Genetic inhibition of PKA in the adult impairs memory for contextual fear conditioning. A, TetO-R(AB) transgenic mice and wild-type littermates were raised on Dox-containing food to suppress R(AB) expression throughout development and until they became 8 weeks old. They were removed from Dox to induce R(AB) expression for 4 weeks before being trained and tested in fear conditioning (FC). B, Baseline freezing behavior in tetO-R(AB) transgenic mice (n = 8) and wild-type littermates (n = 8) (training, baseline) and during a test of short term memory for contextual fear conditioning (testing, 1 h test). C, Baseline freezing levels are shown for tetO-R(AB) transgenic mice (n = 13) and wild-type littermates (n = 11) (training, baseline) and during a test of long term memory (LTM) for contextual fear conditioning (testing, 24 h test). D, Baseline levels of freezing for tetO-R(AB) transgenic mice (n = 10) and wild-type littermates (n = 9) (training, baseline) and during a test of long term memory for cued fear conditioning performed 24 h later in a novel context (testing, 24 h test). Baseline freezing is that exhibited during the 2.28 s previous to the delivery of the footshock during fear conditioning. Error bars indicate SEM. *p < 0.05.