کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2535966 1559137 2007 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Cooling augments vasoconstriction mediated by 5-HT1 and α2-adrenoceptors in the isolated equine digital vein: involvement of Rho kinase
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب سلولی و مولکولی
پیش نمایش صفحه اول مقاله
Cooling augments vasoconstriction mediated by 5-HT1 and α2-adrenoceptors in the isolated equine digital vein: involvement of Rho kinase
چکیده انگلیسی

The vasculature of the equine digit fulfils an important role in thermoregulation. In other species, it has been found that cooling may enhance the response of cutaneous vessels to 5-hydroxytryptamine (5-HT) and α2-adrenoceptor agonists. Translocation of α2-adrenoceptors to the smooth muscle cell membrane, mediated by Rho kinase, is thought to be involved in the cooling-enhanced response in mouse tail arteries. However, little is known about the effect of cooling on 5-HT receptor function. The present investigation compared the response of 5-bromo-6-(2-imidazolin-2-ylamino) quinoxaline (UK14304:1 nM to 30 μM), methoxamine (0.1 nM to 30 μM; in the presence of yohimbine 0.1 μM), 5-carboxamidotryptamine (5-CT; 0.1 nM to 10 μM) and α-methyl 5-HT (0.1 nM to 10 μM) in the isolated equine digital vein at 30 °C and 22 °C. The effect of the Rho kinase inhibitor, fasudil (1 μM), and the recovery of the response after the irreversible blockade of surface receptors with phenoxybenzamine (10 μM) or 2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline (EEDQ;10 μM), was established. Moderate cooling significantly increased the maximum response to α-methyl 5-HT, 5-CT and UK14304 and shifted their response curves to the left. Cooling also augmented the phenoxybenzamine- and EEDQ-resistant response to UK14304 and 5-CT, respectively. Fasudil had no effect on the contractile response at 30 °C, but completely abrogated the effect of cooling on the response to 5-CT and UK14304. The response to methoxamine was not significantly affected by cooling. These results suggest that Rho kinase plays an important role in the cooling-enhanced response mediated by 5-HT1B/D receptors and α2-adrenoceptors. The exact mechanism by which Rho/Rho kinase enhances the functional responses mediated by these receptors in these vessels has yet to be determined.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Journal of Pharmacology - Volume 569, Issue 3, 27 August 2007, Pages 212–221
نویسندگان
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