Symposium: growth hormone and insulin-like growth factors role of the insulin-like growth factors and their binding proteins in lactation

摘要

Insulin-like growth factor(IGF)-I is though to mediate a portion of the effects of bST on lactation in dairy cows. Serum concentrations of IGF-I are in- creased in lactation cows that were treated with bST, and IGF-I receptors are present in bovine mammary tissue. In addition, close arterial infusion of IGF-I into the mammary gland of goats increases milk yield. Little evidence exists to support a direct galac- topoietic effect of IGF-I in ruminants. However, IGF-I is a potent mitogen for mammary epithelia cell and may also influence the inhibition of apoptosis of this cell type.