Multifunctional Microprobe for Multiple Neurotransmitter Sensing and Optogenetics

描述(申请人提供)：通过一种方法同时和接近实时地测量大脑中的多个神经活性分子，将极大地促进了解网络中的神经元如何相互作用来控制行为。现有方法要么提供单一分析物的快速测量(例如，快速扫描循环伏安法)，要么提供时间分辨率不足的多个分析物测量(微透析)。在这里，我们将开发一种植入式微探针，能够同时快速监测三种普遍存在的神经递质/神经调节剂：多巴胺(DA)、谷氨酸(GLUT)和乙酰胆碱(ACh)。此外，我们将利用光遗传学的力量，将光波导结合到微探针中，为平行于微电极阵列上每个传感电极的组织提供定向照明。这将使用一种创新的硅基微探针设计来实现，该设计带有嵌入的波导和分光器，并在每个微电极下嵌入一个微镜，以实现均匀的方向光照明。合成的微探针将结合对遗传隔离神经元终端的局部调制和从这些终端释放的递质的测量，以及网络内神经元释放其他递质的结果变化，所有这些都是在自由行为动物的背景下进行的。这些传感器将在广泛的神经科学应用中发挥变革性作用，因为DA、GLUT和ACh作为神经元间信号分子参与多个大脑区域，控制从学习和记忆到运动控制的大量功能。我们对它们在活体中的表现的评估将集中在纹状体，这是一个涉及运动控制和动机行为的大脑区域。多个递质释放事件与行为行为的精确耦合将为寻找治疗多种神经和精神疾病的干预措施提供有价值的信息。

DESCRIPTION (provided by applicant): Efforts to understand how neurons within networks interact to control behavior will be greatly facilitated by a means with which to measure multiple neuroactive molecules in the brain simultaneously and in near-real time. Existing methods either offer rapid measurements of a single analyte (e.g., fast-scan cyclic voltammetry) or provide multiple analyte measurement with insufficient temporal resolution (microdialysis). Here, we will develop an implantable microprobe capable of simultaneous rapid monitoring of 3 ubiquitous neurotransmitters/neuromodulators: dopamine (DA), glutamate (Glut), and acetylcholine (ACh). Further, we will harness the power of optogenetics by incorporating an optical waveguide into the microprobe providing directional illumination of tissue juxtaposed to each sensing electrode on the microelectrode array. This will be achieved using an innovative silica-based microprobe design with embedded waveguides and light splitters, and with a micromirror embedded underneath each microelectrode for uniform directional light illumination. The resultant microprobe will combine local modulation of genetically isolated neuron terminals with measurement of transmitter release from those terminals, together with resultant changes in the release of other transmitters from neurons within the network, all in the context of a freel behaving animal. These sensors will be transformative in a wide range of neuroscience applications due to the involvement of DA, Glut and ACh as inter-neuronal signaling molecules in multiple brain regions controlling a plethora of functions from learning and memory to motor control. Our evaluation of their performance in vivo will focus on the striatum, a brain region involved in motor control and motivated behavior. Precise coupling of multiple transmitter release events to behavioral actions will provide valuable information pertinent to the search for therapeutic interventions for multiple neurological and psychiatric disorders.