Changes Of AQP4 Expression In The Brain Edema Following Cardiopulmonary Resuscitation And The Intervension Study Of Edaravone

Object To investigate the relationship between dynamic change of a brain edama and AQP4 expression level in rats after CPR. Evaluate the intervention effects of Edaravone.Method 72 Sprague-Dawley male rats were randomly divided into four groups as normal group (n=6,A) ,shame-operated group(n=6,B) , regular CPR group including 1hour,6hours,12hours,24hours,and 72hours after ROSC(5 sub-groups,n=6 for each,C) ,edaravone-treated groups including the same time points as regular CPR groups(5 sub-groups,n=6 for each,D), edaravone intervention after CPR.At each time point measured of MDA(malondialdehyde) in plasma using the method called TBA, calculated the brain water content. The AQP4 expression level in brain tissue was determined using immunohistochemical staining, Neurodeficit Scores were assessed and pathological change was observed.Result The brain water content in rats of C group increased obviously along with the prolongation of time following ROSC ,and reached its peak at ROSC 24h,much higher than that of B group(p<0.01). Meanwhile,the immunohistochemistry of AQP4 had increasing tendency and the integral optical density (iOD) and coloration area ratio(â–³S) were significantly increased versus B group (p<0.01).The change tendency was nearly the same as that of the brain water content. The correlation analysis demonstrated that AQP4 expression level such as integral optical density(iOD) ( r=0.858, p<0.001 ) and the logarithm of coloration area ratio(â–³S) (r=0.870,P<0.001) was correlated apparently with the brain water content . Stereology analytic result found that S-V,NA of nerve cell decreased, VQ increased,manifestly at 24h (p<0.01)after ROSC in C group. There were significant lipid peroxidation occurred within the rat plasma undergoing SCA/CPR , the blood malondialdehyde (MDA)level rise up, reached peak at 6 h after ROSC(p<0.01). In D group the brain water content was decreased obviously ( P<0.05),and iOD andâ–³S were down regulation at the same time (P<0.01). The pathematology damage such as brain edema and neuron necrosis was ameliorated significantly , Stereology analytic result showed S-V,NA of nerve cell increased,VQ decreased versus C group (p<0.05),the blood levels of malondialdehyde(MDA) was significantly declined(P<0.01),The Neurodeficit Scores increased obviously(P<0.05)Conclusion Immune expression intensity of AQP4 increased greatly in rat brain after CPR, the relationship between AQP4 and brain edema was direct correlation. AQP4 may play a role in the formation of brain edema following CPR. Edaravone could eliminate the free radical in plasma and inhibit the expression level of AQP4 to attenuate brain edema and improve neurological outcome of SCA/CPR in rat.