Sperm ultrastructure and spermatogenesis in the Japanese beetle Popillia japonica (Coleoptera, Scarabaeidae).

Popillia japonica is an invasive scarab beetle native to Japan that in 1916 invaded New Jersey in USA. From that moment onwards, the insect has spread invading several US states, Canada, the Azores, Italy and, recently, Switzerland. It is a severe agricultural pest included in the EU priority pest list being able to feed on more than 300 plant species and having an important biotic potential. The general morphology of the reproductive apparatus shows paired testes, each of them having six testicular lobes grouped in threes. From the ventral part of each testicular lobe, each containing about 20 follicles, an efferent vessel originates that fuses with the other efferent vessels to form the deferent duct. A pair of long tubular accessory glands is present. The deferent ducts and accessory glands fuse together into an ejaculatory duct before entering the aedeagus. The sperm is a typical pterygote sperm, 110 µm long, composed of a head and a tail. In the head a three-layered acrosome of about 6 µm in length and a nucleus of about 18 µm long are present. During sperm maturation two C-shaped structures appear in the cytoplasm from the opposite sides of the nucleus that then disappear in late spermatids. In the tail a typical 9 + 9 + 2 flagellar axoneme and two mitochondrial derivatives are present. Moreover, in the head-tail transition region the centriolar adjunct forms a sheath from which three elongated accessory bodies originate. Two of these accessory bodies are placed alongside the axoneme, whilst the third one is placed beneath the mitochondrial derivatives. Mature sperm are grouped in cysts containing about 256 sperm cells. A morphological comparison with related species is provided.

Morphology of ejaculatory ducts: A systematic review.

The morphology of human ejaculatory ducts has not been well established. The objective of this study was to describe macroscopic and microscopic anatomy of ejaculatory ducts. We conducted a systematic review using MEDLINE, Scopus, PubMed, and Cochrane databases. Search terms were: "ejaculatory ducts," "seminal colliculus," "prostatic utricle," "anatomy," "histology," "radiology," and "embryology." We only included studies assessing adult (>18 years) humans published before November 1, 2019. We excluded studies describing pathological ducts and case reports. Independent authors extracted data using predefined criteria. Fourteen studies were included in the qualitative synthesis. Usually, the ejaculatory ducts entered the prostate by piercing the central part of its base. Most studies identified an anteromedial curve of the ducts at the outset within the prostate, their subsequent course being a straight path towards the seminal colliculus, their terminal parts diverging immediately before joining the prostatic urethra. However, the morphology of the terminal part of the ducts was inconsistent. The mean length of the ducts ranged from 1.4 to 2.2 cm. In conclusion, the luminal diameter gradually decreased as the ducts traveled towards the seminal colliculus. Ejaculatory ducts angulate anteromedially at their onset within the prostate and travel straight towards the seminal colliculus. Their terminal parts diverge immediately before joining the prostatic urethra. However, the reported dimensions of the ducts differ among studies.

Morphological and histological structure of the male reproductive system of the water strider Gerris lacustris (Linnaeus 1758) (Gerridae, Heteroptera).

This work presents the male reproductive system morphology and histology of the water strider Gerris lacustris (Linnaeus 1758) (Gerridae, Heteroptera) using light microscopy and scanning electron microscopy. The male reproductive system of G. lacustris comprise of a pair of testes, two vasa deferentia, two seminal vesicles, an ejaculatory duct. There is no bulbus ejaculatorius and the long vas deferantia uniting to form a simple ductus ejaculatorius which is connected to the aedeagus. The testes are white colored and this cylindiric-shaped structure lies along genital abdominal segment. The testicular follicles have three different development zones (growth zone, maturation zone, differentiation zone). Each testis has two follicles, which are not lined by a common peritoneal sheath and involving many cysts arranged in a progressive order of maturation from the distal to the proximal region; spermiogenesis occurs in mature males, finishing with the organization of sperm bundles. The testes are connected to the seminal vesicles, specialized sperm storage places, by the vas deferentia.

