The Comparison Of Two Kinds Of Animal Models Of Cerebral Hemorrhage And Aqp4 Expression Regulation Mechanism Research

Objective:The aim of this study was to compare collagenase injection induced intracerebral hemorrhage animal model with that induced by autologous blood injection, in order to provide reference for study of pathologic mechanism and/or intervening therapy of intracerebral hemorrhage.Methods:300healthy male adult SD rats (200-250g) were randomly divided into ICH group and the sham operation group. ICH models were established by infusing Collagenase and autologous blood into right caudate nucleus in rats. The operation procedure of the sham group was as same as the ICH group but without infusing drug. The hematoma volume were measured by magnetic resonance imaging (MRI).The changes of brain water content (BWC) were measured by wet and dry weight methods. EB was used to measure the integrity of BBB. The expression of AQP4were detected by immunofluorescence and Western-blot after6h、12h、24h、48h,72h and7d.Results:The hematoma volume in collagenase group reached its peak at24h and continues at72h, in autologous blood group reached its peak at12h and already close to normal at72h, sham group no bleeding in the brain. BWC was reached its peak at24h and continues at72h in collagenase group, whereas on7d is still higher than autologous blood group, in autologous blood group, BWC was reached its peak at24h and gradually decreased at48h and return to normal at7d, sham group without obvious brain edema, At48h and after each time point in two groups, BWC has a significant different (P<0.05).EB contents was reached its peak at12h and continues at48h in collagenase group, whereas on7d is still higher than autologous blood group, in autologous blood group, EB contents was reached its peak at12h and gradually decreased at24h and return to normal at48h, At24h and after each time point in two groups, EB contents has a significant different (P<0.05).A number of swelling AQP4positive cells appeared in the granulose cell layer of rat cerebral cortex in autologous blood group at24h, but none of it was observed in collagenase group at12h. The contents of AQP4had a significant different (P<0.05) in the two groups at6h and after each time point by Western-blot.Conclusions:There was different in the two ICH groups, autologous blood group is relatively close to clinical ICH conditions, Objective:To investigate the changes of arginine-vasopressin Via receptor (V1aR) and aquaporin4(AQP4) expression, to explore the mechanism of brain edema caused by ICH.Methods:120healthy male adult SD rats (200-250g) were randomly divided into two groups, the ICH group and the sham group. ICH models were established by infusing autologous blood into right caudate nucleus in rats. The operation procedure of the sham group was as same as the ICH group but without infusing autologous blood. The changes of brain water content (BWC) were measured by wet and dry weight methods. The expression of V1aR and AQP4were detected by immunofluorescence and Western-blot after6h、12h、24h and48h.Results:BWC was reached its peak during the24-48h in ICH group, significant higher than sham group (P<0.05), V1aR and AQP4co-expression increased at leptomeningeal、chorioid plexus and the tissue surrounding the hematoma at24h in ICH group, whereas in sham group, V1aR and AQP4co-expression small amount of at chorioid plexus, none of it is observed in the surrounding of ventricle.The contents of ViaR and AQP4has a significant higher than sham group (P<0.05) at6h and after each time point by Western-blot.Conclusions:The increased expression of AQP4mediated by V1aR played an important role in the brain edema after ICH.