Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology

Oestrogen regulation of insulin-like growth factor binding protein-3 (IGFBP-3) and expression of IGFBP-3 messenger RNA in the ovine endometrium

A. J. Peterson, A. M. Ledgard and S. C. Hodgkinson

Reproduction, Fertility and Development 10(3) 241 - 248
Published: 1998


Transcriptional regulation of insulin-like growth factor binding protein-3 (IGFBP-3) by oestrogen was investigated by Northern blot hybridization of endometrial tissue mRNA from anoestrous ewes treated with oestradiol-17β at either 0, 40 or 80 µg per day for 7 days. The 2.6 kb IGFBP-3 transcript, seen in control animals, was virtually undetectable in treated animals. This suppressive effect was reflected in Western ligand blots of the uterine luminal fluid (ULF) proteins where the concentration of IGFBP-3 was significantly decreased with increasing oestrogen treatments. IGFBP-2 levels were increased with oestradiol treatment but no significant effect was seen on the other minor IGFBP’s present in the ULF. Northern analysis also showed that the IGFBP-3 transcript was present from days 12 to 16 of the oestrous cycle but was either absent or very weak on days 0 (oestrus) and 9 of cycling ewes. In situ hybridization of endometrial tissue sections localized the IGFBP-3 mRNA to the luminal epithelial cell layer, areas of the stromal tissue and in some glandular epithelial cells. Oestradiol treatment of ewes down-regulated expression of IGFBP-3 in the endometrium; therefore, the low levels of IGFBP-3 in ULF during the early part of the oestrous cycle is possibly due to elevated levels of plasma oestradiol around oestrus.

© CSIRO 1998

Rent Article (via Deepdyve) Export Citation Cited By (9)