Methylprednisolone does not decrease eicosanoid concentrations or edema in brain tissue or improve neurologic outcome after head trauma in rats

Methylprednisolone was recently reported to significantly improve motor and sensory function after acute spinal cord injury in patients. Our study was designed to determine whether methylprednisolone exerts a beneficial effect after head injury. Diethyl ether-anesthetized rats were assigned to receive surgery with no cranial impact and no methylprednisolone (group A, n = 13); surgery with no cranial impact and intraperitoneal methylprednisolone (≥ 60 mg/kg) (group B, n = 8); surgery with cranial impact and no methylprednisolone (group G, n = 8, and group E, n = 8); or surgery with cranial impact and methylprednisolone (≥ 60 mg/kg) (group D, n = 15, and group F, n = 13). Neurologic severity score was determined at 1, 2, 4, and 24 h (when appropriate) after injury, and brain tissue eicosanoid levels and cerebral edema were determined when the animals were killed (4 h after injury in groups G and D and 24 h after injury in groups E and P). Treatment with methylprednisolone did not improve neurologic severity score or edema formation and did not alter brain tissue levels of prostaglandin E₂, thromboxane B₂, or 6-keto-prostaglandin F₁(α) at any time period. The authors conclude that methylprednisolone does not exert a beneficial effect on brain tissue edema or functional activity after cranial impact in rats.