Synergetic activation of outwardly rectifying Cl− currents by hypotonic stress and external Ca2+ in murine osteoclasts
Synergetic activation of outwardly rectifying Cl− currents by hypotonic stress and external Ca2+ in murine osteoclasts
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小鼠破骨细胞中低渗应激和外部 Ca2+ 协同激活向外整流 Cl− 电流
DOI：
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
M. Kuno
中科院分区：
文献类型：
--
作者：
H. Sakai;F. Nakamura;M. Kuno
1低渗刺激激活小鼠破骨细胞的外向整流Cl−(ORCl)电流。该电流具有激活快、失活少、向外整流强、易被DIDS堵塞、对有机酸（丙酮酸和谷氨酸）具有渗透性等特点。2 .低渗激活的ORCl电流可以通过细胞内透析（用无ATP的移液溶液）来抑制，但不能通过用难水解的ATP类似物腺苷5′‐O‐（3‐硫代三磷酸）替代ATP来抑制。当细胞内碱度在pH 6.6 ~ 8.0范围内升高时，电流振幅减小。3细胞内应用细胞松弛素D在无低渗应激的情况下偶尔激活ORCl电流，但在低渗刺激下抑制ORCl电流的激活。低渗激活的ORCl电流不受非肌动蛋白解聚细胞松弛素（chaetoglobosin C）的影响，但被脱氧核糖核酸酶i部分抑制。4去除细胞外Ca2+可抑制低渗休克对ORCl电流的激活，但一旦激活，不会降低电流。用20 mm EGTA进行细胞内透析可部分降低低压激活的ORCl电流。当细胞外介质中含有10 mm Ca2+时，ORCl电流被激活，以响应渗透压比1 mm Ca2+更轻微的降低。细胞内Ca2+水平的增加（pCa 6.5）模拟了对低渗性的敏感性增加。这些结果表明，低渗刺激和细胞外Ca2+水平的升高协同激活小鼠破骨细胞的ORCl通道，并且激活过程受到多种细胞内因子（pH， ATP和肌动蛋白细胞骨架组织）的修饰。
1 An outwardly rectifying Cl− (ORCl) current of murine osteoclasts was activated by hypotonic stimulation. The current was characterized by rapid activation, little inactivation, strong outward rectification, blockage by DIDS and permeability to organic acids (pyruvate and glutamate). 2 The hypotonically activated ORCl current was inhibited by intracellular dialysis with an ATP‐free pipette solution, but not by replacement of ATP with a poorly hydrolysable ATP analogue adenosine 5′‐O‐(3‐thiotriphosphate). The current amplitude was reduced when intracellular alkalinity increased over the pH range 6.6–8.0. 3 Intracellular application of cytochalasin D occasionally activated the ORCl current without hypotonic stress, but inhibited activation of the ORCl current by hypotonic stimulation. The hypotonically activated ORCl current was unaffected by a non‐actin‐depolymerizing cytochalasin, chaetoglobosin C, but partially inhibited by deoxyribonuclease I. 4 Removal of extracellular Ca2+ inhibited activation of the ORCl current by hypotonic shock, but did not reduce the current once activated. The hypotonically activated ORCl current was partially decreased by intracellular dialysis with 20 mm EGTA. 5 With 10 mm Ca2+ in the extracellular medium, the ORCl current was activated in response to more minor decreases in osmolarity than with 1 mm Ca2+. The increased sensitivity to hypotonicity was mimicked by increasing the intracellular Ca2+ level (pCa 6.5). 6 These results suggest that hypotonic stimulation and a rise in the extracellular Ca2+ level synergistically activate the ORCl channel of murine osteoclasts, and that the activating process is modified by multiple intracellular factors (pH, ATP and actin cytoskeletal organization).
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影响因子：
2.9
作者：
SAMPATH, P;POLLARD, TD
通讯作者：
POLLARD, TD
DOI：
10.1172/jci115326
发表时间：
1991-08
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
B. A. Molitoris;A. Geerdes;J R McIntosh
通讯作者：
B. A. Molitoris;A. Geerdes;J R McIntosh
影响因子：
15.9
作者：
TETI, A;BLAIR, HC;HRUSKA, KA
通讯作者：
HRUSKA, KA
DOI：
10.1172/jci118197
发表时间：
1995-09
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
M. Zaidi;V. Shankar;R. Tunwell;O. Adebanjo;J. Mackrill;M. Pazianas;D. O'Connell;B. Simon;B. Rifkin;A. Venkitaraman
通讯作者：
M. Zaidi;V. Shankar;R. Tunwell;O. Adebanjo;J. Mackrill;M. Pazianas;D. O'Connell;B. Simon;B. Rifkin;A. Venkitaraman