Progesterone and Follicle Stimulating Hormone interact and promote goat preantral follicles survival and development in vitro / Progesterona e Hormônio Folículo-Estimulante interagem e promovem a sobrevivência e o desenvolvimento in vitro de folículos pré-antrais caprinos

We investigated the effects of progesterone and follicle stimulating hormone (FSH) on survival and growth of caprine preantral follicles. Pieces of ovarian tissue were cultured for 1 or 7 days in minimum essential medium (MEM) alone or containing progesterone (1, 2.5, 5, 10 or 20ng/mL), FSH (50ng/mL) or the interaction between progesterone and FSH. Fresh (non-cultured control) and cultured ovarian tissues were processed for histological and ultrastructural studies. After 7 days the addition of FSH to all progesterone concentrations maintained the percentage of normal follicles similar to fresh control. At day 7 of culture, a higher percentage of developing follicles was observed only in 2.5ng/ml of progesterone associated with FSH or 10ng/ml of progesterone alone when compared with control. From day 1 to day 7 of culture, a significant increase in the percentage of developing follicles was observed in MEM and 2.5ng/ml of progesterone + FSH. In addition, after 7 days, in all treatments, there was a significant increase in follicular diameter when compared with control, except for MEM alone and in 5ng/ml of progesterone + FSH or 10ng/ml of progesterone alone. Ultrastructural studies confirmed follicular integrity after 7 days of culture in 2.5ng/ml of progesterone with FSH. In conclusion, this study demonstrated that the interaction between progesterone and FSH maintains ultrastructural integrity, stimulates primordial follicles activation and further growth of cultured caprine preantral follicles.

Este trabalho verificou os efeitos da progesterona e do hormônio folículo-estimulante (FSH) na sobrevivência e no crescimento de folículos pré-antrais caprinos. Fragmentos de tecido ovariano foram cultivados por 1 ou 7 dias em Meio Essencial Mínimo (MEM) sozinho ou contendo progesterona (1, 2.5, 5, 10 ou 20ng/mL), FSH (50ng/mL) ou a combinação entre esses dois hormônios. O tecido fresco (controle não-cultivado) e o cultivado foram processados para análise histológica e ultra-estrutural. Após 7 dias a adição de FSH a todas as concentrações de progesterone manteve o percentual de folículos normais similar ao controle fresco. No dia 7 de cultivo, um alto percentual de folículos em desenvolvimento foi observado somente no tratamento com 2,5ng/ml de progesterona associada ao FSH ou com 10ng/ml de progesterona sozinha, em relação ao controle fresco. Do dia 1 para o dia 7 de cultivo, um aumento significativo no percentual de folículos em desenvolvimento foi observado no MEM sozinho e adicionado de 2,5ng/ml de progesterona + FSH. Além disso, após 7 dias, em todos os tratamentos, houve um aumento significativo no diâmetro folicular em relação ao controle, exceto nos tratamentos com MEM sozinho, 5ng/ml de progesterona + FSH ou 10ng/ml de progesterona sozinha. A análise ultra-estrutural confirmou a integridade follicular após 7 dias de cultivo no tratamento com 2,5ng/ml de progesterona + FSH. Em conclusão, este estudo demonstrou que a interação entre progesterona e FSH mantém a integridade ultra-estrutural, estimula a ativação de folículos primordiais e o posterior crescimento de folículos pré-antrais caprinos cultivados in vitro.

Structure and ultrastructure of spermatozoa and spermiogenesis in three species of Lucilia Robineau-desvoidy, 1830 (Diptera: Calliphoridae).

Morphology of male internal reproductive organs, spermatozoa, and spermiogenesis of the blow-flies Lucilia cuprina, Lucilia eximia, and Lucilia peruviana is first described here, using light and transmission electron microscopy. Spermiogenesis follows the characteristics described for others insect species. The spermatozoa of L. cuprina are similar to those described for other Brachycera. However, in L. eximia and L. peruviana, some differences were found. In L. cuprina and L. eximia species, the spermatozoa are long and thin, measuring about 211 µm and 146 µm in length, of which the head region measures approximately 19 µm and 17 µm, respectively. A polymorphism was observed in L. cuprina and L. eximia spermatozoa. In all three species, the head includes a monolayered acrosome with electron-lucent material. The shape of the nucleus, in cross sections, varies from circular to oval with completely condensed chromatin. Implantation of the axoneme was observed in the middle region of the nucleus, known as the "peg" region. In the next region, the beginning of two mitochondrial derivatives of similar diameter and different lengths in L. cuprina and only one in L. eximia and L. peruviana was observed. In the overlap region, the following structures were observed: nucleus, centriolar adjunct, mitochondrial derivatives, and axoneme. The axoneme is of a conventional insectan type with a 9 + 9 + 2 microtubular arrangement. The male internal reproductive tract consists of testis, deferent ducts, a strongly developed seminal vesicle, accessory glands, and ejaculatory duct. These features are consistent with the structural diversity of the dipteran reproductive tract and spermatozoa, comprising an essential tool for understanding the complex variations found in the Diptera.

Steady-state level of kit ligand mRNA in goat ovaries and the role of kit ligand in preantral follicle survival and growth in vitro.

The aims of this study were to investigate steady-state level of Kit Ligand (KL) mRNA and its effects on in vitro survival and growth of caprine preantral follicles. RT-PCR was used to analyze caprine steady-state level of KL mRNA in primordial, primary, and secondary follicles, and in small (1-3 mm) and large (3-6 mm) antral follicles. Furthermore, ovarian fragments were cultured for 1 or 7 days in Minimal Essential Medium (MEM(+)) supplemented with KL (0, 1, 10, 50, 100, or 200 ng/ml). Noncultured (control) and cultured fragments were processed for histology and transmission electron microscopy (TEM). RT-PCR demonstrated an increase in steady-state level of KL mRNA during the transition from primary to secondary follicles. Small antral follicles had higher steady-state levels of KL mRNA in granulosa and theca cells than large follicles. After 7 days, only 50 ng/ml of KL had maintained the percentage of normal follicles similar to control. After 1 day, all KL concentrations reduced the percentage of primordial follicles and increased the percentage of growing follicles. KL at 10, 50, 100, or 200 ng/ml increased primary follicles, compared to MEM(+) after 7 days. An increase in oocyte and follicular diameter was observed at 50 ng/ml of KL. TEM confirmed ultrastructural integrity of follicles after 7 days at 50 ng/ml of KL. In conclusion, the KL mRNAs were detected in all follicular categories. Furthermore, 50 ng/ml of KL maintained the integrity of caprine preantral follicle cultured for 7 days and stimulated primordial follicle activation and follicle growth.