APOLIPOPROTEIN-E EXPRESSION AT NEUROMUSCULAR-JUNCTIONS IN MOUSE, RAT AND HUMAN SKELETAL-MUSCLE

Apolipoprotein E (ApoE)-epsilon 4 allele has been associated with late onset familial Alzheimer's disease (AD). In both familial and sporadi c AD brain, ApoE is localized to the vessel walls, senile amyloid plaq ues, and neurofibrillary tangles. ApoE is also an 'injury-response' ma cromolecule in peripheral nerves and was reported to increase in respo nse to injury. We have demonstrated that Alzheimer beta-amyloid precur sor protein and a serpin alpha(1)-antichymotrypsin also found accumula ted in senile plaques in AD brain, were also localized at neuromuscula r junctions (NMJs). Using immunocytochemistry, our present results ind icate that ApoE is found in normal mouse, rat and human skeletal muscl e and concentrated at the NMJs as it is in the senile plaques in AD br ain. Such experiments may shed light on the mechanism of synapse loss, as well as plaque formation in this neurodegenerative disease.