运动神经末端的高神经分泌是依赖的过程吗?
Y Shimoni1, E Alnaes, R Rahamimoff
1Department of Physiology, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Nature
|May 12, 1977
概括
细胞外流体度升高显著增加神经末释放的神经递质. 这种超神经分泌取决于细胞内的度,影响神经信号传递.
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
- 生理学 生理学 生理学
背景情况:
- 自发的神经递质释放是由细胞外流体透压力调节的.
- 超度条件 (20-30%的度增加) 增强神经递质从运动神经末端的释放.
- 超神经分泌的机制及其对的依赖性尚未完全理解.
研究的目的:
- 为了研究细胞内度 ([Ca]in) 在超神经分泌中的作用.
- 为了测试增加[Ca]in导致超神经分泌的假设.
- 间接评估青神经肌肉突触中的[Ca]in.
主要方法:
- 利用间接技术估计青神经肌肉突触中的细胞内度 ([Ca]in).
- 假设的微型端板潜力 (m.e.p.p.) 频率反映在 [Ca] 中.
- 检查了改变电导率 (g(Ca)) 和电化学梯度对超神经分泌的影响.
主要成果:
- 发现超神经分泌取决于细胞内的度 ([Ca]in).
- 这项研究提供了证据,将增加的[Ca]in与在高透性条件下增强的神经递质释放联系起来.
- 间接测量表明m.e.p.p.之间的相关性. 频率和[Ca]in. 的情况.
结论:
- 超神经分泌取决于细胞内的度 ([Ca]in).
- 这些发现支持这样一个假设:高[Ca]in调解了超体应激对神经递质释放的影响.
- 这项研究有助于理解突触传输的调节.
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