The myocardial effects of pancuronium

The effect of pancuronium on myocardial contractility was studied in three different animal preparations. Pancuronium produced no change in isometric contraction of rabbit atrial or cat papillary muscle but displaced the acetylcholine dose-response curve to the right in the papillary muscle preparations, verifying a muscarinic blocking effect of this drug. In atropinized dogs in vivo pancuronium produced no significant change in the cardiovascular parameters studied. These studies show that pancuronium exerts its cardiovascular effects primarily by blocking muscarinic receptors in the heart.