Sex-specific expression of estrogen receptors α and β and Kiss1 in the postnatal rat amygdala
Article first published online: 6 DEC 2012
Copyright © 2012 Wiley Periodicals, Inc.
Journal of Comparative Neurology
Volume 521, Issue 2, pages 465–478, 1 February 2013
How to Cite
Cao, J. and Patisaul, H. B. (2013), Sex-specific expression of estrogen receptors α and β and Kiss1 in the postnatal rat amygdala. J. Comp. Neurol., 521: 465–478. doi: 10.1002/cne.23185
- Issue published online: 6 DEC 2012
- Article first published online: 6 DEC 2012
- Accepted manuscript online: 13 JUL 2012 01:54AM EST
- Manuscript Accepted: 6 JUL 2012
- Manuscript Revised: 16 MAY 2012
- Manuscript Received: 2 APR 2012
- National Institute of Environmental Health Sciences (NIEHS). Grant Number: RO1 ES016001
- sexually dimorphic;
The rodent amygdaloid complex is composed of numerous subnuclei important for the sex-specific regulation of sociosexual behavior. Although estrogen receptors (ERs) are critical for organizing functional and cytoarchitectural sex differences in these subnuclei, a detailed developmental profile of ER expression in the amygdaloid complex is not available. Moreover, the kisspeptin gene (Kiss1) was recently identified in the adult amygdala, but it remains unknown if it is expressed during development. To fill these data gaps, rat brains (5–7/group) were assessed on postnatal days (PNDs) 0, 2, 4, 7, and 19 for ER alpha (ERα; Esr1), beta (ERβ; Esr2), and Kiss1 expression using in situ hybridization. Expression was quantified in the posterodorsal portion of the medial amygdala posterodorsal (MePD), lateral (PLCo), and medial (PMCo) components of the posterior cortical nucleus, and the amygdalohippocampal area (AHi). ERα expression was high throughout the amygdala at birth, but sexually dimorphic only in the AHi. ERα expression in the MePD and the PLCo showed a U-shaped expression pattern over time. In the PMCo, ERα expression decreased from PND 2 and remained low through PND 19. Sexually dimorphic expression of ERβ in the MePD was observed on PND 0, with higher levels in females, but reversed by PND 4 due to declining levels in females. No Kiss1 signal was observed in the postnatal amygdala, suggesting that expression arises after puberty. These data reveal that ER expression is region-specific within the neonatal amygdala. These differences likely contribute to sex differences in sociosexual behavior across the lifespan. J. Comp. Neurol. 521:465–478, 2013. © 2012 Wiley Periodicals, Inc.