Annual Rhythms of Energy Balance and Behavior

总体目标是描述下丘脑神经肽Y机制在 控制日常的麻木状态，这是一种极端的温度调节方式，它的进化是为了帮助动物 食物供应有限。整合整体能量的中枢和外周神经机制 平衡和麻木将被探索。食物摄入和体重、生殖和 在西伯利亚仓鼠（Photopus sungorus）中，每天都有很好的记录， 实验具体目的包括：（1）测定和对比下丘脑神经肽， 神经肽mRNA水平，尤其是神经肽Y，在迟钝和非迟钝的Sibedan仓鼠中; 2） 检查用神经肽Y受体拮抗剂预处理是否可以防止自发性 和/或2DG诱导的麻痹; 3）确定连续的NPY输注是否产生延长的 4）评估是否通过阻断去甲肾上腺素受体来抑制产热， 棕色脂肪组织产生类似于冬眠的体温过低。 我们仍然不了解的生理机制的控制下， 能量平衡和体温调节。描述特定神经通路之间的相互作用， 在西伯利亚仓鼠这样的模型系统中，神经递质和日常的麻木可以提供重要的 对哺乳动物，特别是人类这些过程的调节的见解。更好的 了解可逆性体温过低的机制具有医学意义。减少 与体温过低同时发生的新陈代谢、血流等在许多类型的体温过低期间可能是非常有益的。 大手术，尤其是器官移植。目前对这种机制知之甚少， 西伯利亚仓鼠和其他几个物种经历体温过低，这对人类和大多数人来说是致命的。 !其他哺乳动物拟议的研究解决了调控生物学中的基本问题， 因此，提供了建立适用于所有人的一般原则的机会。 哺乳动物

The overall goal is to characterize the role that hypothalamic neuropeptide Y mechanisms play in controlling daily torpor, an extreme form of temperature regulation that evolved to help animals contend with limited food availability. The central and peripheral neural mechanisms integrating overall energy balance and torpor will be explored. Annual rhythms of food intake and body mass, reproduction, and daily torpor are well documented in the Siberian hamster (Phodopus sungorus), the model species in all experiments. Specific aims include: 1) measuring and contrasting hypothalamic neuropeptide and neuropeptide mRNA levels, especially neuropeptide Y, in torpid and non-torpid Sibedan hamsters; 2) examining whether pretreatment with a neuropeptide Y receptor antagonist can prevent spontaneous and/or 2DG-induced torpor; 3) determining whether successive NPY infusions produce prolonged hypothermia; 4) evaluating whether inhibiting thermogenesis by blocking norepinephrine receptors at brown adipose tissue produces torpor-like hypothermia. Much remains that we do not understand about the physiological mechanisms underlying the control of energy balance and thermoregulation. Delineating the interaction between specific neural pathways and neurotransmitters and daily torpor in a model system like the Siberian hamster could provide important insights into the regulation of these processes for mammals in general and humans in particular. A better understanding of the mechanisms of reversible hypothermia is of medical import. The reduced metabolism, blood flow, etc. coincident with hypothermia may be very beneficial during many types of imajor surgery, especially organ transplants. Little is known at this time of the mechanism that allows Siberian hamsters and several other species to undergo hypothermia which is lethal to humans and most !other mammals. The proposed research addresses fundamental questions in regulatory biology and, thereby, affords the opportunity of establishing general principles applicable to all mammals.