Seizure Semiology in Rats with Post-traumatic Epilepsy
Abstract number :
3.19
Submission category :
3. Neurophysiology / 3F. Animal Studies
Year :
2022
Submission ID :
2204922
Source :
www.aesnet.org
Presentation date :
12/5/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:27 AM
Authors :
Pedro Andrade, – UEF; Robert Ciszek, MSc – UEF; Tomi Paananen, PhD – UEF; Xavier Ekolle Ndode-Ekane, PhD – UEF; Asla Pitkänen, MD, PhD, DSc – UEF
Rationale: The 5-stage Racine scale has been the key reference for describing the behavioural severity of induced and spontaneous seizures in rodents since 1972. Recent availability of video-electroencephalogram (vEEG) monitoring with high-resolution cage-specific cameras has made it possible to perform a more accurate analysis of behavioural correlates of electrographic seizures. In particular, the semiology of spontaneous seizures in rats with post-traumatic epilepsy induced by lateral fluid-percussion injury is only partially covered by the Racine scale. Here, we propose a novel description of seizure semiology which takes into account the onset, temporal evolution and awareness state.
Methods: Altogether 127 seizures in 8 male Sprague-Dawley rats with PTE were analysed. Rats were 24/7 vEEG monitored for 30 d during the sixth post-injury month for diagnosis of PTE. Each electrographic seizure was visually evaluated from time-locked high-resolution videos (30 fps, acA1300-75gm). Sleep/wake stage at seizure onset, seizure onset electrode and seizure duration were marked. Behavioural manifestations of unprovoked seizures included 62 different features, which are summarized in Table 1._x000D_
Results: The mean seizure duration was 92 s (range, 13-169 s). In 100% (8/8) rats, seizure onset occurred at sleep. On average, 21 (range, 4-38) seizure manifestations/rat were found. In 7/8 rats, seizure onset was followed-up by an arousal and immobility. In 6/8 rats, the next behavioural manifestations were confused exploration with sniffing followed by head clonus, left forepaw clonus and wet-dog shakes (WDS) during and/or after the seizure. No correlation was found between the seizure duration and the number of behavioural features.
Conclusions: We propose to expand the list of behavioural features beyond that of Racine’s scale to more accurately describe the behavioural manifestations of unprovoked electrographic seizures in rats with PTE. We hope that the revised seizure semiology will help to advance translational knowledge of rodent spontaneous seizures, understand their relationship with variable electroencephalographic patterns over the seizure evolution, and eventually, facilitate the evaluation of disease-modifying therapies.
Funding: Academy of Finland, Sigrid Juselius Foundation, NINDS U54 NS100064
Neurophysiology