Low-conductivity calcium channels in the macrophage plasma membrane: Activation by inositol-1,4,5-triphosphate

被引：8

作者：

Semenova S.B. ^{[1
]}

Kiselev K.I. ^{[1
]}

Mozhaeva G.N. ^{[1
]}

机构：

[1] Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretskii Prospekt

来源：

Neuroscience and Behavioral Physiology | 1999年 / 29卷 / 3期

基金：

俄罗斯基础研究基金会;

关键词：

Calcium channels; Inositol-1,4,5-triphosphate; Mouse macrophages; Phospholipase A2; Plasma membrane;

D O I：

10.1007/BF02465347

中图分类号：

学科分类号：

摘要：

Local voltage clamping was applied to mouse macrophage plasma membrane to study calcium channels activated by inositol-1,4,5-triphosphate (IP3) and blocked by heparin. These channels were clearly distinguished from IP3-activated channels of the endoplasmic reticulum by their low conductivity (about 1 pSm for 100 mM Ca2+), high selectivity for Ca2+ relative to K+ (PCa:PK > 1000), calcium inactivation, and activation on hyperpolarization; these properties allowed them to be assigned to the ICRAC family. On the other hand, the properties of the IP3 receptors of these channels (IP3R), i.e., the dose-dependent effect of IP3, the IP3 desensitization of the receptor, and the sensitivity to micromolar concentrations of heparin and arachidonic acid were close to those of the endoplasmic reticulum IP3 receptor. The most likely interpretation of these data is that IP3R are not located in the endoplasmic reticulum, but, acting via some kind of conformational change occurring on binding of IP3, transmit a signal from the endoplasmic reticulum to the highly selective Ca2+ channels. This point of view is in agreement with the published "coupling model" [1]. © 1999 Kluwer Academic/Plenum Publishers.

引用

页码：339 / 345

页数：6

共 23 条

[21]

Vaca, L., Kunze, D.L., Deletion of intracellular Ca2+ stores activates a Ca2+-Selective channel in vascular endothelium (1994) Am. J. Physiol., 267, pp. C920-C925

[22]

Vaca, L., Kunze, D.L., IP3-activated Ca2+ channels in the plasma membrane of cultured vascular endothelial cells (1995) Am. J. Physiol., 269, pp. C733-C738

[23]

Zweifach, A., Lewis, R.S., Mitogen-regulated Ca2+ current of T lymphocytes is activated by depletion of intracellular Ca2+ stores (1993) Proc. Natl. Acad. Sci. USA, 90, pp. 6295-6299

← 1 2 3 →