Seizure Induction and Monitoring in Rodents

Animals were given LiCl (3 mEq/kg, i.p) 24 h before the pilocarpine treatment. To reduce the peripheral effects of pilocarpine, atropine methylbromide (5 mg/kg, i.p.) was also received 20 min before the pilocarpine treatment. To induce SE, animals were treated with pilocarpine (30 mg/kg, i.p.). Control animals received saline in place of pilocarpine. For evaluation of the effect of siRNA knockdown on seizure susceptibility in response to LiCl-pilocarpine, animals were recorded EEG signals with a DAM 80 differential amplifier (0.1–3000 Hz bandpass; World Precision Instruments, Sarasota, FL, USA). EEG activity was measured during the 2 h recording session from each animal. The data were digitized (400 Hz) and analyzed using LabChart Pro v7 (AD Instruments, Bella Vista, NSW, Australia). Time of seizure onset was defined as the time point showing paroxysmal depolarizing shift, which lasted more than 3 s and consisted of a rhythmic discharge between 4 and 10 Hz with amplitude of at least two times higher than the baseline EEG (Kim and Kang, 2011 (link)). EEG activity was measured during the 2 h recording session from each animal. Spectrograms were also automatically calculated using a Hanning sliding window with 50% overlap. Two hours after SE onset, diazepam (Valium; Roche, France; 10 mg/kg, i.p.) was administered and repeated, as needed.