Histological structure and age-related changes in the luminal diameter of the excurrent duct system of guinea cocks (Numida meleagris) and associated changes in testosterone concentrations

As little information is available on the reproductive system of guinea fowl (Numida meleagris), a study was conducted on 49 male guinea fowl to document the histological structure and developmental changes in the luminal diameter of the ducts within the excurrent duct system and associated changes in concentrations of testosterone. Age-related changes were analyzed using the Kruskal-Wallis test and medians separated by the Mann-Whitney U-test. Tubuli recti were clearly visible in the guinea fowl and the rete testes were both intracapsular and extracapsular. Regardless of age, the luminal diameter of the proximal ductuli efferentes was the largest, while that of the connecting duct was the smallest. The luminal diameter of all ducts within the epididymal region increased (P < 0.001) monthly until 20 wk of age, and then increased marginally every month thereafter. Peripheral testosterone concentrations also peaked at 20 wk of age and declined thereafter. In adult birds, the ductus deferens enlarged posteriorly, from an average of about 279 μm cranially to 678 μm caudally. Peripheral testosterone concentrations strongly and positively correlated with the luminal diameter of ducts within the excurrent duct system. The pattern of increase in the luminal diameter of all ducts followed the pattern of testosterone secretion in these birds, which indicates that testosterone concentrations may be closely related to the development of the excurrent duct system in male guinea fowl.

SLC9A3 Protein Is Critical for Acrosomal Formation in Postmeiotic Male Germ Cells

Solute carrier family 9 isoform 3 (SLC9A3), a Na⁺/H⁺ exchanger, regulates the transepithelial absorption of Na⁺ and water and is primarily expressed on the apical membranes of the intestinal epithelium, renal proximal tubule, epididymis, and vas deferens. Loss of the Slc9a3 allele in mice enhances intestinal fluid and causes diarrhoea as a consequence of diminished Na⁺ and HCO₃⁻ absorption. Hence, the loss also causes male infertility and reveals the abnormal dilated lumen of the rete testis and calcification in efferent ductules. However, whether loss of Slc9a3 alleles also disrupts mammalian spermatogenesis remains unknown. First, through immunoblotting, we determined that SLC9A3 is highly expressed in the murine testis compared with the small intestine, epididymis, and vas deferens. During murine spermatogenesis, SLC9A3 is specifically expressed in the acrosome region of round, elongating, and elongated spermatids through immunostaining. Furthermore, SLC9A3 signals are enriched in the acrosome of mature sperm isolated from the vas deferens. In Slc9a3 knockout (KO) mice, compared with the same-aged controls, the number of spermatids on the testicular section of the mice progressively worsened in mice aged 20, 35, and 60 days. Sperm isolated from the epididymis of Slc9a3 KO mice revealed severe acrosomal defects. Our data indicated that SLC9A3 has a vital role in acrosomal formation during spermiogenesis.

Transcriptomic Analysis of Male Black Tiger Shrimp (Penaeus monodon) After Polychaete Feeding to Enhance Testicular Maturation

To reveal molecular mechanism of how polychaetes enhanced reproductive maturation in the male black tiger shrimp (Penaeus monodon), transcriptomic profiles of male reproductive organs (testes and vas deferens) between polychaete-fed and commercial pellet-fed male brooders were compared using cDNA microarray. The overall profiles were distinguishingly different between the two feed groups as well as between testes and vas deferens. Additionally, six of 11 differentially expressed gene identified by the microarray (HNRPUL1 and GCP4 in testes, MAT2B, CDC16, and CSN5 in vas deferens, and SLD5 in both organs) were validated by quantitative real-time PCR (qPCR) and found to exhibit significantly higher expression levels in polychaete-fed shrimp than those in commercial pellet-fed shrimp. From microarray and qPCR results, the differentially expressed transcripts in both testes and vas deferens between different feeds belonged to DNA replication and microtubule nucleation pathways. Interestingly, while the transcripts involved in nutrient uptake and nucleotide biosynthesis were increased only in testes, those involved in protein refolding and apoptosis were increased only in vas deferens. These findings suggest that polychaetes may enhance spermatogenesis by increasing spermatogonia proliferation in testes and by regulating mature spermatozoa in vas deferens.

