adrenergic receptor is the third subtype of β-adrenergic receptors. The genetic structure and pharmacological property of β 3-adrenergic receptor are markedly distinguished from β 1-and β 2-adrenergic receptor subtypes. Recently studies show that myocardial β 3-adrenergic receptor mediates negative inotropic effect through Gi-protein/NO/cGMP pathway, the expression of β 3-adrenergic receptor and negative inotropic effect mediated by β 3-adrenergic receptor are increased in heart failure. However, because of the low expression of β 3-adrenergic receptor in the heart, the actual pathophysiological significance of β 3-adrenergic receptor remains unknown.
