Influence of G protein-coupled estrogen receptor 1 in epilepsy susceptibility of temporal lobe epileptic rats / 中华神经医学杂志

ABSTRACT

Objective:To study the influence of G protein-coupled estrogen receptor 1 (GPER1) specific agonist G1 and antagonist G2 in epilepsy susceptibility of temporal lobe epileptic rats.Methods:Sixty rats were randomly divided into control group, G1 treatment group and G15 treatment group ( n=20). Rats in the latter two groups were intraperitoneally injected with GPER1 agonist G1 (10 μg) or antagonist G15 (40 μg) for a consecutive 12 d. Lithium chloride pilocarpine epilepsy models were prepared in the 3 groups. The behavior manifestations of these rats were observed within 1 h of intraperitoneal injection of pilocarpine; Racine grading was used to evaluate the severity of epileptic seizures every 5 min; the latency of epileptic seizures (Racine grading IV) and epileptic seizure grading at different time points in the 3 groups were compared. The EEG monitoring was performed to these rats, and EEG data were recorded from 10 min before pilocarpine injection to 2 h after pilocarpine injection; EEG time-frequency was analyzed by Fast-Fourier transform (FFT); distribution of brain electrical energy and changes of θ and α wave energy during 20 min of epileptic status were compared among the 3 groups. Results:(1) As compared with that in the control group and G1 treatment group, the latency of epileptic seizures in the G15 treatment group was significantly shortened ( P<0.05); 15 and 20 min after pilocarpine injection, the epileptic seizure grading of rats in G1 treatment group was statistically lower than that in control group ( P<0.05); 15-35 min after pilocarpine injection, the epileptic seizure grading of rats in G15 treatment group was significantly higher than that in control group ( P<0.05). (2) As compared with those in the control group, rats in the G1 treatment group had smaller brain wave amplitude, while the rats in the G15 treatment group had earlier seizure time, larger brain wave amplitude and higher frequency. There were no obvious changes in the amount of brain electrical energy between the G1 treatment group and control group; while the amount of brain electrical energy in the G15 treatment group 2 h after pilocarpine injection was higher than that in the control group. As compared with those in the control group and G1 treatment group, the θ and α wave energy values of rats in the G15 treatment group were significantly increased within 20 min of epileptic status ( P<0.05). Conclusion:Activation level of GPER1 might be associated with susceptibility to epileptic seizures, and specific inhibition of GPER1 activation can enhance the susceptibility to epilepsy and increase the energy values of specific frequency bands during epilepsy.