Pathology of Alzheimer's disease.

The fundamental pathophysiology of Alzheimer's disease remains poorly understood, but progress has been dramatic in description of the pathology at the molecular level. The characteristic Alzheimer amyloid derives, in part, by action of microglia, from a precursor protein that is well characterized at the protein and gene levels. The characteristic paired helical filaments contain phosphorylated tau proteins and perhaps other constituents. At the neurotransmitter level, Alzheimer's disease involves not only loss of cholinergic cells but of serotonergic and other neurotransmitter systems as well. Damage to mitochondria may play an important role in precipitating the cellular pathophysiology.