EPR evidence for nitric oxide production from guanidino nitrogens of L-arginine in animal tissues in vivo.
Biochim Biophys Acta
; 1099(3): 233-7, 1992 Mar 13.
Article
em En
| MEDLINE
| ID: mdl-1312861
ABSTRACT
Administration of Fe(2+)-citrate complex (50 mg/kg of FeSO4 or FeCl2 plus 250 mg/kg of sodium citrate) subcutaneously in the thigh or Escherichia coli lipopolysaccharide (LPS, 1 mg/kg) intraperitoneally, (i.p.) to mice induced NO formation in the livers in vivo at the rate of 0.2-0.3 micrograms/g wet tissue per 0.5 h. The NO synthesized was specifically trapped with Fe(2+)-diethyldithiocarbamate complex (FeDETC2), formed from endogenous iron and diethyldithiocarbamate (DETC) administered i.p. 0.5 h before decapitation of the animals. NO bound with this trap resulted in the formation of a paramagnetic mononitrosyl iron complex with DETC (NO-FeDETC2), characterized by an EPR signal at g perpendicular = 2.035, g parallel = 2.02 with triplet hyperfine structure (HFS) at g perpendicular. This allowed quantification of the amount of NO formed in the livers. An inhibitor of enzymatic NO synthesis from L-arginine, NG-nitro-L-arginine (NNLA, 50 mg/kg) attenuated the NO synthesis in vivo. L-Arginine (500 mg/kg) reversed this effect. Injection of L-[guanidineimino-15N2]arginine combined with Fe(2+)-citrate or LPS led to the formation of the EPR signal of NO-FeDETC2 characterized by a doublet HFS at g perpendicular, demonstrating that the NO originates from the guanidino nitrogens of L-arginine in vivo.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arginina
/
Fígado
/
Óxido Nítrico
Limite:
Animals
Idioma:
En
Revista:
Biochim Biophys Acta
Ano de publicação:
1992
Tipo de documento:
Article
País de afiliação:
Federação Russa