Nitroglycerin and the Neuromuscular Blockade Produced by Gallamine, Succinylcholine, d???Tubocurarine, and Pancuronium

Abstract

The finding in cats of prolonged pancuronium neuromuscular blockade in conjunction with intravenous infusion of nitroglycerin was previously reported by this laboratory. To expand on this finding the present study compared the effects of nitroglycerin on neuromuscular blockade produced by gallamine, d-tubocurarine, succinylcholine, and pancuronium, and further characterized the nitroglycerin-pancuronium interaction. The results indicate that of the relaxants studied only pancuronium neuromuscular blockade is prolonged, and that the prolongation is not due to altered plasma elimination of pancuronium. In vitro pancuronium blockade was not affected by nitroglycerin, suggesting the involvement of a metabolite in the block prolongation response. Reversibility of the prolonged pancuronium block by neostigmine is not influenced by nitroglycerin.