Bi-species imposex monitoring in Galicia (NW Spain) shows contrasting achievement of the OSPAR Ecological Quality Objective for TBT

Imposex is decreasing worldwide after the total ban on tributyltin (TBT) from antifouling paints. In order to assess improvement in the NE Atlantic, the OSPAR Convention designed an Ecological Quality Objective (EcoQO) based on the VDSI (vas deferens sequence index, an agreed measure of imposex) in the rock snail Nucella lapillus; wherever this is not available, the mud snail Nassarius reticulatus was proposed as a proxy. We determined VDSI in Galician populations of rock (n≥34) and mud (n≥18) snails at regular intervals from pre-ban times until 2009 and 2011, respectively. While imposex in the former started decreasing in 2006 and by 2009 the EcoQO had been met in the area, VDSI in the latter was not significantly reduced until 2011 and values contradict such an achievement. This suggests that the OSPAR imposex bi-species scheme may not be of direct application in the current post-ban scenario.

Expression of thep63and Notch Signaling Systems in Rat Testes During Postnatal Development: Comparison With Their Expression Levels in the Epididymis and Vas Deferens

The role of tubular structures that contribute to the passage of spermatozoa is not solely passive; these structures actively contribute to their own functions, although these tubules and ducts are contiguous and collaborate in the development of the male gamete along their lengths. The testis has the specific function to generate spermatozoa and spermatozoa undergo numerous changes as they pass through the epididymis. A member of the p53 family of genes, p63, is highly expressed in the basal layers of epithelial tissues and plays a key role in maintaining their cell populations, whereas Notch 1 and its ligand Jagged 2 have an important role in the differentiation of germ cells and Jagged 2 is up-regulated by TAp63, one of the p63 isoforms, which transactivates p53 target genes and induces apoptosis. Although the presence of p63 in most epithelia is established, the role of p63 and its possible relationship with the Notch system in the seminiferous epithelium have not been examined. Therefore, we investigated the expression of p63, Jagged 2, and Notch 1 in the testis during postnatal development in comparison with their expression levels in the vaso-epididymal epithelium. In the testis, the expression of TAp63 mRNA increased at day 14 after birth and the expressions of Jagged 2 and Notch 1 mRNA increased at day 16 after birth, suggesting that TAp63-mediated Jagged 2 induction activates the Notch signaling system. On the other hand, the strong signal of DeltaNp63 mRNA was already recognized in the vas deferens at day 0 after birth and advanced chronologically along the duct to the caput epididymis and p63 protein was expressed in basal cells in their epithelium, whereas the mRNAs of Jagged 2 and Notch 1 were maintained at a low level. Consequently, examination of our data raises the probability that TAp63 has an important role for maintenance of germ cell numbers, triggering or balancing the development, differentiation, and apoptosis of germ cells in the testis, which is completely different from the role of DeltaNp63 in other epithelial tissues.

Cloning and characterization of retinoid X receptor (RXR) isoforms in the rock shell, Thais clavigera

The organotin compounds tributyltin (TBT) and triphenyltin (TPT) belong to a diverse group of widely distributed environmental pollutants that induce imposex in gastropods. These organotins have high affinity for retinoid X receptor (RXR), which is a transcription factor activated by retinoids, such as 9-cis retinoic acid (9cRA), in vertebrates. However, the molecular mechanisms underlying the regulation of RXR by retinoids and organotins have not been clarified in gastropods. We isolated two isoforms of RXR cDNAs, RXR isoform 1 (TcRXR-1) and RXR isoform 2 (TcRXR-2), in the rock shell Thais clavigera. The deduced amino acid sequences of TcRXR-1 and TcRXR-2 are highly homologous with those of other gastropods. These TcRXR isoforms displayed 9cRA-dependent activation of transcription in a reporter gene assay using COS-1 cells. The transcriptional activity of TcRXR-2, the encoded protein of which has five additional amino acids in the T-box of the C domain, was significantly lower than that of TcRXR-1. Decreases of the transcriptional activity by TcRXR-1 were observed when more than equal amount of TcRXR-2 fused expression vector was existed in a co-transfection assay. Immunoblot analysis showed several shifted bands for TcRXR isoforms resulting from phosphorylation. Mutation of potential phosphorylation sites from serine to alanine in the A/B domain of TcRXR-1 showed that, in the S89A/S103A mutant, there was a band shift and significantly higher transcriptional activity than in the controls when stimulated with 9cRA. Our findings could contribute to a better understanding of the role of interactions between RXR and retinoids and organotins, not only in the induction mechanism of imposex in gastropods but also in the endocrinology of mollusks.

