(A) Expression of Kiss1 and Kiss1r in mammary glands injected with lentiviral shRNA for scr (control), Kiss1 or Kiss1r, showing down-regulation of Kiss1 and Kiss1r in mammary glands. (B) Immunohistochemistry staining for breast tissues infected with lentivial shRNA for scr, Kiss1 or Kiss1r. (C) Hyperplastic nodule numbers in mammary glands infected with different shRNAs for control, Kiss1 and Kiss1r, respectively. The representative images were shown in the top of the figure.