The effects of melatonin in glutamate-induced neurotoxicity of rat cerebellar granular cell culture.

In the present study, melatonin was tested in subsequent doses in glutamate induced neurotoxicity in cerebellar granular cell culture of rat pups. Glutamate at 10(-7) M was found to induce neuronal cell death. The dead cell score was 2.75+/-0.7 in the control, while it was found to be 35.12+/-1.8 in the glutamate-administered group (P<0.0001). Melatonin very potently blocked glutamate neurotoxicity at all doses tested, with 10(-3) M, the highest dose tested, being the most effective. Glutamate may exert a neuroprotective effect by blocking one or more steps of the oxidation cascade in neurons and this effect may be blocked by melatonin.