Exogenous kisspeptin does not alter photoperiod-induced gonadal regression in Siberian hamsters (Phodopus sungorus)
Exogenous kisspeptin does not alter photoperiod-induced gonadal regression in Siberian hamsters (Phodopus sungorus)
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DOI：
10.1016/j.ygcen.2008.02.017
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发表时间：
2008-05-01
影响因子：
2.7
通讯作者：
Demas, Gregory E.
中科院分区：
文献类型：
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作者：
Greives, Timothy J.;Kriegsfeld, Lance J.;Demas, Gregory E.
为了成功繁殖，动物必须整合多种环境线索，使繁殖与有利条件同步。在温带季节性繁殖的啮齿动物中，光周期是主要的季节性线索。长日照与生殖发育和性腺成熟有关，而短日照则导致性腺退化。神经肽kisspeptin对生殖发育具有强有力的刺激作用。Kisspeptin有效地刺激季节性繁殖动物的GnRH释放和Kisspeptin表达随光周期变化。在这里，我们测试的假设，生殖退化抑制日长的结果减少kisspeptin刺激的生殖轴在季节性繁殖的西伯利亚仓鼠（Photopus sungorus）。如果是真的，在退化的仓鼠中，kisspeptin治疗应该加速性腺再生，在退化之前和期间治疗应该防止仓鼠的性腺再生。在实验1和2中，我们测试了kisspeptin逆转性腺退化的能力。在实验1中，生殖退化仓鼠接受慢性kisspeptin通过渗透微型泵4周。在实验2中，每天注射kisspeptin给退化仓鼠6周。在实验3中，测试了kisspeptin阻断性腺退化的能力;转移到短日的仓鼠每天接受kisspeptin注射，持续6周。在所有三项研究中，接受外源性kisspeptin的短日照动物与短日照对照动物没有差异。总的来说，这些结果提供的证据表明，除了那些收敛于kisspeptin系统的机制可能是关键的季节性变化的生殖轴。(c)2008年爱思唯尔公司All rights reserved.
In order to reproduce successfully, animals must integrate multiple environmental cues to synchronize breeding with favorable conditions. In temperate, seasonally breeding rodents, photoperiod acts as the primary seasonal cue. Long days are associated with reproductive development and maturation of the gonads whereas short days induce gonadal regression. The neuropeptide kisspeptin has potent stimulatory effects on reproductive development. Kisspeptin potently stimulates GnRH release and kisspeptin expression co-varies with photoperiod in seasonally breeding animals. Here we tested the hypothesis that reproductive involution in response to inhibitory day lengths results from reduced kisspeptin stimulation of the reproductive axis in seasonally breeding Siberian hamsters (Phodopus sungorus). If true, gonadal regrowth should be hastened by kisspeptin treatment in regressed hamsters and prevented in hamsters by treatment prior to and during regression. In Experiments 1 and 2 we tested the ability of kisspeptin to reverse gonadal regression. In Experiment 1, reproductively regressed hamsters received chronic kisspeptin via osmotic mini-pumps for 4 weeks. In Experiment 2, daily injections of kisspeptin were administered to regressed hamsters for 6 weeks. In Experiment 3, the ability of kisspeptin to block gonadal regression was tested; hamsters transferred to short days received daily injections of kisspeptin for 6 weeks. In all three studies, short-day animals receiving exogenous kisspeptin did not differ from short-day controls. Collectively, these results provide evidence that mechanisms in addition to those that converge on the kisspeptin system are likely critical for seasonal changes in the reproductive axis. (c) 2008 Elsevier Inc. All rights reserved.