On the two components of the action potential from single nodes of Ranvier in potassium-rich media.

Since the discovery of the restoration of excitability of the nerve in potassium-rich media by application of anodal current(LORENTE DE No,1947; SATO and FUKUDA,1953),particularly recently,many investigations on the behaviours of various excitable membranes in potassium-rich media have appeared(STAMPFLI,1958;MUELLER,1958a,b and c;TASAKI,1959;LUTTGAU, 1959 and 1960;MEVES,1960 and 1961;WRIGHT and OOYAMA,1961;SEGAL, 1958;MOORE,1959;HAGIWARA et al,1961).The fact that the excitable membranes can produce an active response in the potassium-rich solution which is completely deprived of sodium has been admitted by many investigators.On the nature of the activity in the potassium-rich solution considerations have been made either on the basis of ionic theory or on other theories.Those who stand on the ionic theory investigate the active response in the potassium-rich solution as an activity of potassium carrier system(LUTTGAU,1960; MEVES,1960 and 1961;WRIGHT and OOYAMA,1961).On the contrary,some other investigators interpret the fact as manifestation of electromotance (MUELLER,1958c)or of the two stable states(TASAKI,1959;SPYROPOULOS, 1961).Here the active response in potassium-rich media was investigated and it was found that the active response was composed of,at least,two mutuallyindependent processes which depended on sodium and potassium ions respectively.