The effect of carbenoxolone on expression of GFAP and Cx43 in hippocampi of PTZ-kindled epileptic rats

Objectives To investigate the effect of carbenoxolone on astrocytes and its gap junction of PTZ-kindled rats.Methods Thirty adult male rats were randomly divided into normal saline(NS)group,PTZ-kindled(K)group,and CBX group,each group with 10 rats.NS group rats received intraperitoneal injection of NS only.The CBX group and K group rats were first treated with PTZ(i.p 35 mg/kg) to establish the epilepsy model of kindled rats.After kindling,the rats in both groups received CBX(10 mg/kg,CBX group)or NS(K group) for three days.The difference of seizure frequency among three groups was analyzed.The expression of GFAP-IR and Cx43 in hippocampi of the rats was examined with immunohistochemistry method.Results Spontaneous seizures occurred in PTZ-kindled epileptic rats.The frequency of seizure was less in the rats of CBX group than those in the K group.GFAP-IR astrocyte increased significantly in hippocampi of the rats in K group.In addition,hypertrophy of the cell body,increase of cell protrusions and Cx43 expression were found.However,there were no significant changes in GFAP-IR astrocytes(P 0.05),and the expression of Cx43 was decreased(P 0.05)in CBX group.Conclusions Carbenoxolone showed no effect in stimulating the proliferation of glias in PTZ-kindled rats,but it suppressed the Cx43 expression and epileptic activity.The study suggested that astrocyte and its gap junction played an important role in the development and aggravation of epilepsy.CBX might have potential anti-epileptic activity.