ON THE TWO COMPONENTS OF THE ACTION POTENTIAL FROM SINGLE NODES OF RANVIER IN POTASSIUM-RICH MEDIA

抄録

1. With the single Ranvier's node of frog and toad, the active response in potassium-rich media (nominated here as “K-excess action potential”) was studied.
2. The active response in the potassium-rich media could be separated in two components with their difference in characters for the time course, refractory, dependence on sodium and potassium ions, sensitivity to cocaine, threshold membrane potential level for firing and the time course of reactivation.
3. These two processes were the faster component and the slower one, and coincided with the sodium carrier system and potassium carrier system in the ionic theory, respectively.
4. It was presented that both of sodium and potassium carrier system behaved similarly in many respects except the significantly slow time course of the latter.
5. From the experimental facts it was concluded that these two components were mutually independent processes.
6. Some results on the anodal break response were presented and the interpretation was made in the above stated conclusion.
This work was supported partly by a grant from the Ministry of Education of Japan.