Amyloid β precursor protein-mRNA is expressed throughout cerebral vessel walls

To determine the presence and distribution of cerebrovascular A beta production we investigated amyloid beta precursor protein (A beta PP)-mRNA expression by RNA in situ hybridization in patients with hereditary cerebral hemorrhage with amyloidosis, Dutch type, Alzheimer disease and controls. In all subjects, A beta PP-mRNA was expressed in endothelial cells, smooth muscle cells, adventitial cells and brain pericytes and/or perivascular cells. Meningeal cells also expressed A beta PP-mRNA. A beta PP was detected in endothelial cells, smooth muscle cells and adventitial cells. The demonstration of A beta PP-mRNA at all vascular sites where amyloid formation can occur supports an important contribution of locally derived A beta to cerebrovascular amyloidosis. (C) 1999 Elsevier Science B.V. All rights reserved.