Effect of ovariectomy on mammary gland expression of TGFalpha and EGFR mRNAs and its relation to mammary gland involution in mice.

摘要

The expression of transforming growth factor alpha (TGFalpha) and epidermal growth factor receptor (EGFR) mRNAs in mammary glands and serum prolactin level were examined in 3-month-old virgin SHN mice 4-108 days after ovariectomy. The formation of normal end-buds and preneoplastic hyperplastic alveolar nodules was significantly reduced by 9 days after ovariectomy (P<0.05). This was associated with decreased levels of serum prolactin. TGFalpha and EGFR mRNA expression in mammary glands declined 18 days after ovariectomy. Thereafter, TGFalpha mRNA tended to increase, while EGFR mRNA continued to decrease.