Single microinjection of L-glutamate induces oxidative stress in discrete regions of rat brain.

Glutamate (Glu) is a major excitatory amino acid neurotransmitter in the mammalian brain. Under Certain Circumstances Glu can also exert toxic effects on neuronal Cells. To unravel the biochemical mechanisms of Glu-induced acute neuronal injury, Glu 1 mumol/1 mul was microinjected into cerebral Cortex, striatum and hippocampus of adult rats and oxidative stress and antioxidant parameters were evaluated. The results show that the rate of lipid peroxidation was significantly increased in the above brain regions following Glu administration suggesting neuronal membrane damage and also the total and free sulfhydryl groups were significantly depleted, indicating altered red-ox status of the cells. There was also alteration in the activity of antioxidant enzyme catalase in cerebral cortex. Some of the above Glu-induced effects were reversed or modified by NMDA receptor antagonist MK-801.