A, ratio of GluR1 phosphorylated at Ser-831 (S831) to total GluR1 is significantly increased 5 min after contextual fear conditioning training (FC; n = 8; *, p < 0.05). B, ratio of GluR1 phosphorylated at Ser-845 to total GluR1 is increased, although not significantly (n.s.), 5 min after contextual fear conditioning training (n = 11, p = 0.21). C and D, example immunoblots for A and B. E, GluR1 phosphorylation at Ser-831 (P-S831) is back to control levels 2 h after contextual fear conditioning training (n = 8). F, no change in GluR1 phosphorylation at Ser-845 2 h after contextual fear conditioning training (n = 8). G and H, example blots for E and F labeled as in C and D.