Seizure number, cumulative duration, and EEG power attenuation in rats treated with phenobarbital and bumetanide.

<p>The number of hypoxia-induced seizures (A), and cumulative seizure duration (B) were plotted for each treatment group. Vehicle-treated rats (n = 38) averaged 11.8±0.7 seizures, with an average cumulative seizure duration of 229±16.3 s. Treatment with phenobarbital (pheno) reduced seizure incidence by approximately 50% (n = 33, 6.8±1.0, 122±20.8 s), but did not completely attenuate activity. The combination of phenobarbital and 0.15 mg/kg bumetanide (pheno +0.15 mg/kg BMX) reduced seizure incidence by approximately 75% compared to vehicles (n = 35, 3.8±0.9, 61.3±16.1 s), and was more effective than phenobarbital alone. The higher dose (pheno +0.3 mg/kg BMX) was even more effective, decreasing seizure activity by ∼85% from vehicles (n = 25, 1.6±0.6, 38.5±17.0 s), and ∼75% from phenobarbital. (C) FFT analysis revealed increased spectral power between 4–12 Hz during seizures (vehicle). The average summed power between 4–12 Hz was plotted for each treatment group. Treatment with phenobarbital (n = 5, 56.8±8.1 µV), bumetanide (low dose: n = 3, 45.84±7.4 µV; high dose: n = 5, 47.1±5.5 µV), and the combination of phenobarbital and low dose bumetanide (n = 3, 30.0±9.4 µV) had little effect on summed power at these frequencies. However, in rats treated with the high dose combination (n = 4, 24.6±3.0 µV) summed power was reduced to levels similar to pre-hypoxia baseline EEG recordings (control). Mean ± SEM. Error bars indicate SEM. *<i>p</i><0.05, **<i>p</i><0.01, ***<i>p</i><0.001.