Nitric oxide, an important regulator of perfusion-contraction matching in conscious pigs.
Am J Physiol Heart Circ Physiol
; 279(1): H451-6, 2000 Jul.
Article
em En
| MEDLINE
| ID: mdl-10899086
ABSTRACT
We examined whether nitric oxide (NO) inhibition during moderate reduction in coronary blood flow (CBF) would affect perfusion-contraction matching. Coronary stenosis (CS) was induced in conscious pigs, which resulted in a stable 39 +/- 1% reduction in CBF for 1.5 h. Ischemic zone wall thickening (IZWT) decreased by an average of 56 +/- 2% during CS from 2.7 +/- 0.2 mm. After reperfusion, myocardial stunning was observed, but this recovered without evidence of necrosis. After recovery and subsequent administration of systemic NO synthase inhibition (N(omega)-nitro-L-arginine, 25 mg. kg(-1). day(-1) x 3 days), CS for 1.5 h reduced CBF similarly but decreased IZWT significantly more, P < 0.05, by 89 +/- 5%. Myocardial stunning, i.e., the decrease in IZWT at 12 h post-CS, was more severe (-65 +/- 5% vs. -21 +/- 3%), P < 0.05. Furthermore, CS during NO synthase inhibition resulted in multifocal subendocardial areas of necrosis in the area at risk. These data suggest that in the intact, conscious pig, NO inhibition prevents perfusion-contraction matching, resulting in intensification of post-ischemic stunning and development of subendocardial necrosis.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Isquemia Miocárdica
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Miocárdio Atordoado
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Nitroarginina
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Circulação Coronária
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Hemodinâmica
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Contração Miocárdica
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Óxido Nítrico
Limite:
Animals
Idioma:
En
Revista:
Am J Physiol Heart Circ Physiol
Ano de publicação:
2000
Tipo de documento:
Article