A, Dark-field photomicrograph of the DMH showing GnIH(RFRP) mRNA-expressing cells. 3V, Third ventricle. Scale bar, 200 μm. B, Effect of ovariectomy and E replacement on GnIH mRNA expression in the DMH/PVN of nonbreeding and breeding season ewes. Left panel depicts the number of GnIH mRNA-expressing cells per section, and the right panel shows the number of silver grains per GnIH cell (reflecting expression per cell) is shown. Values are means (± sem).