Ratio Fluorescence Test Of [Ca～(2+)]_i Of K562 Cell During Proliferation And Lesion

As one of the most important information carriers, Ca2+ plays a crucial role in cell function. External signals make spatio-temporal changes of intracellular free Ca2+ concentration, and calcium signals come into being, which stimulates a series of inner cell affairs and fulfills cell physiological functions. Studies on the relationship between calcium signals and cell physiology ( especially tumor cell proliferation, cell lesion and apoptosis), and on the response of tumor cell [Ca2+]i to the physical factor (e.g. magnetic field, radial), are important to the tumor cell biology and to the biological effects of magnetic field academically and practically.In this study, [Ca2+]i of human tumor cell line K562 was tested using ratio fluorescence test. The changes of [Ca2+]i was researched in the process of cell proliferation, cell lesion and apoptosis. The effects of static magnetic field on [Ca2+]i was investigated. The main conclusions are as followed:1. The testing system of the ratio fluorescence microscopy was established and optimized, and the reliability of the testing system was also analyzed. The test result of the intracellular free Ca2+ concentration shows the significant differences among cell population.2. The cell cycle of K562 was synchronized, and the phase of the cell cycle changes of [Ca2+]i in K562 cell proliferation process were tested. The experimental results showed that [Ca2+]i kept at a relatively lower level in S-phase and fluctuated considerably in M-phase, which indicated the increase of [Ca2+]i could stimulate the startup and finish of the mitosis.3. Established the classical experimental model of apoptosis of HL-60 induced by taxol, and tested [Ca2+]i of HL-60 treated with taxol at different time and concentrations by ratio fluorescence test. The results of experiments showed that increasing of [Ca2+]i may be upstream signal of cell apoptosis.4. K562 cells were placed in 9mT static magnetic field, and measured the change of [Ca2+]i by ratio fluorescence test. The data of the change of [Ca2+]i in different cell cycle phase and the results of flow cytometer (FCM) showed that increasing of [Ca2+]i should be the death signal of K562 exposed in static magnetic field. The results of MTT assay revealed that static magnetic field could restrain the cell growth.