Gokin et al. studied features of conduction blockade in different classes of rat sciatic nerve fibers after injection of lidocaine via procedures resembling those used inhumans. Thirty adult male Sprague-Dawley rats were initially anesthetized with either urethane or pentobarbital. Longitudinal skin incisions were made to rats’ posterior right hind legs.
In each rat, the sciatic nerve and its main branches (posterior tibial, common peroneal, and sural nerves) were exposed. Impulses in different classes of sensory axons (large, Aα, Aα/β; small, Aδ myelinated fibers and unmyelinated C fibers) and motor axons (large, Aα; small, Aγ myelinated fibers) were recorded and classified by conduction velocity. The sciatic nerve was stimulated distally, and impulses were recorded from small filaments teased from the L4–L5 dorsal and ventral roots sectioned from the spinal cord. Lidocaine, in…
