Genetic selection, general characterization, and histology of atherosclerosis-susceptible and -resistant Japanese quail.

A new animal model of atherosclerosis has been developed through genetic selection of Japanese quail (Coturnix coturnix japonica) into susceptible (SUS) and resistant (RES) lines. Characterization of the selected quail has shown that the RES birds were resistant to the disease and developed little atherosclerosis on a diet containing 1% cholesterol. The SUS birds were sensitive and developed severe atherosclerosis in 8-9 wks on a diet containing only 0.5% cholesterol. The histology of the progression of atherosclerosis in the SUS quail was studied. It bore a morphological similarity to that of human arterial atherosclerosis. The atherosclerotic plaque was characterized by intimal thickening, the presence of foam cells, the proliferation of smooth muscle cells and/or fibroblasts, and the formation of scar with collagen deposition. We believe that these two lines of quail may serve as a valid animal model for the study of the genetic and biochemical basis of cholesterol-induced atherosclerosis.