Pubertal activation of estrogen receptor α in the medial amygdala is essential for the full expression of male social behavior in mice.
Testosterone plays a central role in the facilitation of male-type social behaviors, such as sexual and aggressive behaviors, and the development of their neural bases in male mice. The action of testosterone via estrogen receptor (ER) α, after being aromatized to estradiol, has been suggested to be crucial for the full expression of these behaviors. We previously reported that silencing of ERα in adult male mice with the use of a virally mediated RNAi method in the medial preoptic area (MPOA) greatly reduced sexual behaviors without affecting aggressive behaviors whereas that in the medial amygdala (MeA) had no effect on either behavior. It is well accepted that testosterone stimulation during the pubertal period is necessary for the full expression of male-type social behaviors. However, it is still not known whether, and in which brain region, ERα is involved in this developmental effect of testosterone. In this study, we knocked down ERα in the MeA or MPOA in gonadally intact male mice at the age of 21 d and examined its effects on the sexual and aggressive behaviors later in adulthood. We found that the prepubertal knockdown of ERα in the MeA reduced both sexual and aggressive behaviors whereas that in the MPOA reduced only sexual, but not aggressive, behavior. Furthermore, the number of MeA neurons was reduced by prepubertal knockdown of ERα. These results indicate that ERα activation in the MeA during the pubertal period is crucial for male mice to fully express their male-type social behaviors in adulthood.
Laboratory of Behavioral Neuroendocrinology, University of Tsukuba, Tsukuba 305-8577, Japan;
Kazuhiro
K
Sano
Laboratory of Behavioral Neuroendocrinology, University of Tsukuba, Tsukuba 305-8577, Japan;
Mariko
M
Nakata
Laboratory of Molecular Neurosurgery, Weill Cornell University Medical College, New York, NY 10021;
Sergei
S
Musatov
Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan;
Masahiro
M
Morishita
Department of Psychology, Kyoto Tachibana University, Kyoto 607-8175, Japan.
Toshiro
T
Sakamoto
Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan;
Shinji
S
Tsukahara
Laboratory of Behavioral Neuroendocrinology, University of Tsukuba, Tsukuba 305-8577, Japan; ogawa@kansei.tsukuba.ac.jp.
Sonoko
S
Ogawa
D000818:Animals; D066276:Corticomedial Nuclear Complex / Q000378:metabolism*; D047628:Estrogen Receptor alpha / Q000378:metabolism*; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D008813:Mice, Inbred ICR; D011301:Preoptic Area / Q000378:metabolism*; D034622:RNA Interference; D012741:Sexual Maturation; D012919:Social Behavior
D047628:Estrogen Receptor alpha
estrogen receptor α; medial amygdala; pubertal period; social behavioral network; testosterone