title: [Effects of a nitric oxide donor, the substratum of NO-synthase, and an inhibitor of NO-synthase on the ROS-generation activity of phagocytes in the course of ascites tumor growth].
abstract: Experiments in vitro were performed to investigate the effects of the nitric oxide donor (SNP), the substratum of NO-synthase (L-arginine), and the inhibitor of NO-synthase (nitroarginine) on the ROS-generating activity of blood plasma polymorphonuclear leucocytes and ascitic fluid macrophages isolated at different times of tumor (Zaidel hepatoma) growth in animal organism. It was found that in the initial period of tumor growth the nitric oxide donor at a concentration of 8 x 10(-5) M reduced the potential ROS-generating activity of macrophages by 38.5 +/- 9.0% and that of polymorphic-nuclear leucocytes of plasma by 27.6 +/- 7.0 %. However, the dynamics of this process during tumor growth was conservative: variations in the production of ROS by phagocytes were 10 +/- 3.0%. L-arginine induced a decrease in the ROS-generating activity of granulocytes and mononucleares by 25-30%. This fact points to an inducible inhibiting effect of NO-synthase on the ROS-generating activity of NADPH-oxidase in the course of tumor growth. The inhibitor of NO-synthase, nitroarginine, produced a monotonous increase in the ROS-generating activity of phagocytes isolated from the tumor at different periods of its growth. The use NO-synthase inhibitors for increasing ROS levels in the region of tumor growth may favor the suppression of tumor cell growth in vivo.
authors.forename: A A
authors.initials: AA
authors.lastname: Naumov
authors.forename: M M
authors.initials: MM
authors.lastname: Potselueva
mesh_terms: D000818:Animals; D001120:Arginine / Q000378:metabolism / Q000494:pharmacology; D001201:Ascites; D008113:Liver Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D008114:Liver Neoplasms, Experimental / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D008264:Macrophages / Q000187:drug effects; D008297:Male; D019255:NADPH Oxidases / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects; D009569:Nitric Oxide / Q000378:metabolism; D020030:Nitric Oxide Donors / Q000378:metabolism / Q000494:pharmacology; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000378:metabolism; D019335:Nitroarginine / Q000494:pharmacology / Q000627:therapeutic use; D009599:Nitroprusside / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D026361:Reactive Nitrogen Species / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D020030:Nitric Oxide Donors; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species; D009599:Nitroprusside; D019335:Nitroarginine; D009569:Nitric Oxide; D001120:Arginine; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D019255:NADPH Oxidases