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PubMed1994

Developmental expression of the glutathione S-transferase Yo subunit in the rat testis and epididymis using light microscope immunocytochemistry.

BACKGROUND: Glutathione S-transferases (GSTs) are a family of isozymes that catalyze the conjugation of glutathione with various toxic electrophilic compounds. GSTs are composed of several classes based on the degree of sequence homology of their subunits. The Yo subunit, a member of the mu class, is expressed at high levels in the testis and epididymis. The purpose of this study was to immunolocalize the GST-Yo in these tissues during development. METHODS: The testes and epididymides of rats aged 7, 15, 21, 28, 39, 42, 45, 49, and 56 days were fixed in Bouin's fixative, and immunostained for light microscopic analysis. RESULTS: In the testis the cytoplasm of all germ cells was unreactive until day 39. At that time, step 18 spermatids appeared moderately reactive, while the few observed step 19 spermatids were intensely reactive as were their residual bodies. The presence of residual bodies indicates that spermiation takes place as early as day 39; however, the number of step 19 spermatids is low at this age. A progressive increase in the size of the tubule and number of elongating spermatids was seen between days 42 and 49. In addition, by day 49, a weak staining was observed in steps 12-15, moderate in steps 16-17, and intense in steps 18-19 spermatids. In terms of the intensity of staining, cell types stained, size of the tubules, and number of elongating spermatids, no difference was noted between day 49, 56, and adult animals. Thus Yo protein expression in germ cells reached maturity by day 49. The epithelial cells of the rete testis were intensely reactive at day 7 and remained so throughout development. In contrast, while the epithelial cells of the efferent ducts at day 7 were intensely reactive, they were weakly reactive by day 39 and remained so at later ages. Along the entire epididymis, the columnar epithelial cells showed a moderate apical/supranuclear reaction from day 7 to 28. By day 39 principal cells of the initial segment became weakly reactive, while those in the caput and corpus were moderately stained, a situation seen at later ages including adults. Only by day 49 did principal cells of the proximal cauda become moderately stained as seen in adult animals. Thus the expression of the Yo protein in the principal cells of the proximal cauda may be regulated by different factors than those of the caput and corpus epididymidis. Alternatively, the expression of the Yo subunit in principal cells of the proximal cauda may develop later since this region would be the last to receive luminally derived testicular products. In the initial segment, the decrease in staining of principal cells at day 39 may be due to an inhibiting factor emanating from the testis. Spermatozoa appeared in the lumen of each epididymal region well after the expression of Yo had reached its adult staining pattern indicating that they are not a factor. CONCLUSIONS: Overall these results suggest that the expression of GST-Yo in the various cells of the testis and epididymis are controlled by different factors during postnatal development.

Animals↗

PubMed2002

Cyclical reproductive changes in the non-ciliated epithelia of the epididymis of birds.

The epididymis of two species of domestic birds, the domestic fowl (Gallus domesticus), duck (Anas platyrhynchos), and of domestic and feral guinea-fowl (Numida meleagris) was studied during the three main phases of the reproductive cycle (prepuberal, sexually mature and active, and sexually mature but inactive or resting) with a view to identifying major histological and ultrastructural changes associated with and distinctive for each phase. Rete testis cells accumulated numerous variably sized lipid droplets in all birds, as well as large heterogeneous and lipofuscin-containing dense bodies in the guinea-fowl, during the resting but not in the other phases. The principal or Type III cells of the connecting and epididymal ducts exhibited profound structural changes, including, but not limited to, rarefied cytoplasm, inconspicuous and general loss of sparsely granular endoplasmic reticulum, loss of secretory vesicles in the drake, and an enhanced and conspicuous presence of lipid droplets in the guinea-fowl. The rete cells appeared to be less sensitive than the Type III cells to a reduced level or absence of lumenal androgens. These phase-dependent changes may help to prevent or minimize discrepancies in the interpretation of the normal structure of the epididymis in birds during the sexually active phase, as distinct from the other two phases and their intermediate phases.

Aging↗

PubMed1983

Use of monoclonal antibody techniques to study the ontogeny of bovine anti-Müllerian hormone.

