Effects of nickel ion on the conduction of action potentials in non-myelinated nerve fibre of crayfish.
Effects of NiCL2 and PCMB (p-chloromercuribenzoate) on the action potential were examined by the method of extra- and intracellular electrodes, using a single nerve fibre of crayfish. The results obtained were as follows : The conduction of the action potential was blocked by treating the nerve fibre with Ni ion or PCMB. The blockade was easily recovered by replacement with cysteine. The process of the blockade and recovery, which could be repeated several times, was fairly characteristic such that the more repetition led the sooner blockade and the harder recovery. No conduction block was observed by treatment with Ni-cysteine mixed solution nor with PCMB-cysteine solution. The critical concentration for blocking was 1.1 x 10(-4)M for NiCL2 and 5.6 x 10(-6) M for PCMB. The action potential was disappeared without any change in the resting potential by treatment with the chemicals, which gave significant effects on the rising and falling phases of the action potential before the blockade.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D003400:Astacoidea; D002729:Chloromercuribenzoates / Q000494:pharmacology; D003545:Cysteine / Q000494:pharmacology; D005260:Female; D009186:Myelin Sheath / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D009532:Nickel / Q000494:pharmacology*
D002729:Chloromercuribenzoates; D009532:Nickel; D003545:Cysteine