Data/hora: 23/06/2024 17:34:08

Biblioteca(s): | Embrapa Caprinos e Ovinos.
Data corrente: | 07/05/2013
Data da última atualização: | 17/01/2024
Autoria: | MARTINS, F. S.; SARAIVA, M. V. A.; CELESTINO, J. J. H.; BRUNO, J. B.; ALMEIDA, A. P.; CUNHA, R. M. S.; SILVA, J. R. V.; CAMPELO, C. C.; LUCCI, C. M.; MATOS, M. H. T.; FIGUEIREDO, J. R.
Título: | Expression of protein and mRNA encoding Insulin Growth Factor-I (IGF-I) in goat ovarian follicles and the influence of IGF-I on in vitro development and survival of caprine preantral follicles.
Ano de publicação: | 2010
Fonte/Imprenta: | Animal Reproduction, v. 7, n. 4, p. 349-361, Oct./Dec. 2010.
Idioma: | Inglês
Conteúdo: | Abstract: The aim of this study was to investigate the protein and mRNA expression levels of IGF-I and the effects of IGF-I on preantral follicle survival and development, using an in vitro goat ovarian cortical culture system. The ovaries were used for immunohistochemical localization of IGF-I protein or used to demonstrate mRNA expression of IGF-I. For the latter goal, preantral and antral follicles, cumulus-oocyte complex, mural granulosa and theca cells were collected to study mRNA expression. For in vitro studies, ovarian cortex were cultured for 1 and 7 days with MEM supplemented IGF-I (0, 1, 10, 50, 100 or 200 ng/ml). Immunohistochemical results showed strong reactions for IGF-I in oocytes and granulosa cells of all follicular stages, except in granulosa cells of primordial and primary follicles. mRNA expression analysis demonstrated a discrete increase in the production of IGF-I during the transition from primordial to the primary and secondary follicle stages. After 7 days of culture, addition of 50 ng/ml of IGF-I to the medium showed the greatest percentage of normal follicles when compared with other concentrations. Furthermore, the highest percentage of primary follicles was observed after 7 days of culture in MEM+plus 10 and 50 ng/ml of IGF-I. Culture of ovarian tissue for 7 days in MEM+plus 50 ng/ml of IGF-I promoted the greatest increase (P < 0.05) in follicular diameter of all of the concentrations tested. In conclusion, IGF-I protein and mRNA were expressed in all follicular categories of goat. Furthermore, IGF-I maintained preantral follicle survival, promoted primordial follicle activation and stimulated the transition from intermediate to primary follicles.
Palavras-Chave: | Folículo pré-antral; IGF-I.
Thesagro: | Cabra; Caprino; Endocrinologia; Fator de crescimento; Hormônio; Insulina; Ovário; Reprodução animal.
Categoria do assunto: | --
Registro original: | Embrapa Caprinos e Ovinos (CNPC)
Exemplares: | CNPC - (27187-1) - ADD - AP - DD -  -  -  - DIS