@article{oai:omu.repo.nii.ac.jp:00009561, author = {ARAKAWA, Akira and HASHIMOTO, Yoshiyuki}, journal = {Bulletin of the University of Osaka Prefecture. Ser. B, Agriculture and biology}, month = {Dec}, note = {application/pdf, The present study was undertaken in order to clarify histological age changes in the femur of the mouse with special reference to the appearance of ossification centers and the growth of the distal metaphysial region. Observation was performed using 140 mice of the bc strain ranging in age from the 16th day in fetal life to 336 days in postnatal life. Sections were prepared longitudinally as exactly as possible, being stained with hematoxylin and eosin. The presence of the thin perichondral bone plate and the ossification center in the diaphysis was already noticed as early as the 16th day in fetal age. On the other hand, the formation of the ossification center in the distal epiphysis was observed to begin on 5 days after birth. During the course of development of the epiphysial ossificafion, the epiphysial plate was found to consist of three layers, a) resting cartilage cells, b) proliferating cartilage cells and c) hypertrophic cartilage cells. On 15 and 20 days of postnatal age, the epiphysial plate showed a maximum in width and decreased afterward. Although the resting cartilage cells disappeared on the stage of 60 days and the other cartilage cellular elements in the plate decreased in number progressively from this stage onward, even on 336 days, a time when was the final stage of the observation, afew cartilage cells were still seen remaining and the perforation of the epiphysial plate by the medullary cavity was still not found to occur. Alizarin red S stain, roentogenologic and histological methods have been extensively applied to the study of bone, and recently WIRTSCHAFTER ('60) published an atlas entitled "Genesis of mouse skeleton" in which the former two methods were employed. Studies on normal age changes of bones by the use of histological method have already been made in mice (CHEN '52; SILBERBERG and SILBERBERG '41; ZORZOLI '48) as well as in rats. These studies, however, have been based on the observation of specimens obtained mainly from the tibia and sternum in mice, and there are some differences in the rate of skeletal growth in different bones. In contrast to the extensive literature on the femur of the rat which was reviewed by PRATT ('57; '59) little attention has been paid to that of the mouse especially in relation to its histological age changes. Now, the present study was undertaken in order to clarify histological age changes in the femur with attention to the appearance of ossification centers and the growth of the distal metaphysial region., Bulletin of the University of Osaka Prefecture. Ser. B, Agriculture and biology. 1961, 12, p.65-72}, pages = {65--72}, title = {Histological Studies on the Developing Femur of the Male Mouse}, volume = {12}, year = {1961} }