下丘脑MnPO核团神经元的化学表型和投射目标及其与睡眠和体温调控功能关系的系统研究

The hypothalamic MnPO nucleus plays important roles in the regulation of physiological functions such as body temperature, sleep and electrolyte homeostasis. The role of MnPO in body temperature and sleep regulation has been the focus of studies during recent years. However, a systematic study on the diversity of MnPO neurons' chemical phenotypes and their projection targets, in relation to their activation states during distinct physiological states, is still lacking. In this project, we are going to inject retrograde tracers to the MnPO projection targets （including the hypothalamic VLPO,PVH,DMH and LH nuclei; DR, vlPAG and RPa in the brainstem）in rats to label MnPO neurons. In combination with immunohistochemistry and in situ hybridization for tracer labeling and neurotransmitter identification, together with c-Fos mapping of neuronal activation states during body sleep and/or body temperature recording, we plan to systematically investigate the relationships between MnPO neurons' chemical phenotypes, their projection targets, and their functional states under various conditions, and to provdie a basis for future studies on the effects of MnPO lesion on sleep and body temperature regulation. Results from this study will help to gain deeper understanding on the roles of MnPO in the regulations of sleep and body temperature and their commonality from the systems neuroscience point of view. The results will also help to illucidate the mechanisms of the sleep regulation under normal and pathological conditions.

下丘脑的MnPO核团参与调控体温，睡眠及体液渗透压等多种重要生理活动参数，其中MnPO对体温和睡眠的调控是近年来研究的热点，但目前尚缺乏对MnPO神经元化学表型，投射目标及其在不同生理活动状态下的功能状态的系统研究。本项目将采用大鼠为实验动物，利用神经元逆向示踪技术标记投射到特异下游目标（包括下丘脑内的VLPO，PVH，DMH和LH核团；脑干的DR，vlPAG和RPa核团等）的MnPO神经元。结合免疫组化及原位杂交等分析手段和对神经元激活状态的c-Fos表达分析，以及对动物睡眠和体温活动的监测，系统阐明MnPO神经元所表达的神经递质、所控制的下游神经结构及其在不同生理功能中的激活状态间的关系，并为后续的MnPO损毁对睡眠和体温调控影响的实验提供基础。项目成果将有助于深入理解MnPO参与睡眠和体温调节的机制以及睡眠和体温调节共性的系统神经生物学基础，并有助于睡眠相关疾病机理的阐释。

通过该项目的资助项目组已经培养了一名硕士研究生毕业。项目在执行过程中遇到关键设备和学生缺乏等关键问题无法得到妥善解决，相关问题在前期的进展报告中已经对此向基金委详细进行说明。在本项目的资助下，项目组也从事了很多其它的研究工作，如进行了VIP-Cre和AVP-cre小鼠的构建和生物节律研究工作，并进行了生物钟对肝脏线粒体功能的调控及其随衰老而发生改变的相关研究，取得了很好的研究成果，相关的研究论文发表在Chronobiology International杂志上。项目组还在项目资助期间进行了较大规模的高通量测序研究工作，详细分析了小鼠肝脏基因表达节律的转录调控基础。