Exposure to 9-cis retinoic acid induces penis and vas deferens development in the female rock shell, Thais clavigera

To clarify how tributyltin (TBT) and triphenyltin (TPT) interact with the retinoid X receptor (RXR) to induce growth of male sex organs in female gastropods, we treated female rock shells (Thais clavigera) with three different concentrations (0.1, 1, or 5 microg/g wet wt) of 9-cis-retinoic acid (9CRA) or with a single concentration (1 microg/g wet wt) of TBT, TPT, or fetal bovine serum (as a control). The effects of each treatment were measured as the incidence of imposex, the length of the penis-like structure, and the vas deferens sequence (VDS) index. 9CRA induced imposex in a dose-dependent manner; imposex incidence was significantly higher in the rock shells that received 1 (P < 0.05) or 5 microg (P < 0.001) 9CRA than in the controls. After 1 month, the rock shells treated with 5 microg 9CRA exhibited substantial growth of the penis-like structure that was not as evident in the other treated shells. The length of the structure differed between the 0.1- and 5-microg 9CRA treatment groups (P < 0.05) but not between the 1- and 5-microg 9CRA treatment groups (P > 0.05). Compared with the control, the VDS index increased significantly in the 1- (P < 0.05) and 5-microg (P < 0.001) 9CRA groups. The penis-like structures behind the right tentacle in female rock shells treated with 5 microg 9CRA were essentially the same as the penises and vasa deferentia of normal males and of TBT-treated or TPT-treated imposexed females. These results further support the hypothesis that imposex in gastropods could be mediated by RXR.

Imposex levels in the dogwhelk Nucella lapillus (L.)--continuing improvement at high latitudes

In 1990, restrictions on the use of tributyltin (TBT)-based antifouling paints were implemented in Iceland. A previous study showed that the level of imposex in the dogwhelk, Nucella lapillus, in Icelandic waters had decreased significantly between 1992 and 1998. In this study, we repeated the survey on imposex in N. lapillus at 33 locations from the Icelandic coast in 2003. The results indicated that both Vas Deferens Sequence Index (VDSI) and Relative Penis Size Index (RPSI) had further declined in 13 locations since 1998. Among these 13 sites, RPSI was reduced to zero in five cases. While improvements from 1992/1993 to 1998 were seen in reduced levels of imposex near both large and small harbours, the pattern from 1998 to 2003 was somewhat different, with improvement mainly observed near smaller harbours. No significant changes in imposex levels near larger harbours occurred over this period. Although the imposex levels still remain high near the large harbour complexes in Reykjavík and Hafnarfjördur, it is evident that regulations, including the use of less toxic antifouling paints and community action, have lead to substantial improvements in the marine environment of Iceland. International Maritime Organisation's ban on the application of TBT after 2003 is apparently necessary to allow further improvements in larger harbours. The environmental effects of new antifoulants replacing TBT need to be further evaluated.

Growth hormone in the male reproductive tract of the chicken: heterogeneity and changes during ontogeny and maturation

Growth hormone (GH) gene expression is not confined to pituitary somatotrophs and occurs in many extrapituitary tissues. In this study, we describe the presence of GH moieties in the chicken testis. GH-immunoreactivity (GH-IR), determined by ELISA, was found in the testis of immature and mature chickens, but at concentrations <1% of those in the pituitary gland. The immunoassayable GH concentration in the testis was unchanged between 4 and 66 weeks of age, and approximately 10-fold higher than that at 1-week of age and 25-fold higher than that in 1-day-old chicks and perinatal (embryonic day 18) embryos. This immunoreactivity was associated with several proteins of different molecular size, as in the pituitary gland, when analyzed by SDS-PAGE under reducing conditions. However, while most of the GH-IR in the pituitary ( approximately 40 and 15%, respectively) is associated with monomer (26 kDa) or dimer (52 kDa) GH moieties GH-IR in the testis is primarily (30-50%) associated with a 17 kDa moiety. GH bands between 32 and 45 kDa are also relatively more abundant in the testis than in the pituitary. During ontogeny the relative abundance of a 14 kDa GH and 40 kDa GH moieties in the testis significantly declined, whereas the relative abundance of the 17 and 45 kDa moieties increased with advancing age. In adult birds, GH-IR was widespread and intense in the seminiferous tubules. Although the GH-IR was not present in the basal compartment of Sertoli cells, nor in spermatogonia and primary spermatocytes, it was abundantly present in secondary spermatocytes and spermatids in the luminal compartments of the tubules as well as in some surrounding myocytes and interstitial cells. In summary, immunoreactive GH moieties are present in the chicken testis but at concentrations far less than in the pituitary. Age-related changes in the relative abundance of testicular GH variants may be related to local (autocrine/paracrine) actions of testicular GH. The localization of GH in spermatocytes and spermatids suggests hitherto unsuspected roles in gamete development.

