Inhibitory effect of fentanyl on phenylephrine-induced contraction of the rat aorta.
Yonsei Med J
; 50(3): 414-21, 2009 Jun 30.
Article
em En
| MEDLINE
| ID: mdl-19568605
ABSTRACT
PURPOSE:
Fentanyl was reported to inhibit the alpha(1)-adrenoceptor agonist-induced contraction. The goal of this in vitro study was to identify the alpha(1)-adrenoceptor subtype primarily involved in the fentanyl-induced attenuation of phenylephrine-induced contraction in isolated endothelium-denuded rat aorta. MATERIALS ANDMETHODS:
Aortic rings were suspended in order to record isometric tension. Concentration-response curves for phenylephrine (10(-9) to 10(-5) M) were generated in the presence or absence of one of the following drugs fentanyl (3 x 10(-7), 10(-6), 3 x10(-6) M), 5-methylurapidil (3 x10(-8), 10(-7), 3 x 10(-7) M), chloroethylclonidine (10(-5) M) and BMY 7378 (3 x 10(-9), 10(-8), 3 x 10(-8) M). Phenylephrine concentration-response curves were generated in the presence or absence of fentanyl in rings pretreated with either 3 x10(-9) M prazosin, 10(-9) M 5-methylurapidil or 3 x 10(-9) M BMY 7378.RESULTS:
Fentanyl (10(-6), 3 x 10(-6) M) attenuated phenylephrine-induced contraction in the rat aorta. 5-Methylurapidil and BMY 7378 produced a parallel rightward shift in the phenylephrine concentration-response curve. The pA(2) values for 5-methylurapidil and BMY 7378 were estimated to be 7.71 +/- 0.15 and 8.99 +/- 0.24, respectively. Fentanyl (10(-6) M) attenuated phenylephrine-induced contraction in rings pretreated with 10(-9) M 5-methylurapidil, but did not alter the rings when pretreated with 3 x 10(-9) M BMY 7378. Pretreatment of the rings with chloroethylclonidine showed a 72.9 +/- 2.3% reduction in phenylephrine-induced maximal contraction.CONCLUSION:
The results suggest that fentanyl attenuates phenylephrine-induced contraction by inhibiting the pathway involved in the alpha(1D)-adrenoceptor-mediated contraction of the rat aorta.Palavras-chave
Texto completo:
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Bases de dados:
MEDLINE
Assunto principal:
Aorta
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Fenilefrina
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Vasoconstrição
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Fentanila
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Agonistas alfa-Adrenérgicos
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Antagonistas Adrenérgicos alfa
Limite:
Animals
Idioma:
En
Revista:
Yonsei Med J
Ano de publicação:
2009
Tipo de documento:
Article