed by a membrane-impermeable PKA inhibitor PKI (6–22) amide added to the postsynaptic neurons through the whole-cell patch pipette. FSK (20µM) was focally applied as indicated. B, The graph shows suppression of the modulatory action of FSK by PKI amide and H-89. In all cases, 20µM FSK was applied for 30 sec. Student t-test, * P< 0.05, ** P< 0.01, *** P< 0.001. Number of replicates: 50µM H-89 (n=3), 200µM PKI (n=4), 400µM PKI (n=4).