Monoclonal antibodies against bovine anti-Müllerian hormone (AMH) were used to study the hormone in cattle. Anti-Müllerian activity of testicular tissue, immunoreactive testicular AMH, serum AMH concentration and AMH production by incubated testicular tissue were detectable from 42 days, i.e. at the time of seminiferous tubule differentiation, and peaked between 50 and 80 days, when the Müllerian ducts regress in the male fetus. All the values stabilized at a lower level until 30 days after birth and then slowly decreased. At 18 months, only traces of AMH immunoreactivity were detectable in testicular tissue and serum concentration and AMH production by incubated testicular tissue were negligible; the main source of AMH in the adult animal was the rete testis fluid. Study of the disappearance rate of AMH from the serum of castrated calves gave a half-life of approximately 2 days for bovine AMH.

Aging↗

PubMed2001

Benign intratesticular cystic lesions: US features.

Benign intratesticular lesions are rare, but recognition is important to avoid unnecessary surgical intervention. The ultrasonographic (US) features that help differentiate benign from malignant intratesticular lesions are emphasized by the authors. Benign lesions include intratesticular simple cysts, tubular ectasia, epidermoid cyst, tunica albuginea cyst, intratesticular varicocele, abscess, and hemorrhage (infarction). US features of cystic malignant neoplasms that help in differentiation of them from benign cystic lesions are also presented. The US appearance of epidermoid cysts varies with the maturation, compactness, and quantity of keratin present. Of the cystic malignant testicular tumors, which can occur anywhere in testicular parenchyma, teratomas are the most frequent to manifest as cystic masses. An abnormal rind of parenchyma with increased echogenicity usually surrounds these lesions. An intratesticular spermatocele communicates with the seminiferous tubules, whereas simple ectasia of the rete testis does not do so directly. These cysts contain spermatozoa and can be septate. The US findings of intratesticular varicocele are similar to those of extratesticular varicocele and include multiple anechoic, serpiginous, tubular structures of varying sizes. Improvements in gray-scale and Doppler US technology allow subtle distinctions between benign and malignant testicular lesions that were not possible a decade earlier.

Abscess↗

PubMed1983

Demonstration of fluid-phase endocytosis in epithelial cells of the male reproductive system by means of horseradish peroxidase-colloidal gold complex.

The occurrence of fluid-phase endocytosis in Sertoli cells as well as epithelial cells of the rete testis and ductuli efferentes was demonstrated by use of horseradish peroxidase combined with colloidal gold (HRP-G) as a tracer. The characteristic electron dense spherical colloidal gold particles facilitate the localization of the HRP-G complex in pinocytotic vesicles, multivesicular bodies, and lysosomes of these epithelial cells. With this method, which does not require the use of diaminobenzidine, a clear distinction can be made between peroxidases from endogenous and exogenous origins.

Animals↗

PubMed2001

Establishment of the urogenital junction in the male bovine embryo: an ultrastructural study.

The ultrastructure of the developing extratesticular rete testis, the efferent ductules and the establishment of the urogenital junction were studied in bovine embryos and fetuses of 41 through 95 days post conceptionem. The efferent ductules originate as a new set of secondary mesonephric tubules from the dorsal aspect of the nephric giant corpuscle and grow in the direction of the Wolffian duct. Cytological differentiation of the efferent ductules proceeds in a proximo--distal direction. At about 50-60 days, the simple columnar epithelium of the proximal portions of the efferent ductules already consists of the two typical cell types, i.e. reabsorptive principal cells with an endocytotic apparatus and a brush-border and ciliated cells. The lumen of the proximal portion is temporarily filled with intraductular blood vessels and perivascular tissue which may represent vestigial rudiments of glomeruli associated with the efferent ductules. At 50 to 60 days, the extratesticular rete still has a blastema--like appearance and consists of irregular cells with abundant glycogen. Extensions of the extratesticular rete come into contact with the efferent ductules and create the first end-to-side anastomoses with the latter. Somewhat later, the separating basal laminas vanish and invading rete cells intermingle with the epithelium of the efferent ductules, thus establishing the urogenital junction.

Animals↗

PubMedDate not supplied

Excurrent duct system in male rabbit: a morphological study.

