Chelation of cytoplasmic Ca2+ increases plasma membrane permeability in murine macrophages.
Chelation of cytoplasmic Ca2+ increases plasma membrane permeability in murine macrophages.
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细胞质 Ca2+ 的螯合增加了小鼠巨噬细胞的质膜通透性。
DOI：
10.1016/s0021-9258(19)39409-8
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
F. Di Virgilio
中科院分区：
文献类型：
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作者：
E. Picello;P. Pizzo;F. Di Virgilio
通过在缺乏外部 Ca2+ 的情况下与 quin2 乙酰氧基甲酯一起孵育，将巨噬细胞系 J774 中的细胞质游离 Ca2+ (Ca2+i) 螯合至 10-20 nM（Di Virgilio, F., Lew, P.D. 和 Pozzan, T. (1984) Nature 310, 691-693）或通过加载[乙烯双(氧亚乙基次氮基)]四乙酸(EGTA)通过细胞外ATP对质膜的可逆透化作用进入细胞质(Steinberg, T.H., Newman, A.S., Swanson, J.A., and Silverstein, SS.C. (1987) J. Biol. Chem. 262, 8884-8888; Di Virgilio, F.、Meyer, B.C.、Greenberg, S. 和 Silverstein, S.C. (1988) J. Cell Biol. 106, 657-666)。从培养介质中去除 ATP 后，ATP 透化的 Ca2+i 耗尽的巨噬细胞恢复了接近正常的质膜电位，该电位在低 [Ca2+]i 下培养 2-4 小时后缓慢去极化。在 ATP 处理细胞和 quin2 负载细胞中，质膜电位去极化与质膜对低分子量水溶质（如曙红黄 (Mr 692)、溴化乙锭 (Mr 394) 和荧光黄 (Mr 463)）的通透性增加同时发生。这种质膜通透性的增加并不伴随孵育长达 4 小时的细胞质标记物乳酸脱氢酶的释放，并且可能是 Ca2+i 消耗的特定影响，因为它不是由以下原因引起的：（i）巨噬细胞与细胞外 EGTA 的单纯孵育，即在接近正常的 [Ca2+]i； (ii) 将二亚乙基三胺五乙酸加载到细胞质中，二亚乙基三胺五乙酸是一种对 Ca2+ 具有低亲和力的特定重金属螯合剂。用蛋白激酶 C 的直接（佛波醇 12-肉豆蔻酸酯 13-乙酸酯）或间接（血小板活化因子）激活剂处理 Ca2+i 耗尽的细胞可防止质膜通透性的增加。蛋白激酶 C 的下调使 Ca2+i 耗尽的巨噬细胞对佛波醇 12-肉豆蔻酸酯 13-乙酸酯的保护作用产生抵抗。该报告表明 Ca2+i 和可能的蛋白激酶 C 在调节质膜对低分子量水溶质的渗透性中的作用。
Cytoplasmic free Ca2+ (Ca2+i) was chelated to 10-20 nM in the macrophage cell line J774 either by incubation with quin2 acetoxymethyl ester in the absence of external Ca2+ (Di Virgilio, F., Lew, P.D., and Pozzan, T. (1984) Nature 310, 691-693) or by loading [ethyl-enebis(oxyethylenenitrilo)]tetraacetic acid (EGTA) into the cytoplasm via reversible permeabilization of the plasma membrane with extracellular ATP (Steinberg, T.H., Newman, A.S., Swanson, J.A., and Silverstein, SS.C. (1987) J. Biol. Chem. 262, 8884-8888; Di Virgilio, F., Meyer, B.C., Greenberg, S., and Silverstein, S.C. (1988) J. Cell Biol. 106, 657-666). After removal of ATP from the incubation medium, ATP-permeabilized Ca2+i-depleted macrophages recovered a near-normal plasma membrane potential which slowly depolarized over a 2-4 h incubation at low [Ca2+]i. In both ATP-treated and quin2-loaded cells, depolarization of plasma membrane potential was paralleled by an increase in plasma membrane permeability to low molecular weight aqueous solutes such as eosin yellowish (Mr 692), ethidium bromide (Mr 394), and lucifer yellow (Mr 463). This increased plasma membrane permeability was not accompanied by release of the cytoplasmic marker lactic dehydrogenase for incubations up to 4 h and was likely a specific effect of Ca2+i depletion since it was not caused by: (i) the mere incubation of macrophages with extracellular EGTA, i.e. at near-normal [Ca2+]i; and (ii) loading into the cytoplasm of diethylenetriaminepentaacetic acid, a specific chelator of heavy metals with low affinity for Ca2+. Treatment of Ca2+i-depleted cells with direct (phorbol 12-myristate 13-acetate) or indirect (platelet-activating factor) activators of protein kinase C prevented the increase in plasma membrane permeability. Down-regulation of protein kinase C rendered Ca2+i-depleted macrophages refractory to the protective effect of phorbol 12-myristate 13-acetate. This report suggests a role for Ca2+i and possibly protein kinase C in the regulation of plasma membrane permeability to low molecular weight aqueous solutes.