Recovery from spinal transection in fish

Abstract

Goldfish had spinal transections at segment 12 and then survived for 47–243 days. Horseradish peroxidase was placed into spinal segment 15 in unoperated and operated fish and labeled neurons were found in: (1) the reticular formation; (2) the vestibular nuclei, and (3) the nuclei of the medial longitudinal fasciculus. The labeled neurons were slightly larger in operated fish and, in general, the longer the fish survived transection, the more cells were labeled. This demonstrates that brain regions whose neurons project from the spinal cord to segment 15 in unoperated fish also project to segment 15 after recovery from transection.