title: alpha 2-Adrenergic receptors inhibit catecholamine secretion from bovine adrenal medulla.
abstract: Catecholamine secretion evoked by carbamylcholine from isolated bovine adrenal medullary cells was inhibited by alpha 2-agonist, clonidine, in a dose-dependent manner with IC50 value of 2.8 X 10(-5) M. [3H]Clonidine bound to adrenal medullary membranes with high affinity and saturable characteristics. These results suggest that alpha 2-adrenergic receptors which exist on adrenal medullary cells have inhibitory effect on the secretion of catecholamine from the cells.
mesh_terms: D000313:Adrenal Medulla / Q000294:innervation* / Q000378:metabolism; D000818:Animals; D002395:Catecholamines / Q000378:metabolism*; D002417:Cattle; D003000:Clonidine / Q000378:metabolism / Q000494:pharmacology*; D046508:Culture Techniques; D004305:Dose-Response Relationship, Drug; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*; D013570:Synaptic Membranes / Q000378:metabolism
chemical_list: D002395:Catecholamines; D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D003000:Clonidine