Real-time Monitoring of Neurotransmitters in a Hypoxic Environment

描述(由申请人提供)：缺血性脑损伤的病因仍然难以捉摸。过去，对缺氧和缺血损伤机制的研究(S)面临三大限制。首先，很难用足够的灵敏度和时间分辨率来测量一些假定的病因。要么传感器不存在，要么它们 在低氧环境中，活组织不能很好地发挥作用。其次，实验条件并没有有效地模拟脑缺血。最后，对完整动物缺氧影响的研究往往局限于对损伤后行为和组织损伤解剖程度的分析，而不是关注损伤和修复介质在实际缺血损伤过程中的活动。因此，减少制剂(如谷氨酸、乳酸)中的损伤介质在完整动物身上还没有得到广泛的研究。针对这些局限性，我们有以下几个目标：1.基于金属氧化物技术开发和表征新型谷氨酸和乳酸电化学生物传感器，使其在低氧环境下工作。2：在完整动物大脑中动脉闭塞缺血性脑损伤模型中测试生物传感器，以确定乳酸和谷氨酸变化的时间分布。新的酶传感器设计将扩大可用于体内谷氨酸和乳酸测量的电化学探针库，并为研究这些神经递质在低氧条件下的神经生物学提供新的方法。这项研究将有助于研究和进一步了解谷氨酸和乳酸在各种神经疾病中的神经传递，在这些疾病中，氧气是一个限制性因素。 与公共健康相关：该项目将开发、优化并将一种新的传感技术转化为临床实践，用于体内监测与缺氧期间的神经信号和功能相关的关键分析物(谷氨酸和乳酸)。这项技术将实时评估完好清醒动物体内这些神经因素的变化，并对与体内缺氧条件下涉及的生化和细胞事件有关的基本问题提供机械性答案。这些研究很重要，而且与人类健康相关，因为许多疾病的组织氧水平不同，而乳酸和谷氨酸等损伤介质在低氧条件下的作用尚不清楚。

DESCRIPTION (provided by applicant): The etiology of ischemic brain injury remains elusive. Studies of the mechanism(s) of injury during hypoxia and ischemia have faced three major limitations in the past. First, it has been difficult to measure some of the putative etiological factors with adequate sensitivity and temporal resolution. Either the sensors do not exist or they do not function well in the hypoxic environment in live tissue. Second, the experimental conditions have not mimicked brain ischemia effectively. Finally, studies of the effects of hypoxia in intact animals have often been limited to analyses of behavior and the anatomical extent of tissue damage after the injury rather than focusing on the activity of mediators of injur and repair as they evolve during the actual ischemic insult. As a result, the mediators of injury in reduced preparations (e.g., glutamate, lactate) have not been studied extensively in intact animals. To address these limitations, we have the following aims: 1: Develop and characterize novel electrochemical biosensors for glutamate and lactate based on metal oxide technology so that they work in a low oxygen environment. 2: Test the biosensors in the middle cerebral artery occlusion model of ischemic brain injury in intact animals to determine the temporal profile of changes in lactate and glutamate. The new enzyme sensor design will expand the arsenal of accessible electrochemical probes for in vivo measurement of glutamate and lactate, and provide new methods for studying the neurobiology of these neurotransmitters in hypoxic conditions. This research will facilitate study and further fundamental understanding of glutamate and lactate neurotransmission in a variety of neurological disorders in which oxygen is a restrictive factor. PUBLIC HEALTH RELEVANCE: This project will develop, optimize and translate into clinical practice a novel sensing technology for in vivo monitoring of key analytes associated with neural signaling and function during hypoxia (glutamate and lactate). This technology will provide real-time assessment of the changes in these neurological factors in intact awake animals and provide mechanistic answers to fundamental questions related to the biochemical and cellular events involved in vivo in conditions of oxygen deprivation. These studies are important and have relevance for human health because tissue oxygen levels vary in many diseases, and the role of the mediators of injury like lactate and glutamate in hypoxic conditions is not well understood.