Figure 3: Multilocular brown adipose appearance in Brca1 mutant mice shows increased staining for CD31, a marker of angiogenesis. Immunohistochemical detection of the angiogenesis marker, CD31 in the mammary fat pad of wildtype (a) and Brca1f/f;MMTV-Cre (b) postpubertal mice (6 months of age). Magnification, x 40. Arrowheads point to areas with CD31 positive staining.