Figure 2.

E2 and P increase angiogenesis in the pubertal mammary gland. Pubertal 4-week-old BALB/c mice were OVX, allowed to recover for 3 weeks, and then treated for 5 days with vehicle control (C), E2, P, or E2+P. Blood vessel density was measured, as described in Materials and Methods, by the area occupied by CD31-positive vessels near mammary epithelium. The values represent the mean ± SEM (n = 3 animals per treatment). CD31 staining was greater in E2-, P-, and E2+P-treated mammary glands (*, P < .05) compared with Cs.