Magnesium sulfate treatment in experimental spinal cord injury: emphasis on vascular changes and early clinical results

Injury to the spinal cord results in disruption of neurons, cell membranes, axons, myelin, and endothelial cells. The aim of this study was to demonstrate the protective effect of magnesium sulfate on the blood-spinal cord barrier after acute spinal cord injury (SCI). This experiment was conducted in two parts. In the first, rats were injected intravenously with Evans blue 2 h after SCI. The laminectomy-only group had no trauma. Contusion injury (50 g-cm) was applied to the trauma and treatment groups. Magnesium sulfate (600 mg/kg) was given to the treatment group immediately after injury. For the second part, clinical evaluations were performed 24 h post surgery. Then, following Evans blue injection, spinal cord samples were obtained from the laminectomy-only, trauma, and treatment groups. For the control group, nontraumatized spinal cord samples were taken after Evans blue injection following clinical examination. Laminectomy did not affect the spinal cord Evans blue content in 2-h and 24-h groups. The trauma increased tissue Evans blue content, and 24-h samples showed more remarkable tissue Evans blue content, suggesting secondary injury. Application of 600 mg/kg of magnesium resulted in lower Evans blue content in the spinal cord than with injury. Remarkable clinical neuroprotection was observed in the treatment groups. Magnesium sulfate showed vaso- and neuroprotective properties after contusion injury to the rat spinal cord. The authors also demonstrated secondary injury of the blood-spinal cord barrier with the Evans blue clearance technique for the first time.