EXCITATORY AMINO ACID TRANSMITTERS IN CNS

强有力的证据表明谷氨酸或天冬氨酸作为递质在 大鼠海马区某些兴奋性突触。这些突触 已被选为分析谷氨酸/天冬氨酸机制的模型。 已经确定了谷氨酸的两个不依赖于钠的结合部位，并 以制备海马区突触膜为特征。的作用 这些作为突触受体的结合部位将通过药理学进行评估。 以及与海马片突触反应的生理学比较 具有兴奋性氨基酸及其拮抗剂能力的制备 来调节这些脑片中钠离子通道的开放。肌肉 松弛剂，巴氯芬，已被提出在兴奋时选择性地起作用 利用氨基酸的突触将在以下时间测试其对传输的影响 海马区突触。神经兴奋性与致痫的关系 和酸性氨基酸的神经毒性活性将在 采用脑电和膜结扎技术建立大鼠海马区模型。 最后，巴氯芬和自身受体对谷氨酸释放的影响 天冬氨酸氨基转移酶将被检测。这些研究将有助于我们对 中枢神经系统中的兴奋性传递。他们的最终目标是 提供开发药物疗法所需的基本信息，目的是 兴奋性氨基酸系统。

Strong evidence suggests glutamate or aspartate as the transmitter employed at certain excitatory synapses in the rat hippocampal formation. These synapses have been selected as models for analysis of glutamate/aspartate mechanisms. Two sodium-independent binding sites for glutamate have been identified and characterized in preparations of hippocampal synaptic membranes. The role of these binding sites as synaptic receptors will be evaluated by pharmacological and physiological comparisons with synaptic responses in the hippocampal slice preparation and with the ability of excitatory amino acids and their antagonists to modulate the opening of sodium channels in these slices. The muscle relaxant, baclofen, which has been proposed to act selectively at excitatory amino acid-utilizing synapses, will be tested for its effects on transmission at hippocampal synapses. The relation between the neuroexcitatory, epileptogenic and neurotoxic activities of acidic amino acids will be further explored in the hippocampal model with use of electrographic and membraane binding techniques. Finally, the effects of baclofen and autoreceptors on the release of glutamate and aspartate will be examined. These studies will aid our understanding of excitatory transmission in the central nervous system. Their ultimate goal is to provide basic information needed to develop pharmacotherapies aimed at excitatory amino acid systems.