Circadian System of Diurnal Rodents: Integrated Physiological/Behavioral Approach

昼夜啮齿动物的昼夜节律系统：综合生理/行为方法

• 批准号: 9118467
• 负责人: Patricia DeCoursey
• 金额: $ 20.98万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-02-01 至 1996-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9118467&HistoricalAwards=false
• 关键词: Circadian; System; Diurnal; Rodents; Integrated

Daily biological timekeeping, best reflected in the perception of lay persons in terms of human "jet-lag" or shift-work maladies, is regulated by a composite interaction of neural pacemaker (SCN) and environmental synchronizing agents. The pacemaker autonomously drives dependent biochemical, physiological and behavioral functions with free-running circadian period under constant environmental conditions close to but not exactly 24-hours, while the environmental entraining or synchronizing agent corrects phase and frequency of the pacemaker to local time. Much mammalian circadian research, particularly the physiological aspect, has been limited to laboratory rats and golden hamsters. In an attempt to distinguish differences between the circadian "wiring" of diurnal mammals and better known nocturnal mammals, the study will examine selected key issues for three diurnal species in successive stages of circadian function including sensory input from the environment for entertainment, physiological properties of the SCN rhythm generator, and behavioral output. Physiological and behavioral circadian output measurements will be employed in these three diurnal rodents to clarify circadian regulation in day-active mammals. The antelope ground squirrel, 13- lined ground squirrel, and eastern chipmunk were chosen as model species to minimize operational problems that have long hindered progress of research on circadian behavioral function in diurnal mammals, and also to assess circadian variation span in ecologically widely divergent desert, prairie, and forest species. Issues will include the light-sampling process for entrainment in lab and field, the role of environmental temperature as well as cyclic body temperature in circadian function, and the delineation of a "light-mimicking" phase response curve system (PRC) by use of intraventricular injection of carbachol; the distribution of key SCN neuropepetides (NP-II, VIP, SS, NPY) will be determined by immunocytochemical methods plus computerized image processing for quantitative determination of co-localized immunoreactivity. Finally, in vitro and in vivo recording of SCN rhythmic output relative to other brain areas will also be investigated. The data may serve as a useful model for better understanding the functioning of diurnal circadian systems of mammals, and more generally for envisioning the means by which the relatively simple neuronal circuitry of the SCN is able to control contrasting nocturnal and diurnal circadian behavior modes.

日常生物计时是由神经起搏器（SCN）和环境同步剂的复合相互作用调节的，最能反映在外行人对人类“时差”或轮班工作疾病的感知上。在接近但不完全是24小时的恒定环境条件下，起搏器自主驱动依赖的生物化学、生理和行为功能，同时环境诱导或同步剂将起搏器的相位和频率校正为当地时间。许多哺乳动物的昼夜节律研究，特别是生理方面的研究，一直局限于实验室大鼠和金仓鼠。为了区分昼行性哺乳动物的昼夜节律“线路”与我们熟知的夜行性哺乳动物之间的差异，该研究将研究三个昼行性哺乳动物在昼夜节律功能的连续阶段中选择的关键问题，包括来自娱乐环境的感觉输入、SCN节律产生器的生理特性、以及行为输出。生理和行为昼夜节律输出测量将用于这三种昼夜活动的啮齿动物，以阐明白天活动的哺乳动物的昼夜节律调节。选择羚羊地松鼠、13线地松鼠和东部花栗鼠作为模式物种，以减少长期阻碍昼夜活动哺乳动物昼夜行为功能研究进展的操作问题，并评估生态上广泛分布的沙漠、草原和森林物种的昼夜变化跨度。问题将包括实验室和野外夹带的光采样过程，环境温度和循环体温在昼夜节律功能中的作用，以及通过使用脑室内注射甲醇来描绘“光模拟”相响应曲线系统（PRC）；关键SCN神经肽（NP-II， VIP， SS， NPY）的分布将通过免疫细胞化学方法和计算机图像处理来定量测定共定位免疫反应性。最后，在体外和体内记录与其他脑区相关的SCN节律输出也将被研究。这些数据可以作为一个有用的模型，更好地理解哺乳动物昼夜节律系统的功能，更广泛地说，用于设想SCN相对简单的神经元回路能够控制夜间和白天昼夜节律行为模式的方法。