Enhancement by food restriction of liver protein synthesis in the aging Fischer 344 rat.
Age-related changes in liver protein synthesis of ad libitum fed and food-restricted SPF Fischer 344 rats have been measured. In ad libitum fed animals, valine incorporation increased from 3 to 6 mo of age, decreased to the 3-mo level at 12 mo, remained relatively constant through 18 mo, and then declined further at 24 mo of age. By 24 mo valine incorporation was 30% of the 6-mo value. Food restriction had no effect at 3 mo of age (6 wk of restriction) but at 6 mo the rate of valine incorporation was 35% greater than the control, an increment that was maintained throughout the life of the animal. Therefore, although food restriction does not prevent the age-related decline in protein synthesis, it does maintain the rate of liver valine incorporation at levels greater than those observed in the liver of the ad libitum fed animal.
Ward
W F
WF
Department of Physiology, University of Texas Health Science Center, San Antonio.
D000367:Age Factors; D000375:Aging; D000818:Animals; D001835:Body Weight; D004032:Diet; D008099:Liver / Q000033:anatomy & histology / Q000378:metabolism*; D008297:Male; D009929:Organ Size; D014176:Protein Biosynthesis; D051381:Rats; D011916:Rats, Inbred F344; D014633:Valine / Q000378:metabolism
D014633:Valine