HOBER: THE MEMBRANE THEORY 



387 



For example: According to Furusawa, Feng, and Shanes and Brown/^ 

 during anoxia the polarization of crab nerve and its excitability fall 

 off reversibly, but seem to be maintained in the presence of phos- 

 phopyruvic acid, adenosintriphosphate, and thiamin; in other words, 

 by establishing the normal glycolytic cycle. According to Hoagland 

 and Davis,^° Nitella cells in the dark lose their intracellular chloride 

 ions, through the protoplasmic wall, into the surrounding water and 

 recapture them during exposure to light. Furthermore, according to 

 J. E. Harris, ^^ potassium ion gets lost from human erythrocytes at low 

 temperature, but re-enters at room temperature, after addition of 

 glucose. 



REVERSAL OF THE NORMAL ACTION POTENTIAL 



I now come back to the lately-discovered fact, already mentioned, 

 that the potential change during action does not equal the resting 

 potential in magnitude, as it was assumed for many years. Rather, 

 by overshooting the zero line, as shown in figure 1, the potential is 



Figure 1. Potential of the internal electrode. The figure shows that the resting potential is 

 — 44 mV. During activity, the potential overshoots to the positive side, +40 mV, so that the 

 action potential wave amounts to 84 mV. ( Hodgrkin & Huxley^.) 



momentarily reversed in sign, the outside of the membrane becoming 

 negative to the inside. This reversal during passage of the impulse 

 does not fit into the classical picture of the behavior of the active nerve 

 membrane, and possibly indicates a special mechanism, which is super- 

 imposed to the mechanism of the customary excitation depolarization. 

 Figure 2 depicts three conditionsof the nerve membrane: (a) represents 

 the normal polarization of a resting nerve membrane; (b) is indicative 

 of the depolarized membrane, which, according to the ordinary view- 



