Sub-convulsant dose of PTZ increases low-frequency EEG power at 5 Hz for several hours after administration.
 Normal waking EEG pre-dosing. Note peak in FFT record at 7-8 Hz corresponding to theta band.
 Diazepam (5 mg/kg) alone has little effect on EEG (27 min post dosing).
 This animal was treated with Vehicle, then 27 min later given PTZ (40 mg/kg). EEG recorded 26 min later shows periodic bursting which produced a significant increase in FFT amplitude at 5 Hz, distinct from theta EEG (note 5x decrease in FFT scale).
 Same animal as panel  also received PTZ at same time as animal in panel . In this case, Diazepam almost completely blocked PTZ-induced bursting.
Bursting induced by PTZ was quantified by frequency analysis, and the effect of Diazepam evaluated. Graph above shows significant effect of Diazepam (5 mg/kg) in suppressing PTZ-induced bursting (paradigm as in Figure 1; N= 5 / group). This paradigm potentially allows repeat testing of animals to determine the effects of chronic or sub-chronic administration of PTZ or anti-convulsant drug. *p<0.005.
Bursting can be induced in mice by dose-escalation of PTZ. The graph above shows the increase in EEG power at 4-6 Hz over a period of 280 min during successive administration of PTZ doses totaling 140 mg/kg. Diazepam (5 mg/kg) was then administered and within minutes suppressed the bursting.
Quantitative evaluation of bursting in mice and suppression by Diazepam (5 mg/kg). *p<0.05; ***p<0.001