XVI ANNUAL MEETING OF THE ARGENTINE SOCIETY OF BIOLOGY  

出　　处：《BIOCELL》2015年第S01期244-287,共44页生物细胞（英文）

摘　　要：LECTURES A1 UPDATE OF KEY MOLECULES IN THE BRAIN INVOLVED IN THE CONTROL OF PUBERTY AND REPRODUCTION.Kauffman A Department of Reproductive Medicine,UCSD,La Jolla,CA,[e-mail] The neuroendocrine reproductive axis is controlled by various hormonal and neural pathways that converge upon and regulate forebrain gonadotropin-releasing hormone(GnRH)neurons.The status of the reproductive axis and GnRH secretion differs between various life stages,including puberty and adulthood.However,until recently,many of the key neural circuits underlying the control of GnRH neurons at different life stages were only poorly understood.The recently-identified neuropeptides kisspeptin(encoded by the Kiss1 gene),neurokinin B(NKB;encoded by Tac2),and RFRP-3(GnIH;encoded by Rfrp),have been implicated as important regulators of GnRH neurons in numerous species.In mammals,these reproductive neuronal populations are located in several discrete brain regions,including hypothalamic nuclei and the amygdala.Accumulating evidence indicates that kisspeptin and NKB neurons are potent stimulators of the reproductive axis at different life stages,including puberty and adulthood,whereas RFRP-3 neurons inhibit the reproductive axis.Studies have now begun to examine how these circuits are themselves regulated,both in adulthood and development.Findings from multiple mammalian species and both sexes indicate that Kiss1,NKB,and Rfrp neurons are each regulated by sex steroids(estrogen and testosterone),to differing degrees.Intriguingly,the manner in which sex steroids regulate these neurons(stimulatory or inhibitory)is both gene and region-specific within the brain,a finding which may illuminate the cellular mechanisms of steroid-mediated positive and negative feedback regulation of GnRH secretion.Moreover,certain Kiss1 populations undergo sexual differentiation,a developmental process driven by sex steroids during critical postnatal periods.Thus,compounds the mimic or antagonize sex steroid signaling,such as phytoestrogens,can have notable eff

关 键 词：Kiss1 summarized NEURAL 

分 类 号：R33[医药卫生—人体生理学]