Effects of steroids on behavior, electrophysiology, water content and intracranial pressure in cerebral cytotoxic edema

Abstract

The effect of therapy with methylpredisolone sodium succinate (5.33 mg/kg/day) and dexamethasone sodium phosphate (1 mg/kg/day) on grey matter of rabbits rendered edematous by a metabolic blocker, 6-aminonicotinamide, is presented. Methylprednisolone was observed to significantly reduce the water content of the grey matter ( p<0.001), whereas dexamethasone had little effect. Both agents, however, were equally effective in reducing intracranial pressure ( p<0.001) and improving intracranial elastance, when compared to untreated animals. However, in the dexamethasone-treated group, there was improved behavior and EEG findings in 50% of the animals when compared to the untreated controls, and similar improvement was present in less than 15% of the methylprednisolone group. The disparity between the effects on water content, behavior and EEG supports the thesis that in cerebral edema these agents have a metabolic effect out of proportion to their effect on tissue water.