Figure 1

Representative photomicrographs of apoptotic cells labeled by TUNEL staining in AVPV of 150 day-old male Long-Evans rats fed either an isoflavone-free diet (Phyto-free) or an isoflavone-rich diet (Phyto-600) from conception until time tissue collected. Apoptotic cells were visualized with diaminobenzadine (DAB) and seen as brown nuclear staining. Sections were counterstained with hematoxylin (blue). A and C are representative photomicrographs of the Phyto-free AVPV (n = 5). B and D are representative photomicrographs of the Phyto-600 AVPV (n = 5). Across the diet treatments, A corresponds to a similar coronal brain section in B. The AVPV is outlined with dashed lines. Boxed regions in A and B are magnified and shown in C and D, respectively. Significantly more apoptotic cells (arrows) were observed in Phyto-600 AVPV than the Phyto-free group (n = 5; p < 0.001; two-sample student t-test). Bar = 25 μm for all the photomicrographs.