Ethanol suppressed seizures in lindane-treated rats. Electroencephalographic and behavioral studies

This study examines the effects of ethanol on lindane-induced seizures in rats. The animals were divided into following groups: 1. saline, 2. DMSO (dimethylsulfoxide), 3. lindane dissolved in DMSO in the dose of 4, 6 or 8 mg/kg (L(4), L(6) and L(8) groups, respectively), 4. ethanol 2 g/kg administered 30 min prior to lindane (protected groups AL(4), AL(6) and AL(8)) and 5. ethanol alone (2 g/kg). In order to determine ethanol concentration in plasma, blood samples were collected by cardiac puncture 30 and 60 min after ethanol injection. For EEG and power spectra recordings, electrodes were implanted into the skull. The lindane treatment resulted in a dose-dependent increase of seizure incidence and severity. The rats displayed severe seizure patterns characterized by high voltage spike-wave complexes, poly-spikes and sleep-like patterns in EEG, while the power spectra were intensively elevated in comparison to the corresponding controls. Ethanol alone led to increased EEG power spectra, which became dominant in the range of 0-4 Hz. For evaluation of anticonvulsant ethanol action we compared latency to seizure, incidence and seizure severity (scale from 0 to 4) in the examined groups. Ethanol diminished seizure incidence in AL(4) and AL(6) groups, decreased intensity of convulsions, and prolonged duration of latency period in AL(8) group. We observed suppression of the EEG signs of lindane-provoked epileptiform activity in AL(4) and AL(6), but not in AL(8) group. These results suggest that ethanol acted protectively on lindane-induced seizures and suppressed behavioral and epileptic EEG spiking activity.