An electron microscopic examination of age-related changes in the rat liver. The influence of diet.
The influence of age and diet on the ultrastructure of hepatocytes is reported. The following dietary manipulations were investigated: Group 1, fed ad libitum a diet containing 21% protein; Group 2, fed a similar diet but restricted to 60% of the intake of Group 1 from 6 weeks of age onwards; Group 3, restricted from 6 weeks to 6 months of age and thereafter fed ad libitum; Group 4, restriction started at 6 months of age; Group 5, fed ad libitum a diet containing 12.6% protein. In all groups the size of hepatocytes was found not to increase during adult life. The size of hepatocytes in Groups 2 and 4 was the same as or larger than that of the other groups; thus food restriction resulted in a decreased number of hepatocytes. Changes in the structure of some organelles and the accumulation of lipofuscin granules occurred with advancing age and the extent of these age-related changes was less in Groups 2 and 4 than in the other groups. These morphologic findings in conjunction with our previously reported metabolic findings provide a new view of the action of food restriction on the aging process.
Iwasaki
K
K
Department of Pathology, Nagasaki University School of Medicine, Japan.
Maeda
H
H
Shimokawa
I
I
Hayashida
M
M
Yu
B P
BP
Masoro
E J
EJ
Ikeda
T
T
D000375:Aging / Q000502:physiology*; D000818:Animals; D004032:Diet; D008099:Liver / Q000648:ultrastructure*; D008297:Male; D008854:Microscopy, Electron; D051381:Rats; D011916:Rats, Inbred F344