Citrus flavonoid improves MK-801-induced locomotive hyperactivity: Possible relevance to schizophrenia

Enhanced dopaminergic activity in rodents has been shown to lead to locomotor hyperactivity. MK-801, an NMDA (N-methyl-d-aspartate) receptor antagonist, indirectly activates dopaminergic activity in humans and rodents, and has the ability to induce locomotor hyperactivity. Abnormalities in locomotor activity are a prominent feature in the positive symptoms of schizophrenia. We showed here that the citrus flavonoid 3,5,6,7,8,3′,4′-heptamethoxyflavone (HMF) has a protective effect on hyperactivity induced by MK-801 in the Y-maze test and open field test. These results suggest that HMF has the ability to relieve MK-801-induced schizophrenia positive symptom-like behavior.