What is Receptor, Adrenergic, beta-2?

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.