Effects of dexamethasone on phospholipase activities in palate mesenchyme cells in vitro.

Treatment of primary cultures of palate mesenchyme cells from AJAX strain embryos with dexamethasone inhibited only phospholipase activity expressed at pH 7.5. A similar treatment did not have such an effect on palate mesenchyme cells from C57BL/6J strain embryos. Since the AJAX strain embryo is sensitive to the induction of cleft palate by exogenous glucocorticoids and the C57BL/6J strain is less so, these data allow consideration of phospholipase activity as a site of regulation for development of the palate.