Differential effects of nitric oxide synthase inhibitors in rats
The Korean Journal of Physiology and Pharmacology
;
: 99-104, 2000.
Artigo
em Inglês
| WPRIM
| ID: wpr-728333
ABSTRACT
We investigated the action of NOS inhibitors on NOS in rats. Both of nitric oxide synthase inhibitors, NG-monomethyl-L-arginine (L-NMMA, 3 micrometer) or NG-nitro-L-arginine methylester (L-NAME, 30 micrometer), augmented phenylephrine (PE, 10-7 M)-induced contraction which was inhibited by acetylcholine (ACh) in rat thoracic aorta. This augmentation by L-NAME or L-NMMA was attenuated with the treatment of NO precursor, arginine. ACh, however, decreased the augmentation induced by L-NMMA, but not by L-NAME. Superoxide dismutase (SOD, 50 u/ml) potentiated an inhibitory effect of ACh on the PE (10-7 M)-induced contraction. It has been known that platelet activating factor itself induces iNOS. Platelet activating factor (PAF, 10-7 M) inhibited PE (10-7 M)-induced contraction. Pretreatment with L-NMMA (30 mM) or L-NAME (30 mM) significantly blocked the inhibitory action of PAF on PE-induced contraction. L-NMMA (100 mM) or L-NAME (100 mM) reduced nerve conduction velocity (NCV) relevant to nNOS in rat sciatic nerve. ACh attenuated the reduction of NCV by L-NMMA-, but not by L-NAME-induced reduction of NCV. These results suggest that L-NMMA and/or L-NAME have different action on three types of NOS in rats.
Texto completo:
DisponíveL
Índice:
WPRIM (Pacífico Ocidental)
Assunto principal:
Aorta Torácica
/
Fenilefrina
/
Arginina
/
Nervo Isquiático
/
Superóxido Dismutase
/
Fator de Ativação de Plaquetas
/
Acetilcolina
/
Óxido Nítrico Sintase
/
NG-Nitroarginina Metil Éster
/
Nitroarginina
Limite:
Animais
Idioma:
Inglês
Revista:
The Korean Journal of Physiology and Pharmacology
Ano de publicação:
2000
Tipo de documento:
Artigo
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