Differential hormonal response of epidermal growth factor concentration in the developing mouse: synergism of triiodothyronine and dexamethasone in epidermal maturation.

The hormonal regulation of epidermal growth factor concentration in neonatal mouse skin and submandibular gland is examined by radioimmunoassay. The results show triiodothyronine but not dexamethasone effects an unequivocal elevation in skin EGF content. In contrast, the neonatal submandibular gland is hormonally unresponsive during this period. Combined therapy with T3 and dexamethasone produces precocious incisor eruption compared to the effect of either hormone alone. The mechanism of this synergistic acceleration of an EGF-related developmental event is unknown.