Therapeutic time window of low-frequency stimulation at entorhinal cortex for amygdaloid-kindling seizures in rats

The present study was designed to determine whether low-frequency stimulation (LFS) of the entorhinal cortex(EC) has an anticonvulsive effect, and whether LFS delivered at different times plays different roles. We found that LFS of the EC immediately or 4 s after kindling stimulation had an anticonvulsive effect, and that the latter had a better effect on both kindling and kindled seizures. However, LFS delivered after the cessation of afterdischarge or 10 s after the kindling stimulation, augmented the epileptic activity. So the EC is a potential target for LFS to interfere with epilepsy. Our findings suggest that even in the duration of afterdischarge, there exists a "time window" for LFS treatment, indicating that the time delay of closed-loop stimulation is crucial for LFS treatment.