Evaluation of Methylprednisolone Dosing Regimen in Experimental Diffuse Brain Injury

Kim, Ki Chan; Park, Chong Oon; Hyun, Dong Keun; Ha, Young Soo

Abstract

The present study was undertaken to examine the ability of a single large intraperitoneal dose of methylprednisolone(15, 30, 40, 60mg/kg) to modify the evolution of diffuse brain injury(DBI) in rats undergoing a contusion injury of 400gm-1m. Twenty five Sprague-Dawley rats were divided to five groups. Group 1 was not treated after cranial impact as control. Rats in group 2, 3, 4, 5 were treated with 15-mg/kg, 30-mg/kg, 40-mg/kg, 60-mg/kg methylprednisolone dose at 1 hour after injury, respectively. After 24 hours, these rats were sacrificed, and the water content of the whole brain were measured. When the water content was assumed as the criterion of brain edema, there was significant difference between control group(71.03+/-.42%) and group 2(67.34+/-.07%), group 3(66.43+/-.36%), group 4(64.52+/-.11%)(p<0.01). On the other hand, there was no significance between control group(71.03+/-.42%) and group 5(69.74+/-.53%) (p>0.01). This study shows that megadose of methylprednisolone in 15, 30, or 40mg/kg reduces the brain edema, and the its effect is biphasic in that the 60-mg/kg methylprednisolone dose is ineffective.