Low density lipoprotein receptor-related protein 1 (LRP1) is a type I membrane protein expressed in multiple cell types in the central nervous system including endothelial cells, vascular smooth muscle cells, pericytes, astrocytes, and neurons. LRP1 acts as an important efflux transporter of amyloid β-peptide 1-42 (Aβ42) across the blood-brain barrier from brain to blood. Expression of LRP1 and efflux of Aβ42 are both significantly decreased in Alzheimer’s Disease (AD) brain. LRP1 is oxidatively modified by the lipid peroxidation product 4-hydroxy-2-trans-nonenal (HNE) in AD hippocampus suggesting that Aβ42-mediated oxidative stress may result in oxidative modification of its own transporter decreasing the clearance of Aβ42 in AD brain. Exercise has been shown to increase the capacity of the brain to tolerate oxidation damage. In this study, the effect of acute voluntary exercise on expression and oxidative modification of LRP1 in brain of 5, 10, and 22 month old wild type mice was examined.