Effect of P2X7 receptor antagonist BBG against hypoxia/reoxygenation injury of astrocytes in rat

Objective: To investigate the protective effects of P2X7 receptor antagonist BBG against hypoxia/reoxygenation(H/R) injury of astrocytes in rat,and explore its mechanisms. Methods: The astrocytes from 10 newborn SD rats were primarily cultured,and divided into the control group,H/R group,BBG(50 nmol/L) + H/R group.The astrocytes viability was detected by MTT assay.Function of gap junction(GJ) of astrocytes was evaluated using fluorescent tracer technique.The expression levels of Cx43,Bax and Bcl-2 were detected by Western blotting.The astrocytes apoptosis was detected by Hoechst 33258 staining assay. Results: The results of MTT assay showed that the viability of rat astrocytes injured by H/R significantly decreased(P<0.01),and the viability of rat astrocytes injured by H/R significantly increased after pretreatment of 50 nmol/L BBG(P<0.01).The results of fluorescent tracer technique showed that the gap junction function of astrocytes exposed to H/R strenghened(P<0.01).The results of Western blotting showed that the expression levels of Cx43 and Bax/Bcl-2 increased(P<0.01).After pretreatment with 50 nmol/L BBG,the gap junction function of astrocytes exposed to H/R decreased(P<0.05),and the expression levels of Cx43 and Bax/Bcl-2 decreased(P<0.05).The Hoechst 33258 staining assay showed that the apoptosis rate of rat astrocytes exposed to H/R significantly increased(P<0.05),and the apoptosis rate of rat astrocytes exposed to H/R decreased after pretreatment with BBG(P<0.01). Conclusions: can protect the rat astrocytes injured by H/R,the mechanism of which may be involved in the inhibition of Cx43 gap junction.