Department of Psychology, University of Wisconsin-Madison, Madison, Wisconsin 53706.
Department of Psychology, University of Wisconsin-Madison, Madison, Wisconsin 53706
J Neurosci. 2019 Mar 13;39(11):2080-2090. doi: 10.1523/JNEUROSCI.2701-18.2019. Epub 2019 Jan 16.
The PFC and extended frontostriatal circuitry support higher cognitive processes that guide goal-directed behavior. PFC-dependent cognitive dysfunction is a core feature of multiple psychiatric disorders. Unfortunately, a major limiting factor in the development of treatments for PFC cognitive dysfunction is our limited understanding of the neural mechanisms underlying PFC-dependent cognition. We recently demonstrated that activation of corticotropin-releasing factor (CRF) receptors in the caudal dorsomedial PFC (dmPFC) impairs higher cognitive function, as measured in a working memory task. Currently, there remains much unknown about CRF-dependent regulation of cognition, including the source of CRF for cognition-modulating receptors and the output pathways modulated by these receptors. To address these issues, the current studies used a viral vector-based approach to chemogenetically activate or inhibit PFC CRF neurons in working memory-tested male rats. Chemogenetic activation of caudal, but not rostral, dmPFC CRF neurons potently impaired working memory, whereas inhibition of these neurons improved working memory. Importantly, the cognition-impairing actions of PFC CRF neurons were dependent on local CRF receptors coupled to protein kinase A. Additional electrophysiological recordings demonstrated that chemogenetic activation of caudal dmPFC CRF neurons elicits a robust degradation of task-related coding properties of dmPFC pyramidal neurons and, to a lesser extent, medium spiny neurons in the dorsomedial striatum. Collectively, these results demonstrate that local CRF release within the caudal dmPFC impairs frontostriatal cognitive and circuit function and suggest that CRF may represent a potential target for treating frontostriatal cognitive dysfunction. The dorsomedial PFC and its striatal targets play a critical role in higher cognitive function. PFC-dependent cognitive dysfunction is associated with many psychiatric disorders. Although it has long-been known that corticotropin-releasing factor (CRF) neurons are prominent within the PFC, their role in cognition has remained unclear. Using a novel chemogenetic viral vector system, the present studies demonstrate that PFC CRF neurons impair working memory via activation of local PKA-coupled CRF receptors, an action associated with robust degradation in task-related frontostriatal neuronal coding. Conversely, suppression of constitutive PFC CRF activity improved working memory. Collectively, these studies provide novel insight into the neurobiology of cognition and suggest that CRF may represent a novel target for the treatment of cognitive dysfunction.
前额叶皮层和扩展的额眶部皮质回路支持指导目标导向行为的更高认知过程。前额叶皮层依赖的认知功能障碍是多种精神疾病的核心特征。不幸的是,开发治疗前额叶皮层认知功能障碍的治疗方法的一个主要限制因素是我们对前额叶皮层依赖认知的神经机制的理解有限。我们最近证明,在工作记忆任务中,激活尾侧背侧前额叶皮层(dmPFC)中的促肾上腺皮质释放因子(CRF)受体可损害更高的认知功能。目前,关于 CRF 依赖的认知调节仍有许多未知之处,包括用于调节认知的 CRF 受体的来源以及这些受体调节的输出途径。为了解决这些问题,目前的研究使用基于病毒载体的方法,在接受工作记忆测试的雄性大鼠中化学遗传激活或抑制前额叶皮层 CRF 神经元。化学遗传激活尾侧,但不是额侧 dmPFC CRF 神经元,可强烈损害工作记忆,而抑制这些神经元则可改善工作记忆。重要的是,前额叶皮层 CRF 神经元的认知损害作用取决于与蛋白激酶 A 偶联的局部 CRF 受体。额外的电生理记录表明,化学遗传激活尾侧 dmPFC CRF 神经元会引起 dmPFC 锥体神经元以及程度较轻的背侧纹状体中间神经元与任务相关的编码特性的显著降解。总的来说,这些结果表明,尾侧 dmPFC 内的局部 CRF 释放会损害额眶部皮质和回路的认知和功能,并表明 CRF 可能是治疗额眶部皮质认知功能障碍的潜在靶点。背侧前额叶皮层及其纹状体靶区在更高的认知功能中起着至关重要的作用。前额叶皮层依赖的认知功能障碍与许多精神疾病有关。尽管人们早就知道促肾上腺皮质释放因子(CRF)神经元在前额叶皮层中很突出,但它们在认知中的作用仍不清楚。使用新型化学遗传病毒载体系统,本研究表明,通过激活局部与 PKA 偶联的 CRF 受体,PFC CRF 神经元损害工作记忆,这一作用与与任务相关的额眶部皮质神经元编码的显著降解有关。相反,抑制 PFC CRF 活性可改善工作记忆。总的来说,这些研究为认知神经生物学提供了新的见解,并表明 CRF 可能是治疗认知功能障碍的新靶点。