[Change of Bcl-2, Bax proteins and mitochondrial membrane protein on nitric oxide induced apoptosis in HL-60 cells].

To investigate the possible mechanisms of nitric oxide(NO)-induced apoptosis in leukemia cell line HL-60,HL-60 cells in vitro were incubated with sodium nitroprusside (SNP),the in situ cell apoptosis quantitatively was assayed by TdT-mediated dUTP nick end labeling (TUNEL),the cell cycle DNA and proteins expression of Bcl-2,Bax,mitochondrial membrance protein (APO2.7) were analyzed by flow cytometry. The results showed that SNP induced HL-60 cell apoptosis in a dosage- and time- dependent manner. After exposure to SNP at the concentration of 1.0 mmol/L for 48 hours,the percentage of apoptosis HL-60 was (42.2±3.5)% for subG1 and (52.5±7.6)% for TUNEL respectively,and they are significantly higher than those in control and potassium ferricyanide (PFC) groups as same concentration. During the apoptosis process,it showed a decrease of Bcl-2 protein and an increase of Bax protein and mitochondrial membrance protein in HL-60 cell,proteins of Bcl-2,Bax and mitochondrial membrance were expressed in a dosage- and time-dependent manner too. In conclusion,during the process of SNP induced apoptosis in HL-60 cell,the expression of mitochondrial membrane protein was increased,Bcl-2 and Bax proteins may be important regulators.