Local anesthetic drugs are effective only at the nodes of Ranvier and in order to be effective, multiple nodes must be exposed to the drug to block impulses.

Question

Quizplus · Accepted Answer

Local anesthetic drugs block nerve impulses by inhibiting sodium channels, which are concentrated at the nodes of Ranvier in myelinated nerves. For effective nerve blockage, the drug must affect multiple nodes to ensure the impulse is sufficiently inhibited along the nerve.

Local Anesthetic Drugs Are Effective Only at the Nodes of Ranvier