Immunohistochemistry of TGF-β1, TGF-β2 and TGF-β3 in rat endometrium during the estrous cycle. IHC shown are from one representative experiment and were repeated four times using four different uterine sections from four different rats per day of the estrous cycle. Representative days of estrous cycle are presented (diestrus; proestrus; estrus; metestrus). C-: negative control. LE: luminal epithelium; S: stroma. Magnification: 400×.