Binding of insulin-like growth factor-I to rat uterus; variations during sensitization and decidualization

in European Journal of Endocrinology
Restricted access


IGF-I receptors have been identified and characterized in a variety of tissues. In this study receptors for IGF-I in the rat uterine tissue were identified and characterized. We have demonstrated IGF-I receptors in crude uterine membranes by binding and cross-linking experiments. IGF-I binding to the rat uterine membranes displayed time, temperature and pH dependance, and optimal binding conditions were achieved by 20 h of incubation at 4°C, at a pH of 7.8. Uterine IGF-I binding sites were specific for binding IGF-I peptide and demonstrated less than 100 × lower affinity for insulin. The binding was reversible and Scatchard analysis indicated presence of a single class of binding sites with an apparent dissociation constant of 1.68 ± 0.24 nmol/l and Bmax of 0.82 ± 0.1 pmol/mg protein. During estrogen treatment, sensitization and decidualization there was an overall increase of membrane proteins in the uterus and a relative decrease of IGF-I receptors per unit of protein. When expressed on a per uterus basis, there was a progressive increment in total IGF-I binding in estradiol-treated, sensitized, and decidualized uterus compared with controls. These data indicate a possible role for IGF-I in uterine cell multiplication and further differentiation to decidual cells in response to deciduogenic stimuli.


     European Society of Endocrinology

Related Articles

Article Information


All Time Past Year Past 30 Days
Abstract Views 69 69 0
Full Text Views 47 16 0
PDF Downloads 61 30 0


Cited By


Google Scholar