CIRCANNUAL RHYTHMS, BEHAVIOR AND REPRODUCTION

描述(改编自申请者摘要)：本项目旨在 明确每周一次的行为节律的神经内分泌基础 哺乳动物生理学。模范物种是金色的披肩土地 松鼠Spermophilus lateris以前的绝大多数研究都是关于 季节性集中在并非完全内生的节奏上。 (第I类节律)。这个项目涉及的是完全内生的 在没有节律的情况下持续许多周期的周年节律 环境输入(类型II节奏)。产生和产生的机制 同步类型II的节律不同于调节类型I的节律 节奏。第二类节律在长寿哺乳动物中很常见，包括 灵长类动物；也许是洞察 人类行为和生理中II型节律的神经内分泌基础 就是研究相关的动物模型体系。当前的具体目标 项目包括：1)描述视交叉上的作用 核团在控制身体质量、生殖和生殖的昼夜节律 冬眠到每个循环的特定阶段，并确定 一年一次的时钟是否会产生几种节奏，2) 评估长期低温对昼夜节律的影响： 是控制身体质量和生殖节律的时钟(S)吗 在连续冬眠两年或更长时间的松鼠身上被捕？ 3)视交叉上核在性行为中的作用 循环年度组织的差异，4)确定是否发生变化 组织温度的变化是惊人的一年一次 运动活动中昼夜节律的调节，以及5)完成 正在进行的对褪黑激素阶段的神经部位的分析 改变一年一次的节奏。这项研究可能会为深入了解 人类节律的最接近的神经基础和帮助发展 激素和光照疗法治疗季节性情感性精神障碍 紊乱和其他季节性干扰。

DESCRIPTION (Adapted from applicant's abstract): This project seeks to specify the neuroendocrine bases for circannual rhythms in behavior and physiology of mammals. The model species is the golden-mantled ground squirrel Spermophilus lateralis. The great majority of prior studies of seasonality has focused on rhythms that are not completely endogenous (Type I rhythms). This project is concerned with completely endogenous circannual rhythms that persist for many cycles in the absence of environmental input (Type II rhythms). The mechanisms that generate and synchronize Type II rhythms differ from those that mediate Type I rhythms. Type II rhythms are common in long-lived mammals, including primates; perhaps the most accessible route to gaining insight into the neuroendocrine bases of Type II rhythms in human behavior and physiology is to study relevant animal model systems. Specific aims of the present project include: 1) characterization of the role of the suprachiasmatic nucleus in gating circannual rhythms of body mass, reproduction and hibernation to specific phases of each circannual cycle and determining whether a single circannual clock generates the several rhythms, 2) assessment of the effects of prolonged hypothermia on circannual rhythms: are the clock(s) that gate the body mass and reproduction rhythms arrested in squirrels that hibernate continuously for two or more years? 3) determination of the role of the suprachiasmatic nucleus in sex differences in circannual organization, 4) establishing whether changes in tissue temperature are necessary for the striking circannual modulation of circadian rhythms in locomotor activity, and 5) completion of an ongoing analysis of the neural sites at which melatonin phase shifts circannual rhythms. This research may provide insight into the proximate neural bases for human rhythms and aid in the development of hormone and light therapies for treatment of seasonal affective disorders and other seasonal disturbances.