Impaired peripheral endothelial microvascular responsiveness in Alzheimer's disease

Abstract

Background: The concept that the neurotoxicity of amyloid β protein could partly result from vascular effects that may be detected in peripheral microcirculation is new. Methods: We compared peripheral endothelial vascular responses of patients with early clinically confirmed Alzheimer's disease (AD) to that of people with normal cognition and those with other forms of dementia. Acetylcholine (ACh) was iontophoresed into the skin and the resultant vasodilator response was measured using laser Doppler flowmetery. Results: The ratio of ACh response to saline (ratio E/S) was determined. Mean ± SEM of ratios E/S were 8.8 ± 0.9 for controls (n=168), 1.4 ± 0.1 for AD patients (n=80) and 3.1 ± 0.5 ..