Use of transgenic (knockout) mice reveals a site distinct from the alpha2A-adrenoceptors for agmatine in the vas deferens.
Journal Title: Pharmacological Reports - Year 2009, Vol 61, Issue 2
Abstract
The inhibitory effect of agmatine on electrically induced contractions was studied in vas deferens of Adra 2a transgenic mice lacking alpha(2A)-adrenoceptors. Agmatine and clonidine caused a concentration-dependent inhibition of twitches. However, while agmatine showed a similar pIC(50) value in control and transgenic mice, the pIC(50) value for clonidine was about 30-fold lower in knockout mice. In both strains, yohimbine shifted the curve for clonidine, but not for agmatine, even when a 100-fold higher concentration of yohimbine was employed. Our results indicate that inhibition by agmatine in mouse vas deferens is not simply due to interactions with alpha(2)-adrenoceptors in our experimental conditions.
Authors and Affiliations
Wilson Santos, Lucia Garcez-do-Carmo, Eliane C da Silva, Ricardo de Pascual, Neide Jurkiewicz, Aron Jurkiewicz, Luis Gandía
Keywords
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