CEREBROSPINAL-FLUID CONCENTRATIONS OF SOLUBLE AMYLOID BETA-PROTEIN AND APOLIPOPROTEIN-E IN PATIENTS WITH ALZHEIMERS-DISEASE - CORRELATIONS WITH AMYLOID LOAD IN THE BRAIN

Objective: To compare soluble amyloid beta-protein and apolipoprotein E levels in cerebrospinal fluid (CSF) and brain extracts from patients with definite Alzheimer's disease. Setting: University medical center . Patients: Nineteen patients with definite Alzheimer's disease. Main Outcome Measures: Soluble amyloid beta-protein and apolipoprotein E le vels in CSF, in neutral and low-pH brain extracts, and in formic acid- treated sections of the frontal, temporal, and cerebellar cortices, me asured using enzyme-linked immunosorbent assay. Results: Soluble amylo id beta-protein and apolipoprotein E levels in CF were significantly l ower in patients with congophilic angiopathy than in those without ang iopathy. The levels did not correlate with the number of amyloid plaqu es in the neocortex. There was, however, a tendency toward an inverse correlation between the amount of amyloid beta-protein in the frontal cortex extracts and the soluble amyloid beta-protein level in CSF. Con clusion: Soluble amyloid beta-protein levels in CSF may reflect amyloi d accumulation in brain blood vessels.