天体细胞Ca2+引起的ATP释放调节了髓化轴突刺激性和导电速度
Jonathan Lezmy1, I Lorena Arancibia-Cárcamo1,2, Tania Quintela-López1
1Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK.
概括
大脑白质中的星球细胞通过释放腺来调节髓化轴突功能. 它控制神经元刺激和信号速度,影响大脑信息流动.
科学领域:
- 神经科学是一个神经科学.
- 细胞生物学 细胞生物学
- 神经生理学 神经生理学
背景情况:
- 众所周知,星体细胞调节灰色物质中的突触.
- 星球细胞在白质中的功能,特别是关于髓质轴突的功能,仍然在很大程度上未被探索.
研究的目的:
- 为了研究星体细胞在调节大脑白质中的髓化轴突的功能中的作用.
- 阐明星体细胞通过哪些分子机制影响轴突刺激性和动作潜能传播.
主要方法:
- 利用动物模型监测细胞内度 ([Ca2+]i) 在近轴突初始段 (AIS) 和Ranvier的节点的天体细胞过程中.
- 研究了腺三酸盐 (ATP) 的释放及其转化为腺的过程.
- 研究了A2a受体和HCN2通道在响应天体细胞信号传递时的激活.
主要成果:
- 神经元活动增加了AIS和Ranvier节点附近的天体细胞细胞内 ([Ca2+]i).
- 这种的增加触发了腺三酸盐 (ATP) 的释放,它被转化为腺.
- 通过A2a受体作用的天体细胞衍生腺,调节HCN2通道,影响AIS刺激性和动作潜力的传播速度.
结论:
- 星球细胞通过一种由腺介导的途径,积极调节白质中的髓轴突功能.
- 天体细胞信号影响神经元刺激性和白质中信息传输的速度.
- 天体细胞衍生的腺水平的变化,受生理状态 (如觉醒/睡眠或能量剥夺) 的影响,可以调节白质信息流和神经电路功能.
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