Acetylcarnitine reduces the immobility of rats in a despair test (constrained swim).

Male rats forced to swim in a cylinder adopted an immobile posture. Immobility was reduced by acetylcarnitine (5, 10, and 20 mg/kg) and by antidepressant drugs, such as desipramine and iproniazid, injected 24, 5, and, again, 1 h prior to behavioral testing. Acetylcarnitine also potentiated the anti-immobility effect of antidepressant drugs in the despair test. Chronic (10 days) treatment with acetylcarnitine mimicked the effect found after acute administration. It is possible that the action of the acetylcarnitine on the despair test is indicative of an antidepressant activity of this drug that is dependent on a change in the sensitivity of monoamine receptors in the brain.