Temporal changes of cerebral metabolites and striatal lesions in acute 3-nitropropionic acid intoxication in the rat

To investigate the mechanisms of neuronal death in neurodegeneration, in vivo localized proton magnetic resonance spectroscopy ((1)H-MRS) and diffusion-weighted MRI (DWI) were used to evaluate temporal changes in rat striata after administration of 3-nitropropionic acid. It was found that N-acetylaspartate (NAA) reduction, with nearly simultaneous evidence of striatal lesions in DWI, was preceded by a significant and progressive increase of acetate. Shortly before the NAA levels decreased to the lowest point, acetate levels peaked and began to gradually decline toward the control levels. These results suggest that acetate increase may arise from fatty acid degradation, inhibition of succinate dehydrogenase and possible NAA hydrolysis. The elevated acetate may provide a source of acetyl group for membrane repair during excitotoxic brain injury. Magn Reson Med 44:29-34, 2000.