The Effect of Dexamethasone and Hypervitaminosis A on the Cell Proliferation of Rat Palatal Processes

Abstract

Excess vitamin A and dexamethasone were given to pregnant rats from day 10 to 13 to determine their effect on the proliferation activity ofthe mesenchymal cells ofpalatal/irocesses. 3HTalr was given to the rats on days 14, 15, 16, and 17 of gestation. The animals were killed one hour after injection. Four fetal heads from each rat were prepared for radioautography. The radioautograms were examined microscopically to determine labeling indices for Various areas and regions of the palatal processes. The results show that dexamethasone disturbs the cell proliferation ability of the mesenchymal cells significantly more severely than does vitamin A. The results suggest that, although both teratogenic agents produce an anomaly of similar morphological nature, their effect on cell proliferation ability of the palatal processes varies significantly.