The molecular and cellular basis of cold sensation

描述（由申请人提供）：为了补充目前可用的冷行为测定，我们开发了一种新的高通量行为测定来测量不受限制的小鼠对冷刺激的反应.将小鼠在硼硅酸盐玻璃板上的塑料外壳中驯化，并将后爪正下方的玻璃用干冰颗粒快速冷却，直到小鼠缩回其爪。将从干冰刺激中撤出的潜伏期量化为小鼠对冷作出反应的温度的量度。该试验将用于提供关于TrpM 8-/-、TrpA 1-/-和TrpM 8-TrpA 1双敲除小鼠的冷敏感性的明确信息，并因此提供关于TrpM 8和TrpA 1在冷感觉中的作用的明确信息。 为了更好地理解哪些神经元群体对于这些信号的传递是重要的，我们使用光遗传学技术来暂时沉默外周中的感觉神经元的特定离散群体，而无需任何手术干预或改变神经元结构。使用这种技术，我们沉默特定的神经元群体，同时从我们的新测定中施加冷刺激，使我们能够测试这些群体中的每一个在对冷刺激的反应中的作用。

DESCRIPTION (provided by applicant): To complement the currently available cold behavioral assays, we have developed a novel high- throughput behavioral assay to measure the responses of unrestrained mice to cold stimuli. Mice are acclimated in plastic enclosures on a borosilicate glass plate, and the glass directly underneath the rear hind paw is rapidly cooled with a dry ice pellet until the mouse withdraws its paw. The latency to withdrawal from the dry ice stimulus is quantified as a measure of the temperature at which the mouse responds to cold. This assay will be used to provide unambiguous information about the cold sensitivity of TrpM8-/-, TrpA1-/-, and TrpM8-TrpA1 double knockout mice, and therefore about the roles of TrpM8 and TrpA1 in cold sensation. To better understand which neuronal populations are important for the transmission of these signals, we use optogenetic techniques to transiently silence specific, discrete populations of sensory neurons in the periphery without any surgical intervention or altering the neuronal architecture. Using this technique, we silence specific neuronal populations while applying the cold stimulus from our new assay, allowing us to test the role of each of those populations in the response to the cold stimulus.