Evidence that an atypical beta-adrenoceptor mediates the prejunctional inhibition of non-adrenergic non-cholinergic contraction in guinea-pig bronchi.
Eur J Pharmacol
; 218(1): 187-90, 1992 Jul 21.
Article
en En
| MEDLINE
| ID: mdl-1327825
We investigated the effect of the putative beta 3 agonist BRL 35135 on non-adrenergic non-cholinergic (NANC) contractions in guinea-pig bronchial strips. BRL 35135 (10(-9) to 10(-6) M) did not alter the baseline tension but reduced NANC contractions induced by electrical field stimulation (EFS) in a concentration-dependent fashion without having a significant effect on the contraction induced by substance P (10(-6) M). BRL 35135 (10(-6) M) also reduced the contraction induced by capsaicin (10(-7) M). Likewise, BRL 37344 (10(-9) to 10(-6) M) reduced NANC contractions induced by EFS in a concentration-dependent fashion. While BRL 37344 up to concentrations of 10(-8) M did not alter the contraction induced by SP (10(-6) M), BRL 37344 (10(-8) M) significantly inhibited NANC contractions induced by EFS and capsaicin (10(-7) M), (P less than 0.01). The inhibitory effect of BRL 35135 (10(-6) M) on NANC contractions induced by EFS was not significantly altered by the non-selective beta-adrenoceptor antagonists, propranolol and pindolol (P greater than 0.10), by the beta 1-selective antagonists, atenolol and metoprolol (P greater than 0.20) (10(-8) to 10(-6) M), or by the alpha-adrenoceptor antagonist, phentolamine (10(-7) to 10(-5) M) (P greater than 0.50). These results suggest that beta 3 agonists exert a prejunctional inhibitory action on NANC contractions.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Broncoconstricción
/
Receptores Adrenérgicos beta
Límite:
Animals
Idioma:
En
Revista:
Eur J Pharmacol
Año:
1992
Tipo del documento:
Article
País de afiliación:
Japón
Pais de publicación:
Países Bajos