Striatal Regulation of Cortical Acetylcholine Release

基底神经节通过皮质-纹状体-丘脑-皮质环调节皮质功能。两个功能上 相反的通路直接和间接通路通过 基底神经节输出核、苍白球和黑质。最近的切片生理学实验， 然而，这表明纹状体调节皮质活动的另一个更直接的联系。在切片中， 背侧纹状体的直接和间接通路神经元抑制投射到额叶的胆碱能神经元， 皮质区接受纹状体抑制性胆碱能神经元输入的一个区域是眶额 皮质（OFC）。眶额皮层支持逆向学习，这是一种衡量行为灵活性的方法， 精神障碍包括强迫症、精神分裂症和药物成瘾。引人注目的是， 关于胆碱能神经元对眶额皮层的调节，无论是胆碱能投射到眶额皮层， 眶额皮层对逆转学习的调节及胆碱能神经向眶额皮层的投射是否受纹状体调节 在行为上。这种探索性的R21应用是解决这些知识差距的第一步。我们将 使用鼠标和鼠标可用的现代电路解剖工具来测试总体 直接和间接通路通过抑制OFC投射调节反向学习假说 胆碱能神经元为了解决这一假设，我们提出以下两个目标： 目的1：研究向眶额皮层投射的胆碱能神经元是否支持反转学习 在目的1.1中，我们将使用Ca 2+成像来测量OFC投射胆碱能神经元的活性。目标1.2 我们将抑制OFC投射的胆碱能神经元，并确定它如何影响皮质乙酰胆碱的释放。 和逆向学习。 目的2：研究纹状体是否通过胆碱能系统调节逆转学习 在aim 1.2和aim 1.2中，我们将在逆转学习过程中抑制间接或直接通路神经元，以确定 这是如何影响皮层乙酰胆碱释放和反向学习的。 了解基底神经节在调节OFC功能和逆转学习中的作用， 皮质-纹状体回路异常和逆转受损对脑疾病的重要意义 学习障碍包括精神分裂症、强迫症和药物成瘾。

The basal ganglia regulate cortical function via cortico-striatal-thalamo-cortical loops. Two functionally opposing pathways the direct and indirect pathway either activate or inhibit thalamo-cortical circuits via the basal ganglia output nuclei, the globus pallidus and the substantia nigra. Recent slice physiology experiments, however, suggest an additional more direct link by which the striatum regulates cortical activity. In slices both direct and indirect pathway neurons of the dorsal striatum inhibit cholinergic neurons that project to frontal cortical areas. One area that receives inputs from striatal-inhibited cholinergic neurons is the orbitofrontal cortex (OFC). The OFC supports reversal learning a measure of behavioral flexibility that is affected in several mental disorders including obsessive-compulsive disorder, schizophrenia and drug addiction. Strikingly, not much is known about the regulation of the OFC by cholinergic neurons, whether cholinergic projections to the OFC modulate reversal learning and whether cholinergic projections to the OFC are regulated by the striatum during behavior. This explorative R21 application is a first step to address these gaps in knowledge. We will use the mouse and the modern circuit dissection tools available to the mouse to test the overarching hypothesis that direct and indirect pathways regulate reversal learning via inhibition of OFC-projecting cholinergic neurons. To address this hypothesis we propose the following two aims: Aim 1: To determine whether cholinergic neurons projecting to the OFC support reversal learning In aim 1.1 we will use Ca2+ imaging to measure the activity of OFC-projecting cholinergic neurons. In aim 1.2 we will inhibit OFC-projecting cholinergic neurons and determine how this affects cortical acetylcholine release and reversal learning. Aim 2: To determine whether the striatum regulates reversal learning via the cholinergic system In aim 1.2 and aim 1.2 we will inhibit indirect or direct pathway neurons during reversal learning to determine how this affects cortical acetylcholine release and reversal learning. Understanding the role of the basal ganglia in regulating OFC function and reversal learning will have important implications for brain disorders with abnormalities in cortico-striatal circuitry and impaired reversal learning including schizophrenia, obsessive-compulsive disorder and drug addiction.