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.

Morphological study of the spermatogenesis in the teleost Piaractus mesopotamicus

The spermatogenesis of Piaractus mesopotamicus was investigated under light and transmission electron microscopy. The specimens were captured from their natural environment (Rio Miranda and Rio Aquidauana, Pantanal Matogrossense, Brazil) during April and September. The results were compared with the spermatogenic data of specimens under captivity condition. In both conditions, P. mesopotamicus presented the typical spermatogenesis pattern of the teleost fishes, showing no significative differences. The spermatozoon was classified as type I, which has a globular head without acrosome, a short middle piece and a long tail constituted only by the flagellum. This type of spermatozoon is considered the basic type in fishes.

Variaciones del funcionamiento testicular en Octopus mimus adultos / Testicular function variations in adult Octopus mimus

Octopus mimus macho madura precozmente. En general, sobre 200 g son maduros y permanecen en dicha condición hasta la muerte. En consideración a que no hay antecedentes de la fisiología testicular de los machos adultos, fueron estudiadas la función gamética mediante análisis histológico de los túbulos seminíferos y la función endocrina, cuantificando en el testículo, progesterona y testosterona, en conjunto con el crecimiento y funcionalidad de los órganos blancos del andrógeno. Se detectaron tres categorías de machos adultos: maduros jóvenes, de madurez máxima y en regresión. Los animales en regresión producen menor cantidad de ambas hormonas y muestran regresión de la función espermatogénica. La declinación de ambas funciones del testículo indica el estado de envejecimiento de Octopus mimus. Por el contrario, los que están en máxima madurez tienen la mayor capacidad espermatogénica y androgénica, en conjunto con el mejor funcionamiento de las glándulas reproductivas anexas, cualidades que podrían ser consideradas en las normativas de manejo y futuras actividades de cultivo de la especie.

electron microscpic study of the effect of phyo-oestrogens on the seminiferous tubules of young adult male albino rats

Phyto-oestrogens are a group of biologically active plant-based compounds, they are present in the edible plants, Phyto-oestrogens are found in many foods including: wheat rice, oats, barley, carrots, potatoes, apples, parsley and soya beans. The present study was carried out to study the ultra-structural possible changes that might occur in the seminiferous tubules of young adult male albino rats after the continuous consumption of a diet rich in soya beans [a rich source of Phyto-oestrogens]. Twenty young adult male albino rats were used. They were divided into two main groups: A control group, and a second group further subdivided into two subgroups: the first subgroup was provided with grinded soya beans as half of its total amount of consumed food for one month, the second subgroup [withdrawal group] had the same regimen as the first subgroup, then fed standard diet for another month. Results revealed that seminiferous tubules of the first subgroup showed variable degrees of degeneration from mild to severe in all types of cells, the sertoli and the spermatogenic cells. The mildly affected sertoli cells showed mitochondrial affection and large sized lipid droplets. The severely affected cells showed pyknotic irregular nuclei and many cytoplasmic vacuoles of different sizes and shapes. The mildly affected spermatogenic cells exhibited mitochondrial alternation and nuclear and cellular membranes affection. The severely affected cells showed, small sized irregular nuclei, multiple autophagic vacuoles, lysed cytoplasm and malformed spermatozoa. Seminiferous tubules of the withdrawal group showed persistence of the degenerative changes occurring in all the cells in a more profound way. Mitochondrial affection was still manifest, the sertoli cells .showed also many secondary lysosomes. The spermatogenic cells showed wide intra and intercellular spaces and many vacuolated cells. The spermatozoa depicted frequent degrees of abnormalities and malformations. The present study showed that Phyto-oestrogens provided regularly to young adult male rats can cause degenerative cellular changes affecting spermato and spermiogenesis

Aspectos imunológicos da torçäo testicular: trabalho experimental em ratos / Immunologic aspects of testicular torsion: experimental study in wistar rats

