Attenuation of the Post‐decapitation Convulsions after Repeated Treatment of Rats with Desipramine, Imipramine and Maprotiline

: The effects of repeated treatment of rats with the antidepressant or potential antidepressant agents alaproclate, citalopram, clomipramine, desipramine, imipramine, maprotiline, mianserin and zimeldine on the convulsions released by decapitation were examined. The noradrenaline uptake inhibitors desipramine, imipramine and maprotiline increased significantly the latency of onset of the post-decapitation convulsions (PDC's) after repeated administration of 10 μmol/kg orally twice daily, or 66 μmol/kg orally once daily (desipramine), for 15 days. The duration of the PDC's was slightly prolonged by these agents. A single acute dose of desipramine (20 mg/kg) administered at various time intervals before decapitation (1 to 24 hours) had no effect on the PDC's nor did repeated treatment with the other compounds examined, alaproclate, citalopram, clomipramine, mianserin and zimeldine, have any effect upon the PDC latency. The results are interpreted as evidence for noradrenaline receptor subsensitivity following chronic treatment.