Hippocampal PCL and GCL volume in rT1, rT2, and rT3 mice. A, Representative photomicrographs of hippocampi (bregma: −2.18 mm) at varied ages of rT1, rT2, rT3, and non-Tg (combining non-Tg littermates of rT1, rT2, and rT3 mice at the same age; for details, see Experimental design and statistical analyses) mice. Scale bars, 300 µm. B, Scatterplots illustrating the volumes of PCLs of the CA1 (left) and CA2-3 (middle), and GCL of the DG (right). Pyr. Vol., PCL volume; Gra. Vol., GCL volume. C, Post hoc comparisons of cell layer volumes at varied ages between mouse lines. p values of <0.05 are highlighted in bold. M, months of age. For detailed gender distribution and numbers of animals used, see Table 1.