Effect Of Nuclear Factor-κB Signaling Pathway On The Expression Of Aquaporin-4 MRNA In Rat Brain After Cardiopulmonary Resuscitation

Objective: To investigate the effect of nuclear factor–κB(NF–κB) signaling pathway on the expression of aquaporin-4 mRNA in rat brain after cardiopulmonary resuscitation(CPR)and study the mechanism of the expression of aquaporin-4 mRNA following CPR.Methods: 54 male Sprague-Dawley rats were randomly divided into three groups: group A(sham procedure,n=6), group B (control,n=24) and group C (nuclear factor -κB inhibitor pyrrolidine dithiocarbamate , PDTC , infusion,n=24). Group B and group C were again divided into after ROSC 3, 6, 12, 24 h four subgroups(n=6). The cardiac arrest model of rat was duplicated by asphyxy method.Immunohistochemistry method was adopted to analyse the level of NF–κB p65. The expression of AQP-4 mRNA was assessed by semi-quantitative reverse transcription polymerase chain reaction(RT-PCR).Results: The levels of NF–κB p65 and AQP-4 mRNA of group B and group C were significantly up-regulated at all time points after restoration of spontaneous circulation (ROSC) compared with group A (p<0.01). PDTC resulted in a significant decrease in AQP-4 mRNA expression in group C compared with group B (p<0.05). The correlation analysis demonstrated further that the level of NF–κB p65 was correlated apparently with the expression level of AQP-4 mRNA in brain tissue within ROSC 12h(r>0.775,p<0.01).Conclusion: The levels of NF–κB p65 and AQP-4 mRNA increased at early stage after CPR, and inhibition of the NF–κB signaling pathway (PDTC) decreased the expression of AQP-4 mRNA .These findings show that the NF–κB signaling pathway may play an very important role in the expression of AQP-4 mRNA after CPR in rat brain.