(A) Immunohistochemical analyses and (B) representative staining of GluA1 within the dentate gyrus of the hippocampus in the P18 (n = 4), P20 (n = 3), P22 (n = 3), P24 (n = 4), P26 (n = 4), P30 (n = 4), and P50 (n = 4) age groups. (*) indicates significant difference between P18 and P24 (p < 0.05). (!) indicates significant difference between the P50 group and all other age groups (p < 0.05). Data are presented as mean + SEM.