通过激发性GABAergic通路调节时钟时间和输出
Claire Gizowski1, Charles W Bourque2
1Brain Repair and Integrative Neuroscience Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada. cgizowski@gmail.com.
Nature
|July 10, 2020
概括
这项研究揭示了盐的摄入如何向大脑的主钟 - - 上神经核 (SCN) 发出信号,调节体温和活动时间. 这些发现表明非光线可以调节昼夜节律和静止反应.
科学领域:
- 神经科学
- 时间生物学
- 生理学
背景情况:
- 上神经核 (SCN) 作为身体的主生理时钟,协调日常生理和行为节奏.
- SCN影响水平衡和体温调节,部分是通过对抗夜间脱水.
- 目前尚不清楚可检测体液平衡变化的透传感器是否依赖于SCN输出通路进行平静控制.
研究的目的:
- 调查度传感器是否需要时钟输出网络来启动平静反应.
- 确定SCN血管压素 (VP) 神经元在调解对透挑战的反应中的作用.
- 阐明透信息传递到SCN的途径.
主要方法:
- 在特定的昼夜时间内给小鼠注射全身高血压盐水.
- 对SCNVP和血管膜末端器官 (OVLT) 神经元进行化学和光遗传学操纵.
- 电生理学记录和非发热的行为分析,体温和昼夜运动活动.
主要成果:
- 高血压盐水激发SCNVP神经元并降低非热和体温,这些影响取决于SCNVP神经元的活动.
- 通过GABAergic刺激将奥斯摩斯信息传递给SCNVP神经元的奥斯摩斯感应OVLT神经元表达谷氨酸脱酶 (OVLTGAD).
- OVLTGAD→SCNVP通路的激活模仿了高血效应,而OVLTGAD神经元的抑制则阻断了这些反应.
- 高血压盐水和OVLTGAD→SCNVP通路激活阶段的昼夜运动活动,这种效应被OVLTGAD神经元抑制.
结论:
- 这项研究表明,非光学信号,如盐摄入量,可以调节主昼夜钟 (SCN).
- 透挑战通过OVLTGAD→SCNVP途径激活SCNVP神经元,触发像降低热生成这样的平静反应.
- 这些发现突出了生理状态可以影响昼夜时间的机制,并驱动预测性或反应性平衡调整.
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