Studies of Qingyangshen (II): modulatory effect of co-treatment with qingyangshen and diphenylhydantoin sodium on rat hippocampal c-fos expression during seizures.

We have reported that, after KA treatment in rats, there was first a significant increase in hippocampal c-fos expression during acute seizures and then a long-term inhibition in hippocampal c-fos expression during chronic seizures. In this experiment, we examined the modulatory effect of Qingyangshen (QYS), a traditional Chinese medicine with antiepileptic property, and diphenylhydantoin sodium (DPH) on hippocampal c-fos expression during seizures. We found that after intraperitoneal injection of QYS + DPH (15 mg/kg and 50 mg/kg respectively, q.o.d. x 6), the peak level of hippocampal c-fos mRNA induction during KA-induced acute seizures was reduced by 56.27%; while the inhibition of hippocampal c-fos expression during KA-induced chronic seizures was disinhibited to control level. It is suggested that the inhibitory effect of QYS + DPH on KA-induced seizures, chronic seizures in particular, may have much to do with its modulatory effect on hippocampal c-fos expression.