Clomipramine increases the incidence and duration of spike-wave discharges in freely moving WAG/Rij rats

SummaryPurposeThe noradrenergic and serotonergic system may have a role in modulation of absence seizures. We investigated whether the single injection of monoamine reuptake inhibitor clomipramine has an acute effect on spike-wave discharge (SWD) activity in Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats.MethodsWe injected a single dose of 20 or 50 mg/kg clomipramine intraperitoneally into WAG/Rij rats and measured the incidence and duration of SWD episodes for 4 h after injection. The changes in SWDs were compared to the preceding 5-day average control level.ResultsThe 20 mg/kg clomipramine significantly increased the incidence of SWDs in the first measured hour while the 50 mg/kg dose significantly increased the incidence and duration of SWDs in the whole measured 4-h period.ConclusionsClomipramine, by acutely elevating synaptic monoamine levels, could exacerbate absence seizures.