Morphostructural analysis of the male reproductive system and DNA barcoding in Balclutha brevis Lindberg 1954 (Homoptera, Cicadellidae).

Balclutha brevis Lindberg 1954 is an allochthonous leafhopper infesting an invasive grass, Pennisetum setaceum, in Sicily and in mainland Europe; therefore, this species could compete with populations of native species, thus contributing to the loss of biodiversity. Considering the ecological implications of B. brevis, investigations on all its biological aspects represent, therefore, a premise for further studies in applied sciences. Based on the lacking ultrastructural data about the reproductive systems of the Auchenorrhyncha, we carried out morphostructural investigations on the male reproductive system of B. brevis. Further, a first report of DNA barcoding analysis (amplification and sequencing of Cytochrome Oxidase I gene) has also been performed to characterize B. brevis compared to other congeneric species. From a morphological point of view, the male reproductive system of B. brevis has an organization comparable to the general anatomical features of most of the Auchenorrhyncha species; however, comparing our data with those concerning the different groups of Cicadomorpha, some considerations are discussed. As for the histological and ultrastructural investigations, our results show a secretory activity of the various examined structures, mainly in the lateral ejaculatory ducts and in the accessory glands. The latter, in particular, show morphostructural differences comparing the distal tract to the proximal one; moreover, the histochemical techniques showed the possible presence of a lipid component in the peculiar cytoplasmic granules found in the gland cells. The significance of these findings in the accessory glands is discussed. Finally, the ultrastructural features found in the seminal vesicles are different from those of the lateral ejaculatory ducts and are indicative of the different roles played by these structures in the organization of the spermatozoa bundles.

Sperm of Galeorhinus galeus (Elasmobranchii, Triakidae) Traverse an Excurrent Duct System Characterized by Pronounced Regionalization: A Scanning Electron and Light Microscopy Study.

The transport and subsequent maturation of spermatozoa in the vertebrate excurrent duct require the creation of a series of biochemically defined luminal milieus along the length of the duct. Such specialization is accomplished, among others, by changes in the epididymal histoarchitecture. Here we show that the intratesticular and extratesticular genital ducts of mating Galeorhinus galeus exhibit pronounced regionalization both in terms of epithelial histology and lumen diameter size. Findings also reveal distinct differences in the manner in which the spermatozoa were found in each segment of the duct. Novel scanning electron microscopy evidence is presented showing that the wide lumen ductuli epididymides, which ultimately convey the spermatozoa to the proximal epididymis, show functional specialization as well. The wall of the former consisted of cuboidal ciliated and nonciliated cells whose spatial arrangement in the duct wall resulted in a luminal surface showing lengthy rows of cilia-free areas, with each row bordered on both sides by a single row of cilia. The proximal epididymis comprised several subregions whose epithelial histology varied widely. The distal epididymis and ampulla of the epididymis possessed many fingerlike projections and transverse septa, respectively. As the main storage site for spermatozoa, the ampulla completed the bundling of spermatozoa into spermatozeugmata. These were circular sperm masses in which the heads of the spermatozoa were aligned side by side and embedded in a seminal matrix, while their tails extended outward. These findings of pronounced regionalization differ greatly from the rather uniform epididymal histology seen in some rays.

Fine structure of the male genital system of the predatory mite Rhagidia halophila (Rhagidiidae, Prostigmata, Actinotrichida).

