Ethanol, chloride, calcium and growth cone dynamics in embryonic GABAergic interneurons

项目摘要 胎儿酒精谱系障碍(FASD)是主要的可预防的神经发育障碍之一。 以不同程度的智力残疾为特点，包括认知、行为、感觉和身体上的残疾 赤字。虽然FASD的诊断和治疗是在出生后进行的，但潜在的病因学是 显然是胚胎，但仍未完全了解。在小鼠中，产前酒精暴露扰乱了错综复杂的 GABA能皮质中间神经元的切向迁移过程，这被认为有助于 皮层回路中的长期兴奋性/抑制性失衡和执行功能损害 一直持续到成年。乙醇是如何影响细胞过程而导致这种异常迁移的？在这 我将研究GABA能中间神经元迁移的潜在机制，以及这一机制是如何 可能会在酒精暴露后受到干扰。 到目前为止，我的初步数据表明，Na+-K+-2Cl-共转运体1(NKCC1)，L类型 电压门控性钙通道和细胞骨架动力学可能参与乙醇对钙离子通道的作用。 GABA能皮层中间神经元的迁移。在此基础上，我提出了两个既相互关联又相互独立的 明确的目标。特殊目标1将采用穿孔膜片钳记录和实时记录的组合 成像以测试乙醇与NKCC1相互作用以提高细胞内氯水平和 增强GABA受体对胚胎GABA能中间神经元的去极化作用。《特定目标2》将使用 荧光钙和肌动蛋白-微管成像验证乙醇改变L钙的假说 通道依赖性肌动蛋白-微管动力学改变胚胎GABA能皮质的切向迁移 中间神经元。 总体而言，通过F31计划，我寻求智力、概念和技术培训，这些培训将是 为我继续在FASD领域进行研究奠定了基础，重点是细胞和亚细胞 酒精对大脑发育过程中神经元迁移影响的潜在机制。拟议中的工作 将为未来乙醇如何影响亚细胞信号机制的研究奠定基础 作为移民进程的一部分，调动增长锥体，并为 乙醇如何影响切向迁移，并为预防或管理治疗策略的设计提供信息 FASD。

Project Summary Fetal alcohol spectrum disorder (FASD) is one of the leading preventable neurodevelopmental disorders hallmarked by varying degrees of intellectual disability that includes cognitive, behavioral, sensory, and physical deficits. While the diagnosis and management of FASD takes place postnatally, the underlying pathoetiology is clearly embryonic but remains incompletely understood. In mice, prenatal ethanol exposure disrupts the intricate process of tangential migration of GABAergic cortical interneurons, and this has been postulated to contribute to long-term excitatory/inhibitory imbalance within the cortical circuits and impairments in executive function that lasts into adulthood. What cellular processes does ethanol affect to result in this aberrant migration? In this proposal, I will investigate the mechanisms underlying the migration of GABAergic interneurons and how this might be disrupted following ethanol exposure. My preliminary data to date suggest that the Na+-K+-2Cl- co-transporter isoform 1 (NKCC1), L-type voltage-gated calcium channels, and cytoskeletal dynamics may be involved in the action of ethanol on the migration of GABAergic cortical interneurons. Building on this, I propose two inter-related yet independent specific aims. Specific Aim 1 will employ a combination of perforated patch clamp recording and real-time imaging to test the hypothesis that ethanol interacts with NKCC1 to elevate intracellular chloride levels and enhance GABAA receptor-induced depolarization in embryonic GABAergic interneurons. Specific Aim 2 will use fluorescence calcium and actin-microtubule imaging to test the hypothesis that ethanol alters L-type calcium channel-dependent actin-microtubule dynamics to alter tangential migration of embryonic GABAergic cortical interneurons. Overall, through this F31 proposal, I seek intellectual, conceptual, and technical training that will be foundational for me to continue conducting research in the field of FASD, focusing on the cellular and subcellular mechanisms underlying ethanol’s effect on neuronal migration during brain development. The proposed work will set the groundwork for future investigations on how ethanol affects the subcellular signaling mechanisms that mobilize the growth cone as part of the migration process, and contribute critical mechanistic insights into how ethanol affects tangential migration and inform the design of therapeutic strategies to prevent or manage FASD.