As atividades testiculares, hormonal e espermiogênica säo de extrema importância para o homem e para a manutençäo e o aprimoramento da humanidade. Trauma, tumores, varicocle, criptorquidia, anorquia, atrofias, torçäo de cordäo espermático, estäo entre as diversas causas da infertilidade masculina. A integridade da barreira testículo - sangüínea parece ter um papel fundamental na patôgenese da orquite auto-imune. A orquite auto-imune é um processo inflamatório testicular mediado por formaçäo de anticorpos, contra os próprios antígenos testiculares do indivíduo, causando lesöes no epitélio germinativo. Neste estudo foram utilizados oitenta (80) ratos Wistar, singênicos, machos, adultos, separados em dez grupos, submetidos à torçäo unilateral do testículo, sob anestesia, por um período de duas à doze horas, seguido, entäo, de destorçäo e exame anatomopatológico das gônadas contralateral e ipsilateral, em períodos que variaram de duas à dez semanas. Estes testículos foram analisados através das técnicas de histologia e de imunofluorescência com a utilizaçäo de anticorpos monoclonais para as imunoglobulinas IgA, IgG e IgM de coelho e cabra, contra os antígenos testiculares do rato, para que se estudasse as possíveis alteraçöes no tecido testicular do animal, objetivando a comprovaçäo da existência de complexos auto-imunes no epitélio germinal. O estudo demonstrou a presença de imunoglobulinas, principalmente das classes IgG e IgM na luza e no interstício dos túbulos semíferos. Alteraçöes estruturais do testículo contralateral, näo torcido, foram demonstradas. Os resultados deste experimento indicam que o sistema inume de animais sadios contém linfócitos com receptores para os próprios antígenos, capazes de, na torçäo unilateral do cordäo espermático, promoverem uma doença auto-imune. A utilizaçäo de substâncias imuno-supressoras, neste estudo, o corticóide, foi feita para tentar minimizar ou mesmo coibir o processo auto-agressivo. Existiu uma proteçäo testicular contralateral efetiva, com o uso precoce da referida droga. É sugerido que a permanência de um testículo necrótico na bolsa escrotal, após torçäo prolongada, pode levar à subfertilidade ou infertilidade.

Ultra-estrutura do tecido circundante da rede extratesticular e dos dúctulos eferentes no gato (Felis domestica, L.) / Ultrastructure of the boundary tissue of the extratesticular rete and efferent ductules in the cat (Felis domestica, L.)

No gato o tecido circundante ou lâmina própria da rede extratesticular e dos dúctus eferentes é formado por colágeno com disposiçäo lamelar e fibrilar e por células contráteis alongadas. Essas células säo representadas principalmente por fibras musculares lisas e miofibroblastos

Stereological and ultrastructural study of seminiferous tubules in normal testes and in patients with varicocele

Testicular biopsies from fertile men and patients with varicocele were evaluated and examined by using the recent stereological technique and electron microscope. This study quantitated the seminiferous epithelium using the stereological methods. The numerical density of the germ cells was generally reduced in patients with varicocele when compared with that in the normal fertile men. However such reduction was not associated with a similar change in the supporting Sertoli cells. Moreover, the different ratios between various germ cells and Sertoli cells were statistically reduced in varicocele group. The seminiferous tubules were examined by light and electron microscope. The tissue architecture of the tubules in varicocele patients ranged from mild to severely altered. In affected tubules, spermatid nuclear and acrosomal morpology was abnormal. Sloughing of the individual germ cells as well as the vacuolization and degeneration of the Sertoli cell cytoplasm were evindent. Furthermore, Sertoli-spermatid junctional complexes appeared to be structurally abnormal, whereas Sertoli-Sertoli junctional cornplexes appeared to be structurally intact. On the basis of the results in this work, the Sertoli cell is, in fact, the primary intratubular site of alteration in varicocele patients leading secondarily to sloughing and spermatogenic disruption

Orquitis autoinmune experimental / Experimental autoimmune orchitis

A pesar de los numerosos trabajos realizados en el modelo de orquitis autoinmune experimental (OAE) aún existen varias incógnitas acerca de su patogenia. Clásicamente, la OAE se indujo en cobayos utilizando como antígenos, espermatozoides u homogenado testicular. Nuestro primer interés fue determinar si antígenos no espermáticos como los componentes extracelulares de la pared del túbulo seminífero, utilizados como inmunógenos, eran capaces de inducir un cuadro autoinmune testicular. Obtuvimos, a partir del testículo de la rataÑ a) una preparación rica en membranas basales del túbulos seminífero (STBM) y b) a partir del STBM, una fracción no relacionada al componente colágeno (D-STBM) que demostró poseer determinantes antigénicos comunes con la laminina, principal glicoproteína no colágena de las membranas basales. El 50% de las ratas inmunizadas con STBM, D-STBM o laminina, desarrolaron una lesión testicular moderada, multifocal, caracterizada por leves infiltrados intersticiales, alteraciones de las membranas basales del túbulo seminífero y de la célula de Sertoli, descamación del epitelio germinal y atrofia tubular. También se detectaron anticuerpos circulantes y una respuesta de inmunidad celular específica. A su vez, ratas inyectadas con un suero heterólogo anti-D-STBM desarrollaron una lesión similar. Por otra parte, se indujo una orquitis severa inmunizando ratas Wistar con un hmogenado testicular homólogo y adyuvantes y se estudiaron las poblaciones linfáticas de los ganglios...