APOLIPOPROTEIN-E (APOE) LEVELS IN BRAINS FROM ALZHEIMER-DISEASE PATIENTS AND CONTROLS

We measured apolipoprotein E (apoE) level in neutral and acidic pH ext racts of the frontal, temporal and cerebellar cortices from patients w ith definite Alzheimer's disease (AD) and controls, and analyzed the r elationship among apoE levels, clinical and neuropathological findings , and apoE genotype. Our data showed that the levels varied in differe nt brain regions being lowest in the frontal cortex and highest in the cerebellum in AD brains. ApoE levels in neutral pH extracts from the frontal cortex from AD patients were significantly lower than those of controls, and correlated negatively with the number of neurofibrillar y tangles. ApoE genotype was not associated with the levels of apoE. T here was no correlation between apoE levels and amyloid load or synapt ophysin-immunoreactivity in the brain. We conclude that apoE levels ar e not increased in AD brains. However, apoE levels vary in different b rain regions, and local factors related to the synthesis and metabolis m of apoE may be crucial in the pathogenesis of AD.