Which of the following was not observed in studies measuring the efflux of radioactive sodium from the squid giant axon?

Which of the following was not observed in studies measuring the efflux of radioactive sodium from the squid giant axon?

Which of the following was not observed in studies measuring the efflux of radioactive sodium from the squid giant axon?





  1. Dramatic increase of efflux during a brief train of action potentials
  2. Sharp drop in efflux when extracellular potassium was removed
  3. Dependence of efflux upon the presence of ATP
  4. Decrease of efflux when mitochondrial ATP synthesis was inhibited
  5. All of the above were observed.


Answer: 1