[The role of matrix vesicles during development of the mineralizing tissues of tooth germ and craniofacial bone].
OBJECTIVE
To evaluate the role of matrix vesicles (MVs) during the development of mineralizing tissues.


METHODS
The ultrastructure of MVs of tooth germ, calvarial bone and mandibular bone were observed by transmission electron microscopy in fetal Wistar rat.


RESULTS
(1) The MVs were formed by osteoblast of the secret type, dentinoblast and process; (2) There was a mature process of the MVs in the extracellular matrix. The appearance of the hydroxyapatite (HAP) was a major mature feature; (3) HAP formed initially in the MVs entered into collage matrix and eventually mineralized; (4) The shifting sign of HAP from MVs to the surface of collage fibril was observed.


CONCLUSIONS
The MVs played an important role in the biomineralization, but the special arrange pattern of mature collage fiber provided a suitable environment and a model to the growth of HAP for further mineralization.
Zhu
P
P
Department of Oral Pathlology, School of Stomatology, Shanghai Second Medical University, Shanghai 200011, China.
Zhang
W
W
D000818:Animals; D001857:Bone Matrix / Q000502:physiology / Q000648:ultrastructure*; D002113:Calcification, Physiologic / Q000502:physiology*; D005147:Facial Bones / Q000254:growth & development / Q000648:ultrastructure*; D051381:Rats; D017208:Rats, Wistar; D014083:Tooth Germ / Q000254:growth & development / Q000648:ultrastructure*