earticle

영어

Schizophrenia is a severe mental disorder characterized by abnormal mental functioning and disruptive behaviors. Abnormal expression of N-methyl-D-aspartate (NMDA) receptor, one of the glutamate receptor subtypes, has also been suggested to contribute to the symptoms of schizophrenia. The effect of treadmill exercise on schizophrenia-in-duced apoptosis in relation with NMDA receptor has not been evaluat-ed. In the present study, we investigated the effect of treadmill exercise on neuronal apoptosis in the hippocampus using MK-801-induced schizophrenic mice. MK -801 was intraperitoneally injected once a day for 2 weeks. The mice in the exercise groups were forced to run on a treadmill exercise for 60 min, once a day for 2 weeks. In the present re-sults, repeated injection of the NMDA receptor antagonist MK-801 re-duced expression of NMDA receptor in hippocampal CA2-3 regions. MK-801 injection increased casapse-3 expression and enhanced cyto-chrome c release in the hippocampus. The ratio of Bax to Bcl-2 was high-er in the MK-801- induced schizophrenia mice than the normal mice. In contrast, treadmill exercise enhanced NMDA receptor expression, suppressed caspae-3 activation and cytochrome c release, and inhibited the ratio of Bax to Bcl-2. Based on present finding, we concluded that NMDA receptor hypofunctioning induced neuronal apoptosis in MK-801-induced schizophrenic mice. Treadmill exercise suppressed neuro-nal apoptosis through enhancing NMDA receptor expression in schizo-phrenic mice.