Silicone rubber microangiography of injured acute spinal cord after treatment with methylprednisolone and vitamin E in rats.

Abstract

An experimental study of changes in the microvasculature of the injured spinal cord that occur with methylprednisolone and vitamin E treatment. To determine the effect of treatment with the methylprednisolone and vitamin E on the microvasculature of the traumatized spinal cord. Silicon rubber microangiography provided an excellent three-dimensional method for defining the distribution of vasculature in untreated and treated rats after injury. Therefore, silicone rubber microangiography was helpful for elucidating the pathophysiology of posttraumatic ischemia and hemorrhages in the spinal cord. In this study, 30 adult rats underwent laminectomy between C7 and T2 followed by extradural spinal cord clipping to produce the compression injury. A control group of 10 rats was left untreated, and 10 rats were treated with methylprednisolone (30 mg/kg bolus and 5.4 mg per hour for 24 hours). Another 10 rats were treated with methylprednisolone and vitamin E (100 U/kg per day). The animals were killed 4, 24, or 48 hours after injury. Silicon rubber microangiography was performed after injury to assess the vasculature of rats' spinal cord. Spinal cord injury causes rapid elevation of noradrenalin, adrenaline, and dopamine. Venous blood samples were taken from all animals before the silicone rubber microangiography was performed. The compression of the spinal cord followed by postinjury treatment with the methylprednisolone and combination methylprednisolone and vitamin E resulted in a ischemic area smaller than that in the untreated group. Adrenaline, noradrenalin, and dopamine levels were less than those in the untreated group. Findings showed that the addition of vitamin E to the methylprednisolone treatment made no difference in the extent of the ischemic area as compared with methylprednisolone treatment given alone. However, the statistical analysis did not show a significant difference between the treated and untreated groups.