[Relations between the physico-chemical properties, the chemical reactivity and the local-anesthetic activity/part 33: studies on the interactions of local-anesthetically active cinchocaine homologues with phospholipids (author's transl)].

The general part consists of a review on nerve stimulus mechanism as well as the nerve structure and the function of nerve membrane as the site of action of local anesthetics. Furthermore a possibility of interaction between local anesthetics and the membrane components especially phospholipids is discussed. These phospholipids show interesting properties with respect to ions as well as local-anesthetics, which allow us to suppose that they are important participants in nervous stimulus transmission. In the experimental part two methods are described. The first deals with the measurement of electrical resistance as function of time at cephalin and cholesterin impregnated filter membrane in solutions of cinchocain homologues. An increase in the resistance with the increase in concentration of test substances was observed. The same was the effect of increasing chain length in alkoxy group where after butoxy derivative, a deformation of membrane was observed. In the second method the drug binding capacity of cephalin dispersed in aqueous medium was measured. Here, too, the increase in the binding capacity with the increase in alkoxy chain was observed. The large difference in free binding energy between two subsequent homologues is explained as the effect of increase in van der Waals' forces and hydrophobic interactions on one hand, and a change in colloidal form of cephalin dispersion on the other hand.