Propofol Inhibits Aquaporin 4 Expression Through Protein Kinase C-Dependent Pathway In Cerebral Ischemia/reperfusion Of Cultured Rat Astrocytes

Objective:The primary pathological processes in cerebral ischemia/reperfusion is Brain edema.Aquaporin 4(AQP4)is a key molecule for maintaining water balance in the central nervous system,and its dysfunction might cause brain edema.However,little is known about the regulation of AQP4 expression.Because propofol has been implicated in brain edema and neuroprotedtive activities.The purpose of this study is to determine whether propofol affects expression of AQP4 in cerebral ischemia/reperfusion models of cultured rat astrocytes.Methods:Here,we constructed the cerebral ischemia/reperfusion models of rat astrocytes and evaluated the expression of AQP4 by Western blot analysis. Meanwhile,we investigated the effect of propofol on AQP4 expression using Western blot analysis.In addition,we examined the role of protein C(PKC)in the effect of propofol on AQP4 expression using Western blot analysis.Results:We found that vability of cell significantly decreased after OGD for 4h,decreased to 60%after OGD for 6h.During reoxygenation 24h,vability of cell ecreased further to 50%.Propofol preconditioned can improve the vability of cells in a dose-dependent manner(p＜0.05).Our data showed protein expression gradually decresed after OGD and reversed by reoxygention.Propofol pretreatment can also decrease protein expression(p＜0.05).We also observed that prolonged pretreatment cells with TPA can reversed significantly(p＜0.05)the effect of propofol on AQP4 protein expression in astrocytes.Conclusion:1.Propofol preconditioned can provide nuroprotective effecs in cerebral ischemia/reperfusion injury models.2.Propofol pretreated can downregulate expression of AQP4.3,Propofol inhibits AQP4 expression through PKC pathway.