The Stability of Vitamin A-induced Metaplasia of Mouse Vibrissa Follicles In Vitro

The study tested the stability of glandular morphogenesis and mucous metaplasia in embryonic mouse vibrissa follicles induced by excess vitamin A in vitro. Observations showed that 13.5-day embryonic upper lip skin formed branching glands secreting mucus after 10-14 days in a medium with 4.7 microgram/ml retinol. Even when switched to standard medium after 7 days, glandular changes persisted, though some hair follicles reverted to their original state. Similar persistence was noted in 13-day embryos treated with 6.0 microgram/ml vitamin A for 3 days. The addition of high-dose cortisol did not alter the moderate glandular morphogenesis in 15-day skin. The study suggested that glandular morphogenesis initiation in mouse follicles by vitamin A is akin to a new secondary embryonic induction rather than epithelial modulation.