The male genital system of the actinotrichid mite Rhagidia halophila is described and compared with other mites and arachnids. The large testes are composed of germinal and glandular parts and produce numerous small sperm cells. The glandular parts are connected via a testicular bridge. Spermiogenesis occurs in cysts containing spermatids in equal stages of development. Cysts of spermatids are embedded in huge somatic cells. The nuclei of the spermatids loose their envelope. Mature sperm cells are simple exhibiting a ring-shaped chromatin body and lacking an acrosomal complex. They are most similar to the sperm cells of the related mite Linopodes motatorius. The spermatopositor contains the ejaculatory duct divided into a dorsal channel and a ventral channel that are connected via a narrow passage. At its distal end, the spermatopositor is divided into three eugenital lips. The function of the spermatopositor during deposition of the peculiar thread-like spermatophores is discussed. Details of the sensilla of the spermatopositor and the progenital lips are reported. The genital papillae located on the inner side of the progenital lips exhibit characteristics of cells performing transport of ions and/or water. The results confirm the overall similarity of actinotrichid genital systems, which is profoundly different from that of anactinotrichid mites. With reference to other Arachnida it is corroborated that testes and sperm structure of Actinotrichida are most similar to that of Solifugae. However, synapomorphies between sperm cells of Rhagidia and Solifugae that could suggest a closer relationship between these two taxa as was suggested in earlier studies were not recognizable. On the contrary, the sperm cells of Rh. halophila being devoid of an acrosomal complex appeared to be more apomorphic than those of many other actinotrichid mites as well as Solifugae.

Regional distribution of neuroendocrine cells in the urogenital duct system of the male rat.

BACKGROUND: Neuroendocrine (NE) cells are frequently present in the human prostate and urethra, whereas they are lacking in the other urogenital organs. This study was undertaken as there are only few detailed studies available on the distribution, form and function of NE cells and the structure of excretory ducts of the accessory sex organs in the male rat. METHODS: Systematic gross anatomical dissections were combined with immunohistochemical and electron microscopic studies of the excretory ducts of the urogenital glands in male rats, with particular focus on the distribution and ultrastructure of the NE cells. RESULTS: The topography and structure of the excretory ducts of the different glands were characterized in detail and analyzed for the distribution of NE cells. These are present (in falling frequencies) in the ducts of seminal vesicles and ventral and lateral prostate and are rare in ducts of coagulating gland, dorsal prostate, urethral epithelium, and excretory ducts of the (bulbo) urethral glands. They are absent in the respective glands proper, the deferent duct and ejaculatory ampulla. Approximately 40% of the NE cells of the ventral prostate ducts are of the "open" type, whereas these are less frequent (14%) in the seminal vesicle ducts, where the "closed" type prevails. CONCLUSIONS: NE cells are present in unequal quantities in the excretory ducts of the accessory sex glands, but they are absent in the glands proper and the deferent ducts. This distribution pattern points to a strictly localized function and differentiation potency of NE precursor cells.

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.

The ultrastructure of the ejaculatory duct in the springtail Orchesella villosa (Geoffroy) (Hexapoda, Collembola) and the formation of the spermatophore.

The initial part of the ejaculatory duct of Orchesella villosa contains a "valve" and a "sorter" avoiding respectively the reflow and allowing the separation of the secretion for the spermatophore stalk from the sperm fluid. For most of its length, the ejaculatory duct lumen is divided into two parts: in the dorsal part the sperm fluid flows while in the ventral district the secretion for the stalk occurs. Laterally, on both sides of the duct, longitudinal muscle fibers are present. The epithelium of the dorsal region consists of two types of long secretory cells; the most peculiar of them are those provided with extracellular cisterns flowing directly into the duct lumen as it occurs in 1st type of epidermal cells. These cells could be involved in the control of the viscosity of the sperm fluid. The second type of cells produce a secretion probably involved in the formation of the outer coat of the apical sperm droplet. The ventral epithelium consists of short cells contributing to the enrichment of the secretion for the spermatophore stalk and perhaps also to the viscosity of the secretion flowing in the lumen. In the distal part of the ejaculatory duct, the ventral district is provided with a thick layer of muscle fibers and with 3+3 cuticular laminae dividing the lumen into a series of slits through which the secretion of the stalk is squeezed out into filaments. This organization allows the twisting and hardening of these filaments. A drop of sperm fluid is laid on top of the long and rigid spermatophore stalk.

Internal anatomy and ultrastructure of the male reproductive system of the spider crab Maja brachydactyla (Decapoda: Brachyura).

