title: Sex differences of excitatory synaptic transmission in RA projection neurons of adult zebra finches.
abstract: Zebra finches are ideal animals to investigate sex difference in songbirds. Only males can sing. The brain nuclei controlling song learning and production in males are considerably larger than in females. The robust nucleus of the arcopallium (RA) is a premotor nucleus, playing a key role in controlling singing. RA receives denser synapse inputs in males than in females. Sex differences of excitatory synaptic transmission in the RA projection neurons (PNs) have not been reported. In the present study, using whole-cell voltage-clamp recording, spontaneous EPSCs (sEPSCs) and miniature EPSCs (mEPSCs) of RA PNs in the intact males and females were recorded. The average frequency and amplitude of sEPSCs/mEPSCs in the intact males were higher than females. The half-width and decay time of sEPSCs/mEPSCs in the intact males were longer than females. In order to verify whether these sex differences related to sex steroids, males were castrated. The average frequency of sEPSCs/mEPSCs in castrated males was lower than intact males and was similar to in females; the amplitude was not changed after castrating. These results demonstrate the sexually dimorphic of the excitatory synaptic transmission in the RA PNs, the RA PNs in males receive more excitatory synaptic transmission and these sex differences were partly affected by sex hormones. These findings contribute to further illuminate the neural mechanisms under the sexually dimorphism in song production of adult zebra finches.
authors.affiliation: School of Life Science, South China Normal University, Key Laboratory of Ecology and Environmental Science in Higher Education of Guangdong Province, Guangzhou 510631, China.
authors.forename: Songhua
authors.initials: S
authors.lastname: Wang
authors.affiliation: School of Life Science, South China Normal University, Key Laboratory of Ecology and Environmental Science in Higher Education of Guangdong Province, Guangzhou 510631, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Meng
authors.affiliation: School of Life Science, South China Normal University, Key Laboratory of Ecology and Environmental Science in Higher Education of Guangdong Province, Guangzhou 510631, China.
authors.forename: Shaoyi
authors.initials: S
authors.lastname: Liu
authors.affiliation: School of Life Science, South China Normal University, Key Laboratory of Ecology and Environmental Science in Higher Education of Guangdong Province, Guangzhou 510631, China.
authors.forename: Congshu
authors.initials: C
authors.lastname: Liao
authors.affiliation: School of Life Science, South China Normal University, Key Laboratory of Ecology and Environmental Science in Higher Education of Guangdong Province, Guangzhou 510631, China.
authors.forename: Qingyao
authors.initials: Q
authors.lastname: Huang
authors.affiliation: School of Life Science, South China Normal University, Key Laboratory of Ecology and Environmental Science in Higher Education of Guangdong Province, Guangzhou 510631, China. Electronic address: dfliswx@126.com.
authors.forename: Dongfeng
authors.initials: D
authors.lastname: Li
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology*; D002369:Castration; D019706:Excitatory Postsynaptic Potentials; D005260:Female; D046369:Finches / Q000502:physiology*; D008297:Male; D055369:Miniature Postsynaptic Potentials; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques; D012727:Sex Characteristics; D009435:Synaptic Transmission; D014828:Vocalization, Animal
keywords: Projection neurons; Sex differences; The robust nucleus of the arcopallium; sEPSCs/mEPSCs