Steady-state levels of vasoactive intestinal peptide (VIP) mRNA in goat ovaries and the effect of VIP on the in vitro development of isolated preantral follicles

The aims of this study were to verify the steady-state level of vasoactive intestinal peptide (VIP) mRNA in goat follicles at various developmental stages and to investigate the influence of VIP on the survival, antrum formation and growth of secondary follicles cultured for 6 days. Primordial, primary and secondary goat follicles and small and large antral follicles were obtained to quantify VIP mRNA by real-time reverse transcription with the polymerase chain reaction. The influence of VIP and the presence or absence of follicle-stimulating hormone (FSH) on the development of secondary follicles and on mRNA expression for VIP and FSH receptor (FSHR) were determined after 6 days of culture. Survival, antrum formation and follicular diameter were evaluated every other day of culture. The levels of VIP mRNA in primary and secondary follicles were significantly higher than in primordial follicles. Cumulus–oocyte complexes (COCs) from both small and large antral follicles had significantly higher levels ofVIP mRNA than their respective granulosa/theca cells. During culture, the addition of VIP and/or FSH had o effect on follicular development. However, the presence of FSH and/or VIP in the culture medium significantly reduced VIP mRNA levels, but did not alter FSHR mRNA levels. In conclusion, VIP mRNA was detected in all goat follicular categories and cellular types, VIP and/or FSH did not affect the development of secondary follicles and reduce the expression of VIP mRNA levels.(AU)

Steady-state levels of vasoactive intestinal peptide (VIP) mRNA in goat ovaries and the effect of VIP on the in vitro development of isolated preantral follicles

The aims of this study were to verify the steady-state level of vasoactive intestinal peptide (VIP) mRNA in goat follicles at various developmental stages and to investigate the influence of VIP on the survival, antrum formation and growth of secondary follicles cultured for 6 days. Primordial, primary and secondary goat follicles and small and large antral follicles were obtained to quantify VIP mRNA by real-time reverse transcription with the polymerase chain reaction. The influence of VIP and the presence or absence of follicle-stimulating hormone (FSH) on the development of secondary follicles and on mRNA expression for VIP and FSH receptor (FSHR) were determined after 6 days of culture. Survival, antrum formation and follicular diameter were evaluated every other day of culture. The levels of VIP mRNA in primary and secondary follicles were significantly higher than in primordial follicles. Cumulus–oocyte complexes (COCs) from both small and large antral follicles had significantly higher levels ofVIP mRNA than their respective granulosa/theca cells. During culture, the addition of VIP and/or FSH had o effect on follicular development. However, the presence of FSH and/or VIP in the culture medium significantly reduced VIP mRNA levels, but did not alter FSHR mRNA levels. In conclusion, VIP mRNA was detected in all goat follicular categories and cellular types, VIP and/or FSH did not affect the development of secondary follicles and reduce the expression of VIP mRNA levels.

A superfamília dos fatores de crescimento transformante-β e o controle da foliculogênese em mamíferos / Transforming growth factors -β superfamily members and control of folliculogenesis in mammals

A foliculogênese ovariana é um processo complexo caracterizado pela formação, crescimento e maturação folicular. Esta revisão discute a localização, os sítios de ação e as funções de fatores da família TGF-β [proteínas morfogenéticas ósseas dos tipos 2 (BMP-2), 4 (BMP-4), 6 (BMP-6), 7 (BMP-7), 15 (BMP-15), fator de diferenciação do crescimento-9 (GDF-9), ativina-A, inibina, hormônio anti-Mülleriano (AMH) e fator de crescimento transformante-ß (TGF-ß)] na regulação da foliculogênese em mamíferos. Alguns fatores, como o AMH, atuam inibindo o crscimento dos folículos primordiais e reduzindo a sensibilidadade dos folículos em crescimento ao FSH, enquanto vários outros (BMP-2, 4, 7, 15, GDF-9, ativina-A e TGF-ß) estimulam o crecimento folicular. Em geral, a foliculogênese é regulada por uma complexa interação desses fatores de crescimento com as gonadotrofinas.(AU)

Ovarian folliculogenesis is a complex process that includes follicular formation, growth and maturation. This review discuss the localization and functions of TGF-β family members [bone morphogenetic proteins 2 (BMP-2), 4 (BMP-4), 6 (BMP-6), 7 (BMP-7), 15 (BMP-15), growth and differentiation factor-9 (GDF-9), activin-A, inibin, anti-Müllerian hormony (AMH) and transforming growth factor-ß (TGF-ß)] in the regulation of ovarian folliculogenesis in mammals. Some of these factors, such as AMH, inhibit growth of primoridal follicles and reduce sensitity of growing follicles to FSH, while various others (BMP-2, 4, 7, 15, GDF-9, activina-A and TGF-ß) stimulate follicular growth. In general, folliculogenesis is regulated by a complex interaction of these factors with gonadotrophins.(AU)

A superfamília dos fatores de crescimento transformante-β e o controle da foliculogênese em mamíferos / Transforming growth factors -β superfamily members and control of folliculogenesis in mammals

A foliculogênese ovariana é um processo complexo caracterizado pela formação, crescimento e maturação folicular. Esta revisão discute a localização, os sítios de ação e as funções de fatores da família TGF-β [proteínas morfogenéticas ósseas dos tipos 2 (BMP-2), 4 (BMP-4), 6 (BMP-6), 7 (BMP-7), 15 (BMP-15), fator de diferenciação do crescimento-9 (GDF-9), ativina-A, inibina, hormônio anti-Mülleriano (AMH) e fator de crescimento transformante-ß (TGF-ß)] na regulação da foliculogênese em mamíferos. Alguns fatores, como o AMH, atuam inibindo o crscimento dos folículos primordiais e reduzindo a sensibilidadade dos folículos em crescimento ao FSH, enquanto vários outros (BMP-2, 4, 7, 15, GDF-9, ativina-A e TGF-ß) estimulam o crecimento folicular. Em geral, a foliculogênese é regulada por uma complexa interação desses fatores de crescimento com as gonadotrofinas.

Ovarian folliculogenesis is a complex process that includes follicular formation, growth and maturation. This review discuss the localization and functions of TGF-β family members [bone morphogenetic proteins 2 (BMP-2), 4 (BMP-4), 6 (BMP-6), 7 (BMP-7), 15 (BMP-15), growth and differentiation factor-9 (GDF-9), activin-A, inibin, anti-Müllerian hormony (AMH) and transforming growth factor-ß (TGF-ß)] in the regulation of ovarian folliculogenesis in mammals. Some of these factors, such as AMH, inhibit growth of primoridal follicles and reduce sensitity of growing follicles to FSH, while various others (BMP-2, 4, 7, 15, GDF-9, activina-A and TGF-ß) stimulate follicular growth. In general, folliculogenesis is regulated by a complex interaction of these factors with gonadotrophins.