For the study on the effect of retinoic acid on the medial edge epithelial cells of fetal rat palate in vitro, the GD 15 fetal palatal shelves of Sprague-Dawley rats were cultured. Excised palatal shelves were placed on the milipore filter, and
cultured
in organ culture dish(Falcon 3037). Retinoic acid was dissolved in 0.1% DMSO and used at concentration 10E-5M. The media were changed every 24hrs, and the palatal shelves were harvested after 24, 48, 72 has after culture. The palatal MEE cells
were
observed with LM & TEM.
@ES The results were as follows :
@EN 1. The palatogenesis of rat in vitro was delayed more or less compared with in vivo.
2. In LM photographs, the palatogenesis was delayed in the retinoic acid-treated group significantly.
3. In TEM photographs, the number of hemidesmosomes and desmosomes were increased in the retinoic acid-treated group. The basal lamina in the retinoic acid-treated group was intact, but not in control group. Cytoplasmic condensations, nuclear
fragmentations, and apoptotic bodies were found in the control group.
According to the above results, it is considered that retinoic acid inhibits programmed cell death and enhances proliferation of cells of the medial edge epithelium of rat palate. However, the exact action mechanism of retinoic acid on programmed
cells
death of MEE cells are still unclear.
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