Beta-2 adrenergic receptor

In medicine and physiology, beta-2 adrenergic receptors, or β-2 adrenergic receptors, are adrenergic receptors that are a "subclass of beta-adrenergic receptors (receptors, adrenergic, beta). Beta-2 Adrenergic receptors are more sensitive to epinephrine than to norepinephrine and have a high affinity for the agonist terbutaline. They are widespread, with clinically important roles in skeletal muscle, liver, and vascular, bronchial, gastrointestinal, and genitourinary smooth muscle." Their functions include vasodilation.

After binding, signal transduction activates the second messenger systems adenyl cyclase-cyclic AMP primarily and also cyclic GMP which then activates protein kinases.

Adrenergic beta-agonists, such as terbutaline, are used to treat asthma by preventing bronchoconstriction.