Potassium release by alpha 2-adrenergic receptor stimulation of rat parotid acinar cells.
alpha-Adrenergic stimulation elicited a rapid release of K+ from dispersed parotid acinar cells in the presence of external Ca2+. A recent classification of alpha-adrenergic receptors proposed that alpha 1 receptors facilitate Ca2+ entry while alpha 2 receptors interact with adenylate cyclase. We tested this proposal by studying the ability of selective alpha-adrenergic antagonists to prevent epinephrine-induced release of K+ from parotid cells. The alpha 1 agents, WB 4101 and prazosin, were less potent than the alpha 2 antagonist yohimbine. These data suggest that alpha 2-adrenergic receptors in the parotid might facilitate the entry of Ca2+.
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D004837:Epinephrine / Q000494:pharmacology; D010306:Parotid Gland / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D051381:Rats; D013268:Stimulation, Chemical
D000316:Adrenergic alpha-Agonists; D011188:Potassium; D002118:Calcium; D004837:Epinephrine