Evidence for the role of a1D- and a 1A-adrenoceptors in contraction of the rat mesenteric artery
Por:
Arévalo-León L.E., Gallardo-Ortíz I.A., Urquiza-Marín H., Villalobos-Molina R.
Publicada:
1 ene 2003
Resumen:
We investigated the ?1-adrenoceptor subtype(s) involved in contraction of the isolated rat mesenteric artery by the use of the agonists noradrenaline (NA), phenylephrine (PHE), oxymetazoline (OXY), and methoxamine (MET), the competitive antagonists 8-(2-(4-(2-methoxyphenyl)-1-piperazinyl) ethyl)-8-azaspiro(4.5)decane-7,9-dione dihydrochloride (BMY 7378) and 5-methylurapidil, and the alkylating agent chloroethylclonidine (CEC). Agonists showed the potency order NA?PHE>OXY>MET; pA2 values for 5-methylurapidil and BMY 7378 were 7.74±0.11 and 8.72±0.28, respectively, while Schild slopes were not different than unity; ? 1-adrenoceptor alkylation with CEC showed a drastic decrease in maximal agonists-induced contraction and a shift to the right of about 46-, 122-, 2-, and 15-fold higher than controls for NA, PHE, OXY, and MET, respectively. Data suggest that ?1D-adrenoceptors predominate for contraction in mesenteric artery of the Wistar rat, with a second population of ?1A-adrenoceptors responding at high agonist concentrations. © 2002 Elsevier Science Inc. All rights reserved.
Filiaciones:
Arévalo-León L.E.:
Inst. de Invest. Quimico Biol., Univ. Michoacana S. Nicolas Hidalgo, Morelia, Mich., Mexico
Gallardo-Ortíz I.A.:
Depto. de Farmacobiología, Ctro. Invest. Estud. Avanzados-Sede, Calz. Tenorios #235, Mexico D.F. 14330, Mexico
Urquiza-Marín H.:
Inst. de Invest. Quimico Biol., Univ. Michoacana S. Nicolas Hidalgo, Morelia, Mich., Mexico
Villalobos-Molina R.:
Inst. de Invest. Quimico Biol., Univ. Michoacana S. Nicolas Hidalgo, Morelia, Mich., Mexico
Depto. de Farmacobiología, Ctro. Invest. Estud. Avanzados-Sede, Calz. Tenorios #235, Mexico D.F. 14330, Mexico
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