POTENTIAL ANTIDEPRESSANT EFFECTS OF LEMON ODOR IN RATS

Antidepressant effects brought about by olfactory stimulation with var ious odorants were investigated with the forced swimming test, a relia ble means for screening antidepressant effects. Lemon odor significant ly reduced total immobility time and potentiated the imipramine-induce d reduction of total immobility time in the test. This synergistic eff ect of lemon odor and imipramine was not due to lemon odor decreasing the metabolism of imipramine. Lemon odor decreased locomotor activity in the open field, suggesting its effects to differ from those of psyc hostimulants but to be similar to those of antidepressants. The effect s of citral, which is one of the main components of lemon odor, were a s strong as those of lemon odor. The remaining odorants tested in this study failed to have any effects on total immobility time in the forc ed swimming test or on locomotor activity in the open field.