Marraudino Marilena, Martini Mariangela, Trova Sara, Farinetti Alice, Ponti Giovanna, Gotti Stefano, Panzica GianCarlo
Neuroscience Institute Cavalieri Ottolenghi (NICO), Regione Gonzole 10, Orbassano, Torino, Italy; Laboratory of Neuroendocrinology, Department of Neuroscience, Rita Levi Montalcini, University of Torino, Via Cherasco 15, Torino, Italy.
Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695-7614, United States.
Brain Res. 2018 Jun 1;1688:8-14. doi: 10.1016/j.brainres.2018.03.014. Epub 2018 Mar 16.
The kisspeptin system is clustered in two main groups of cell bodies (the periventricular region, RP3V and the arcuate nucleus, ARC) that send fibers mainly to the GnRH neurons and in a few other locations, including the paraventricular nucleus, PVN. In physiological conditions, gonadal hormones modulate the kisspeptin system with expression changes according to different phases of the estrous cycle: the highest being in estrus phase in RP3V and PVN (positive feedback), and in ARC during the diestrus phase (negative feedback). In this work we wanted to study these hormonal fluctuations during the estrous cycle, investigating the role played by progesterone (P) or estradiol (E), alone or together, on the kisspeptin system. Gonadectomized CD1 female mice were treated with P, E or both (E + P), following a timing of administration that emulates the different phases of estrous cycle, for two cycles of 4 days. As expected, the two cell groups were differentially affected by E; the RP3V group was positively influenced by E (alone or with the P), whereas in the ARC the administration of E did not affect the system. However P (alone) induced a rise in the kisspeptin immunoreactivity. All the treatments significantly affected the kisspeptin innervation of the PVN, with regional differences, suggesting that these fibers arrive from both RP3V and ARC nuclei.
kisspeptin系统主要集中在两组细胞体（室周区域，RP3V和弓状核，ARC）中，这些细胞体发出的纤维主要投射到促性腺激素释放激素（GnRH）神经元以及其他一些部位，包括室旁核（PVN）。在生理条件下，性腺激素根据发情周期的不同阶段通过表达变化来调节kisspeptin系统：在发情期，RP3V和PVN中的表达最高（正反馈），而在动情后期，ARC中的表达最高（负反馈）。在这项研究中，我们想研究发情周期中的这些激素波动，探究单独或联合使用孕酮（P）或雌二醇（E）对kisspeptin系统的作用。对去卵巢的CD1雌性小鼠按照模拟发情周期不同阶段的给药时间，用P、E或两者联合（E+P）进行处理，为期两个4天的周期。正如预期的那样，这两组细胞受E的影响不同；RP3V组受到E（单独或与P联合）的正向影响，而在ARC中，E的给药对该系统没有影响。然而，单独使用P会导致kisspeptin免疫反应性升高。所有处理均显著影响PVN的kisspeptin神经支配，且存在区域差异，这表明这些纤维来自RP3V和ARC核。
