Objective: To study the effect of the combined application of Rhei Radix et Rhizoma-Scutellariae Radix on the susceptibility of early epilepsy of traumatic brain injury in mice

in order to explore the mechanism of epilepsy after brain injury. Method: SPF-grade C57BL/6J male mice were randomly divided into 5 groups

namely blank control group

model group

low-dose Rhei Radix et Rhizoma-Scutellariae Radix treatment group (1 g·kg-1)

high-dose group (4 g·kg-1)

positive control group (2.6 g·kg-1 sodium valproate). A mouse model of closed brain injury was established by the weight-falling method in all test groups

except for the blank control group. The mice were given the corresponding drugs by gavage for successively 7 days after mice brain injury. Subacute dose of pentylenetetrazole (PTZ) was given to the mice after the last administration. The latency and mean seizure intensity of epileptic seizures in mice were measured through the behavioral observation. EEG changes of mice were analyzed by counting the sum of 0-20 Hz discharges. Positive cells of glial fibrillary acidic protein (GFAP) in hippocampal CA1 and CA3 regions were counted by immunohistochemistry. Protein expression of Na+-K+-2Cl- co-transporter (NKCC1) was detected by Western blot. Result: Compared with the control group

the latency of epilepsy seizure was significantly shortened in the model group

abnormal high-frequency discharge in brain was significantly enhanced

and the number of GFAP positive cells in the hippocampal CA1 and CA3 regions was significantly increased (P<0.05)

and the expression level of NKCC1 in neurons was remarkably increased (P<0.05). Compared with the model group

the low and high-dose Rhei Radix et Rhizoma-Scutellariae Radix could prolong the latency of epileptic seizures

reduce the abnormal discharge of brain

decrease the number of GFAP positive cells and the expression of NKCC1 protein in the hippocampus (P<0.05)

with significant difference between the high-dose group and the model group (P<0.05). Conclusion: The combined application of Rhei Radix et Rhizoma-Scutellariae Radix could reduce the susceptibility of early epilepsy after brain injury

and the mechanism may be related to the regulation of astrocytes.