Abstract
Effects of co-administration with the 5-HT2 receptor antagonist LY 53857 and the antidepressant mianserin on immobility time in the forced swimming test were investigated in mice. Mianserin did not affect the immobility time at ranges from 1—10 mg/kg, although it elicited anti-immobility effects at 20 mg/kg. Co-administration of the 5-HT2 receptor antagonist LY 53857 and a subactive dose of mianserin induced apparent anti-immobility effects. Since mianserin facilitates noradrenaline (NA) release from nerve terminals via inhibition of α2 receptors, the blockade of the 5-HT2 receptor may increase the antidepressant effect of drugs modifying NA levels in the synaptic cleft.
