Altered functions of ion channels, membrane receptors and neuronal networks associated with thalamocortical dysrhythmia syndrome.

与丘脑皮质心律失常综合征相关的离子通道、膜受体和神经元网络的功能改变。

• 批准号: 353966806
• 负责人: Professor Dr. Thomas Budde
• 金额: --
• 依托单位: Consejo Nacional de Investigaciones Científicas y Técnicas
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/353966806?language=en
• 关键词: Altered; functions; ion; channels; membrane

Thalamic abnormalities are common in neurological and psychiatric diseases (e. g., absence epilepsy, cocaine abuse). Based on the presence of slow delta and theta range bursting during wakefulness they are referred to as thalamocortical dysrhythmia syndromes. A hyperpolarized membrane potential of thalamocortical (TC) neurons is suggested to be the basis for aberrant burst activity. Neuronal hyperpolarization may occur by excess inhibition, deafferentation or block of NMDA receptors. However sensory deprivation and enhanced function of K+ channels, both potentially inducing membrane hyperpolarizations, have not been considered yet. Members of the K2P channel family crucially contribute to the generation of the hyperpolarized resting membrane potential in neurons. In order to be able to fully address the possible contribution of K2P channels to thalamocortical dysrhythmia, it is necessary to characterize the cellular signaling pathways modulating these channels in different thalamic cell types. Concerning this aspect, information is completely missing for GABAergic thalamic neurons (local interneurons; neurons of the reticular thalamic nucleus, NRT).The aims of the project are: (1) To determine the function of K2P channels in GABAergic thalamic neurons. (2) To determine the influence of psychostimulants and K2P channel activators / inhibitors on cellular and network activity. Since psychostimulants act via the increased availability of monoamines, especially dopamine, we will analyze dopaminergic pathways. (3) To determine the role of K2P channels in sensory deprivation as a new model of thalamocortical dysrhythmia based on deafferentation.The experimental approach will be: (1) PCR and immunohistochemical staining will be used to determine the expression and location of ion channels and membrane receptors. (2) Whole-cell patch-clamp recordings will be performed to determine electrophysiological and pharmacological properties of ion channels and membrane receptors in different thalamic cell types. GABAergic neurons will be directly targeted in knock-in mice expressing enhanced green fluorescent protein (EGFP) under the control of the glutamate decarboxylase 67 promotor (GAD67-EGFP). (3) Network activity will be addressed by performing local field potential (LFP) recordings in horizontal thalamic slices and thalamocortical slices of the somatosensory system (i.e., containing the ventrobasal thalamic complex; NRT; primary somatosensory cortex). (4) System function will be determined by combining LFP / single unit recordings in the somatosensory system and behavioral analysis in vivo. (5) As experimental animal models K2P channel knock out mice and unilateral sensory deprivation in mice by trimming of whiskers will be used.The results of the proposed study will help to determine new functional roles and possible pathological influences of K2P channels and their therapeutic potential in thalamocortical dysrhythmia syndromes.

丘脑异常在神经和精神疾病中很常见（例如，例如，在一个实施例中，失神癫痫、可卡因滥用）。基于在清醒期间缓慢的δ和θ范围爆发的存在，它们被称为丘脑皮质节律障碍综合征。丘脑皮层（TC）神经元的超极化膜电位被认为是异常爆发活动的基础。神经元超极化可通过过度抑制、去传入或阻断NMDA受体而发生。然而，感觉剥夺和增强K+通道的功能，这两个潜在的诱导膜超极化，尚未被考虑。K2 P通道家族的成员对神经元中超极化静息膜电位的产生至关重要。为了能够充分解决K2 P通道对丘脑皮质节律障碍的可能贡献，有必要表征在不同丘脑细胞类型中调节这些通道的细胞信号传导途径。关于这方面的信息是完全缺失的GABA能丘脑神经元（局部中间神经元;丘脑网状核的神经元，NRT）。本项目的目的是：（1）确定GABA能丘脑神经元中K2 P通道的功能。(2)确定精神兴奋剂和K2 P通道激活剂/抑制剂对细胞和网络活动的影响。由于精神兴奋剂通过增加单胺的可用性，特别是多巴胺，我们将分析多巴胺能通路。(3)为探讨K2 P通道在感觉剥夺中的作用，建立一种基于传入神经阻滞的丘脑皮质节律障碍模型，实验方法为：（1）采用PCR和免疫组织化学染色方法检测K2 P通道和膜受体的表达和定位。(2)将进行全细胞膜片钳记录，以确定不同丘脑细胞类型中离子通道和膜受体的电生理学和药理学特性。在谷氨酸脱羧酶67启动子（GAD 67-EGFP）的控制下，GABA能神经元将在表达增强型绿色荧光蛋白（EGFP）的敲入小鼠中被直接靶向。(3)将通过在躯体感觉系统的水平丘脑切片和丘脑皮质切片中进行局部场电位（LFP）记录来解决网络活动（即，包含腹基底丘脑复合体; NRT;初级躯体感觉皮层）。(4)将通过结合体感系统中的LFP /单个单元记录和体内行为分析来确定系统功能。(5)作为实验动物模型，将使用K2 P通道敲除小鼠和通过修剪胡须的单侧感觉剥夺小鼠，所提出的研究结果将有助于确定K2 P通道的新的功能作用和可能的病理影响以及它们在丘脑皮质节律障碍综合征中的治疗潜力。