In vivo recording of nerve conduction velocity of spinal CNS fibers in the mouse.

摘要

Anesthetic and surgical procedures and an electrophysiologicalmethod were developed for recording nerve conduction velocity(NCV) of CNS fibers in the murine spinal cord. Under intravenousanesthesia and artificial ventilation the lumbar spinal cordsegments L1 to L4 and dorsal roots L3 to L5 on the left side wereexposed by laminectomy. After stimulation of the dorsal root L4,a compound action potential (CAP) was recorded at the ipsilateralleft fasciculus gracilis at the spinal cord level L1. The latency fromstimulation to the CAP together with the measured distancebetween the electrodes was used for the determination of theNCV. NCV of the fastest fibers in the fasciculus gracilis wasobserved to be approximately 28 m/s. Reversible decrease of theNCV was measured, in vivo, under general hypothermia. Thetechnique described serves for in vivo electrophysiologicalinvestigations of spinal central fibers in wildtype and mutantmice.