OBJECTIVETo study the effect of H2O2 on the morphological pattern,vitality,proliferation,cycle period of rabbit intervertebral disc nucleus pulposus cells.

METHODSTen New Zealand white rabbits (2 to 3 kg, female) were used for isolating nucleus pulposus cells under sterilized condition. The culture solution with 15% FBS and DMEM/F12 (1:1) was applied for cell cultivation. After 90% cell fusion, the first generation was obtain and stimulated by H2O2 with different concentrations of 0 micromol/L (control group), 130 micromol/L,216 p.mol/L,360 Ipmol/L, 600 micromol/L,and 1000 micromol/L.

RESULTSCompared with the control group, there was little difference of the biological property (P>0.05) in 130 micromol/L and 216 micromol/L H202-treated groups. When the concentration of H2O2 attained 360 micromol/L, 600 micromol/L, and 1 000 micromol/L, the cells suffered aging,with increased cell vacuoles,decreased proliferation,and aging:related increase of 13-galactosidase dyeing. The cell cycle of many nucleus pulposus cells was blocked in G1 stage other than entering S stage. With increasing H2O2 concentrations, the aging degree was increased.

CONCLUSIONA certain concentration of H202 could induce early aging of nucleus pulposus cells,resulting in biological abnormalities of these cells.