The morphology and function of the male reproductive system in the spider crab Maja brachydactyla, an important commercial species, is described using light and electron microscopy. The reproductive system follows the pattern found among brachyuran with several peculiarities. The testis, known as tubular testis, consists of a single, highly coiled seminiferous tubule divided all along by an inner epithelium into germinal, transformation, and evacuation zones, each playing a different role during spermatogenesis. The vas deferens (VD) presents diverticula increasing in number and size towards the median VD, where spermatophores are stored. The inner monostratified epithelium exocytoses the materials involved in the spermatophore wall formation (named substance I and II) and spermatophore storage in the anterior and median VD, respectively. A large accessory gland is attached to the posterior VD, and its secretions are released as granules in apocrine secretion, and stored in the lumen of the diverticula as seminal fluids. A striated musculature may contribute to the formation and movement of spermatophores and seminal fluids along the VD. The ejaculatory duct (ED) shows a multilayered musculature and a nonsecretory pseudostratified epithelium, and extrudes the reproductive products towards the gonopores. A tissue attached to the ED is identified as the androgenic gland.

Structure of male accessory glands of Bolivarius siculus (fischer) (Orthoptera, Tettigoniidae) and protein analysis of their secretions.

In Tettigoniidae (Orthoptera), male reproductive accessory glands are involved in the construction of a two-part spermatophore; one part, the spermatophylax, is devoid of sperm and considered a nuptial gift. The morphology, ultrastructure, and secretion protein content of the male reproductive accessory glands from Bolivarius siculus were investigated. Two main groups of gland tubules open into the ejaculatory duct: the "first-order" glands, a number of large anterior tubules, and the "second-order" glands, smaller and more numerous tubules positioned posteriorly. Along with a further subdivision of the gland tubules, we here describe for the first time an additional gland group, the intermediate tubules, which open between first and second-order glands. The mesoderm-derived epithelium of all glands is a single layer of microvillated cells, which can be either flattened or cylindric in the proximal or distal region of the same gland. Epithelial cells, very rich in RER and Golgi systems, produce secretions of both electron-dense granules and globules or electron-transparent material, discharged into the gland lumen by apocrine or merocrine mechanisms, respectively. With one exception, a unique electrophoresis protein profile was displayed by each of the gland types, paralleling their unique morphologies. To assess the contribution of different types of accessory glands to the construction of the spermatophore, the protein patterns of the gland secretions were compared with those of the extracts from the two parts of the spermatophore. All samples showed bands distributed in a wide range of molecular weight, including proteins of very low molecular mass. However, one major high molecular weight protein band (>180 kDa) is seen exclusively in extracts from the first-order glands, and corresponds to an important protein component of the spermatophylax.

Ultrastructure of male reproductive accessory glands and ejaculatory duct in the Queensland fruit fly, Bactrocera tryoni (Diptera: Tephritidae).

Ultrastructure of male reproductive accessory glands and ejaculatory duct in the Queensland fruit fly (Q-fly), Bactrocera tryoni, were investigated and compared with those of other tephritid flies. Male accessory glands were found to comprise one pair of mesodermic glands and three pairs of ectodermic glands. The mesodermic accessory glands consist of muscle-lined, binucleate epithelial cells, which are highly microvillated and extrude electron-dense secretions by means of macroapocrine transport into a central lumen. The ectodermic accessory glands consist of muscle-lined epithelial cells which have wide subcuticular cavities, lined with microvilli. The electron-transparent secretions from these glands are first extruded into the cavities and then forced out through small pores of the cuticle into the gland lumen. Secretions from the two types of accessory glands then flow into the ejaculatory duct, which is highly muscular, with epithelial cells rich in rough endoplasmic reticulum and lined with a thick, deeply invaginated cuticle. While there are some notable differences, reproductive accessory glands of male Q-flies generally resemble those of the olive fruitfly, Bactrocera oleae, and to a lesser extent the Mediterranean fruit fly, Ceratitis capitata.

Preserved tissue structure of efferent ductules in aromatase-deficient mice.

