Inhibition of Voltage-Gated Na+ Channels by Bupivacaine Is Enhanced by the Adjuvants Buprenorphine, Ketamine, and Clonidine

Abstract

We demonstrate that buprenorphine, ketamine, and clonidine directly inhibit Na channels and that they potentiate the blocking efficacy of bupivacaine on Na channels. These data indicate that block of Na channels may account for the additive effects of adjuvants used for regional anesthesia.