A study of the increased sensitivity of denervated and re-innervated muscle to depolarizing drugs.
1. The response of re-innervated muscles to depolarizing blocking drugs was studied.2. 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.3. This increased sensitivity does not appear to be characteristic of all newly formed neuromuscular junctions. It was found that in new-born kittens the muscles are very insensitive to neuromuscular blocking drugs.4. It is concluded that 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.
D000818:Animals; D002415:Cats; D003650:Decamethonium Compounds / Q000494:pharmacology*; D009121:Muscle Denervation; D009416:Nerve Regeneration; D009469:Neuromuscular Junction / Q000187:drug effects*; D013390:Succinylcholine / Q000494:pharmacology*; D014403:Tubocurarine / Q000494:pharmacology*
D003650:Decamethonium Compounds; D013390:Succinylcholine; D014403:Tubocurarine