Curative effects of naloxone administered early after the injury on diffuse axonal injury in rats

Objective To observe the curative effects of naloxone administered early after the injury on diffuse axonal injury (DAI) in rats. Methods Ninety-nine Wistar rats were randomly divided into control (sham injury) group (n=11), injury group (n=44) and treatment group (n=44, 2.0mg/kg of naloxone were intraperitoneally injected 45 minutes after the injury). The animals in the injury and treatment groups were randomly redivided in 4 subgroups of 11 rats each according to the time when the animals were sacrificed after the injury. The DAI models were made by modified Marmarou's method. The neurological score (NS), the brain water content and the pathological changes were observed 2, 6, 24 and 72 hours after the injury in rats. Results NS was significantly higher in the control group than that in the treatment group (P0.01) where NS was significantly higher than that in the injury group 6, 24 and 72 hours after the injury (P0.05). The brain water content was significantly lower in the control group than that in the treatment group (P0.01) where the brain water content was significantly lower than that in the injury group 6, 24 and 72 hours after the injury (P0.05). The pathological changes were significantly relieved in the treatment group compared to that in the injury group. Conclusion The secondary cerebral damage may be significantly relieved by using high dose of naloxone early after the injury in the rats with DAI.