RESUMO
Mercury (Hg) is one of several elements that have been implicated in the etiology of a number of age-related neurological diseases. In our studies, Hg has been determined by instrumental neutron activation analysis (INAA) along with up to 20 other elements in samples of brain, hair, and nail from subjects with Alzheirners disease (AD), in samples of brain, spinal cord, nail, blood cells, and blood serum from subjects with amyotrophic lateral sclerosis (ALS), and in corresponding samples from age-matched, neurologically nomal control subjects. Control and AD brain temporal lobes were subjecled to subcellular fractionation by ultracentrifugation and fractions enriched in inuclei, mitochondria, and microsomes were then also analyzed by INAA. Our results from these studies, together with observations from recent related in vitro and animal model studies, are summarized in this chapter. From the data we have obtained, it is clear that significant Hg imbalances relative to control subjects do exist in both AD and ALS subjecis. However, additional studies are required to define the principal pathways for Hg entry into the central nervous system and the role of the observed imbalances in the etiology and pathogenesis of these diseases.