Beta2 Receptor

Overview

The Beta2 Adrenergic Receptor is a generally activating G-protein Coupled Receptor (GPCR) that binds the catecholamines norepinephrine and epinephrine.

Mechanism of Action

The Beta2 Receptor is a generally excitatory GPCR connected to the G_s G-protein. Briefly, following receptor stimulation, activated G_s leads to stimulation of adenylyl cyclase and the generation of cAMP which induces further downstream signaling responsible for the physiological actions of beta2 receptor activation.

Physiological Anatomy

Overview

The physiological actions of beta2 receptors center around relaxation of smooth muscle and modulation hepatic metabolism.

Bronchioles

Activation of Beta2 Receptors within bronchiolar sooth muscle leads to bronchodilation and thus reduced airflow resistance within the lung.

Uterus

Activation of Beta2 Receptors within the uterine smooth muscle leads to uterine relaxation

Vasculature

Activation of Beta2 Receptors within the vascular smooth muscle leads to vasodilation and thus reduced systemic vascular resistance.

Hepatic Glucose Metabolism

Activation of Beta2 Receptors within the liver stimulates glycogenolysis and gluconeogenesis, together increasing blood glucose concentration.