title: [Changes in Ca(2+)concentration and caspase-3 expression and their relationship in Raji cells exposed to electromagnetic radiation].
abstract: OBJECTIVE
  To study the effects of electromagnetic pulse (EMP), S-band high power microwave (S-HPM), and X-band high power microwave (X-HPM) on the Ca(2+) concentration and caspase-3 expression in Raji cells and the relationship between Ca(2+) concentration and caspase-3 expression, and to investigate the regulatory mechanism of electromagnetic radiation damage.
  
  
  METHODS
  Raji cells were cultured conventionally. Some cells were irradiated by EMP, S-HPM, and X-HPM in the logarithmic growth phase for 6 hours and then collected; others received sham irradiation as a control. The Ca(2+) concentration in the cells was measured by laser scanning confocal microscope; the caspase-3 expression in the cells was evaluated by Western blot.
  
  
  RESULTS
  Compared with the control group (Ca(2+) fluorescence intensity = 43.08 ± 2.08; caspase-3 expression level = 0.444 ± 0.13), the EMP,S-HPM, and X-HPM groups had significantly increased Ca(2+) concentrations, with Ca(2+) fluorescence intensities of 69.56 ± 1.71, 50.06 ± 1.89, and 70.68 ± 1.59, respectively (P < 0.01), and had upregulated caspase-3 expression, with expression levels of 0.964 ± 0.12, 0.586 ± 0.16, and 0.970 ± 0.07, respectively (P < 0.01). Each of the EMP and X-HPM groups had significantly higher Ca(2+) fluorescence intensity and caspase-3 expression level than the S-HPM group (P < 0.01), but there were no significant differences between the EMP and X-HPM groups. The linear regression analysis showed that the caspase-3 expression was upregulated as the Ca(2+) concentration increased, with a positive correlation between them (P < 0.01).
  
  
  CONCLUSIONS
  EMP, S-HPM, and X-HPM cause damage probably by increasing the Ca(2+) concentration in cells and in turn inducing caspase-3 overexpression.
authors: Department of Pathology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China. wangweilv@yahoo.com.cn
authors: Wei
authors: W
authors: Wang
authors: Huan-xin
authors: HX
authors: Liu
authors: De-wen
authors: DW
authors: Wang
authors: Hong-yan
authors: HY
authors: Zuo
authors: Rui-yun
authors: RY
authors: Peng
mesh_terms: D002118:Calcium / Q000378:metabolism*; D053148:Caspase 3 / Q000378:metabolism*; D045744:Cell Line, Tumor; D060733:Electromagnetic Radiation; D006801:Humans
chemical_list: C505407:CASP3 protein, human; D053148:Caspase 3; D002118:Calcium