Fig. 5.

Gonadotropin treatment up-regulates EGR-1 immunoreactivity in the ventral striatum and APOA. (A–F) Photomicrographs in the horizontal plane of Egr-1 immunoreactive cells in the ventral striatum with (A, C, and E) or without (B, D, and F) hCG treatment at low (×10, A and B) or high (×20, C–F) magnifications. In either normal physiological saline (C and D) or Ca²⁺ free/6 mM MgCl²⁺ saline (A, B, E, and F), the number of EGR-1 immunoreactive cells is higher after hCG treatment (black bars, mean ± SEM) compared with saline alone (white bars, mean ± SEM) in the ventral striatum (G) and APOA (H), but not medial pallium (I). ∗, P < 0.05; and ∗∗, P < 0.01 (two-tailed).