RARE NEUROPIL THREADS IN AMYOTROPHIC-LATERAL-SCLEROSIS AND PARKINSONISM-DEMENTIA ON GUAM AND IN THE KII PENINSULA OF JAPAN

Using three different silver impregnation methods and antisera against microtubule-associated protein-tau (MAP-tau) and amyloid beta/A4 prot ein, we demonstrated abundant neurofibrillary tangles (NFTs), rare sen ile plaques, absence of amyloid angiopathy and rare MAP-tau- and silve r-positive neuropil threads in the hippocampus of patients with amyotr ophic lateral sclerosis (ALS) and parkinsonism-dementia (PD) on Guam a nd in the Kii Peninsula of Japan. In contrast, abundant neuropil threa ds, NFTs, senile plaques with associated dystrophic neurites and amylo id angiopathy were confirmed in Alzheimer disease patients. These obse rvations indicate that there may be important factor(s) responsible fo r the difference in the deposition and distribution of amyloid beta/A4 protein and MAP-tau between Pacific ALS and PD and Alzheimer disease.