Spatial distribution of Ca(2+) signals during repetitive depolarizing stimuli in adrenal chromaffin cells.
Spatial distribution of Ca(2+) signals during repetitive depolarizing stimuli in adrenal chromaffin cells.
复制标题
肾上腺嗜铬细胞重复去极化刺激期间 Ca(2) 信号的空间分布。
DOI：
10.1016/s0006-3495(03)74759-6
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Monck,JonathanR
中科院分区：
文献类型：
--
作者：
Marengo,FernandoD;Monck,JonathanR
肾上腺嗜铬细胞的胞吐作用受刺激方式的强烈影响。为了了解潜在的Ca 2+信号的动态和空间特性，我们使用脉冲激光Ca 2+成像来捕获在通过单一和重复去极化刺激的刺激期间的Ca 2+梯度。如前所述，短的单脉冲（10- 100 ms）导致膜下Ca 2+梯度的形成（F. D.马伦戈和J. R. Monck，2000，Biophysical Journal，79：1800-1820）。用多个脉冲串（每个50 ms，2 Hz）的重复刺激产生细胞内Ca 2+增加的模式，其从单脉冲后观察到的典型Ca 2+梯度逐渐变化为整个细胞中的Ca 2+增加，其峰值为单脉冲结束时获得的最大值的3-4倍。在七个或更多个脉冲之后，细胞内部的荧光增加通常大于膜下区域。Ca 2+梯度的模式没有修改的抑制剂的Ca 2+诱导的Ca 2+释放（ryanodine），抑制剂的IP 3诱导的Ca 2+释放（xestospongin），或设计用于耗尽细胞内Ca 2+存储（毒胡萝卜素）的治疗。然而，我们发现，大的荧光增加在细胞内部空间共定位与细胞核。这些结果可以用Ca 2+再分布的数学模型来模拟，其中细胞核通过主动或被动运输机制吸收Ca 2+。这些结果表明，嗜铬细胞可以响应去极化刺激不同的动态Ca 2+信号在膜下空间，胞质和核。
Exocytosis in adrenal chromaffin cells is strongly influenced by the pattern of stimulation. To understand the dynamic and spatial properties of the underlying Ca2+signal, we used pulsed laser Ca2+imaging to capture Ca2+gradients during stimulation by single and repetitive depolarizing stimuli. Short single pulses (10–100ms) lead to the development of submembrane Ca2+gradients, as previously described (F. D. Marengo and J. R. Monck, 2000,Biophysical Journal, 79:1800–1820). Repetitive stimulation with trains of multiple pulses (50ms each, 2Hz) produce a pattern of intracellular Ca2+increase that progressively changes from the typical Ca2+gradient seen after a single pulse to a Ca2+increase throughout the cell that peaks at values 3–4 times higher than the maximum values obtained at the end of single pulses. After seven or more pulses, the fluorescence increase was typically larger in the interior of the cell than in the submembrane region. The pattern of Ca2+gradient was not modified by inhibitors of Ca2+-induced Ca2+release (ryanodine), inhibitors of IP3-induced Ca2+release (xestospongin), or treatments designed to deplete intracellular Ca2+stores (thapsigargin). However, we found that the large fluorescence increase in the cell interior spatially colocalized with the nucleus. These results can be simulated using mathematical models of Ca2+redistribution in which the nucleus takes up Ca2+by active or passive transport mechanisms. These results show that chromaffin cells can respond to depolarizing stimuli with different dynamic Ca2+signals in the submembrane space, the cytosol, and the nucleus.
来自人胎盘的胰岛素和表皮生长因子刺激的蛋白激酶的比较。
影响因子：
4.8
作者：
L. Pike;E. Kuenzel;J. Casnellie;E. Krebs
通讯作者：
E. Krebs