The present study was carried out to determine the detailed histological and cytological features of the excurrent ducts of the male reproductive system in the rabbit. The rete testis is comprised of flattened epithelium surrounding a wide lumen which is devoid of spermatozoa. Vasaefferentia epithelium is comprised mainly of ciliated and non-ciliated cells and the lumen is devoid of sperms. On the basis of the characteristics of the epithelium, and luminal contents and histometric observations such as luminal diameter, epithelial cell height and stereocilia height, seven regions of epididymis were identified. Similarly, the vas deferens was identified into 3 regions; proximal, distal and terminal. Results were discussed bearing in mind the functional significance of different regions.

Animals↗

PubMed1985

Variability in the apparent molecular weight of inhibin.

An in vitro bioassay based on suppression of GnRH-stimulated FSH secretion by pituitary cells in culture was used to monitor inhibin activity after dialysis, gel filtration or polyacrylamide gel electrophoresis of protein preparations from a variety of gonadal secretions and extracts under native and dissociating conditions. The suggestion that inhibin is a peptide of molecular weight less than 5000 was not confirmed. Although some fractions of low molecular weight suppressed FSH secretion, the amount of activity was low and the dose response curves were not parallel with a standard preparation of inhibin. Under most conditions, inhibin eluted with an apparent molecular weight of about 90 000. However, gel filtration of rete testis fluid protein in 1 M acetic acid resulted in elution of inhibin activity with a lower apparent molecular weight and with polyacrylamide gel electrophoresis in 0.1% (w/v) sodium dodecylsulfate, the apparent molecular weight was 30 000. It is concluded that inhibin is a protein which tends to aggregate and coelute with larger molecules.

Animals↗

PubMed2000

Proliferative lesions and reproductive tract tumors in male descendants of mice exposed developmentally to diethylstilbestrol.

Prenatal exposure to diethylstilbestrol (DES) is associated with reproductive tract abnormalities, subfertility and neoplasia in experimental animals and humans. Studies using experimental animals suggest that the carcinogenic effects of DES may be transmitted to succeeding generations. To further evaluate this possibility and to determine if there is a sensitive window of exposure, outbred CD-1 mice were treated with DES during three developmental stages: group 1 was treated on days 9-16 of gestation (2.5, 5 or 10 microg/kg maternal body weight) during major organogenesis; group II was treated once on day 18 of gestation (1000 microg/kg maternal body weight) just prior to birth; and group III was treated on days 1-5 of neonatal life (0.002 microg/pup/day). DES-exposed female mice (F(1)) were raised to maturity and bred to control males to generate DES-lineage (F(2)) descendants. The F(2) males obtained from these matings are the subjects of this report; results in F(2) females have been reported previously [Newbold et al. (1998) CARCINOGENESIS:, 19, 1655-1663]. Reproductive performance of F(2) males when bred to control females was not different from control males. However, in DES F(2) males killed at 17-24 months, an increased incidence of proliferative lesions of the rete testis and tumors of the reproductive tract was observed. Since these increases were seen in all DES treatment groups, all exposure periods were considered susceptible to perturbation by DES. These data suggest that, while fertility of the DES F(2) mice appeared unaltered, increased susceptibility for tumors is transmitted from the DES 'grandmothers' to subsequent generations.

Animals↗

PubMed1990

Sertoli cells, proximal convoluted tubules in the kidney, and neurons in the brain contain cyclic protein-2.

We analyze by immunocytochemistry the in vivo distribution in rat Sertoli cells of Cyclic Protein-2 (CP-2), which is maximally synthesized and secreted in vitro at stages VI and VII of the cycle of the seminiferous epithelium. This analysis demonstrates that CP-2 staining is strongest in Sertoli cells in stage VI and VII tubules. Additionally, we demonstrate that the staining for CP-2 within a stage VII tubule differs from the staining of another Sertoli cell secretory product, androgen-binding protein. CP-2 is not detected by immunocytochemistry in any other tissues of the reproductive tract, though immunoblot analysis demonstrates the presence of CP-2 in rete testis and epididymal fluids. CP-2 was immunocytochemically detected in only three other organs: the kidney, the brain (with greatest concentration in the supraoptic and paraventricular nuclei), and the posterior pituitary. The presence of CP-2 in the kidney was confirmed by metabolic radiolabeling, immunoprecipitation, and peptide analysis. The presence of CP-2 in the brain was confirmed by immunoblot analysis of radioinert protein immunoprecipitated from the anterior hypothalamus.

