The effects of metoprolol and dazmegrel, alone and in combination, on arrhythmias induced by coronary artery occlusion in conscious rats

British Journal of Pharmacology
I LepránC L Wainwright

Abstract

The effects of metoprolol and the thromboxane synthetase inhibitor dazmegrel, alone and in combination, were examined in a model of coronary artery occlusion in conscious rats. In a dose (2 mg kg-1), intravenously, that resulted in a marked bradycardia (of 50-80 beats min -1) metoprolol did not influence the incidence or severity of the ventricular arrhythmias that occur in the first 20 min following occlusion, nor did it improve survival (assessed at both 20 min and 16 h). In a dose (5 mg kg-1), intravenously, that in another conscious rat model involving tissue hypoperfusion inhibited thromboxane production, dazmegrel also did not modify ischaemic arrhythmias or survival. In contrast, metoprolol and dazmegrel (2 mg kg-1 and 5 mg kg-1 i.v.) when given together prior to coronary artery occlusion, produced a significant reduction in mortality both at 20 min and 16 h (e.g. from 60-75% in the control, metoprolol alone and dazmegrel alone groups and only 25% in the combined-treatment group). This was due to a decrease in the incidence of terminal ventricular fibrillation. The results suggest that a combination of beta-adrenoceptor blocking drug with a drug that inhibits thromboxane synthesis may offer more protection against ischae...Continue Reading

References

Aug 1, 1982·Journal of Molecular and Cellular Cardiology·S J CokerI J Zeitlin
Jan 16, 1981·European Journal of Pharmacology·I LepránL Szekeres

Citations

Jan 20, 1987·European Journal of Pharmacology·C L Wainwright, J R Parratt
Dec 10, 1991·European Journal of Pharmacology·P Salinas, S Barrigón
Jan 1, 1985·Molecular Aspects of Medicine·J H BottingM J Walker
Oct 1, 1989·Archives internationales de physiologie et de biochimie·S Dai

Related Concepts

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Cardiac Depressants
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