Ultrastructural changes in the comb and aorta of chicks fed excess testosterone

The mode of cellular response to testosterone was monitored in the combs and aortas of chicks with the aid of an electron microscope. A 7-week treatment of 30 mg of testosterone per day had little effect on plasma lipid metabolism. However, this treatment resulted in the activation of fibroblasts in the comb, activation of fibroblast-like and smooth muscle cells in the aorta, and degeneration of smooth muscle cells in the aorta. A treatment of 150 mg of testosterone per day for 7 weeks induced hyperlipidemia and lipid-rich aortic lesions. The abdominal aorta had more activated and degenerated smooth muscle cells, with or without stainable lipid droplets, than the ascending aorta.