Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan.
J Physiol Sci. 2012 Nov;62(6):453-60. doi: 10.1007/s12576-012-0222-y. Epub 2012 Aug 1.
Kisspeptins, encoded by Kiss1 gene, play pivotal roles in the regulation of reproduction. Recently, several studies reported a sex difference in Kiss1 expression in the arcuate nucleus (ARC) during the neonatal period. In this study, we investigated the effect of gonadal steroid manipulation on the sex difference in Kiss1 expression in ARC of rats. At neonatal and prepubertal stages, females had a greater number of Kiss1 neurons than the males. Gonadectomy at those stages resulted in significant increases in the Kiss1 neuron number and the sex differences disappeared. We also confirmed the expression of estrogen receptor α in kisspeptin neurons in neonates. Altogether, our results indicate that ARC Kiss1 expression is negatively regulated by gonadal steroids from early postnatal stages, and that the sex difference in ARC Kiss1 expression is attributed to the difference in circulating gonadal steroid levels. We also found that neonatal estrogenization inhibits Kiss1 expression and impairs negative feedback system.
Kisspeptins 由 Kiss1 基因编码,在生殖调控中发挥着关键作用。最近,有几项研究报道了在新生儿期弓状核(ARC)中 Kiss1 表达存在性别差异。在这项研究中,我们研究了性腺类固醇处理对大鼠 ARC 中 Kiss1 表达性别差异的影响。在新生儿期和青春期前阶段,女性的 Kiss1 神经元数量多于男性。在这些阶段进行性腺切除术会导致 Kiss1 神经元数量显著增加,性别差异消失。我们还在新生儿中证实了雌激素受体 α 在 kisspeptin 神经元中的表达。总之,我们的研究结果表明,ARC Kiss1 表达受出生后早期性腺类固醇的负向调节,ARC Kiss1 表达的性别差异归因于循环性腺类固醇水平的差异。我们还发现,新生儿期雌激素化抑制 Kiss1 表达并损害负反馈系统。