Verapamil Potentiate the Cardiodepressor Effect of
Ethanol in Cat Papillary Muscle
José L. Martínez1*,
Hiran Cabrera2 and Claudio Laurido3
1University
of Santiago of Chile, Office of the Vice Rectory, Alameda 3363, Est.
Central, Santiago, Chile; 2Central
Laboratory of Pharmacology, Faculty of Medical Sciences Dr. Salvador
Allende, University of Medical Sciences, Havana, Cuba; 3University
of Santiago of Chile, Faculty of Chemistry and Biology, Santiago,
Chile *Corresponding author: editor.blacpma@usach.cl
Abstract
The possible additive effect of ethanol (EtOH) on
verapamil on isolated papillary muscle of cats weighing 1200-1500 g kept in oxygenated
Ringer Locke solution was studied. Papillary muscles were dissected from the
right ventricle, mounted vertically in an acrylic support and stimulated
electrically drivenat a constant rate by
means of silver at 37oC (pH=7.4). We studied the effect on peak
tension development (PTD) of verapamil (5.4 X 10-4 mM)
and two EtOH concentrations (48.6 and 97.2 mM) in cat papillary
muscle bathed in a normocalcic medium (2.2 mM) of Ringer-Locke solution.EtOH in both concentration potentiated the decrease of PTD (inotropic
effect), (-53.31±2.07% and -60.00±3.50%, respectively) compared to verapamil
previously incubated in bath (-38.1±2.26%). It was concluded that verapamil
induces a decrease in myocardial contraction by a posterior consumption of
sufficient EtOH enough to put the patient in the risk of a lamentable induction
of cardiac failure.