Estrogen Induces Insulin—Like Growth Factor—I Expression in the Rat Uterus
Autor: | Liam J. Murphy, Leigh C. Murphy, Henry G. Friesen |
---|---|
Rok vydání: | 1987 |
Předmět: |
medicine.medical_specialty
medicine.drug_class Ovariectomy medicine.medical_treatment Radioimmunoassay Uterus Biology Insulin-like growth factor Paracrine signalling Endocrinology Internal medicine medicine Animals Insulin-Like Growth Factor I Autocrine signalling Molecular Biology Hypophysectomy Estradiol Growth factor Ovary Nucleic Acid Hybridization Rats Inbred Strains General Medicine Somatomedin Rats medicine.anatomical_structure Estrogen Growth Hormone Pituitary Gland Ovariectomized rat RNA Female |
Zdroj: | Molecular Endocrinology. 1:445-450 |
ISSN: | 1944-9917 0888-8809 |
Popis: | The inability to convincingly demonstrate a mitogenic effect of estrogen on isolated uterine cells in culture suggests that autocrine or paracrine growth factors may be important in the estrogen-induced uterine proliferative response. Here we report that uterine expression of insulin-like growth factor-I (IGF-I), an important mediator of GH action, is increased after 17 beta-estradiol (5 micrograms/100 g bw, ip) administration to ovariectomized prepubertal rats. An increase in uterine IGF-I mRNA abundance, approximately 14-fold above untreated controls, was apparent 6 h after estrogen administration and the level achieved exceeded that seen in the uterus from intact mature rats during diestrus. In contrast to the increase in IGF-I expression in the uterus, no significant change in serum IGF-I concentration or hepatic or renal IGF-I mRNA abundance was demonstrable after 17 beta-estradiol injection of ovariectomized prepubertal rats. The increase in uterine IGF-I expression, was similar in both pituitary-intact and hypophysectomized, ovariectomized rats. We believe this is the first report of induction of IGF-I expression by estrogen in vivo. As such, the finding expands the role and significance of IGF-I as a mediator of growth beyond that related to GH. |
Databáze: | OpenAIRE |
Externí odkaz: |