AIM To explore whether plasma vasoactive substances and neutrophil infiltration make different contribution in cerebral ischemia-reperfusion
injury and protective effect of
triacetylshikimic acid(TSA).METHODS The rat models of ischemia 90 min and reperfusion 3-48 h were prepared with middle cerebral artery occlusion. TSA 50-200 mg·kg~ -1 were given (ig) immediately and 60 min again after the onset of ische- mia. Serotonin and
thromboxane B_2 (TXB_2) concentrations in plasma were detected by fluorescence spectrophotometry and radioimmunoassay respectively. Myeloperoxidase(MPO) activity in brain tissue was quantified by chemical analysis.RESULTS At 3-24 h after reperfusion, the concentrations of plasmic serotonin, TXB_2, and brain MPO activity increased obviously in a time-dependent manner. At 48 h after reperfusion, the concentrations of serotonin and TXB_2 decreased to the same level of sham. Nevertheless, brain MPO activity remained more elevated than the contralateral cortex. At 24 h after reperfusion, TSA (100 and 200 mg
·kg~ -1 ) was shown to possess the ability to inhibit the increased plasmic serotonin, TXB_2 concentrations, and brain MPO activity induced by focal cerebral ischemia-reperfusion.CONCLUSION Vasoactive substances in plasma and MPO activity in brain tissue show different time courses during focal cerebral ischemia-reperfusion and make different contribution to brain damage. TSA is effective to protect the ischemic brain tissue from ischemia- Received date: 2005-08-01 Accepted date:2005-11-11 Foundation item:The project supported by New Drug Investigation and Industrial Development Grant of State Science and Technology Commission(96-901-01-35); and National Basic Research Program of China(G1999054400) Biography:LI Xin-Zhi(1974-), male, native of Qingdao, Shandong Province, assistant professor, main research field is cardiovascular pharmacology. ~*Corresponding author. Tel and Fax: (010)62886691 E-mail: lxinzhi@yahoo.com.cn reperfusion injury.