Estrogen receptor alpha (Esr1) is proposed to play a critical role in the regulation of testicular fluid reabsorption at efferent ductules, and disruption of the Esr1 gene (Esr1(-/-)) resulted in marked dilation of the lumens of efferent ductules. This study was aimed to clarify whether disruption of the gene for aromatase (Ar), an enzyme responsible for estrogen biosynthesis, results in morphological and transcriptional alterations at efferent ductules as observed in Esr1(-/-) mice. Histology demonstrated structural preservation of the ducts in aromatase-deficient (Ar(-/-)) mice. Electron microscopic examinations reveal that endocytic apparatus and tubule-cisternal endoplasmic reticulum are present in non-ciliated cells irrespective of the genotypes. However, electron-dense and acid phosphatase-negative granules and apical tubules, which are components thought to be related to membrane recycling of endosomes, are observed only in wild-type (WT) and Ar(-/-) mice. By contrast, the Golgi complex is highly developed in Esr1(-/-) mice when compared with WT and Ar(-/-) mice. RT-PCR analysis reveals no significant differences in the expression levels of a subset of genes involved in ion transportation. Thus, from the structural and transcriptional points of view, the efferent ductules of Ar(-/-) mice are indistinguishable from those of WT mice. Moreover, data from electron microscopic examinations indicate the possible involvement of Esr1 in the regulation of vesicle recycling processes.

Anatomía microscópica de los conductos eyaculadores. Implicaciones clínicas en el cáncer de próstata / Microscopic anatomy of ejaculatory ducts. Clinical implications in prostate cancer

Antecedentes: Los conductos eyaculadores son dos estructuras anatómicas mayoritariamente intraprostáticas, pero de origen extraprostático, cuya patología, congénita o adquirida, es causa frecuente de esterilidad masculina, lo cual ha justificado la mayoría de estudios clínicos y radiológicos publicados hasta la fecha. Los patólogos tienen un contacto cada vez más frecuente con ellos debido al incremento en el número de prostatectomías radicales, pero su desconocimiento anatómico es grande y la repercusión clínica de su invasión por el cáncer de próstata, poco valorada. Métodos: Se estudian cortes histológicos seriados de 20 próstatas de cadáver y de 37 prostatectomías radicales con invasión de las vesículas seminales, y se describen los hallazgos encontrados en los conductos eyaculadores desde su ingreso en la próstata hasta su desembocadura en la uretra. Resultados: La pared intraprostática de los conductos eyaculadores consta de una capa mixta, circunferencial y longitudinal, de fibroblastos que incluye aisladas fibras musculares lisas longitudinales. Esta capa es individual en su inicio y compartida después, y los separa nítidamente de la próstata. El epitelio es similar al de las vesículas seminales, y la lámina propia contiene nervios, arterias, venas y linfáticos propios. En su parte final, el esqueleto muscular del verumontanum, las glándulas periuretrales locales, el utrículo prostático, y los citados conductos eyaculadores constituyen un laberinto morfológico que está sujeto a múltiples variaciones individuales. La invasión de los mismos por el cáncer de próstata es un hecho poco frecuente que favorece la diseminación extraprostática de la neoplasia. Conclusiones: Por la trascendencia clínica que tiene su invasión por el cáncer de próstata, los conductos eyaculadores deben ser incluidos de manera rutinaria, y evaluados intencionadamente en el estudio de las piezas de prostatectomía radical

Background: Ejaculatory ducts are two intraprostatic anatomical structures with an extraprostatic origin which are frequently involved in male sterility. This fact is the cause of most of the clinical and radiological studies published so far. Today, pathologists are frequently faced with ejaculatory ducts because of the increasing number of radical prostatectomies received in Pathology Labs, but its detailed knowledge is not generalised and its clinical impact underestimated. Methods: Consecutive histological slides of the prostate obtained from 20 human cadavers and 37 radical prostatectomies with prostate cancer invading the seminal vesicles were studied paying special attention to the ejaculatory ducts, from its entrance in the prostate to its end in the verumontanum. Results: The intraprostatic wall of ejaculatory ducts is composed by a double sheath (longitudinal and circumferencial) of fibroblasts including some longitudinal smooth muscle fibres. This sheath is individual at the beginning and later common to both ducts, and clearly separates the ejaculatory ducts from the prostatic tissue. The epithelium is similar to that of seminal vesicles, and the lamina propria contains nerves, arteries, veins and lymphatics. The skeletal muscle of the verumontanum, the local periurethral glands, the prostatic utricle, and the ends of both ejaculatory ducts constitute a morphological labyrinth with wide individual variations. The ejaculatory duct invasion by prostate cancer is a rare event that favours the extraprostatic extension. Conclusions: Due to the clinical importance of the ejaculatory duct invasion by prostate cancer, these structures should be sampled in depth and evaluated intentionally in the routine practice

