Neuroendocrine Determinants of Mating in The Day Versus Night

白天与夜间交配的神经内分泌决定因素

• 批准号: 0130977
• 负责人: Laura Smale
• 金额: $ 35.74万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-04-15 至 2006-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0130977&HistoricalAwards=false
• 关键词: Neuroendocrine; Determinants; Mating; Day; Versus

Animals have internal biological clocks that enable them to coordinate physiological and behavioral rhythms relative to the time of day, termed circadian rhythms. In mammals, a key part of clock in the brain is the supra-chiasmatic nucleus (SCN) of the hypothalamus. In nocturnal rodents, which are widely used in the laboratory, the SCN is known to be important for the timing of female reproductive behavior and a surge in the luteinizing hormone (LH) that triggers ovulation. However very little is known about diurnal rodents, which have evolved from nocturnal species. This project asks how the neural mechanisms responsible for circadian control of the female reproductive cycle have changed in diurnal compared to nocturnal rodents. The model animal is the unstriped Nile grass rat, which is related to common laboratory rats, but has a virtually complete reversal in the timing of a variety of events associated with female reproduction, including morning instead of evening timing for both mating behavior and for the surge in LH. Cytochemical, anatomical and behavioral approaches will be used to distinguish whether the SCN itself changes signal timing, whether there is instead a change in the timing of receptiveness of target sites to SCN signals, or whether there is a change in the neuroanatomy connecting SCN to different targets in nocturnal and diurnal species. The results will have an impact beyond neuroendocrinology to chronobiology, hypothalamic physiology, and evolutionary physiology. In addition, training of students and researchers at several levels is an important part of the project.

动物有内部生物钟，使他们能够协调生理和行为节奏相对于一天的时间，称为昼夜节律。 在哺乳动物中，大脑中时钟的关键部分是下丘脑的视交叉上核（SCN）。 在实验室中广泛使用的夜间啮齿动物中，已知SCN对于女性生殖行为的时间和触发排卵的促黄体生成激素（LH）的激增是重要的。 然而，人们对从夜行性物种进化而来的昼行性啮齿动物知之甚少。 该项目询问了与夜间啮齿动物相比，负责女性生殖周期昼夜节律控制的神经机制如何在白天发生变化。 模型动物是无条纹的尼罗河草鼠，它与普通实验室大鼠有关，但与雌性生殖相关的各种事件的时间几乎完全逆转，包括交配行为和LH激增的早晨而不是晚上。 细胞化学、解剖学和行为学方法将用于区分SCN本身是否改变信号定时，靶位点对SCN信号的接受性定时是否发生变化，或者将SCN连接到夜间和昼夜物种中的不同靶点的神经解剖学是否发生变化。 这些结果将对神经内分泌学、时间生物学、下丘脑生理学和进化生理学产生深远的影响。 此外，对学生和研究人员进行各级培训也是该项目的一个重要组成部分。