Polyadenylated messenger RNA in paired helical filament-immunoreactive neurons in Alzheimer disease.

An antibody raised against isolated paired helical filaments (PHF) was used to identify tangle-bearing (PHF+) neurons in autopsy brain tissue from six Alzheimer disease (AD) patients and six age-matched controls (AMC). A comparison of the levels of polyadenylated messenger RNA [poly(A)+ mRNA] in PHF+ and PHF- neurons of similar cross-sectional area in temporal and parietal lobe and cerebellum from four AD and four AMC brains was made by analysis of in situ hybridization of [3H] polyuridylate [poly(U)] to intracellular poly(A)+ mRNA. In PHF+ neurons, the level of poly(A)+ mRNA was approximately two-thirds that in similar-sized PHF- neurons in either AD or AMC. The level of poly(A)+ mRNA in PHF- neurons in regions of the brain that have more of the histopathologically defined effect in AD was similar to that in regions with less effects.