Anatomía microscópica de los conductos eyaculadores. Implicaciones clínicas en el cáncer de próstata / Microscopic anatomy of ejaculatory ducts. Clinical implications in prostate cancer

Antecedentes: Los conductos eyaculadores son dos estructuras anatómicas mayoritariamente intraprostáticas, pero de origen extraprostático, cuya patología, congénita o adquirida, es causa frecuente de esterilidad masculina, lo cual ha justificado la mayoría de estudios clínicos y radiológicos publicados hasta la fecha. Los patólogos tienen un contacto cada vez más frecuente con ellos debido al incremento en el número de prostatectomías radicales, pero su desconocimiento anatómico es grande y la repercusión clínica de su invasión por el cáncer de próstata, poco valorada. Métodos: Se estudian cortes histológicos seriados de 20 próstatas de cadáver y de 37 prostatectomías radicales con invasión de las vesículas seminales, y se describen los hallazgos encontrados en los conductos eyaculadores desde su ingreso en la próstata hasta su desembocadura en la uretra. Resultados: La pared intraprostática de los conductos eyaculadores consta de una capa mixta, circunferencial y longitudinal, de fibroblastos que incluye aisladas fibras musculares lisas longitudinales. Esta capa es individual en su inicio y compartida después, y los separa nítidamente de la próstata. El epitelio es similar al de las vesículas seminales, y la lámina propia contiene nervios, arterias, venas y linfáticos propios. En su parte final, el esqueleto muscular del verumontanum, las glándulas periuretrales locales, el utrículo prostático, y los citados conductos eyaculadores constituyen un laberinto morfológico que está sujeto a múltiples variaciones individuales. La invasión de los mismos por el cáncer de próstata es un hecho poco frecuente que favorece la diseminación extraprostática de la neoplasia. Conclusiones: Por la trascendencia clínica que tiene su invasión por el cáncer de próstata, los conductos eyaculadores deben ser incluidos de manera rutinaria, y evaluados intencionadamente en el estudio de las piezas de prostatectomía radical

Background: Ejaculatory ducts are two intraprostatic anatomical structures with an extraprostatic origin which are frequently involved in male sterility. This fact is the cause of most of the clinical and radiological studies published so far. Today, pathologists are frequently faced with ejaculatory ducts because of the increasing number of radical prostatectomies received in Pathology Labs, but its detailed knowledge is not generalised and its clinical impact underestimated. Methods: Consecutive histological slides of the prostate obtained from 20 human cadavers and 37 radical prostatectomies with prostate cancer invading the seminal vesicles were studied paying special attention to the ejaculatory ducts, from its entrance in the prostate to its end in the verumontanum. Results: The intraprostatic wall of ejaculatory ducts is composed by a double sheath (longitudinal and circumferencial) of fibroblasts including some longitudinal smooth muscle fibres. This sheath is individual at the beginning and later common to both ducts, and clearly separates the ejaculatory ducts from the prostatic tissue. The epithelium is similar to that of seminal vesicles, and the lamina propria contains nerves, arteries, veins and lymphatics. The skeletal muscle of the verumontanum, the local periurethral glands, the prostatic utricle, and the ends of both ejaculatory ducts constitute a morphological labyrinth with wide individual variations. The ejaculatory duct invasion by prostate cancer is a rare event that favours the extraprostatic extension. Conclusions: Due to the clinical importance of the ejaculatory duct invasion by prostate cancer, these structures should be sampled in depth and evaluated intentionally in the routine practice

Excurrent duct system of the male turtle Chrysemys picta.

