Fig. 7.

Expression of sex steroid receptors in Rfrp neurons by double-label ISH. A, Representative photomicrographs of double-label ISH of Rfrp (red fluorescence) and ERα (silver grains) in a diestrous female. Rfrp neurons coexpressing ERα (blue arrowhead) and Rfrp neurons with no coexpression of ERα (yellow arrows). 3V, Third ventricle. B, Low-power magnification photomicrograph of extensive ERα expression (silver grains) in the arcuate nucleus, with red Rfrp neurons labeled in the DMN (same animal as panel A). C, Quantification of the percent coexpression of ERα in Rfrp neurons between gonadally intact females (F) and males (M), as well as in GDX+E₂ F and M. There were no significant differences in coexpression between any of the groups. D, Representative photomicrographs of the lack of AR expression in Rfrp neurons. E, Significant AR expression in the hypothalamic ventromedial nucleus of a male mouse from the same assay. F, Quantification of the percent coexpression of AR in Rfrp neurons between F and M.