Effect of lamotrigine combined with felbamate on the horizontal (ambulatory) activity in mice

Exploratory and spontaneous locomotor activities, after administration of some novel antiepileptic drugs (felbamate and lamotrigine alone or in combination), were evaluated in mice by means of the electronically monitored locomotor activity system (Digiscan analyzer). Felbamate (injected intraperitoneally, at the single dose of 25.7 mg/kg) significantly reduced behavioral activity in terms of horizontal (ambulatory) activity in mice. The combination of felbamate (25.7 mg/kg) with lamotrigine (2.3 mg/kg) drastically reduced this parameter during the first 15-min period (habituation to a novel environment--being the rate of exploratory locomotor activity) and the second 15-min interval (spontaneous locomotor activity). Moreover, neither the exploratory, nor spontaneous locomotor activity of the mice, were affected by lamotrigine (at the separate dose of 2.3 mg/kg) with respect to the ambulatory activity of the animals tested. Felbamate administered alone or combined with lamotrigine considerably impaired exploratory and spontaneous locomotor activities of the animals tested in terms of horizontal activity.