L-arginine ameliorates experimental autoimmune myocarditis by maintaining extracellular matrix and reducing cytotoxic activity of lymphocytes.
It was previously shown that administration of the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) aggravated murine viral myocarditis by increasing myocardial virus titres. Experimental autoimmune myocarditis in mice and rats mimics human fulminant myocarditis. The effects of L-arginine, a precursor of nitric oxide, upon heart failure in experimental autoimmune myocarditis were evaluated. Dietary L-arginine (L-arginine group) and L-arginine plus N(G)-nitro-L-arginine methyl ester (L-arginine + l-NAME group) were administered to C57BL/6 mice immunized with porcine cardiac myosin over 3 weeks. An untreated myocarditis group was prepared. Cardiac damage was less in the L-arginine group compared with the other two groups, as was incidence of heart failure. In addition, extracellular matrix change was less prominent in the L-arginine group. Plasma concentrations of nitric oxide were elevated in the L-arginine group. Cytotoxic activities of lymphocytes were lower in L-arginine group than in other two groups. L-arginine treatment may be effective in preventing the development of heart failure in experimental myocarditis by maintaining extracellular matrix and reducing the cytotoxic activity of lymphocytes.
Okabe
Taka-aki
TA
Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Hattori
Miki
M
Yuan
Zuyi
Z
Kishimoto
Chiharu
C
D000818:Animals; D001120:Arginine / Q000627:therapeutic use*; D001327:Autoimmune Diseases / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology; D003601:Cytotoxicity Tests, Immunologic; D005109:Extracellular Matrix / Q000473:pathology; D008214:Lymphocytes / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D023421:Models, Animal; D009205:Myocarditis / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology; D009206:Myocardium / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D009218:Myosins; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000037:antagonists & inhibitors / Q000097:blood; D013552:Swine
D009569:Nitric Oxide; D001120:Arginine; D009218:Myosins; D019331:NG-Nitroarginine Methyl Ester