ABSTRACT
[Objective] To explore the variety of matrix metalloproteinase 9 (MMP9) and blood brain barrier (BBB) in cardiopulmonary resuscitation rats.[Methods] Eighty rats were randomly divided into 2 groups:the sham-operated group (n ＝ 40) and the resuscitation group (n ＝ 40).The two groups were anaesthetized and endotracheally intubated,the resuscitation group was also induced to cardiac arrest by aphysia.Then the rats were put to death and samples were taken at immediate,3 h,9 h,24 h,and 48 h.After that,the expression of MMP9,MMP9 mRNA,water content and Evans blue content in brain tissue were detected.Ultramicrostructure of brain tissue was observed with electron microscope.[Results] Compared to the sham-operated group,at 3 h,9 h,24 h and 48 h,the expression of MMP9 of resuscitation group was significantly changed.MMP9mRNA significantly increased.Water content statistically increased and so was Evans blue content.The change of ultramicrostructure in the resuscitation group at 3 h,9 h,24 h,and 48 h was obvious.[Conclusion] The expression of MMP9 and MMP9mRNA obviously increased in the cerebral ischemia model with CPR rats,and got to peak at 24 h.Water content and Evans blue content in brain tissue obviously increased in the cerebral ischemia model with CPR rats,BBB was destroyed,and the peak was 24 h.The injury of ultramicrostructure of brain tissue with electron microscope was obvious,and the peak was 24 h.