A study of the increased sensitivity of denervated and re-innervated muscle to depolarizing drugs

Abstract

During the early stages of re-innervation the ''new'' neuromuscular junctions are more sensitive to decamethonium and suxamethonium. The recovery from the block and the repolarization of the end-plate are markedly slowed. This increased sensitivity does not appear to be characteristic of all newly formed neuromuscular junctions. In new-born kittens the muscles are very insensitive to neuromuscular blocking drugs. The increased sensitivity of re-innervated muscles to depolarizing blocking drugs and the slow repolarization are due to a persistence of changes which developed during denervation.