Effects of l-azetidine-2-carboxylic acid, a proline analogue, on the in vitro development of mouse tooth germs

Abstract

Incisor and molar tooth germs from 14- and 15-day-old mouse embryos were cultured on agar-solidified Eagle's basal medium. Such tooth germs showed typical histo- and cytodifferentiation during the 8-day culture period. However, development of tooth germs cultured on medium containing l-azetidine was suppressed. In the experimental cultures, some germs displayed slight regression and disorganization whereas others were merely arrested at the se of development at the time of explanation. On the other hand, tooth germs cultured on medium containing l-azetidine in combination with proline developed normally. Suppressed tooth germs which were removed from medium containing l-azetidine and placed on control medium or proline-rich medium resumed development, so that their stage of differentiation was equivalent to that of controls at the termination of the culture period. These results support the notion that the collagen component of the extracellular matrix influences epithelial-mesenchymal inductive interactions.