Androgen-Binding Protein↗

PubMed1976

Ultrastructure of testes and excurrent ducts in the bonnet monkey (Macaca radiata).

The testes and excurrent ducts of four bonnet macaques (Macaca radiata) were examined using scanning and transmission electron microscopy. The three layers of contractile and connective tissue composing the tunica albuginea, and the multilayered tunica propria of the seminiferous tubules were similar to that of man. Spermatids project from the epithelium or are found free in the lumen. The stages of the cycle of the germinal epithelium in the bonnet macaque were similar to that in other macaques. The epithelium of the rete testis consisted of thin brush-bordered cells, whereas the epithelium of the efferent ducts consisted of tall, prismatic or cylindrical cells lined by kinocillia or short stereocilia and basal cells. The height of the epididymal epithelium and lumen diameter was maximal in the caput region and minimal at the cauda. Spermatozoa were found among clusters of stereocilia. The epithelium of the vas deferens showed gradual transition from the stereocilia covering typical of the epididymis to that of a shorter, apical microvilli covering.

Animals↗

PubMed1980

[Scanning electron microscopy of the human male genital tract].

The three-dimensional features of the human male genital tract (rete testis, ductuli efferentes, ductus epididymis and vas deferens) and seminal vesicles epithelium have been studied by scanning electron microscopy. The luminal surface of the epithelial cells shows a particular pattern in the different organs, especially for the development of the microvilli and for the nature of the secretion. Particularly, while the columnar cells of the ductus epididymis and vas deferens present a secretory activity, microapocrine in nature, the seminal vesicles epithelium is characterized by a merocrine secretion. The present results are discussed in relation to the previous observations obtained by light microscopy and transmission electron microscopy.

Epididymis↗

PubMed1984

Resorption versus secretion in the rat epididymis.

Micropuncture samples were taken from the rete testis, caput epididymidis and cauda epididymidis of anaesthetized adult rats and assayed for total protein, sodium and potassium concentrations. Intraluminal sperm concentrations were determined and used to calculate the amount of fluid resorbed from the efferent duct and epididymal lumen. It was demonstrated that large amounts of protein (30.2 mg/ml cauda volume) and sodium (241.8 mequiv./l) and smaller amounts of potassium (19.4 mequiv./l) are resorbed from the rat epididymal lumen between the caput and corpus epididymidis. This occurs despite increases in intraluminal concentrations of protein (from 22 to 28 mg/ml) and potassium (from 16 to 50 mequiv./l). Resorption is an important aspect of epididymal control of the intraluminal environment.

Absorption↗

PubMed1984

Light and electron microscopical observations on the male excurrent duct system of the common shrew (Sorex araneus).

In sexually active common shrews (Sorex araneus) the rete testis is a simple sac-like structure situated superficially between the equator and the anterior pole of the testis, and its epithelium glycogen-rich cells. In the ductuli efferentes, the tight junctions of the epithelial cells are poorly developed. The epididymis can be divided cytologically into initial, middle and terminal segments, and some variations are apparent in the fine structure of the principal cells throughout the duct. In the initial segment and in the most proximal part of the middle segment, mitochondrion-rich cells occur sporadically in the epithelium. The ductus deferens is divided into three anatomical regions, a tortuous pars epididymica, a straight middle portion, and an ampullary region. The distal half of the straight portion is distended, and appears to function, together with the terminal segment of the epididymis, as a sperm reservoir.

Animals↗

PubMed1987

[Structure of the efferent ductules of the domestic pig (Sus scrofa domestica)].

The ductuli efferentes of the pig have 2 distinct and continuous segments: the proximal or intratesticular segment that is formed in sequence to the labyrinthic portion of the rete testis, on the cranial extremity of the testis, and the distal or epididymal segment that forms the Cani vasculosi or Lobuli epididymidis. The testicular ductuli are more thicker and the epididymal ductuli are more thin, long and flexuous. The last segment is very coiled and forms a bulboid structure that is placed in the head of the epididymis, in which the ductuli jumped into the initial segment of the epididymis. Each efferent duct is formed by a single and cuboidal/columnar epithelium in which are identified three cellular types: ciliated cells, non ciliated cells and intra-epithelial lymphocytes. The epithelial lining rests on a conspicuous basement membrane that is surrounded by collagen fibrils. Among the ductuli is identified a loose connective tissue.

