Molecular Classification
G protein-coupled receptor, GPCR, Rhodopsin-like receptor
Other Names
ADRB2
Disease Roles
AsthmaChronic obstructive pulmonary diseaseConduction disorder

Beta2-Adrenergic Receptor Overview

The beta2-adrenergic receptor (β₂AR), also known as ADRB2, is a G protein-coupled receptor (GPCR) primarily binding epinephrine and, to a lesser extent, norepinephrine. Activation increases intracellular cAMP, leading to smooth muscle relaxation and bronchodilation. It's a key target for asthma and COPD treatment, but polymorphisms can affect drug response.

Mechanism of Action

Agonists bind to the β₂AR, activating adenylate cyclase via Gs proteins, leading to increased intracellular cAMP, resulting in smooth muscle relaxation and bronchodilation.

Biological Functions

Signal transduction
Smooth muscle relaxation
Bronchodilation
Regulation of intracellular cAMP levels

Disease Associations

Asthma
Chronic obstructive pulmonary disease
Conduction disorder
Preterm labour/delivery
Sleep-related breathing disorder
Obesity
Type 2 diabetes

Safety Considerations

  • Tachyphylaxis (desensitization)
  • Cardiovascular side effects (with some agonists)
  • Genetic polymorphisms can alter drug response

Interacting Drugs

Beta2AR agonists (e.g., albuterol, salmeterol)
Epinephrine
Norepinephrine