Table 1.
Number of animals showing seizures or interictal spikes, and average seizure duration.
Fig 1.
EEG recording of an SLV326 induced convulsive seizure.
Such generalized seizures were found in 6 out of 24 Wistar rats treated with SLV326. Control animals were seizure free. Seizures typically start with low amplitude spikes that gradually increase in amplitude. The duration of this seizure (a.) is 30 seconds. High amplitude spike activity can be seen during the whole seizure (b.). The seizures of 3 out of 6 animals were followed by a postictal depression (c.). Behaviorally this EEG corresponds with severe tonic-clonic convulsions, Racine scale 5 (S1 File).
Fig 2.
Examples of interictal spikes from a SLV326 (left) and a control animal (right).
An average of 65 spikes per hour was found in 9 out of 24 SLV treated animals, versus 1 control animal out of 11 having 16 spikes per hour. Interictal spikes in the SLV group were all visible on all 3 EEG channels (left), whereas the spikes in the control animal were local, on the cortex (right).
Fig 3.
Frequency spectra of background EEG in active and passive states.
Areas of interest, determined on the basis of t-profiles, are marked in grey. During activity (left side) there are clear theta peaks in SLV326 treated animals as well as controls, with a significantly lower frequency of the theta peak compared to that of the controls. Also, a decrease in relative gamma power is noticeable during activity. No such differences are present in the passive spectra.
Fig 4.
Total relative power for the theta (left) and gamma (right) areas of interest.
No differences in theta power were observed, 27.9% (SD 8.62) for SLV versus 24.7% (SD 6.87) for controls. There was however a significant treatment-state interaction in the gamma range, (F(1,33) = 22.9, p< 0.001). In the active state a treatment effect was observed, as total relative power in SLV treated is significantly lower (p < .05) than in control animals, 9.45% (SD 4.25), compared to 16.8% (SD 7.86). No such shift in relative power was found in the passive state. Mean and SD are given.