The epididymis and efferent duct system of the turtle Chrysemys picta were examined. Seminiferous tubules are drained by a series of ducts that form a rete exterior to the tunica albuginea. The rete is located lateral to the testis and consists of anastamosing tubules of varying diameters, lined by a simple epithelium consisting of squamous to cuboidal cells. The rete is highly vascularized. A series of tubules (efferent ductules) connect the rete to the epididymis proper. The efferent ductules are highly convoluted, running between the epididymal tubules and are of varying diameters. The simple columnar epithelium lining these tubules possesses tight junctions, with every third or fourth cell possessing long cilia that protrude into the lumen. The cytoplasm of these epithelial cells contains abundant mitochondria. In the central portion of the efferent ductule, epithelial cells possess granules that appear to be secreted into the lumen by an apocrine process. The epididymis proper is a single, long, highly convoluted tubule that receives efferent ductules along its entire length. It is lined by a pseudostratified epithelium containing several cell types. The most abundant cell (vesicular cell) lacks cilia, but has a darkly staining apical border due to numerous small vesicles immediately beneath the luminal membrane. The small vesicles appear to fuse with each other basally to form larger vesicles. These cells appear to have an absorptive function, and occasionally sperm are embedded in their cytoplasm. The second-most abundant cell is a basal cell found along the basement membrane. The number of these cells fluctuates throughout the year, being most abundant in late summer and early fall. A small narrow cell with an oval nucleus and darkly staining cytoplasm, extending from the basement membrane to the apical surface, is present in small numbers, particularly in the caudal regions of the epididymis. This cell is frequently found in association with another narrow cell having a rounded nucleus and abundant mitochondria in its cytoplasm.

Ultrastructure of the ducts of the reproductive tract of males of Melipona bicolor bicolor lepeletier (Hymenoptera, Apinae, Meliponini).

The present paper describes the ultrastructural features of seminal vesicle, post-vesicular vas deferens and ejaculatory duct of Melipona bicolor bicolor from newly emerged and mature males. Although the results do not show very consistent morphological signs of secretory activity by the epithelium of these organs, lipidic droplets and lamellar granules present in mature males' seminal vesicles and the vacuoles present in post-vesicular vas deferens are probably secretion. Besides, the spermatozoa in the lumen are immersed in a material of characteristic structure, which must be produced in superior regions of the reproductive system of immature males, not studied here. The presence of sperm cells, apparently in cytoplasm vesicles of seminal vesicle and post-vesicular vas deferens, suggests spermiophagy by their epithelium.

Estrogen receptor alpha has a functional role in the mouse rete testis and efferent ductules.

Previous studies of the estrogen receptor-alpha knockout (alpha ERKO) in the male mouse demonstrate that the rete testis and efferent ductules are targets of estrogen. Because the alpha ERKO mouse lacks a functional estrogen receptor alpha (ER alpha) throughout development, it was not known whether the morphological and physiological abnormalities observed in the alpha ERKO male were due to developmental defects or to dysfunctions concurrent with the lack of ER alpha in the tissue. This study was designed to determine if treatment of normal wild-type (WT) mice with the pure antiestrogen, ICI 182,780, (ICI) could reproduce the morphological characteristics seen in alpha ERKO mice. Thirty-day-old male mice were treated for 35 days with either castor oil or ICI. Age-equivalent alpha ERKO mice were used for comparison. Light microscopic examinations of the reproductive tracts revealed dramatic changes in the efferent ductules of treated mice: a 1.7-fold increase in luminal diameter, a 56% reduction in epithelial cell height, a 60% reduction in brush boarder height of nonciliated cells, and an apparent reduction of the number of observable lysosomes and endocytotic vesicles. Testes of ICI-treated mice showed swollen rete testes area (6.5 times larger than control) and a 65% reduction in rete testis epithelium height. However, there were no significant changes in body and testis weights. These results indicate that ER blockage with ICI in WT mice results in morphological changes of the efferent ductules resembling those seen in alpha ERKO siblings of the same age. Based on this study, we conclude that ER alpha has a functional role in the mouse reproductive tract and the aberrant morphology observed in the efferent ductules of the alpha ERKO mouse is likely the result of a concurrent response to the lack of functional ER alpha, and not solely due to the lack of ER alpha during early developmental times.

