KINETIC ANALYSES OF CALCIUM MOVEMENTS IN HELA CELL CULTURES .2. CALCIUM EFFLUX
KINETIC ANALYSES OF CALCIUM MOVEMENTS IN HELA CELL CULTURES .2. CALCIUM EFFLUX
复制标题
DOI：
10.1085/jgp.53.1.57
复制
发表时间：
1969-01-01
影响因子：
3.8
通讯作者：
BORLE, AB
中科院分区：
文献类型：
--
作者：
BORLE, AB
在单层 HeLa 细胞中研究了钙流出。通过连续冲洗在开放系统中研究交换的快速相。其半衰期为 1.58 分钟，实际上与之前发现的钙流入快相 1.54 分钟相同。这表明流出的快速成分代表了来自细胞外区室的钙交换，可能来自与细胞膜表面结合的钙。二硝基苯酚 (DNP) 和碘乙酸盐 (IAA) 不会抑制钙从该室流出。在封闭的三室系统中研究了钙交换的慢相。在这些条件下测量的钙流出半衰期几乎与之前在钙流入研究中获得的半衰期相同：分别为 33.0 和 37.0 分钟。这个缓慢的隔室可能是细胞内可交换钙池。 DNP 和 IAA 抑制钙从该隔室流出，将半衰期从 33 分钟分别延长至 55.0 和 216 分钟。这表明钙从细胞中排出是一个活跃的过程。由于钙流入不受代谢抑制剂的影响，因此细胞钙浓度如在这些条件下预测的那样增加。降低温度也会显着抑制钙流出。
Calcium efflux was studied in monolayers of HeLa cells. The fast phase of exchange was studied in an open system by continuous washout. Its half-time was 1.58 min which is practically identical to the fast phase of calcium influx previously found to be 1.54 min. This suggests that the fast component of efflux represents calcium exchange from an extracellular compartment probably from calcium bound to the cell membrane surface. Dinitrophenol (DNP) and iodoacetate (IAA) do not inhibit calcium efflux from this compartment. The slow phase of calcium exchange was studied in a closed three compartment system. The half-time of calcium efflux measured under these conditions is almost identical to that obtained previously in studies of calcium influx: 33.0 and 37.0 min, respectively. This slow compartment is likely to be the intracellular exchangeable calcium pool. DNP and IAA inhibit calcium efflux from this compartment, lengthening the half-time from 33 min to 55.0 and 216 min, respectively. This suggests that calcium extrusion from the cell is an active process. Since calcium influx is not affected by metabolic inhibitors, the cellular calcium concentration increases as would be predicted under these conditions. Calcium efflux is also markedly depressed by lowering the temperature.