Alpha-2 adrenergic receptors mediate the catecholamine-induced inhibition of adenylate cyclase through the action of G proteins. The rank order of potency for agonists of this receptor is clonidine > norepinephrine > epinephrine = oxymetazoline > dopamine > p-tyramine = phenylephrine > serotonin > p-synephrine / p-octopamine. For antagonists, the rank order is yohimbine > chlorpromazine > phentolamine > mianserine > spiperone > prazosin > alprenolol > propanolol > pindolol. Interacts with RAB26 (PubMed:23105096). Interacts with PPP1R9B (PubMed:24114805). Interacts with GGA1, GGA2 and GGA3 (PubMed:27901063, PubMed:26811329). Interaction with RAB26, GGA1, GGA2 and GGA3 mediates transport from the Golgi to the cell membrane. A rare polymorphic frameshift in position 451 produces a protein of 545 residues. The disease is caused by variants affecting the gene represented in this entry. Belongs to the G-protein coupled receptor 1 family. Adrenergic receptor subfamily. ADRA2B sub-subfamily.