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

To determine the presence and distribution of cerebrovascular A beta produc tion we investigated amyloid beta precursor protein (A beta PP)-mRNA expres sion by RNA in situ hybridization in patients with hereditary cerebral hemo rrhage 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. Me ningeal cells also expressed A beta PP-mRNA. A beta PP was detected in endo thelial 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 cerebrovasc ular amyloidosis. (C) 1999 Elsevier Science B.V. All rights reserved.