Estradiol level and total AKT expression in wild-type (WT) and transgenic mice. (A) Blood samples were collected from virgin, lactating, and post-lactating mice and serum estradiol levels were measured by ELISA assay according to the manufacturer’s instructions. The line graph indicates trend of estradiol levels (mean of seven samples plus SD) in WT (n = 21) and transgenic mice (n = 21) from virgin to post-lactating stage. (B) RNA was collected from the mammary glands of WT and transgenic mice and RT-PCR was performed with AKT primers and quantified with β-actin. The lines indicate the trends of mean levels of total AKT adjusted for β-actin in the mammary glands of WT (n = 9) and transgenic mice (n = 9) at pre-puberty virgin (5 weeks olde, n = 3), puberty virgin (9 weeks olde, n = 3), lactating (14 weeks old, n = 3) and post-lactating (16 weeks old, n = 3) stages. (C) mRNA levels of total AKT from different organs in WT (top) and transgenic mice (bottom) at indicated stages were determined by RT-PCR. The mean total AKT levels are adjusted for β-actin was shown in the bar graphs. Each bar indicates mean and SD from four mice. Each sample was triplicated and “*” indicates p < 0.05 compared to virgin.