GnRHR-TAg transgenic mice express SV40 TAg at 2 months of age (2M), and their pituitary LHβ and FSHβ levels are reduced earlier and to a greater extent in females than males. Representative images of immunohistochemistry of anterior pituitary serial sections immunostained for SV40 TAg, LHβ, and FSHβ from female (A) and male (B) mice at 2 or 5 months of age (5M). Magnification, ×100. Bars, 100 μm.