The Effect Of Tetramethylpyrazine On The Expression Of IL-10,IL-18 After Acute Spinal Cord Injury In The Rat Model

OBJECTIVE: To study the effect of Teramethylpyrazine (TMP) on expression of IL-10 and IL-18 in acute spinal cord injury(ASCI) in rats and approach the protective effect and possible mechanism of TMP in ASCI.METHODS : 88 SD rats weighting 250g up to 300g were divided randomly into three groups:(1) Sham operation group (group S, n=8); (2) Control group (group C, n=40); (3) Tramethylpyrazine group (group T, n=40). The modified Allen's model of ASCI at T10 section was established. 200mg/kg of TMP was used to the T group intraperitoneally and the S and C groups were treated with the same volume of saline vehicle (NS) 30 minutes after injury. Each model was given the same dosage once a day until sacrifice or lasted for 5 days following the injury if the rats survived for more than 5 days.The rats of three groups were killed to collect the spinal cord tissue samples from the injured segment with the length of 1cm at the each time point following the injury.Each sample got histological sections of 10um thickness through microtomy in the middle of the sample. The section was prepared to test the IL-10 and IL-18 by immunohistochemistry method separately .The number of ILs in every section was counted ,and the average positive ILs cells of each group at the same time point were calculated. Software SPSS13.0 was applied to analysis if there was significant difference among the three related groups at each time point. Animal behavioral scores—modified Rivilin loxotic plate and BBB score on spinal cord functional deficits were performed to the rats sacrificed at the 24 hour,3 day, 7 day and 14 day following SCI, and analysis the difference betweenthe groupC and group T.RESULTS: The outcomes of rats in modified Rivlin loxotic plate test: T group compared with C group at 7d,14d after SCI respectively (p<0.05).T group had significantly higher scores in BBB test than C group at 7,14 days after SCI respectively(p<0.05).The number IL-10 positive cells were significantly higher in T group than C group at 24h, 3d and 7d after SCI(p<0.05); The number IL-18 positive cells were significantly lower in T group than C group at 12h, 24h,3d,7d and 14d after SCI(p<0.05)CONCLUSION: The TMP have protective effect in the sequential spinal cord injury (SSCI); The TMP can increase the expression of the IL-10 and decrease the expression of the IL-18 after ASCI.