The Sound of Evolution
Bupivacaine
Mechanism of action:
Bupivacaine is an amide-derived local anesthetic. After entering nerve cells, bupivacaine is converted within the axon into its positively charged ionic form. This ionic form binds to the inner binding site of the voltage-gated Na⁺ channel, specifically in the S6 segment, stabilizing the channel in its inactivated state. As a result, action potentials cannot be generated or conducted, leading to a temporary interruption of sensory, motor, and autonomic nerve signals.
Reference(s):
1. Rosenblatt MA et al. (2006). Successful use of a 20% lipid emulsion to resuscitate a patient after a presumed bupivacaine-related cardiac arrest. Anesthesiology.
2. Picard J et al. (2006). Lipid emulsion to treat overdose of local anaesthetic: the gift of the glob. Anaesthesia.
3. Zhang H et al. (2014). Voltage-dependent blockade by bupivacaine of cardiac sodium channels expressed in Xenopus oocytes. Neurosci Bull.