Animals↗

PubMed1997

A role for oestrogens in the male reproductive system.

Oestrogen is considered to be the 'female' hormone, whereas testosterone is considered the 'male' hormone. However, both hormones are present in both sexes. Thus sexual distinctions are not qualitative differences, but rather result from quantitative divergence in hormone concentrations and differential expressions of steroid hormone receptors. In males, oestrogen is present in low concentrations in blood, but can be extraordinarily high in semen, and as high as 250 pg ml(-1) in rete testis fluids, which is higher than serum oestradiol in the female. It is well known that male reproductive tissues express oestrogen receptors, but the role of oestrogen in male reproduction has remained unclear. Here we provide evidence of a physiological role for oestrogen in male reproductive organs. We show that oestrogen regulates the reabsorption of luminal fluid in the head of the epididymis. Disruption of this essential function causes sperm to enter the epididymis diluted, rather than concentrated, resulting in infertility. This finding raises further concern over the potential direct effects of environmental oestrogens on male reproduction and reported declines in human sperm counts.

Animals↗

PubMed1992

Blind-ending tubules and branching patterns of the rat ductuli efferentes.

The ductuli efferentes of Sprague-Dawley rats were studied by microdissection and microscopic evaluation to document the presence of blind-ending tubules (ductuli aberrantes) and to describe morphological and ultrastructural differences between normally open ductules and blind-ending tubules. The branching patterns of the ductuli efferentes varied considerably between animals. A majority of the animals studied had either six or seven ductuli connected to the rete testis, with some animals having as few as four or as many as eight. Pairs of ductules began merging in the conus vasculosa, ultimately forming a single terminal duct within the capsule of the initial segment epididymidis. In a majority of animals, the junctions were unequally matched and located at various positions within the conus. Blind-ending tubules, found in 60% of the animals, were surrounded by thick connective tissue, and had a smaller diameter (78.7 +/- 1.4 microns) than normal ductules in the conus vasculosa (119.5 +/- 2.1 microns) or the terminus (102.2 +/- 1.5 microns). The lumina of blind-ending tubules were contracted and did not contain sperm. Nonciliated cells in the epithelium of blind-ending tubules contained fewer PAS-positive granules and electron-dense bodies (lysosomes) than nonciliated cells in normal ductules. Consideration of these characteristics will prevent blind-ending tubules from being mistaken for pathological changes in efferent ductules.

Animals↗

PubMed2006

Primary testicular lesions are associated with testicular germ cell tumors of adult men.

The present study aims to establish the nature and frequency of testicular lesions in the parenchyma adjacent to testicular germ cell tumors (TGCT) to improve understanding of the factors involved in the development of testicular cancer. Fifty-three cases of TGCT that were fixed in both neutral-buffered formalin and Bouin solution, allowing for the nuclear characterization of Sertoli cells (SCs), were included in this study. In each case, at least 3 sections of different areas of preserved parenchyma surrounding the TGCT were studied. We found Leydig cell hyperplasia, microlithiasis, angiopathy, adenomatous hyperplasia of the rete testis, SC nodules, SC dysgenesis and involution, SC-only tubules, tubular atrophy, adluminal compartment lesions, hypospermatogenesis associated with spermatocyte sloughing, spermatogonial maturation arrest, and hypertrophic and multinucleated spermatogonia. These lesions were found in regions both adjacent and far away from the tumoral mass, and abnormal seminiferous tubules were found intermingled with those showing complete spermatogenesis, suggesting that these lesions are primary and existed before the development of the tumor. Our study suggests that SCs might play a more important role in the development of testicular tumors than previously thought. Our data supports the hypothesis that there is an abnormal differentiation of SCs, caused either by genetic anomalies or by environmental agents during fetal life. This abnormal SC differentiation may cause not only primary spermatogenesis failure and spermatogenesis arrest at different levels, but may also contribute to the poor differentiation of gonocytes into spermatogonia. The abnormal gonocyte differentiation might favor the development of dysplastic germ cells that may later transform into intratubular germ cell neoplasia, unclassified type.

Adolescent↗