Development of genotoxin-exposed glands during pregnancy.

<p>(A, B) <i>Analysis of lobulo-alveolar development during pregnancy.</i> Whole mount preparations from timed pregnant mice (6d p.c, 10 week old mice), exposed as juveniles to DMBA (or not). To examine the pattern of growth in more detail, paraffin sections from mammary glands were immunostained with Ki67 (to show cells in cycle; green) and counterstained with a luminal cell-specific stain, CK8 (K8; red; scale bar = 25 µm). Quantitation of the Ki67 index showed no significant difference between genotoxin-exposed mice and the control cohort. (C) <i>Lobulo-alveolar development during pregnancy in Lrp5−/− glands.</i> Samples were processed according to (B), and were similarly stained with Ki67 and CK8, and also with CK5 (K5; blue) to visualize basal epithelial cells.