The Effect Of Local Mild Hypothermia On PAF And TXB2Expression In Peri-Hemorrhage Tissue Of Experimental Rats Following Intracerebral Hemorrhage

Objective: To study the effects of local mild hypothermia on theexpression of platelet-activating factor (PAF)、thromboxane B2(TXB2)and brain edema in peri-hemorrhage tissue of experimental rats followingintracerebral hemorrhage. And to explore the mechanism of action ofmild hypothermia on the treatment of hemorrhagic cerebral edema.Methods: The model of intracerebral hemorrhage were producedby injection of autologous blood to caudate nucleus of SD rats withstereotactic. As a method of mild hypothermia,the ice bags were used totreat the disease side of the head. The contents of PAF andTXB2inperi-hemorrhage were detected by enzyme-linked immunosorbent。Results:1、 The level of PAF and TXB2expression inperi-hemorrhage tissue in rat cerebral hemorrhage rat model weresignificantly higher than the sham-operated group (P <0.05).2、Thecontent of water in brain tissue surrounding hemorrhage in cerebralhemorrhage rat model was significantly higher than the sham-operatedgroup (P <0.05). In mild hypothermia group，the content of water inbrain tissue surrounding hemorrhage was significantly lower than normaltemperature group with the sham group at every time point (P <0.05). 3、The expression of PAF：in mild hypothermia group,the level of PAFexpression was highest on first day, and it decreased significantly (P <0.05)at days3、7. The level of PAF expression was not statisticallysignificant in mild hypothermia group、the control group and the shamgroup. The expression of TXB2：the level of TXB2expression was thehighest in first day，and it decreased significantly at days3、7in mildhypothermia group (P <0.05). The level of TXB2expression of mildhypothermia group were significantly lower than the control group andthe sham group (P <0.05)on3d,however，the level of TXB2expressionof mild hypothermia group was significantly higher than the controlgroup and the sham group (P <0.05). The analysis of PEARSONcorrelation: the content of water in brain tissue surrounding hemorrhagewas not relation to the level of PAF expression (P>0.05),however,Thecontent of water in brain tissue surrounding hemorrhage was relation tothe level ofTXB2expression (P <0.05).Conclusion:1、The level of PAF and TXB2expression was raised inbrain tissue surrounding hemorrhage following cerebral hemorrhage. PAFand TXB2were involved in the formation of the hemorrhage brain edemaby promoting platelet activation、aggregation and vasoconstriction.2、The level of TXB2expression was significantly inhibited by local mildhypothermia. Maybe local mild hypothermia reduce cerebral edemapossibly by inhibiting the TXB2, but the level of PAF expression was not significantly effected by local mild hypothermia. Local mildhypothermia can significantly reduce brain edema after cerebralhemorrhage.