[The effect of articaine on isolated peripheral nerves].

The effects of a new local anesthetic articaine (Spofa) (licence of the firm Hoechst) on isolated sciatic nerve were tested. Its actions were compared with the effects of rapidly and shortly acting lidocaine and with a newly synthetized long acting local anesthetic carbizocaine--derivative of carbanillic acid. Articaine acted 3 times more slowly than lidocaine, although it was twice as effective. EC50 showed carbizocaine to be 40 times more effective than articaine at pH 7.2 and its action was slower and prolonged. On lowering external pH, the blocking effects of articaine and lidocaine were diminishing, but the effect of carbizocaine was profound. The nerve sheath decreased and slowed down the local anesthetic activity of articaine. The results indicate that in the light of its pharmacodynamic properties articaine can be arranged with local anesthetics similar to lidocaine. (Tab. 2, Fig. 4, Ref. 19.).