ABSTRACT
AIM: To study the effect of G-protein-coupled receptor kinase 5 (GRK5) on the activation of astrocytesin the brain cortex of newborn Wistar rats .METHODS: GRK5 gene was silenced in the model of rat brain cortexastrocytes in vitro for 24 h.N-acetylcysteine (NAC), which is a known inhibitor of NF-κB, was added into the culture mediumaccording to gene silencing for 24 h.The expression levels of GFAP and caspase-3 were detected by the method of immunofluorescence,and the mRNA levels of NF-κB, TNF-α, IL-1βand iNOS were determined by real-time PCR.Moreover,the activity of SOD and concentrations of TNF -αand NO were measured.RESULTS: GRK5 gene silencing increasedthe expression of NF-κB at mRNA and protein levels obviously (P <0.01), and the mRNA levels of IL-1βand iNOS increasedsynchronously (P <0.01).Furthermore, caspase-3-positive cells in GRK5 siRNA group were increased comparedwith control siRNA group (P <0.01).Treatment with NAC obviously reduced the activity of NF -κB and weakened theeffects induced by GRK5 siRNA (P <0.05).CONCLUSION: GRK5 siRNA increases NF-κB activity and induces the activationof astrocytes.