[The effect of novocaine on the electrical activity of nodes of Ranvier in high  and low pH solutions].
The minimal concentrations of procaine which block the action potentials of a single Ranvier node were determined under decreased and increased pH in the bathing solution. The changes in concentrations of the basic [B] and cationic [BH+] form of procaine with pH were of monotonic character: [B] drops and [BH+] grows with pH increase. The dependence of membrane excitability (fraction of channels are able to excite)  on pH was nonmonotonic; it is low under increased and decreased pH. On the basis of these data the hypothesis that the membrane of the Ranvier node may interact with a definite form of procaine is rejected. T he quantitative analysis shows that the membrane interacts with both the basic and cationic forms of procaine but the efficiency of this interaction is different.
D000200:Action Potentials / Q000187:drug effects*; D000818:Animals; D003864:Depression, Chemical; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D011343:Procaine / Q000494:pharmacology*; D011896:Rana temporaria; D011901:Ranvier's Nodes / Q000187:drug effects*
D011343:Procaine
Vliianie novokaina na élektricheskuiu aktivnost' perekhvata Ranv'e v rastvorakh s vysokim i nizkim pH