- Vitamin A is involved in estrogen-induced cell proliferation but not in cytodifferentiation of the chicken oviduct. Ninomiya, Y., Arao, Y., Kometani, T., Hiwatashi, S., Yamasaki, T., Erikawa, T., Yamaguchi, H., Hasegawa, T., Masushige, S., Kato, S. J. Endocrinol. (1996)