细胞内膜网膜和线粒体处理动态形状缓慢在血管压素磁细胞神经元的超极化后
Matthew K Kirchner1,2, Ferdinand Althammer1,2, Elba Campos-Lira1,2
1Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, Georgia 30303.
概括
细胞内膜网膜 (ER) 在血管压素 (VP) 神经元中激活缓慢的超极化后 (sAHPs). 线粒体缓冲,塑造sAHP信号并影响VP发射活动和荷尔蒙释放.
科学领域:
- 神经科学是一个神经科学.
- 细胞生理学 细胞生理学
- 内分泌学 在内分泌学.
背景情况:
- 超视核 (SON) 中的血管压素 (VP) 神经元因后超极化 (AHPs) 而表现出尖峰频率适应.
- AHP (sAHP) 机制的缓慢组成部分,特别是在VP神经元中,仍然不太了解,与催产素神经元不同.
- 之前的研究表明,在催产素神经元中存在N型Ca2+通道,但在VP神经元中没有明显的类似机制.
研究的目的:
- 研究细胞内处理器官,内网 (ER) 和线粒体在激活VP神经元中的sAHPs中的作用.
- 阐明ER和线粒体对VP神经元中sAHP信号传递的时空动态的贡献.
- 了解器官Ca2+动态如何影响VP神经元发射和全身激素释放.
主要方法:
- 在雄性和雌性Wistar鼠VP神经元中的电生理记录.
- 对ER Ca2+储量的药理学操纵 (例如,耗尽) 和线粒体功能 (例如,CCCP,MCU阻断剂,TPP+).
- 评估sAHP振幅,持续时间和Ca2+信号动态.
主要成果:
- ER Ca2+ 耗尽显著抑制了SAHPs,这表明ER Ca2+ 释放激活了SAHPs.
- 线粒体抑制 (CCCP) 或缓冲 (MCU阻断剂) 增强了sAHP的幅度和持续时间,表明线粒体作为Ca2+缓冲器.
- 阻断线粒体Na+依赖的Ca2+释放并没有影响sAHPs,排除了线粒体Ca2+释放作为直接激活剂.
结论:
- ER Ca2+释放激活VP神经元中的sAHPs,而线粒体通过Ca2+缓冲调节这些信号.
- 与ER-线粒体相关的膜接触点是Ca2+微域活性调节sAHP通路的关键位置.
- 这种基于有机体的Ca2+信号显著影响VP神经元发射活动和随后的全身激素释放.
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