Ifenprodil is a novel
NMDA receptor antagonist that selectively inhibits receptors containing the NR2B subunit.
Lindane, a widely used
pesticide and scabicide, evokes
seizures mainly through the blockade of the
gamma-aminobutyric acid type A receptor complex. The aim of this study was to determine the effects of
ifenprodil on the behavioral and electroencephalographic (EEG) manifestations of
seizures in
lindane-treated rats. Adult male Wistar rats with three
electrodes implanted into the skull were treated intraperitoneally (i.p.) with
lindane 8 mg/kg and observed for seizure behavior and EEG during the next 30 min. Seizure behavior was assessed by incidence, severity (determined by a descriptive rating scale ranging from 0 to 4) and duration of latency. Increasing doses of
ifenprodil (5, 10, 20 mg/kg, i.p.) or vehicle were injected 30 min prior to
lindane administration.
Ifenprodil decreased the incidence and severity of
lindane seizures and prolonged the latency to
seizures in a dose-dependent manner. 20 mg/kg of
ifenprodil significantly decreased the incidence (p < 0.05) and severity (p < 0.05) of
seizures when compared to the vehicle treatment. Latency to
seizures was significantly prolonged by 10 and 20 mg/kg of
ifenprodil. The estimated ED(50) value of
ifenprodil was 15.53 (5.48-15.20) mg/kg. The
lindane-induced bursts of spiking activity in EEG were not completely suppressed by the applied doses of
ifenprodil. These results indicate that
ifenprodil alleviates behavioral
seizures and modifies EEG characteristics of
lindane seizures in rats, thus showing the involvement of
NMDA receptors containing the NR2B subunit in the mechanisms of
lindane convulsions.