Influence of scrotal bipartition on spermatogenesis yield and sertoli cell efficiency in sheep / Influência da bipartição escrotal sobre o rendimento da espermatogênese e eficiência das células de Sertoli em ovinos

With the objective to assess the effect of scrotal bipartition on spermatogenesis in sheep, the testes were used from 12 crossbred rams of sheep farms in the municipality of Patos, Paraíba, Brazil, distributed into two groups: GI with six rams with scrotal bipartition, and GII with six rams without scrotal bipartition. The testicular biometry was measured and the testes were collected, fixed in Bouin and fragments were processed to obtain histological slides. The spermatogenesis yield and the Sertoli cell efficiency was estimated by counting the cells of the spermatogenetic line at stage one of the seminiferous epithelium cycle and the Sertoli cells. The results were submitted to analysis of variance with the ASSISTAT v.7.6 program and the mean values were compared by the Student-Newman-Keuls test (SNK) at 5% significance. The testicular biometric parameters did not show statistical difference (p>0.05) between the groups. The meiotic, spermatogenetic and Sertoli cell efficiency were higher in bipartitioned rams (p<0.05), while the mitotic yield did not differ (p>0.05) between GI and GII. The results indicated that there is superiority in the spermatogenetic parameters of bi-partitioned rams, suggesting that these sheep present, as reported in goats, indication of better reproductive indices.

Com o objetivo de avaliar o efeito da bipartição escrotal sobre a espermatogênese em ovinos, foram utilizados os testículos de 12 ovinos sem raça definida oriundos de criadouros do município de Patos-PB, Brasil, distribuídos em dois grupos, GI de seis animais com bipartição escrotal e o GII de seis animais sem bipartição escrotal. Realizou-se a aferição da biometria testicular, em seguida, os testículos foram coletados, fixados em Bouin e fragmentos foram processados para obtenção de lâminas histológicas. Foi estimado o rendimento da espermatogênese e eficiência das células de Sertoli contando-se as células da linhagem espermatogênica no estádio I do Ciclo do Epitélio Seminífero, bem como as células de Sertoli. Os resultados foram submetidos à análise de variância pelo programa ASSISTAT v.7.6 e os valores médios foram comparados pelo teste Student-Newman-Keuls (SNK) a 5% de significância. Os parâmetros de biometria testicular não apresentaram diferença estatística (p>0,05) entre os grupos. Os rendimentos meiótico, espermatogênico e a eficiência das células de Sertoli mostraram-se superiores em animais bipartidos (p<0,05), enquanto o rendimento mitótico não diferiu (p>0,05) entre GI e GII. Os resultados indicaram existir superioridade nos parâmetros espermatogênicos de ovinos bipartidos, sugerindo que estes animais apresentam, assim como constatado em caprinos, indicativo de melhores índices reprodutivos.

New perspectives in the diagnosis of pediatric male hypogonadism: the importance of AMH as a Sertoli cell marker / Novas perspectivas no diagnóstico do hipogonadismo pediátrico masculino: a importância do AMH como marcador de células de Sertoli

Sertoli cells are the most active cell population in the testis during infancy and childhood. In these periods of life, hypogonadism can only be evidenced without stimulation tests, if Sertoli cell function is assessed. AMH is a useful marker of prepubertal Sertoli cell activity and number. Serum AMH is high from fetal life until mid-puberty. Testicular AMH production increases in response to FSH and is potently inhibited by androgens. Serum AMH is undetectable in anorchidic patients. In primary or central hypogonadism affecting the whole gonad and established in fetal life or childhood, serum AMH is low. Conversely, when hypogonadism affects only Leydig cells (e.g. LHβ mutations, LH/CG receptor or steroidogenic enzyme defects), serum AMH is normal or high. In pubertal males with central hypogonadism, AMH is low for Tanner stage (reflecting lack of FSH stimulus), but high for the age (indicating lack of testosterone inhibitory effect). Treatment with FSH provokes an increase in serum AMH, whereas hCG administration increases testosterone levels, which downregulate AMH. In conclusion, assessment of serum AMH is helpful to evaluate gonadal function, without the need for stimulation tests, and guides etiological diagnosis of pediatric male hypogonadism. Furthermore, serum AMH is an excellent marker of FSH and androgen action on the testis.

