SPARING OF NADPH-DIAPHORASE STRIATAL NEURONS IN PARKINSONS AND ALZHEIMERS DISEASES

THE free radical neuromodulator, nitric oxide (NO) has been implicated as a neurotoxin. Neurons containing NO synthase (NOS) also contain NA DPH-diaphorase (NADPH-d) and are resistant to NO toxicity. We report t hat NADPH-d-containing neurons within the striatum are spared in patie nts with Parkinson's (PD) and Alzheimer's disease (AD). However, a num ber of these neurons in both diseases appeared shrunken or bulbous wit h foreshortened dendritic processes. Quantitative analysis of cell are as revealed a significant difference only in the size of putamenal AD neurons which were decreased compared to normal controls. The possible involvement of NO in the neuropathogenesis of striatal derangement is discussed.