title: Generation of reactive oxygen species by polymorphonuclear leukocytes and its modulation by calcium ions during tumor growth.
abstract: The generation of reactive oxygen species (ROS) by polymorphonuclear leukocytes (PMNL) and the role of Ca2+ in regulating their activity during Zajdela hepatoma growth in the animal peritoneal cavity were studied. We found a marked increase in the ROS-generating activity of PMNL in circulating blood, the result of increases in both the specific activity of leukocytes and total number of PMNL in circulating blood. The ROS-generating activity of PMNL was substantially activated by Ca2+ ions and a calcium ionophore (ionomycin), but this effect virtually completely disappeared during tumor growth. Perhaps the high ROS-generating activity of PMNL and the lack of the sensitivity to extracellular Ca2+ during tumor growth in the organism are due to an accumulation of intracellular Ca2+ ions.
authors.affiliation: Institute of Theoretical and Experimental Biophysics, RAS, Pushchino, Moscow Region, Russian Federation.
authors.forename: A V
authors.initials: AV
authors.lastname: Pustovidko
authors.forename: M M
authors.initials: MM
authors.lastname: Potselueva
authors.forename: Y V
authors.initials: YV
authors.lastname: Evtodienko
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D015759:Ionomycin / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D007958:Leukocyte Count; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D008163:Luminescent Measurements; D008297:Male; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D007476:Ionophores; D017382:Reactive Oxygen Species; D015759:Ionomycin; D002118:Calcium