title: Peculiarities of DNA damage caused by exogenous nitric oxide combined with fractionated low dose ionizing radiation in normal and tumor cells.
abstract: The aim of this study was to investigate the reaction of normal and tumor cells to genotoxic effect of widespread environmental factors - exogenous nitric oxides and ionizing radiation.
  
  
  METHODS
  The animals were treated with NO (125 mg/m(3)) and low dose ionizing radiation (10 acute exposures with 0.1 Gy each). Genotoxicity was estimated in vivo in rats peripheral blood lymphocytes, bone marrow cells and tumor cells of Guerin carcinoma. DNA damages were assessed by alkaline single-cell gel electrophoresis.
  
  
  RESULTS
  Exogenous nitric oxides as well as irradiation caused significant increase of DNA damage in all types of investigated cells. The genotoxic effect increased in the order: peripheral blood lymphocytes < bone marrow cells < Guerin carcinoma cells. The greatest genotoxic effect was registered in Guerin carcinoma cells on terminal phase of tumor growth in rats exposed to NO and low dose ionizing radiation.
  
  
  CONCLUSIONS
  Long-term exposure to common environmental factors (exogenous nitric oxides and ionizing radiation) capable to induce DNA damage in different cells. Severity of the genotoxic effect depends on cell type and nature of impacting factors. NO caused more significant DNA damage than low dose ionizing radiation but the highest level of DNA damage was observed after their joint action. Obtained results confirm the real threat of cancer risk increase under combined action of common environmental factors of different nature.
authors: R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, NAS of Ukraine, Kyiv 03022, Ukraine.
authors: I I
authors: II
authors: Muzalov
authors: R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, NAS of Ukraine, Kyiv 03022, Ukraine.
authors: V M
authors: VM
authors: Mikhailenko
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D002277:Carcinoma / Q000139:chemically induced / Q000235:genetics*; D002478:Cells, Cultured; D004249:DNA Damage / Q000187:drug effects* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D004785:Environmental Pollutants / Q000633:toxicity; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D008297:Male; D009153:Mutagens / Q000633:toxicity*; D009381:Neoplasms, Radiation-Induced / Q000235:genetics*; D009569:Nitric Oxide / Q000633:toxicity*; D011839:Radiation, Ionizing; D051381:Rats; D014407:Tumor Cells, Cultured
chemical_list: D004785:Environmental Pollutants; D009153:Mutagens; D009569:Nitric Oxide