Sleep and circadian rhythms monitoring systems for mice

睡眠对于高等生物体的生命来说是必不可少的。根据目前的模型，睡眠是由两种机制编排的：昼夜节律和体内平衡过程。在哺乳动物中，昼夜节律过程起源于大脑中的主要生物钟，并在生理功能(体温、警觉性)中产生大约24小时的节律。动态平衡过程是一种沙漏机制，它根据先前清醒的时间和质量来调节睡眠强度。它的性质还没有明确定义，过程相互作用的方式也是未知的。然而，最近的研究支持突触参与睡眠调节，突触是神经细胞之间沟通的功能单位。突触黏附分子将突触的两侧连接在一起，但更重要的是，这些蛋白质控制着神经元之间的交流强度。在这个项目中，将调查黏附系统对睡眠调节的贡献。首先，将通过剥夺小鼠的睡眠来评估动态平衡过程的标记物(即大脑电活动和基因表达)，其中特定突触分子通过RNA干扰下调。要做到这一点，需要获得一个睡眠监测系统，用于同时记录8只老鼠。其次，将使用温度和活动记录来评估昼夜节律系统的特性(例如，内源性周期的长度和对光刺激的相移反应)，在小鼠中，突触分子也通过RNA干扰下调。这一目标将通过获取一个遥测系统来实现，该系统用于连续记录老鼠的温度和活动。该项目的成果将促进我们对睡眠生理和神经功能的了解，并有助于开发治疗和干预涉及睡眠调节过程障碍的患者，包括与年龄相关的变化和失眠。因此，需要资金购买进行研究所需的睡眠和遥测监测系统。

Sleep is essential to life in higher organisms. According to current models, sleep is orchestrated by two mechanisms: circadian and homeostatic processes. In mammals, the circadian process originates from the main biological clock in the brain and generates an about 24-h rhythm in physiological functions (body temperature, alertness). The homeostatic process is an hourglass mechanism that regulates sleep intensity according to the duration and quality of prior wakefulness. Its nature has not been clearly defined and the way the processes interact is also unknown. However, recent work supports the involvement of synapses, the functional unit of communication between neuronal cells, in sleep regulation. Synaptic adhesion molecules hold the two sides of the synapse together but, more importantly, these proteins control the strength of the communication between neurons. In this project, the contribution of adhesion systems to sleep regulation will be investigated. First, the markers of the homeostatic process (i.e. brain electrical activity and gene expression) will be evaluated using sleep deprivation in mice where specific synaptic molecules are downregulated using RNA interference. To do so, the acquisition of a sleep monitoring system for simultaneous recording of 8 mice is required. Second, the properties of the circadian timing system (e.g. the length of the endogenous period and the phase-shift response to light stimulus) will be evaluated using temperature and activity recording in mice in which synaptic molecules are downregulated using RNA interference as well. This aim will be accomplish via the acquisition of a telemetry system for continuous recording of temperature and activity in mice. The results of the project will advance our understanding of sleep physiology and neuronal functions, and assist in the development of treatments and interventions for patients suffering from disorders involving disturbance in sleep regulatory processes, including age-related changes and insomnia. Accordingly, funds are requested for the purchase of the required sleep and telemetry monitoring systems to perform the research.