Expression of the neural cell adhesion molecule (NCAM) in Alzheimer's disease.

Expression of the nerve cell adhesion molecule, NCAM, was examined in post-mortem brain samples from patients with Alzheimer's disease (AD) and from age-matched controls. Four major isoforms of NCAM were identified by Western blot analysis 195, 185, 145 and 120 kDa with no differences being observed in either the intensity of individual band staining or in the expression of the constituent NCAM isoforms in AD when compared with controls. Immunohistochemical staining revealed star-shaped NCAM-positive structures with numerous radiating 'processes' or a more protoplasmic shape with short and thick 'processes'. These structures were not obviously more abundant in AD and there was no NCAM immunoreactivity in neuritic plaques or neurofibrillary tangles. This evidence suggests there is no change in NCAM expression in AD.