Low density lipoprotein receptor-related protein-2 expression in efferent duct and epididymal epithelia: evidence in rats for its in vivo role in endocytosis of apolipoprotein J/clusterin.

Apolipoprotein J/clusterin/sulfated glycoprotein-2 (apo J) disassociates from spermatozoa and is endocytosed by epithelial cells lining the efferent ducts and epididymis. The low density lipoprotein receptor-related protein-2/megalin (LRP-2) has been shown to bind to apo J and mediates its endocytosis and lysosomal degradation in cultured cells. In this study, immunocytological techniques were used to localize LRP-2 in rat efferent ducts and epididymis and to determine whether its expression correlated with those epithelial cells involved in apo J endocytosis. Pronounced LRP-2 immunochemical staining was observed on the apical surfaces of epithelial cells lining the efferent ducts and in the intermediate zone, proximal caput, and corpus and cauda regions of the epididymis. Single immunogold labeling at the electron microscopic level showed LRP-2 to be present within coated pits, endocytic vesicles, and early endosomes of the nonciliated cells of the efferent ducts and the principal cells of the epididymis. In efferent ducts, double immunogold labeling showed both LRP-2 and apo J to be present in endocytic compartments including coated pits, endocytic vesicles, and early endosomes of nonciliated cells. However, while apo J was detected in late endosomes and lysosomes of nonciliated cells, LRP-2 was not. Apical tubules, possibly emerging from late endosomes, contained labeling for LRP-2 but not for apo J. Ciliated cells lying adjacent to nonciliated cells displayed no labeling for either LRP-2 or apo J. These results are consistent with the possibility that LRP-2 serves as an endocytic receptor for apo J in vivo and that after endocytosis the LRP-2 is recycled back to the cell surface while apo J is delivered to the lysosomes for degradation. To provide additional evidence implicating LRP-2 in apo J endocytosis, a receptor-associated protein (RAP), an antagonist of apo J binding to LRP-2, was injected into the efferent duct lumen. Subsequent immunocytological analysis of the efferent duct showed that the RAP treatment abolished the endocytosis of apo J by the nonciliated cells. Taken together, these data indicate that LRP-2 is a likely mediator of apo J endocytosis by the nonciliated efferent duct cells.

Morphological characteristics of boar efferent ductules and epididymal duct.

The aim of the present study was to provide a comprehensive morphological analysis of the porcine epididymis in view of the specific functions being performed in different regions of this organ. Blood supply and microvasculature of efferent ductules and epididymal duct were investigated by means of corrosion casts which were analysed macroscopically and by scanning electron microscopy. This revealed blood supply to the testis and epididymis to be closely related. The capillary pattern was typical for the efferent ductules, the caput, corpus, and distal cauda epididymidis, respectively. Corrosion casts were also used to visualize the course of the efferent ductules themselves. Tissue samples from different regions of the efferent ductules and epididymal duct were examined by light microscopy and both scanning and transmission electron microscopy, with special attention being payed to transitional areas. Morphological criteria allowed the distinction of three segments within the efferent ductules and of the initial segment, proximal caput, distal caput, corpus, proximal cauda, and distal cauda regions of the epididymal duct. Components of the endocytic apparatus of efferent ductule principal cells were identified by ferritin uptake. Ultrastructural evidence of absorption in the epididymal duct was particularly prominent in proximal and distal caput. Extensive cisternae of rough endoplasmic reticulum and a well-developed Golgi apparatus were indicative of active protein synthesis and secretion especially in the distal caput and corpus regions. However, assignment of various organelles in principal cells of the epididymal duct to either absorptive or secretory pathways still remains tentative.