Nitric Oxide/cGMP-Independent Vasorelaxation Enhanced by L-Arginine / 대한흉부외과학회지
The Korean Journal of Thoracic and Cardiovascular Surgery
;
: 102-107, 1998.
Artigo
em Coreano
| WPRIM
| ID: wpr-64721
ABSTRACT
It has not been clear whether L-arginine plays solely a role contributing to vascular nitric oxide (NO) synthesis. To investigate the mechanisms by which L-arginine induces vasorelaxation, effects of L-arginine on the isometric tension, and tissue NOx and cyclic guanosine monophosphate (cGMP) contents were examined in the isolated rat thoracic aorta. L-Arginine induced a dose-dependent relaxation of aortic rings only with intact endothelium only. The vasorelaxation response to low concentrations of L-arginine was abolished by the pretreatment with NG-nitro-L-arginine methyl ester (L-NAME, 10-4 mol/L), whereas the relaxation caused by higher concentrations L-arginine (10-5-10-3 mol/L) was maintained and even more pronounced in the presence of L-NAME. L-Arginine did not affect the vascular tension precontracted with KCl. The vascular tissue contents of NOx/cGMP were not significantly affected by L-arginine, while they were decreased by L-NAME. L-Arginine could not completely recover the NOx/cGMP decreased by L-NAME. Methylene blue only partially antagonized the relaxation response to L-arginine. Indomethacin did not affect the L-arginine-induced vasorelaxation, whereas ouabain markedly attenuated the relaxation. It is suggested that L-arginine induces vasorelaxation not only through its contribution to NO synthesis, but also through enhancing another endothelium-dependent mechanism which is NO/cGMP-independent and cyclooxygenase- independent.
Texto completo:
DisponíveL
Índice:
WPRIM (Pacífico Ocidental)
Assunto principal:
Aorta
/
Aorta Torácica
/
Ouabaína
/
Arginina
/
Relaxamento
/
Vasodilatação
/
Vasodilatadores
/
Indometacina
/
Guanosina Monofosfato
/
NG-Nitroarginina Metil Éster
Limite:
Animais
Idioma:
Coreano
Revista:
The Korean Journal of Thoracic and Cardiovascular Surgery
Ano de publicação:
1998
Tipo de documento:
Artigo
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