Purpose: To compare the cardiovascular and sympathetic effects of a new ultra-short-acting, highly cardioselective beta- blocker, landiolol, with esmolol, using an in vivo rabbit model.
Methods: Different bolus doses of landiolol (0.3, 1.0, 3.0 and 10.0 mg*kg(-1)) or esmolol (0.5, 1.5 and 5.0 mg*kg(-1)) were given intravenously, and the effects on heart rate (HR) mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA) were compared.
Results: Both landiolol and esmolol produced a dose-dependent decrease in HR. The maximum percent reductions of HR were similar with landiolol 3 mg*kg(-1) and esmolol 5 mg*kg(-1) (-14.0 +/- 0.9% and -13.9 +/- 1.4%, mean +/- SE, respectively). HR decreased more rapidly with landiolol than with esmolol. Esmolol produced a dose-dependent decrease in MAP that was not observed with landiolol. The percent maximum reduction of MAP was -38.2 +/- 3.2% with esmolol 5 mg*kg(-1). RSNA increased in a dose-dependent fashion with esmolol, but no changes were noted with landiolol.
Conclusion: These results suggest that, in rabbits, landiolol has slightly more potent negative chronotropic action than esmolol with significantly less effects on blood pressure.