Intracellular Ca2+ stores and extracellular Ca2+ are required in the real-time Ca2+ response of bone cells experiencing fluid flow
Intracellular Ca2+ stores and extracellular Ca2+ are required in the real-time Ca2+ response of bone cells experiencing fluid flow
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DOI：
10.1016/0021-9290(96)84536-2
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发表时间：
1996-11-01
影响因子：
2.4
通讯作者：
Brighton, CT
中科院分区：
文献类型：
--
作者：
Hung, CT;Allen, FD;Brighton, CT
在这项研究中，我们试图确定是否有一个要求钙从细胞外空间以及钙从细胞内存储产生实时的细胞内钙反应，在培养的骨细胞进行流体流动。了解钙细胞信号传导可能有助于阐明介导液体向细胞信号转化的生物物理转导机制。一个实验设计，利用药理学阻断剂的计划，以区分参与这种细胞信号转导的生化途径。以平行板的dow小室作为细胞刺激装置，用荧光显微镜系统以钙敏感染料fura-2测定细胞内钙的变化。在本研究中，肌醇-磷脂生化途径，特别是肌醇三磷酸（IP 3）的作用的证据，获得了使用新霉素，完全抑制钙响应流量。此外，通过在无钙培养基中进行的实验证明了细胞外钙的伴随作用，该实验也消除了dow反应。用钆（一种牵张激活的通道阻断剂）进行的实验部分抑制（约30%）dow反应，而维拉帕米（一种L型电压敏感的通道阻断剂）对流量反应没有影响。这些结果表明，需要细胞外钙（或钙内流）以及IP 3诱导的钙释放从细胞内存储产生的细胞内钙响应在骨细胞中流动。版权所有（C）1996 Elsevier Science Ltd.
In this study, we sought to determine if there is a requirement for calcium entry from the extracellular space as well as calcium from intracellular stores to produce real-time intracellular calcium responses in cultured bone cells subjected to fluid flow. Understanding calcium cell signaling may help to elucidate the biophysical transduction mechanism(s) mediating the conversion of fluid dow to a cellular signal. An experimental design which utilized a scheme of pharmacological blockers was employed to distinguish between the biochemical pathways involved in this cell signaling. A parallel-plate dow chamber served as the cell stimulating apparatus and a fluorescence microscopy system using the calcium-sensitive dye fura-2 measured the intracellular calcium changes. In the present study, evidence for a role by the inositol-phospholipid biochemical pathway, specifically inositol trisphosphate (IP3) was obtained using neomycin which completely inhibited the calcium response to flow. Additionally, a concomitant role of extracellular calcium was demonstrated through experiments performed in calcium-free medium which also eliminated the dow response. Experiments conducted with gadolinium, a stretch-activated channel blocker, partially Inhibited (similar to 30%) the dow response while verapamil, a type-L voltage sensitive channel blocker, had no effect on the flow response. These results suggest a requirement of extracellular calcium (or calcium influx) as well as IP3-induced calcium release from intracellular stores for generating the intracellular calcium response to flow in bone cells. Copyright (C) 1996 Elsevier Science Ltd.