Rutherford Erin C, Pomerleau Francois, Huettl Peter, Strömberg Ingrid, Gerhardt Greg A
Anatomy and Neurobiology, Morris K. Udall Parkinson's Disease Research Center of Excellence, Center for Sensor Technology, University of Kentucky, College of Medicine, Lexington, Kentucky 40536-0098, USA.
J Neurochem. 2007 Aug;102(3):712-22. doi: 10.1111/j.1471-4159.2007.04596.x.
l-glutamate (Glu) is the main excitatory neurotransmitter in the central nervous system (CNS) and is associated with motor behavior and sensory perception. While microdialysis methods have been used to record tonic levels of Glu, little is known about the more rapid changes in Glu signals that may be observed in awake rats. We have reported acute recording methods using enzyme-based microelectrode arrays (MEA) with fast response time and low detection levels of Glu in anesthetized animals with minimal interference. The current paper concerns modification of the MEA design to allow for reliable measures in the brain of conscious rats. In this study, we characterized the effects of chronic implantation of the MEA into the brains of rats. We were capable of measuring Glu levels for 7 days without loss of sensitivity. We performed studies of tail-pinch induced stress, which caused a robust biphasic increase in Glu. Histological data show chronic implantation of the MEAs caused minimal injury to the CNS. Taken together, our data show that chronic recordings of tonic and phasic Glu can be carried out in awake rats for up to 17 days in vivo allowing longer term studies of Glu regulation in behaving rats.
L-谷氨酸（Glu）是中枢神经系统（CNS）中的主要兴奋性神经递质，与运动行为和感觉知觉相关。虽然微透析方法已被用于记录Glu的稳态水平，但对于清醒大鼠中可能观察到的Glu信号更快速变化知之甚少。我们已经报道了使用基于酶的微电极阵列（MEA）的急性记录方法，该方法在麻醉动物中具有快速响应时间和低Glu检测水平，且干扰最小。本文涉及MEA设计的改进，以实现对清醒大鼠大脑的可靠测量。在本研究中，我们对MEA长期植入大鼠大脑的影响进行了表征。我们能够在不丧失敏感性的情况下测量Glu水平达7天。我们进行了尾部夹捏诱导应激的研究，该应激导致Glu出现强烈的双相增加。组织学数据表明MEA的长期植入对中枢神经系统造成的损伤最小。综上所述，我们的数据表明，在清醒大鼠体内可以进行长达17天的Glu稳态和相位的长期记录，从而能够对行为大鼠的Glu调节进行更长期的研究。
