388 ANNALS NEW YORK ACADEMY OF SCIENCES 



point, during activity is fairly equally permeable to cation and anion, 

 to this extent resembling the situation in injury; while, in (c), an 

 additional influence of organic anions has been taken into account, 

 as has been discussed already by Hodgkin and Huxley.- These authors 



d-,,.<j V.S+ _± 1 1 1 ± 1 1_ -its nV (a) 



^"'1 -r-) :: :: :: :: :: :: ; 01^ (b) 



a/opkt>n. 



^--',^'-- ::l::i::t::i::t:: i^ ^-fow (c) 



Figure 2. Diagrams illustrating the reversal of the nerve potential. 



have considered, among others, particularly the lactic acid anion, which, 

 during activity, would penetrate the membrane from inside and pro- 

 duce a negativity outside. However, this hypothesis is rejected by 

 Hodgkin and Huxley themselves, as it would be hard to imagine the 

 concentration and the mobility in the membrane of the lactate ion as 

 being sufficient. Instead, I would prefer to pay attention, especially, 

 to the organic nonpolar-polar, hydrophobic-hydrophilic anions, already 

 mentioned, which possibly can be assumed to be present in the nerve 

 membrane, or, rather, to be liberated as the excitation wave travels 

 along the fiber. As stated earlier, such anions, locally applied to the 

 outside of a muscle, call forth a reversed resting potential, whereas, 

 if they originated during excitation inside, they would call forth a 

 reversed action potential, due to the fact that the adsorption forces 

 would draw these anions into the porous membrane, as shown in figure 

 2(c). Such a reversed resting potential has been found with the salts 

 of higher fatty acids, alkyl sulfates, aryl sulfonates, and others. These 

 experiments should be extended to nerves, especially to single nerve 

 fibers like that of the squid, for the following reason: 



Nonpolar-polar anions are abundantly preformed in the molecules of 

 lipoids of the nervous system, chiefly in phospholipids and cerebrosides. 

 Among their split products, the nonpolar-polar character is especially 

 pronounced in the anions of fatty acids with long carbon atom chains, 

 and, according to Langmuir and Adam, particularly in fatty acids 



