['Asymmetric dimethylarginine (ADMA), an endogenous nitric oxide synthase (NOS) inhibitor, induces endothelial dysfunction. Nebivolol, a highly selective β1-adrenergic receptor (AR) blocker, is the only beta-blocker known to induce vascular production of nitric oxide.', 'The present study was designed to evaluate the effect and mechanism of nebivolol on ADMA-induced vascular response in rat aorta in vitro.', 'In vitro, the effects of nebivolol and ADMA on resting tone or contraction induced by phenylephrine (PE, 10(-6\u2009)mol/L) and relaxation induced by acetylcholine (Ach, 10(-10)-10(-5\u2009)mol/L) were evaluated.', 'ADMA in a concentration-dependent manner increased the resting and PE-induced tone and reduced Ach-induced relaxation. Nebivolol inhibited the ADMA-induced enhancements in tone and reversed the effects of ADMA on Ach-induced relaxation. These effects of nebivolol were blocked by selective β3 receptor blocker cyanopindolol (1\u2009μM), but not by selective β2 receptor blocker butoxamine (50\u2009μM).'] Does nebivolol ameliorate asymmetric dimethylarginine-induced vascular response in rat aorta via β3 adrenoceptor-mediated mechanism?