Neuroprotective effect of magnesium on lipid peroxidation and axonal function after experimental spinal cord injury

Study design: An experimental study examining the neuroprotective effect of magnesium on axonal function and lipid peroxidation in a rat model of acute traumatic spinal cord injury. Objective: To determine the effectiveness of postinjury treatment with magnesium on evoked potentials and lipid peroxidation after spinal cord injury (SCI). Setting: Pamukkale University, Denizli, Turkey. Methods: Spinal cord injury occurred in 30 rats with an aneurysm clip at T9 and the rats were randomly assigned to undergo subcutaneous administration of one of the following at 1 h after injury: (1) Physiorogical saline (n=10); (2) MgSO4, 300 mg/kg (n-10) and (3) MgSO4, 600 mg/kg (n=10). Spinal somatosensory evoked potentials (SSEPs) were recorded before injury, 30 min after injury and 3 h after injections. Rats were killed 24 h after the injury, and malondialdehyde (MDA) levels were measured. Results: Following SCI, there were significant decreases in the amplitudes of P1 and N1 (P<0.001) and only high-dose magnesium improved the SSEPs (P<0.01). On the other hand, there was significant difference in lipid peroxide content between high-dose magnesium treated group and both of saline treated and low-dose magnesium treated groups (P<0.01). Conclusion: These results suggest that magnesium has a dose-dependent neuroprotective effect on SSEPs and lipid peroxidation after experimental spinal cord injury.