Influence of Acebutolol and Metoprolol on Cardiac Output and Regional Blood Flow in Rats Publisher Pubmed



Abolfazl Mostafavi S^{1, 3} ; Lewanczuk RZ² ; Foster RT¹ Show Affiliations
Source: Biopharmaceutics and Drug Disposition Published:2000

Abstract

Beta-adrenoceptor blocking drugs are widely used as effective antihypertensive and antianginal agents. We have determined the effect of β-blockade in the rat to ascertain whether there are differences between metoprolol (MET) and acebutolol (AC) with respect to regional blood flow (RBF). Both AC and MET were administered as a single or multiple intravenous (iv) doses in Sprague-Dawley rats. Microspheres labelled with 85Sr and 141Ce were used to measure cardiac output (CO) and RBF before and after drug administration. CO and RBF were measured 1 and 10 min after the iv administration of AC (30 mg/kg) and MET (10 mg/kg). After acute administration of MET, CO decreased by 65% and 31% after 1 and 10 min measurements, respectively. These values were 54% and 28% for AC as compared with baseline values. After chronic administration of either AC or MET, however, there were no significant reductions in CO as compared with saline. Both MET and AC significantly reduced RBF in most organs either after 1 or 10 min measurements when compared with the baseline values. It is concluded that both AC and MET reduced CO and RBF after acute administration. The CO and RBF however, returned to normal after chronic administration. Copyright © 2000 John Wiley & Sons, Ltd.