Relationship between the sympatholytic action of nebivolol and hypotension

Abstract

Nebivolol, a chemically novel β1-adrenoceptor antagonist, acutely lowers blood pressure in spontaneously hypertensive rats, anaesthetised nor-motensive dogs, and hypertensive patients. We have investigated the actions of dl-nebivolol in five conscious normotensive rabbits (sham, mean blood pressure (BP) of 82.2 ±; 4.1 mm Hg, mean ±; SEM) and four hypertensive rabbits (renal wrap hypertension) (wrap, mean BP of 117.6 ±; 1.5 mm Hg). Nebivolol (1 mg/kg i.v.) did not significantly lower the BP or heart rate in either group 30 min after injection. In the same rabbits, on another day, after autonomic blockade (mecamylamine), nebivolol (0.1, 0.3, and 1.0 mg/kg i.v.) right shifted the bolus i.v. iso..