EN
The immune-like growth factors (IGF-I, IGF-II and IGFBP) play a significant role in human and animal reproduction. It was found that the receptors for these growth factors are present in the uterine endometrium and in the epithelium of the oviduct, and that the gene expression for these receptors depends on the phases of the estrus cycle. The high concentration of IGF-I and IGF-II receptors in the epithelium of the oviduct and in the uterine glands may suggest that the role of these receptors is to regulate the excretory function of the mucous membrane in order to establish an appropriate environment for embryo development. Moreover, IGF-I and IGF-II act mitogenically intensifying the growth of an early embryo. The impact and growing concentration of these factors in embryogenesis depend on the estrogen action. The action of the immune-like factors is multifunctional and not limited only to stimulation of embryo development. The IGF factors also play an important role in the control of apoptosis.