Figure 7. Schematic illustration indicating GRK2 (G protein‐coupled receptor kinase 2) is associated with ADRB1 (adrenergic receptor beta 1) internalization and cardiac hypertrophy.

A, In hypertension, ADRB1 is activated via interacting with circulating catecholamines, eg, epinephrine. GRK2 participates in the regulation of ADRB1 by triggering ADRB1 desensitization from G proteins complex and internalization, thus contributing to signal propagation. B, Paroxetine suppresses ADRB1 internalization via functioning as the GRK2 inhibitor, thus enhances the stabilization and activity of ADRB1 on the surface of cardiomyocytes. Therefore, catecholamines in circulation decreases and reduces the stimulation of cardiomyocytes resulting in alleviation of cardiac hypertrophy. ADRB1 indicates adrenergic receptors beta 1; and GRK2, G‐protein‐coupled receptor kinase 2.