ASTROCYTES ASSOCIATED WITH SENILE PLAQUES POSSESS MUSCARINIC ACETYLCHOLINE-RECEPTORS

AUTOPSY sections of the temporal and parahippocampal gyri were incubat ed with the monoclonal antibody M35 to label muscarinic acetylcholine receptors. Senile plaques were visualized either by counterstaining wi th Congo red or by Bielschowsky silver-stain of adjacent sections. The antibody labelled pyramidal and non-pyramidal cells in the grey matte r, as well as fibrous astrocytes in the white matter and first cortica l layer, of elderly control brains. In AD brains however, the grey mat ter was characterized by prominently labelled fibrous astrocytes and f ew or poorly labelled neurones. M35-immunoreactive astrocytes were oft en associated with senile plaques. These findings suggest that plaque- associated astrocytes may be responsive to acetylcholine or cholinergi c drugs.