No abstract

This study was designed to examine morphological changes in cross sections of the thoracic aorta of male Swiss albino mice during the course of aging. Histometric measurements made on the aortas of mice at 1, 3, 10 and 17.5 months of age showed that the tunica media, which consists of elastin lamellae and smooth muscle layers, thickens significantly with advancing age. To evaluate the effects of dietary restriction on the aorta, the aortas of 20 month old mice on a 4% protein diet (restricted) were compared with those on a 26% protein diet (control). The aortas of the 26% protein fed mice were significantly thicker and the number of elastin lamellae was significantly greater than those of the 4% protein fed mice. The control mice showed a greater degree of age related changes in the aorta than did mice on the protein restricted diet.