The role L-type calcium channels (LTCCs) in regulating dopaminergic activity during cocaine abstinence

这项提议的总体目标是研究内源性大麻素(ECB)信号在 调节不同的皮质抑制性突触。脑的生理发育和功能是 依赖于突触兴奋和抑制的微调平衡。因此，抑制的失调 与多种神经发育障碍有关。细胞的目标和后果 成年动物体内的GABA能信号是众所周知的，然而特定的中间神经元受 欧洲央行的信号研究仍然很少。皮质抑制是由不同的GABA能基因群介导的 中间神经元(INS)，包括共表达钙结合蛋白小白蛋白(PV)的细胞。 递质生长抑素(SOM)，或5-羟色胺5HT3a受体。皮质胰岛素在突触靶点上有所不同， PV-INS与靶锥体神经元周围和近端树突区域形成突触 以及SOM-INS在树枝乔木上建立连接。5HT3a-in的子集，表示 血管活性肠肽(VIP)，支配锥体神经元和其他中间神经元的树突。这 亚细胞定位允许PV-INS调节PN尖峰输出和SOM-INS的大小和时间 调节树突棘和干钙内流以及谷氨酸能突触的可塑性。当孩子出生的时候 GABA能INS的迁移是众所周知的，在我们对分子和 影响抑制信号的细胞机制。ECB影响突触发生和长期可塑性 兴奋性和抑制性连接。尽管数据显示大麻素型-1共表达 (CB1)受体与SOM或VIP结合，CB1受体在不同的中间神经元内共定位 已经进行了研究，并将在本提案中予以解决。皮层ECB释放对突触前GABA的调节作用 释放并可驱动短期和长期抑制传递的抑制，然而身份 对ECB活动敏感的突触前INS还没有得到很好的描述。此外，CB1的后果 不同中间神经元的受体丢失尚不清楚。在这项提案中，我们试图确定欧洲央行的信号 调节不同IN群体介导的GABA能信号转导。我们假设欧洲央行发出的信号 调节皮质活动，在影响树突状细胞靶向介导的可塑性中起关键作用 中间神经元。我们提出了一种新的工具组合，包括电生理学、双光子激光扫描 显微镜(2PLSM)和基因靶向INS在小鼠初级视觉中的光遗传刺激 大脑皮层。我们的实验将为GABA的发展提供前所未有的洞察力 大脑皮层的回路。

The overall goal of this proposal is to investigate the role of endocannabinoid (ECB) signaling in regulating distinct cortical inhibitory synapses. Physiological brain development and function are dependent on a fine-tuned balance of synaptic excitation and inhibition. As such, dysregulation of inhibition has been implicated in a variety of neurodevelopmental disorders. The cellular targets and consequences of GABAergic signaling in adult animals is well understood, however the specific interneurons modulated by ECB signaling remains poorly studied. Cortical inhibition is mediated by a diverse group of GABAergic interneurons (INs), including cells co-expressing the calcium binding protein parvalbumin (PV), the peptide transmitter somatostatin (SOM), or the serotonin 5HT3a receptor. Cortical INs differ in their synaptic targets, with PV-INs making synapses onto the perisomatic and proximal dendritic regions of target pyramidal neurons and SOM-INs making connections onto the dendritic arbors. A subset of 5HT3a-INs which express the vasoactive intestinal peptide (VIP), innervate dendrites of pyramidal neurons and other interneurons. This subcellular localization allows PV-INs to regulate the magnitude and timing of PN spike output and SOM-INs to regulate dendritic spine and shaft calcium influx along with glutamatergic synaptic plasticity. While the birth and migration of GABAergic INs is well understood, there remain gaps in our knowledge of the molecular and cellular mechanisms that influence inhibitory signaling. ECBs influence synaptogenesis and long-term plasticity of both excitatory and inhibitory connections. Although data has shown coexpression of the cannabinoid type-1 (CB1) receptor with SOM or VIP, colocalization of the CB1 receptor within the various interneurons has not been studied and will be addressed in this proposal. ECB release in the cortex modulates presynaptic GABA release and can drive both short- and long-term depression of inhibitory transmission, however the identity of the presynaptic INs sensitive to ECB activity is not well-characterized. Moreover, the consequences of CB1 receptor loss from distinct interneurons is unknown. In this proposal, we seek to determine how ECB signaling modulates GABAergic signaling mediated by distinct IN populations. We hypothesize that ECB signaling modulates cortical activity, with a key role in influencing plasticity mediated by dendritic targeting interneurons. We propose a novel combination of tools including electrophysiology, 2-photon laser-scanning microscopy (2PLSM), and optogenetic stimulation of genetically-targeted INs in the mouse primary visual cortex. Our experiments will provide an unprecedented level of insight into the development of GABAergic circuits in the neocortex.