Possible involvement of nitric oxide synthase in oxidative stress-induced endothelial cell injury.
The purpose of this study was to characterize the protective effect of NG-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase, on oxidative stress-induced endothelial cell injury. Intracellular oxidative stress was induced by 1-chloro-2,4-dinitrobenzene, a glutathione (GSH) depleting agent, and the leakage of intracellular lactate dehydrogenase was measured as a marker of cell injury. Addition of 1-chloro-2,4-dinitrobenzene (100-500 microM) induced leakage of lactate dehydrogenase from endothelial cells, and the leakage of lactate dehydrogenase was strongly attenuated by L-NAME, but not by NG-methyl-L-arginine, also an inhibitor of nitric oxide synthase. However, cell injury induced by the Ca2+ ionophore ionomycin was not affected by L-NAME or NG-methyl-L-arginine. Moreover, neither L-NAME nor NG-methyl-L-arginine affected GSH depleting agent-induced or H2O2-induced cell injury in a rat foetal lung fibroblast cell line which lacks nitric oxide synthase. These results suggest that the protective effect of L-NAME is likely to be related to nitric oxide synthase, while the inhibition of nitric oxide production may not be involved in the protective effect of L-NAME, since NG-methyl-L-arginine did not affect endothelial cell injury.
Ishii
M
M
Department of Clinical Pharmacy, School of Pharmaceutical Sciences, Showa University, Tokyo, Japan.
Yamamoto
T
T
Shimizu
S
S
Sano
A
A
Momose
K
K
Kuroiwa
Y
Y
D000818:Animals; D001011:Aorta / Q000166:cytology; D002417:Cattle; D004137:Dinitrochlorobenzene / Q000009:adverse effects; D004730:Endothelium, Vascular / Q000201:enzymology / Q000293:injuries*; D005347:Fibroblasts / Q000201:enzymology; D066298:In Vitro Techniques; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats
D004137:Dinitrochlorobenzene; D007770:L-Lactate Dehydrogenase; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester