COMBINED TREATMENT WITH NICARDIPINE, PHENOBARBITAL, AND METHYLPREDNISOLONE AMELIORATES VASOGENIC BRAIN EDEMA

Free radicals formed around the edematous areas of the brain can cause lipoperoxidation of the cellular membrane, followed by calcium influx into the cell through calcium channels. These secondary insults may a ggravate vasogenic brain edema. Since phenobarbital is a free radical scavenger; methylprednisolone has an antilipoperoxidation effect; and nicardipine is a calcium channel blocker, we hypothesized that combine d treatment with phenobarbital, methylprednisolone, and nicardipine wo uld be beneficial in vasogenic brain edema. This hypothesis was tested in Sprague-Dawley rats with a transdural cold-injury on the right par ietal cortex. The animals were randomly divided into two groups. Anima ls in the treatment group were injected intraperitoneally with phenoba rbital (4 mg/kg), methylprednisolone (50 mg/kg), and nicardipine (10 m ug/kg) at 5 min and 8 hours after the cold-injury. The control animals were injected with saline. These animals were sacrificed 24 hours aft er the injury. The extent of brain edema was assessed by measuring the water content , the inulin distribution volume, and the distribution area of Evans blue in the brain. Our results showed that the water con tent of the edematous hemisphere was similar in the control and the tr eatment groups. However, Evans blue distribution area and inulin distr ibution volume of the treatment group were less than those of the cont rol group by 12% and 31%, respectively. In conclusion, the combined tr eatment with phenobarbital, methylprednisolone and nicardipine is bene ficial in vasogenic brain edema.