The effects of IGF-I on bovine follicle development and IGFBP-2 expression are dose and stage dependent
| Autor: | D. G. Armstrong, Evelyn E. Telfer, John P Binnie, Bruce K. Campbell, Kirsty A Walters |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Embryology
medicine.medical_specialty Somatic cell medicine.medical_treatment Stimulation Tissue Culture Techniques Follicle Oogenesis Endocrinology Ovarian Follicle Internal medicine Follicular phase Image Processing Computer-Assisted medicine Animals Humans RNA Messenger Insulin-Like Growth Factor I Antrum In Situ Hybridization Granulosa Cells Dose-Response Relationship Drug Estradiol Chemistry Growth factor Obstetrics and Gynecology Cell Biology Oocyte Antral follicle Immunohistochemistry Recombinant Proteins Stimulation Chemical Insulin-Like Growth Factor Binding Protein 2 medicine.anatomical_structure Reproductive Medicine Oocytes Cattle Female |
| Zdroj: | Reproduction. 131:515-523 |
| ISSN: | 1741-7899 1470-1626 |
| DOI: | 10.1530/rep.1.00682 |
| Popis: | This study aimed to determine the effect of insulin-like growth factor-I (IGF-I) on early antral bovine follicular development, and the expression of insulin-like growth factor-binding protein-2 (IGFBP-2). Antral follicles separated into three different size groups were cultured for 6 days in medium supplemented with either a low (10 ng/ml) or high (1 μg/ml) dose of human recombinant IGF-I. Oestradiol production by follicles in all size ranges, cultured in the presence of the high concentration of IGF-I, significantly increased by day 6 (P < 0.05). Follicles in the smallest size range, 165–215 μm, cultured in a high dose of IGF-I, were found to be significantly increased in size (P < 0.01). Oocyte health of the largest follicles (281–380 μm) was significantly improved by the addition of IGF-I to the culture medium. mRNA expression of IGFBP-2 was decreased in the granulosa cells of follicles, size range 216–280 μm, cultured with a high dose of IGF-I (P < 0.05). Granulosa cells (P < 0.05) and oocytes (P < 0.01) of the largest follicles (281–380 μm) showed a decrease in IGFBP-2 expression (protein) when cultured in the control and low-IGF-I treatment groups. Therefore, the response of a bovine follicle to IGF-I is both dose and stage dependent. This work supports a role for IGF-I in modulating somatic and germ-cell maturation and development in early antral follicles. Furthermore, the inverse relationship between the level of IGF-I stimulation and IGFBP-2 expression suggests a local regulatory system modulating IGF-I availability. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|