Histomorphometry and autoradiography of cultured fetal rat long bones

Authors

  • Dr. Jean-Raphael Nefussi,

    Corresponding author
    1. Departments of Medicine and Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510
    • c/o Dr. R. Baron, Department of Internal Medicinen, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510
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  • Agnes Vignery,

    1. Departments of Medicine and Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510
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  • J. Edward Puzas,

    1. Department of Orthopedics, University of Rochester School of Medicine, Rochester, New York 14642
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  • Dr. Roland Baron

    1. Departments of Medicine and Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510
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Abstract

The behavior of fetal rat long bones cultured in vitro according to Raisz's technique (1969) was studied by histomorphometry and autoradiography for a period of four days. The changes were recorded daily both on the trabecular and cortical bone by measuring the bone volume, the number of osteoclasts, and the number of nuclei per osteoclast. Radioactive calcium release was measured and compared to the changes in bone volume and in the number of osteoclasts. An autoradiographic study, using 3H-proline and 3H-thymidine in flash labeling in the medium and 3H-thymidine in follow-up labeling after one injection in vivo was performed to evaluate the bone formation, the cellular proliferation rate and cell differentiation. After four days in culture, an increase in total calcified bone volume was observed which correlatd with changes in the trabecular bone. No significant changes were recorded in the cortical bone. The results showed a good maintenance of the resorption and formation phenomena through an active process of cellular multiplication and differentiation. Undifferentiated cells were labeled in flash label and osteoblast, osteocyte and some osteoclast nuclei were labeled in follow-up studies.

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