相关实验视频
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Measuring Fast Calcium Fluxes in Cardiomyocytes
Published on: November 29, 2011
脉冲性细胞内的释放并不取决于内醇三酸度的波动
M Wakui1, B V Potter, O H Petersen
1MRC Secretory Control Research Group, University of Liverpool, UK.
Nature
|May 25, 1989
概括
激素通过伊诺西三酸盐 (InsP3) 触发细胞振荡. 这项研究表明,即使在恒定的InsP3水平下,的释放也可能是规律的,这挑战了现有的模型.
科学领域:
- 细胞生理学 细胞生理学
- 生物化学 生物化学
- 信号通道的信号通道.
背景情况:
- 细胞信号包括细胞内度 ([Ca2+]i) 的振荡.
- 伊诺西三酸盐 (InsP3) 是一个关键的信使,刺激细胞内储存的释放.
- 当前的模型通常假设波动的InsP3水平驱动[Ca2+]i振荡.
研究的目的:
- 为了研究产生正常的细胞内振荡的机制,在不可激发的细胞.
- 为了确定恒定的内醇三酸盐 (InsP3) 水平是否能产生定期的释脉冲.
- 挑战现有模型,即波动的InsP3对于[Ca2+]i振荡至关重要.
主要方法:
- 通过Ca2+激活的Cl-电流在单个小鼠胰腺细胞中监测细胞内度 ([Ca2+]i).
- 用乙胆 (ACh) 刺激细胞,并通过补丁管 pipette 通过 inositol 三酸盐 (InsP3) 和其模拟物 (InsPS3) 应用.
- 进行带有和没有外部的实验,以及用细胞内化剂.
主要成果:
- 乙胆 (ACh) 和InsP3引起了Ca2+激活的Cl-电流的定期,重复的脉冲,表明有规律的释放.
- 非代谢的InsP3类似物InsPS3也会产生定期的释放脉冲.
- 这些释放事件独立于外部,但对细胞内化敏感.
结论:
- 反复的细胞内释放可以发生,即使因诺西三酸盐 (InsP3) 的度保持不变.
- 这一发现表明,除了波动的InsP3水平外,其他机制也有助于定期的振荡.
- 这项研究提供了证据,证明不需要波动的InsP3来产生规律的[Ca2+]i振荡.
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