influx fast 1.54min: infux slow 31min: efflux fast 1.58min: efflux slow 11min min
||HeLa cell line
||Borle AB. Kinetic analyses of calcium movements in HeLa cell cultures. II. Calcium efflux. J Gen Physiol. 1969 Jan53(1):57-69 abstract, p.57 bottom paragraph, p.62 1st paragraph under 'results' heading and p.63 table IPubMed ID5761873
||Abstract: "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."
||P.57 bottom paragraph: "[Investigators] have shown in a previous paper (ref 1) that a cell monolayer consisted of two unexchangeable pools of calcium and of two exchangeable compartments with markedly different time constants. [They] argued that the fast component with a half-time of 1.54 min was in all probability extracellular and that the slow component with a half-time of 31 min was likely to be the intracellular pool of calcium." P.62 1st paragraph under 'results' heading: "Washout Experiments: Fig. 2 shows the results of one representative study. The effluent activity was plotted semilogarithmically against time and the graphical analysis of the effluent curve shows that it can be resolved into two exponentially defined phases. In nine separate experiments the average rate constant of the fast phase was 0.460±0.032 min^-1 and that of the slower phase 0.071±0.008 min^-1 (Table I). The half-time for each phase was 1.58 and 11.0 min, respectively."