Atherosclerosis is a disease mainly of large, high pressure arteries and of valves, typically sparing veins and small, low pressure arteries. We investigate the resistances of the vena cava and the pulmonary artery to the flow of water and the infiltration of solutes into the vessel walls and compare them with similar processes in the aorta. The goal is to see if differences in macromolecular transport from the blood into the vessel wall amongst vessels can explain their different susceptibilities to atherosclerosis.