Capacitative Ca2+ entry is closely linked to the filling state of internal Ca2+ stores: a study using simultaneous measurements of ICRAC and intraluminal [Ca2+].
Capacitative Ca2+ entry is closely linked to the filling state of internal Ca2+ stores: a study using simultaneous measurements of ICRAC and intraluminal [Ca2+].
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DOI：
10.1083/jcb.140.2.325
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发表时间：
1998-01-26
期刊：
影响因子：
--
通讯作者：
Pozzan T
中科院分区：
文献类型：
--
作者：
Hofer AM;Fasolato C;Pozzan T
ICRAC（最好的特征钙电流激活的存储耗尽）同时监测第一次与[Ca 2 +]变化的内部存储。为了建立这两个参数之间的定量和动力学关系，我们已经开发出一种新的手段来钳[Ca 2 +]内存储的完整细胞在任何水平。该方法基于膜渗透性低亲和力Ca 2+螯合剂N，N，N′，N′-四（2-吡啶甲基）乙二胺（TPEN），其优点是在不改变Ca 2+泵或释放通道的情况下，ER内的[Ca 2 +]可以在10-15 s内降低并恢复到其原始水平。使用这些新的工具，我们在这里证明，钙释放激活的钙电流（ICRAC）激活（a）仅通过减少ER内的游离[Ca 2 +]和（B）通过任何可测量的减少[Ca 2 +]ER。我们还表明，失活的内在动力学是相对缓慢的，可能依赖于可溶性因子，在全细胞记录过程中丢失。
ICRAC (the best characterized Ca2+ current activated by store depletion) was monitored concurrently for the first time with [Ca2+] changes in internal stores. To establish the quantitative and kinetic relationship between these two parameters, we have developed a novel means to clamp [Ca2+] within stores of intact cells at any level. The advantage of this approach, which is based on the membrane-permeant low-affinity Ca2+ chelator N,N,N′,N′-tetrakis (2-pyridylmethyl)ethylene diamine (TPEN), is that [Ca2+] within the ER can be lowered and restored to its original level within 10–15 s without modifications of Ca2+ pumps or release channels. Using these new tools, we demonstrate here that Ca2+ release–activated Ca2+ current (ICRAC) is activated (a) solely by reduction of free [Ca2+] within the ER and (b) by any measurable decrease in [Ca2+]ER. We also demonstrate that the intrinsic kinetics of inactivation are relatively slow and possibly dependent on soluble factors that are lost during the whole-cell recording.
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影响因子：
64.8
作者：
HOTH, M;PENNER, R
通讯作者：
PENNER, R
影响因子：
4.8
作者：
Hofer, AM;Curci, S;Schulz, I
通讯作者：
Schulz, I
DOI：
10.1073/pnas.90.7.2598
发表时间：
1993-04-01
影响因子：
11.1
作者：
HOFER, AM;MACHEN, TE
通讯作者：
MACHEN, TE
影响因子：
64.8
作者：
PAREKH, AB;TERLAU, H;STUHMER, W
通讯作者：
STUHMER, W
影响因子：
4
作者：
Hofer, AM;Schulz, I
通讯作者：
Schulz, I