title: [DNA damage and changes of antioxidative enzymes in chronic benzene poisoning mice].
abstract: OBJECTIVE
  To study the damage effect of benzene on DNA and its mechanism and the changes of antioxidative enzymes in vivo.
  
  
  METHODS
  DNA break in bone marrow cells and peripheral blood lymphocytes of mice exposed to benzene by 4 h static inhalation per day at different concentrations for two months were analyzed with single cell gel electrophoresis (SCGE). Meanwhile, the activity of SOD, GSH-Px and the level of MDA in liver, spleen and brain were detected.
  
  
  RESULTS
  In low and high dosage groups, the rate of DNA migration of bone marrow cells (83.56% +/- 10.28%, 92.54% +/- 15.93%) and peripheral blood lymphocytes (41.27% +/- 6.03%, 65.79% +/- 11.62%) were higher than those in control (4.13% +/- 0.52% and 2.21% +/- 0.31% respectively, P<0.05]. The activity of SOD in liver [(754.33 +/- 116.30), (694.26 +/- 116.30) U/mg pro] and GSH-Px [(22.52 +/- 3.31), (18.56 +/- 4.97) U/mg pro] were lower than those in control [(999.92 +/- 188.24) and (35.31 +/- 6.63) U/mg pro respectively, P<0.05, P<0.01]. But there was no significant difference between the two dosage groups. The activity of GSH-Px in spleen of both groups [(31.38 +/- 2.71), (25.30 +/- 7.44) U/mg pro] were lower than that of control [(37.11 +/- 3.42) U/mg pro, P<0.05] and there was significant difference between the two dosage groups. The activity of GSH-Px in brain of both groups [(5.70 +/- 0.84), (5.24 +/- 1.19) U/mg pro, P<0.05] were lower than that of control [(7.10 +/- 0.46) U/mg pro, P<0.05], but there was no significant difference between the two dosage groups. The level of MDA in brain of high dosage group [(3.99 +/- 1.15) nmol/mg pro] was higher than that of control [(2.58 +/- 0.53) nmol/mg pro, P<0.05].
  
  
  CONCLUSIONS
  Chronic benzene poisoning may result in DNA break in bone marrow cells and peripheral blood lymphocytes and decrease in the activity of antioxidative enzymes.
authors.affiliation: The Public Health College of Harbin Medical University, Harbin 150001, China.
authors.forename: Hong-zhi
authors.initials: HZ
authors.lastname: Pan
authors.forename: Li-xin
authors.initials: LX
authors.lastname: Na
authors.forename: Ling
authors.initials: L
authors.lastname: Tao
mesh_terms: D000818:Animals; D001554:Benzene / Q000506:poisoning*; D002908:Chronic Disease; D004249:DNA Damage; D005979:Glutathione Peroxidase / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000032:analysis; D051379:Mice; D013482:Superoxide Dismutase / Q000378:metabolism*
chemical_list: D008315:Malondialdehyde; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D001554:Benzene