Role Of Annexin A7 In Early Brain Injury After Subarachnoid Hemorrhage In Rats

Objective:The experiments is to investigate the expression of annexin A7 after subarachnoid hemorrhage by models of SAH in rat.Expression of annexin A7 interfered with Lentivirus-ANXA7-siRNA after SAH in the follow-up experiments was related to nerve excitability toxicity.And It may provide a theoretical basis for the clinical treatment of SAH patients and the development of new drugs.Method:1.Models of SAH were induced by intermal caroid perforation filament.Brain water content and EB were detected.The effect of neurological deficits were evaluated by the Garcia score.The morphological features and the amount of neurons in the cortex were observed after Nissl staining.Expression of annexin A7 was detected respectively using western blot and immunofluorescence labeling techniques.2.Lentivirus-ANXA7-siRNA was injected into rat brain by stereotactic lateral ventriculopuncture.Expression of annexin A7 was detected by western blot.The glutamate content in CSF was detected by glutamate assay kit.And to observe the level of apoptosis of nerve cells by TUNEL.Result:1.The expression of annexin A7 in SAH rats was higher than that in the control group(p<0.05).2.In the SAH group,annexin A7 and neurons labeled molecules-NSE exist coexpression;annexin A7 and astrocytes labeled molecules-GFAP does not exist coexpression.3.The expression of annexin A7 in ANXA7-siRNA group was lower than that in SAH group and SAH+Vector group.(p<0.05)4.The content of glutamic acid in the CSF of ANXA7-siRNA group was lower than that in SAH group and SAH+Vector group.(p<0.05)5.The brain water and EB content in ANXA7-siRNA group were lower than that of SAH group and SAH+Vector group.And the neroubehavioral score was higher than that of SAH group and SAH+Vector group.(p<0.05)6.The apoptotic rate of neurons in hippocampus and cortex in ANXA7-siRNA group was lower than that in SAH group and SAH+Vector group(p<0.05).Conclusion:1.Expression of annexin A7 in the cerebral cortex of SAH group were higher than that of control group.2.In the temporal cortex and hippocampus of SAH group,annexin A7 was expressed in the cytoplasm of neurons rather than nucleus.Annexin A7 was not expressed in the astrocytes.3.The up-regulated of annexin A7 is related to the nerve excitability toxicity in EBI after SAH.4.ANXA7-siRNA can significantly reduce the release of glutamate and the apoptosis of nerve cells,alleviate brain edema and destruction of BBB and improve the neurological function of rats after SAH by regulating the expression of annexin A7.And early brain injury after SAH can be effectively alleviated by regulating the expression of annexin A7.