[DNA damage in human peripheral blood lymphocyte caused by nickel and cadmium].
OBJECTIVE
To understand the different implication of various forms of DNA damage in genotoxicity of nickel and cadmium.


METHODS
Human peripheral lymphocyte was exposed to nickel chloride and cadmium chloride in vitro. Levels of DNA single-and double-strand breaks and DNA-protein crosslinks in human peripheral lymphocyte were determined with single cell gel electrophoresis (SCGE). Activity of poly (ADP-ribose) polymerase (PARP) was determined by [(3)H]-NAD incorporating method.


RESULTS
Levels of DNA single-and double-strand breaks and DNA-protein crosslinks in human peripheral lymphocyte treated with nickel and cadmium were significantly higher than those untreated, but dose-response relationship only showed in those treated with 0.10 - 10.00 micromol/L of nickel chloride and 0.16 - 20.00 micromol/L of cadmium. Low levels of the two kinds of metal (0.10 - 0.40 micromol/L of nickel and 0.16 micromol/L of cadmium) could induce the cleavage of DNA and activate PARP, and high levels of the two kinds of metal (2.00 - 10.00 micromol/L of nickel and 0.80 - 20.00 micromol/L of cadmium) could not induce the enzyme cleavage of DNA.


CONCLUSIONS
Formation and cleavage of DNA double strand and blockage of activation of PARP can play an important role in carcinogenesis and mutagenesis.
Cai
Y
Y
Laboratory Center, Shantou Bureau of Health Quarantine Service, Guangdong 515031.
Zhuang
Z
Z
D019256:Cadmium Chloride / Q000633:toxicity*; D020552:Comet Assay; D004249:DNA Damage / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects; D009532:Nickel / Q000633:toxicity*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism
C022838:nickel chloride; D009532:Nickel; D011065:Poly(ADP-ribose) Polymerases; D019256:Cadmium Chloride