A quantitative comparison of the antagonism of tubocurarine and diallylnortoxiferine by four anticurare agents

Abstract

Abstract The antagonism of tubocurarine and diallylnortoxiferine by neostigmine, physostigmine, edrophonium and ambenonium, has been examined on the rat phrenic nerve diaphragm preparation. Ambenonium showed the greatest activity and physostigmine and edrophonium were the least potent and equally active. This order applied to both neuromuscular blocking agents, but all four antagonists show significantly greater activity against diallylnortoxiferine. The possibility that neostigmine and physostigmine have some qualitative differences in anticurare mechanism compared with edrophonium and ambenonium, on this preparation, is discussed.