Subtype classification of presynaptic alpha 2-adrenoceptors
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Updated: Nov 7, 2026

Brain Membrane Fractionation: An Ex Vivo Approach to Assess Subsynaptic Protein Localization
Published on: May 12, 2017
1Department of Receptor Pharmacology, Kabi Pharmacia Therapeutics, Stockholm, Sweden.
Abstract:
1. Presynaptic alpha 2-adrenoceptors in a few tissues have recently been pharmacologically classified in functional studies. 2. Autoreceptors are of alpha 2A-subtype in rabbit occipito-parietal cortex, rat cerebral cortex, vas deferens, submandibular gland, kidney, guinea-pig ileum submucosal arterioles and urethra. 3. Heteroreceptors are of alpha 2A-subtype in rat cerebral cortex, vas deferens, guinea-pig ileum submucosal plexus and Auerbach's plexus. 4. In rat atria autoreceptors have been shown to be of alpha 2B-subtype. 5. Classification is done mainly with alpha 2A-adrenoceptor-selective oxymetazoline, WB 4101 and BRL 44408, and the alpha 2B-adrenoceptor-selective prazosin, AR-C 239, chlorpromazine and BRL 41992. 6. With four alpha 2-adrenoceptor subtypes to consider, a larger number of subtype-selective compounds may have to be characterized in the classification in the many tissues, where presynaptic alpha 2-adrenoceptors are found.
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