Research Article

Pregnancy Promotes Maternal Hippocampal Neurogenesis in Guinea Pigs

Figure 2

Analysis of putative neural precursors with immunolabeling of the zinc finger transcription factor Sp8 in guinea pigs at early gestational, late gestational, postpartal, and postweaning stages relative to nonpregnant females. Midhippocampal images of Sp8 immunolabeling (brown) with hematoxylin counterstain (blue) from individual animal groups are illustrated as indicated. The left panels (a, d, j, and m) are low-magnification images showing the orientation of hippocampal formation, with framed areas enlarged accordingly as the middle (b, r, h, k, and n) and right (c, f, i, l, and o) panels. Sp8+ profiles (pointed by arrows) are nuclear as judged by the size and shape in reference to hematoxylin stain and are overwhelmingly localized to the SGZ (b, c, e, f, h, i, k, l, n, and o). The labeled cells are noticeably denser in the dentate gyrus of the late gestational group (i) than in other groups (c, f, l, and o). (p) illustrates the method for measuring the total length of the GCL. (q) shows the designation of a band area for counting Sp8+ cells along the GCL (the same as noted for Ki67+ cells in Figure 1). (r) plots the numeric densities of Sp8+ cells in the groups. There is a significant difference of the medians in the groups by Kruskal-Wallis test. Post hoc analysis reports significant difference () for late gestational and postpartal groups relative to the control group. Abbreviations are as defined in Figure 1. Scale  μm in (a) applying to (d, g, j, and m), equal to 250 μm for (p), 100 μm for (b, e, h, k, n, and q) and 25 μm for (c, f, i, l, and o).