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. 1985 Oct;86(2):335–339. doi: 10.1111/j.1476-5381.1985.tb08901.x

No evidence for differences between pre- and post-junctional alpha 2-adrenoceptors.

J R Docherty, L Hyland
PMCID: PMC1916697  PMID: 2864971

Abstract

We have examined the pre- and post-junctional effects of a series of alpha-adrenoceptor agonists and antagonists at alpha 2-adrenoceptors in the pithed rat preparation and the human isolated saphenous vein. In the pithed rat, there was no difference in relative agonist and antagonist potencies between pre- and post-junctional alpha 2-adrenoceptors but the absolute potencies of antagonists differed: antagonists were more potent prejunctionally. In the human saphenous vein, the alpha 2-adrenoceptor antagonist yohimbine had pre- and post-junctional actions over the same concentration range. We have no evidence to suggest differences between pre- and post-junctional alpha 2-adrenoceptors: differences in absolute antagonist potencies in the pithed rat may be due to non-equilibrium conditions.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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