As células de Sertoli são a população de células mais ativa nos testículos durante a primeira e segunda infância. Neste período, o hipogonadismo só pode ser evidenciado sem o uso de testes estimulatórios se a função das células de Sertoli for avaliada. O AMH é um marcador útil do número e da atividade das células de Sertoli no período pré-puberal. A concentração sérica de AMH é alta da metade da vida fetal até a metade da puberdade. A produção de AMH pelos testículos aumenta em resposta ao FSH e é potencialmente inibida por androgênios. O AMH sérico não é detectável em pacientes anorquídicos. No hipogonadismo central ou primário afetando a gônada inteira, ou estabelecido na vida fetal ou infância, a concentração de AMH sérica é baixa. Por outro lado, quando o hipogonadismo afeta apenas as células de Leydig (por exemplo, nas mutações, LHβ, defeitos do receptor de LH/CG ou das enzimas esteroidogênicas), a concentração de AMH sérico é normal ou alta. Em meninos púberes com hipogonadismo central, a concentração de AMH é baixa para o estágio na escala de Tanner (refletindo a falta de estímulo pelo FSH), mas alta para a idade (indicando a falta do efeito inibidor da testosterona). O tratamento com FSH provoca um aumento do AMH sérico, enquanto a administração de hCG aumenta os níveis de testosterona, que fazem a downregulation do AMH. Em conclusão, a concentração sérica de AMH é útil na avaliação da função gonadal, excluindo a necessidade de testes estimulatórios, e direciona o diagnóstico etiológico do hipogonadismo pediátrico masculino. Além disso, o AMH sérico é um marcador excelente da ação do FSH e dos androgênios nos testículos.

Sperm ultrastructure and spermatogenesis in the lizard, Tropidurus itambere

Spermatogenesis, with emphasis on spermiogenesis, is described for the lizard, Tropidurus itambere, using light microscopy, phase contrast and epifluorescence, as well as scanning and transmission electron microscopy. Cellular differentiation involves events of chromatin condensation, nuclear elongation and the formation of structural complexes, such as the acrosomal and axonemal ones. Other new characteristics, exclusive for this species, include various aspects of the subacrosomal granule, the insertion of the pro-acrosomal vesicle and the development of these structures to participate in the acrosomal complex. Radial projections occurjust above the nuclear shoulders, which have been recognized already from the beginning of cellular elongation. The development of the midpiece, the dense bodies, formation of the flagellum and elimination of residual cytoplasm result in the final characterization of the mature spermatozoon. Comparisons between Tropiduridae and other lizard families are made.

Hormônio anti-mülleriano: revisäo e contribuiçäo para a investigaçäo das ambigüidades genitais / Antimullerian hormone: review and contribution for the investigations of genital ambiguities

A investigaçäo etiológica das ambigüidades genitais com cariótipo 46,XY apresenta dificuldades freqüentes. A funçäo testicular tem sido tradicionalmente avaliada pela capacidade esteroidogênica das célulacs de Leydig e pela espermatogênese. Recentemente, demonstrou-se qua a avaliaçäo sérica do hormônio anti-mülleriano (HAM)como marcador da funçäo das célilas de Sertoli pode ser de grande valia nesta investigaçäo. O objetivo desta revisäo é apresentar aspectos históricos e fisiológicos do HAM, e sua utilidade na investigaçäo diagnóstica de pacientes com intersexo. Também é mostrada a experiência dos autores na avaliaçäo de intersexo com dosagens combinadas de andrógenos, HAM e testosterona.

Biomatrix effect on Sertoli cells phospholipids

In order to investigate the influence of biomatrix on Sertoli cell morphology and on the phospholipids content, these cells were isolated from tests of 15-day old Wistar rats and plated ontoplastic coated with extracellular matrix extracted froma seminiferous tubules, here denoted biomatix. When the Sertoli cells were cultured on biomatrix they did not from a monolayer until day 7 of culture, while cells plated onto plastic did so 48 h after plating. On day 5 of culture. Sertoli cells were incubated for 48 h with 5 µCi/ml 32P. There was no difference in 32P incorporation into lipids of cells plated onto biomatrix or plastic. However, there was a larger amount of phospholipid phosphate in cells plated onto biomatrix than onto plastic. When the phospholipds were analyzed by bidimensional thin-layer chromatography, no diferences were detected in their distribution; however, there was a significant decrease in the percentage of sphingomyelin in cells plated onto biomatrix when compared to plastic. These results showed that the cells cultured on biomatrix change their phospholipids content, but not their distribution. The importance of a small reduction in sphingomyelin content remains to be investigated

Distribution of action filaments in spermatogenic cells and sertoli cells of mouse: an ultrastructural study

Study of the distribution of actin in spermatogenic cells and Sertoli cells of mouse might be important in elucidating how they may contribute to some of the processes that occur during spermatogenesis. Fifteen adult healthy male mice were used for this study. Testicular specimens were taken, fixed and processed for examination by a transmission electron microscope. Actin filaments were demonstrated in specific regions of the seminiferous epithelium. In spermatogenic cells, they occurred in the intercellular bridges between spermatogenic cells, in the subacrosomal spaces, and in the gap between the capitulum and the implantation fossa of differentiating spermatids. In Sertoli cells, they were abundant in ectoplasmic specialization and around the bulbar segment of tubulobulbar processes of late spermatids. At all of these sites, the filaments were related to the plasma membrane. The possible functional significance of actin filaments in such location was discussed

Fisiologia da célula de Sertoli / Physiology of Sertoli cell

Apresenta-se uma monografia didática sobre a fisiologia da célula de Sertoli.