Generation of reactive oxygen species by polymorphonuclear leukocytes and its modulation by calcium ions during tumor growth.
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.
Pustovidko
A V
AV
Institute of Theoretical and Experimental Biophysics, RAS, Pushchino, Moscow Region, Russian Federation.
Potselueva
M M
MM
Evtodienko
Y V
YV
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*
D007476:Ionophores; D017382:Reactive Oxygen Species; D015759:Ionomycin; D002118:Calcium