Effect of short-term physical stress on DNA and collagen synthesis in the femur of young and old mice.
Aging of long bone in the hindleg of the mouse is accompanied by a progressive cavitation of the cortical bone along with clear atrophic structural changes characteristic of senile osteopenia. Quantitative analysis indicates that there is a nonsignificant change in the DNA content, but an increase in the protein percentage of the total bone wet weight. Bones of old animals incorporate significantly less (3H)-thymidine and markedly less (3H)-proline. This study revealed that endurance training in old animals induced a significant increase in DNA and collagen synthesis, yet the overall wet weight of the corresponding bone decreased. It thus became apparent that the femur of old animals possesses the capacity to respond to enforced training, yet the latter contains elements characteristic of a negative type of adaptation.
D000375:Aging / Q000378:metabolism*; D000818:Animals; D003094:Collagen / Q000096:biosynthesis*; D004247:DNA / Q000096:biosynthesis*; D005260:Female; D005269:Femur / Q000033:anatomy & histology / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D009929:Organ Size; D010807:Physical Endurance; D005082:Physical Exertion; D013997:Time Factors
D003094:Collagen; D004247:DNA