Effect on serum S-100β protein contents and neural function in rats with cerebral contusion and laceration by injecting IL-1ra into their lateral ventricle

Abstract

Objective To investigate the effect of IL- 1ra on S- 100β protein contents of serum and the behavior scales of neural function in rats with cerebral contusion and laceration by injecting IL-1ra into their later ventricle, and to explore the possible mechanism underlying the nerve protection of IL-1ra. Methods Male Wistar rats were randomly divided into 3 groups:normal saline group(NS group, NS 5 μL injected into the left cerebral ventricle), IL-1ra group (IL-1ra 5 μg/5 μL injected into the left cerebral ventricle), and control group. After half an hour, cerebral contusion and laceration model was made according to Feeney's method in rats of NS group and IL-1ra group. The serum levels of S-100β protein in rats of each group were measured by ELISA at 6 h,12 h,24 h,2 d,3 d,7 d after hitting; and the behavior scales of neural function in all rats were evaluated based on Faden's method.Results (1)The level of serum S-100β protein was (0.43±0.04) μg/L, the score of neural function was 35 in rats of control group.(2)All the model rats' serum concentration of S-100β was higher than that of the control group markedly (P＜0.05) after injury.(3)S-100β concentration of rats in IL-1ra group was significantly lower than that of NS group at the each time point after injury (P＜0.05), and the scores of neural function were higher than those of NS group (P＜0.05). Conclusions (1)IL-1ra can decrease the level of serum S-100β protein and raise the behavior scores of neural function in rats. (2)IL-1ra has brain protective effect after cerebral injury, which may be related to the decrease of the inflammatory reaction of brain cell mediated by IL-1β. Key words: Cerebral contusion and laceration; IL-1ra; IL-1β; S-100β protein