Diet-induced atrial endothelial damage--a scanning electron-microscopic study

A semipurified diet containing 28% fat (as lard), but no known atherogenic substances such as cholesterol, was fed to a group of Swiss stock mice. A group of similar mice was fed laboratory chow as controls. Within six weeks of diet feeding, experimental mice developed atrial thrombosis. In scattered areas of atria where thrombi were not present, the scanning electron microscope showed an endothelial response to the high-fat diet in the form of holes and crater-like lesions. In extreme cases, a whole endothelial cell might be almost totally destroyed. Clusters of leucocytes mixed with platelets and fibrin attached to the larger holes, suggesting the initiating mechanism of thrombogenesis, were also observed.