 Alpha-adrenergic receptor

An alpha-adrenergic receptor belongs to the alpha branch of adrenergic receptors, divided into alpha-1 adrenergic receptors and alpha-2 adrenergic receptors. The branches differ in their common G-protein coupling and intracellular signals. Grouping them as alpha receptors identifies related pharmacology, but does not mean that all produce the same response or activate the same messenger pathway. ^[ref]