Spinal Cord Injury and Assays for Regeneration

Due to their renowned regenerative capacity, adult zebrafish are a premier vertebrate model to interrogate mechanisms of innate spinal cord regeneration. Following complete transection to their spinal cord, zebrafish extend glial and axonal bridges across severed tissue, regenerate neurons proximal to the lesion, and regain swim capacity within 8 weeks of injury. Here, we describe methods to perform complete spinal cord transections and to assess functional and cellular recovery during regeneration. For spinal cord injury, a complete transection is performed 4 mm caudal to the brainstem. Swim endurance is quantified as a central readout of functional spinal cord repair. For swim endurance, zebrafish are subjected to a constantly increasing water current velocity until exhaustion, and time at exhaustion is reported. To assess cellular regeneration, histological examination is performed to analyze the extents of glial and axonal bridging across the lesion.