Estrogen regulates the expression of N-methyl-d-aspartate (NMDA) receptor subunit epsilon 4 (Grin2d), that is essential for the normal sexual behavior in female mice

Estrogen plays important roles in the reproductive behavior of animals. In the present study, we found that the Grin2d gene of mouse possessed half-sites of the estrogen-responsive element (ERE) in the 3′-untranslated region (UTR). Quantitative PCR analysis showed that the reduced Grin2d mRNA expression in the hypothalamus of the ovariectomized mice was restored by estrogen administration. Downregulation of Grin2d mRNA expression was also detected in the hypothalamus of estrogen receptor alpha-knockout female mice. Moreover, estrogen-induced lordosis response was decreased in Grin2d-knockout mice. These results suggest that estrogen regulates lordosis behavior through the regulation of Grin2d expression in the hypothalamus of female mice.