Fig. 1. Characterization of mammary glands of virgin and pregnant Dgat1^–/– mice. (A) Immunohistochemistry of mammary glands from 8-week-old virgin female Dgat1^+/+ and Dgat1^–/– mice. After fixation, mammary tissue was embedded in paraffin, sectioned, and stained with antibodies specific for the ductal cell marker NKCC1 (red) and smooth muscle actin (SMA, green). (B) Weights of inguinal mammary glands from wild-type and Dgat1^–/– mice during pregnancy.