RESUMEN
OBJECTIVE To study the protective effects of twin drugs of tetramethylpyrazine-scutellarein （TMSC4） on cerebral ischemia-reperfusion injury （CIRI） model rats and its mechanism. METHODS One hundred and five SD rats were randomly divided into sham operation group， model group， scutellarein group （0.7 mmol/kg）， tetramethylpyrazine group （0.7 mmol/kg）， and TMSC4 low-dose， medium-dose and high-dose groups （0.35， 0.7， 1.4 mmol/kg）， with 15 rats in each group. Sham operation group and model group were given constant volume of normal saline intragastrically， and other groups were given relevant drug intragastrically， once a day， for consecutive 14 d. Except for sham operation group， all other groups were treated to establish the CIRI model using the thread occlusion method. After 2 hours of ischemia and 22 hours of reperfusion， the brain index and brain water content of the rats were measured. Serum levels of interleukin 1β （IL-1β）， IL-6 and tumor necrosis factor α （TNF-α）， the levels of superoxide dismutase （SOD）， malondialdehyde （MDA）， glutathione peroxidase （GSH-Px） and catalase （CAT） in brain tissues， the situation of neuronal cell apoptosis， and the protein expressions of B-cell lymphoma 2 （Bcl-2）， Bcl-2-associated X protein （Bax） and cleaved-caspase-3 were evaluated. RESULTS Compared with sham operation group， the brain index， brain water content， the serum levels of IL-1β， IL-6 and TNF-α， the levels of MDA in brain tissues， the brain cell apoptosis and the protein expressions of Bax and cleaved-caspase-3 in model group were significantly increased （P＜0.05）； the levels of SOD， GSH- Px and CAT and the protein expression of Bcl-2 in brain tissues were significantly decreased （P＜0.05）. Compared with model group， the above indexes of rats were reversed significantly in administration groups （P＜0.05）， while the reverse effects of TMSC4 medium-dose and high-dose groups were significantly better than those of scutellarein group and tetramethylpyrazine group （P＜0.05）. CONCLUSIONS TMSC4 has a certain protective effect in CIRI model rats， the mechanism of which may be related to relieving inflammatory reaction and oxidative stress， inhibiting cell apoptosis.