Expression of interleukin-6 and tumor necrosis factor-α in brain tissue and serum of rats with focal brain ischemia

Objective:To study the expression of interleukin-6 (IL-6) and tumor necrosis factor-α(TNF-α) mRNA in ischemic brain tissues and the serum levels of IL-6 and TNF-α in rats with focal brain ischemia. Methods:The rat model of local brain ischemia was established by using intraluminal suture. The rats were killed 6,12,24,and 48 hours after brain ischemia,and the ischemic brain tissue and venous blood were sampled. The expressions of IL-6 and TNF-α mRNA and the serum levels of IL-6 and TNF-α were determined by reverse transcriptional polymerase chain reaction and radioimmunoassay method,respectively. Results:The expressions of IL-6 and TNF-α mRNA in ischemic brain tissue increased,reached the peak after 6 hours,and returned to the baseline after 48 hours. The serum level of IL-6 increased after brain ischemia and reached the peak after 12 hours. The expression of TNF-α mRNA reached the peak after 12 hours. The serum level of TNF-α increased gradually within 48 hours. Conclusion:Focal brain ischemia can induce the high expressions of IL-6 and TNF-α mRNA in ischemic tissue and increase the serum levels of IL-6 and TNF-α.