Summary
Alterations in cross-sectional area and shape of the femur of female Sprague-Dawley rats exposed continuously for 810 days to either 2.76 or 4.15 G by centrifugation were studied. Compared with control animals, chronically centrifuged rats showed on the average a smaller body-weight (19.3 and 29.1%), a smaller length of the femur (6.6 and 9.0%), and a smaller cross-sectional area at the midshaft position of the femur (15.1 and 19.1%). It was shown by analysis of covariance that chronic centrifugation at 2.76 and 4.15 G inhibits the longitudinal growth of the femur by the same amount as the overall growth in linear dimensions of the rat. The cross-sectional area of the femur at the midshaft position was the same at earth gravity and at hypergravity, if the comparison was made between animals of the same age and the same overall body-size. However, the shape of the femoral cross-section was altered by centrifugation; the sagittal diameter was increased whereas the frontal diameter was decreased.
It was shown that the experiments conducted to date have not given clear evidence of a direct relationship between cross-sectional area of the femur and the G load imposed on animals subjected to chronic centrifugation. The alterations in cross-sectional shape of the bones in the centrifuged animals are likely due to an immobilization effect caused by centrifugation.
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References
Allison, N., Brooks, B.: An experimental study of the changes in bone which result from non-use. Surg. Gynec. Obstet. 33, 250–260 (1921).
Amtmann, E.: Mechanical stress, functional adaptation and the variation structure of the human femur diaphysis. Ergebn. Anat. Entwickl.-Gesch. 44, 1–89 (1971).
Briney, S. R., Wunder, C. C.: Growth of hamsters during continual centrifugation. Amer. J. Physiol. 202, 461–464 (1962).
Burton, R. R., Besch, E. L., Sluka, S. J., Smith, A. H.: Differential effect of chronic acceleration upon skeletal muscles. J. appl. Physiol. 23, 80–84 (1967).
Carey, E.: Studies in the dynamics of histogenesis. Radiology 13, 127–168 (1929).
Casey, H. W.: The influence of chronic acceleration on the effects of whole body irradiation in rats. Doctoral Thesis, Univ. Calf., Davis (1965).
Engström, A., Amprino, R.: X-ray diffraction and X-ray absorption studies of immobilized bones. Experientia (Basel) 6, 267–276 (1950).
Gillespie, J. A.: The nature of bone changes associated with nerve injuries and disuse. J. Bone Jt Surg. B 36, 464–473 (1954).
Jankovich, J. P.: Structural development of bone in the rat under earth gravity, simulated weightlessness, hypergravity and mechanical vibration. NASA Contractor Report 1823. National Technical Information Service, Springfield, Virginia (1971).
Keil, L. C.: Changes in growth and body composition of mice exposed to chronic centrifugation. Growth 33, 83–88 (1969).
Oyama, J.: Reproduction and growth of mice and rats under conditions of simulated increased gravity. Amer. J. Physiol. 212, 164–166 (1967).
Oyama, J., Platt: Effect of prolonged centrifugation on growth and organ development of rats. Amer. J. Physiol. 209, 611–615 (1965).
Oyama, J., Zeitman, B.: Tissue composition of rats exposed to chronic centrifugation. Amer. J. Physiol. 213, 1305–1310 (1967).
Smith, A. H.: Chronic acceleration. In: Burton, R. R., T. Hoshizaki, C. F. Kelley, A. H. Smith, and I. H. Wagman, Principles of gravitational biology, vol. 9 of Space biology and medicine. Bioscience Programs Division of NASA (in press).
Smith, A. H., Kelly, C. F.: Influence of chronic acceleration upon growth and body composition. Ann. N.Y. Acad. Sci. 110, 410–424 (1963).
Tulloh, N. M., Romberg, B.: An effect of gravity on bone development in lambs. Nature (Lond.) 200, 438–439 (1963).
Vigliani, F.: Accrescimento e rinnovamento strutturale della compatta in ossa sottratte alle sollecitazioni meccaniche. Nota I. Ricerche sperimentali nel cane. Z. Zellforsch. 42, 59–76 (1955a).
Vigliani, F.: Accrescimento e rinnovamento strutturale della compatta in ossa sottratte alle sollecitazioni meccaniche. Nota II. Ricerche sperimentali nel cane. Z. Zellforsch. 43 17–47 (1955a).
Vigliani, F.: Evolution des greffes osseuses soumises experimentalement à des charges mécaniques continues. Xe Congr. de la Sociéte Internat. de Chirurgie Orthopédique et de Tramatologie. Bruxelles: Impr. des Sciences 1966.
Wunder, C. C.: The effects of chronic acceleration of animals: a commentary, p. 389–411. In: A. Gordon and M. J. Cohen, Gravity and the organism. Chicago and London: Chicago University Press 1971.
Wunder, C. C., Briney, S. R., Karl, M., Skaugstad, C.: Growth of mouse femurs during continual centrifugation. Nature (Lond.) 188, 151–152 (1960).
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Portions of this investigation were done while this author was a NASA-NRC Senior postdoctoral Research Fellow at Ames Research Center.
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Amtmann, E., Oyama, J. Changes in functional construction of bone in rats under conditions of simulated increased gravity. Z. Anat. Entwickl. Gesch. 139, 307–318 (1973). https://doi.org/10.1007/BF00519970
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DOI: https://doi.org/10.1007/BF00519970