Effect of thyroxin on neuronal apoptosis,serum NSE and IL-6 in rats with severe traumatic brain injury / 重庆医学

ABSTRACT

Objective To explore the protective effect of thyroxin on severe traumatic brain injury of brain tissue by observing the effect of thyroxin on neuronal apoptosis,serum neuronal specific enolase(NSE),interleukin-6 (IL-6) and serum FT3 and FT4.Methods A total of 90 SD rats was randomly divided into control group,model group,low dosage of levothyroxine sodium tablets group,moderate dosage of levothyroxine sodium tablets group and high dosage of levothyroxine sodium tablets group,18 rats in each group.The animal model was reproduced by referring to Feeney's free fall impact modeling.Intragastric administration was performed at 6 h after injury.The levels of neuronal apoptosis and serum NSE,IL-6,FT3 and FT4 were detected by TUNEL method,ELISA method and radioimmunoassay at 24,72,168 h after intragastric administration.Results (1) After severe traumatic brain injury,the levels of serum FT3 and FT4 were under the normal and the level of FT4 was decreased to the lowest at 168 h.Thyroxine could increase the levels of FT3 and FT4.(2) Significant neuronal apoptosis was observed in rats with severe craniocerebral injury,and the apoptosis continued until 168 h.Moderate and high dose of thyroxine could improve neuronal apoptosis within 24 h,while low dose of thyroxine changed within 168 h.(3) The levels of serum NSE and IL-6 were increased significantly in rats after severe traumatic brain injury until 168 h,and they could be decreased by moderate and high dose of thyroxine within 72 h.Conclusion Exogenous thyroxine can protect brain tissue in rats with severe traumatic brain injury.