Duration of lipid peroxidation after acute spinal cord injury in rats and the effect of methylprednisolone.
OBJECTIVE
Oxidative stress leading to lipid peroxidation is a major cause of secondary injury following spinal cord injury (SCI). The objectives of this study were to determine the duration of lipid peroxidation following acute SCI and the efficacy of short-and long-term administration of methylprednisolone on decreasing lipid peroxidation.


METHODS
A total of 226 female Wistar rats underwent clip-compression induced SCI. In the first part of the study, spinal cords of untreated rats were assayed colorimetrically for malondialdehyde (MDA) to determine lipid peroxidation levels at various time points between 0 and 10 days. In the second part of the study, animals were treated with methylprednisolone for either 24 hours or 7 days. Control animals received equal volumes of normal saline. Treated and control rats were killed at various time points between 0 and 7 days.


RESULTS
The MDA levels initially peaked 4 hours postinjury. By 12 hours, the MDA levels returned to baseline. A second increase was observed from 24 hours to 5 days. Both peak values differed statistically from the trough values (p < 0.008). The methylprednisolone reduced MDA levels (p < 0.04) within 12 hours of injury. No effect was seen at 24 hours or later.


CONCLUSIONS
The results of this study indicate that oxidative stress persists for 5 days following SCI in rats, and although methylprednisolone reduces MDA levels within the first 12 hours, it has no effect on the second lipid peroxidation peak.
Christie
Sean D
SD
Department of Anatomy and Neurobiology, Dalhousie University, Halifax, Nova Scotia, Canada. sean.christie@dal.ca
Comeau
Ben
B
Myers
Tanya
T
Sadi
Damaso
D
Purdy
Mark
M
Mendez
Ivar
I
D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003124:Colorimetry / Q000379:methods; D004195:Disease Models, Animal; D015227:Lipid Peroxidation / Q000187:drug effects*; D008297:Male; D008775:Methylprednisolone / Q000627:therapeutic use*; D018696:Neuroprotective Agents / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D013119:Spinal Cord Injuries / Q000188:drug therapy*; D013997:Time Factors
D018696:Neuroprotective Agents; D008775:Methylprednisolone