In-vitro study of the cellular control of 18F uptake in the enamel of developing rat molar teeth

Abstract

Molar expiants from 6-day-old rats were cultured for 4 h in medium containing approx. 2μCi/ml 18F. Control-cultured expiants were compared to their contralateral pairs which had been subjected to: (1) the enamel organ removed prior to incubation; (2) the expiants heat-treated (65 °C for 10 min); or (3) a metabolic inhibitor, 5mM dinitrophenol (DNP), added to the medium. The Ca concentration of the medium indicated that the expiants became mineralized during incubation. Both removal of enamel organ and heat-treatment enhanced uptake of 18F from the medium. DNP had no consistent effect. As the pattern of 18F uptake was similar to that for net Ca uptake by mineralizing enamel, the findings suggest that there is no direct cellular control of F − flux through the enamel organ during the secretory phase of enamel formation.