Local Disappearance of Epiphyseal Growth Plates in Rats with Hypervitaminosis A

Tetsuo KODAKA, Hisashi TAKAKI, Satoshi SOETA, Ryoichi MORI, Yoshihisa NAITO
1998 Journal of Veterinary Medical Science  
Epiphyseal growth plates of proximal tibiae in rats with high doses of vitamin A (V-A) were observed. Of 4 groups, each consisting of 5 rats, three groups were given V-A at doses, IU/100 g by body weight/day, of 50,000, 100,000, and 150,000, respectively. The other group rats were given no V-A (control). Rats were administered V-A for the 5 days from 4 weeks after birth and sacrificed at 12 weeks after birth. Three rats of the 150,000 IU group died during the period of observation. The
more » ... ation. The decalcified sections were stained with hematoxylin-eosin or toluidine blue. In the ground sections, microradiography, backscattered electron imaging, and energy-dispersive Xray microanalysis were performed. These observations suggest that the local disappearance of epiphyseal growth plates under high doses of V-A goes in the order of the increased doses through the process of (1) calcified cartilage areae appearing in the resting cell zone, (2) some of the calcified areae extending in the growth plate towards the diaphysial side, (3) bone tissue replacing the calcified areae, and (4) the local disappearing of the growth plate. Such a local disappearance may be formed in the stressed proximal regions of tibiae. -KEY WORDS: calcified cartilage, epiphyseal growth plate, hypervitaminosis A, local disappearance, sulfur content.
doi:10.1292/jvms.60.815 pmid:9713809 fatcat:ptnhxp7hmvexnishrnxnn5lsia