RT Journal Article
SR Electronic
T1 Synaptic Connections of Aromatase Circuits in the Medial Amygdala Are Sex Specific
JF eneuro
JO eNeuro
FD Society for Neuroscience
SP ENEURO.0489-19.2020
DO 10.1523/ENEURO.0489-19.2020
VO 7
IS 3
A1 Addison Billing
A1 Marcelo Henrique Correia
A1 Diane A. Kelly
A1 Geng-Lin Li
A1 Joseph F. Bergan
YR 2020
UL http://www.eneuro.org/content/7/3/ENEURO.0489-19.2020.abstract
AB The brains of male and female mice are shaped by genetics and hormones during development. The enzyme aromatase helps establish sex differences in social behaviors and in the neural circuits that produce these behaviors. The medial amygdala of mice contains a large population of aromatase neurons and is a critical hub in the social behavior network. Moreover, the neural representation of social stimuli in the medial amygdala displays clear sex differences that track developmental changes in social behaviors. Here, we identify a potential anatomic basis for those sex differences. We found that sensory input from the accessory olfactory bulb (AOB) to aromatase neurons is derived nearly exclusively from the anterior AOB, which selectively responds to chemosensory cues from conspecific animals. Through the coordinated use of mouse transgenics and viral-based circuit-tracing strategies, we demonstrate a clear sex difference in the volume of synapses connecting the accessory olfactory bulb to aromatase-expressing neurons in the medial amygdala of male versus female mice. This difference in anatomy likely mediates, at least in part, sex differences in medial amygdala-mediated social behaviors.