Activating Transcription Factor 4 Is Required for the Differentiation of the Lamina Propria Layer of the Vas Deferens1

Activating transcription factor 4 (ATF4/CREB2) is a member of the cyclic-AMP response element-binding (CREB) family. These proteins have been shown to regulate cell proliferation and differentiation in a broad number of tissues during embryo development. Here we report that male ATF4(-/-) mice are subfertile, despite the fact that they produce sufficient sperm and are able to fertilize wild-type eggs in vitro. An analysis of the ejaculatory ducts revealed abnormal constrictions in the lumen of the vas deferens. The lamina propria layer of the vas deferens was significantly thicker in the ATF4(-/-) mice and the cells that make up this layer were rounder and more abundant than in the ATF4(+/+) littermates. The change in the morphology of the lamina propria was associated with sexual maturation. A histologic analysis of the lamina propria revealed a reduction in the production of elastic fibers and interstitial cells of Cajal, as judged by the expression of neuron-specific enolase. These observations predict that ATF4 is required for the normal differentiation of the lamina propria layer of the vas deferens at sexual maturation. The morphology of the ATF4(-/-) lamina propria and the constriction of the lumen are consistent with an obstruction in the vas deferens contributing to the subfertility of the ATF4(-/-) males.

Induction of reproductive tract developmental abnormalities in the male rat by lowering androgen production or action in combination with a low dose of diethylstilbestrol: evidence for importance of the androgen-estrogen balance

This study tested the hypothesis that testis/reproductive tract abnormalities induced in the rat by neonatal treatment with diethylstilbestrol (DES) result from disturbance of the androgen-estrogen balance. Male rats were treated neonatally with a dose of DES (0.1 micro g) that induced either no or small effects on its own or with a dose (10 micro g) that induced major reproductive tract abnormalities. To allow quantification, the abnormalities chosen for study were distension of the rete testis and efferent ducts and reduction in epithelial cell height in the efferent ducts and vas deferens. To alter the androgen-estrogen balance, other rats were treated with DES (0.1 micro g) in combination with a treatment to suppress either androgen production [GnRH antagonist (GnRHa)] or androgen action (flutamide); other rats were treated with GnRHa or flutamide alone. Testosterone levels were measured to verify the effects of treatment. Combined administration of DES (0.1 micro g) plus GnRHa or flutamide induced significantly greater distension/overgrowth of the rete testis and efferent ducts (ED) and a reduction in epithelial cell height of the ED than did DES (0.1 micro g) administered alone. Neither GnRHa nor flutamide affected rete or ED distension when administered alone, but both significantly reduced ED epithelial cell height. Neonatal treatment with bisphenol-A (100 micro g) with or without GnRHa had no significant effect on any of these parameters. In contrast to the ED, a reduction in cell height of the vas deferens was induced to an equal extent by DES (10 micro g), DES (0.1 micro g) with GnRHa, and GnRHa alone, suggesting greater sensitivity of this tissue to both androgen and estrogen action. The induction of major abnormalities in rats treated with DES (10 micro g) was coincident with loss of androgen receptor immunoexpression in affected tissues. Reduced androgen receptor immunoexpression was also induced by combined treatment with DES (0.1 micro g) plus GnRHa or flutamide, whereas treatment with any of these compounds alone had no or only minor effects. These findings suggest that reduced androgen action sensitizes the reproductive tract to estrogens, demonstrating that the balance in action between androgens and estrogens, rather than their absolute levels, may be of fundamental importance in determining normal or abnormal development of some regions of the male reproductive tract.

Maturational and maintenance effects of testosterone on terminal axon density and neuropeptide expression in the rat vas deferens

Testosterone causes growth of many pelvic ganglion cells at puberty and their maintenance during adulthood. Here we have focused on two populations of pelvic ganglion cells that project to the rat vas deferens: noradrenergic neurons that innervate the smooth muscle and synthesize neuropeptide Y, and cholinergic neurons that primarily innervate the mucosa and contain vasoactive intestinal peptide. We have assessed the muscle innervation after pre- or postpubertal castration, using immunohistochemistry to determine axon density and radioimmunoassay to quantify levels of neuropeptides in tissue extracts. Our results show that androgen deprivation in each period causes substantial effects. Noradrenergic axons in the muscle increase in density after castration, partly due to organ size being smaller than age-matched controls. However, when corrected for target size, there is an overall decrease in total number of axons. This implies that androgen exposure at puberty has a direct effect on neurons to ensure that the adult pattern of innervation is attained, and that this is not simply by matching terminal field to target size. Similar effects of pre- and postpubertal castration imply that continued exposure to testosterone is necessary to maintain normal target innervation. Castration in both time periods increased the density of axons containing vasoactive intestinal peptide, however the effects of castration on the total number of these axons in the muscle were more variable. The concentration of vasoactive intestinal peptide increased substantially following either pre- or postpubertal castration although absolute amounts per vas deferens were decreased. Effects on neuropeptide Y concentration were less pronounced but the total amount per vas deferens was decreased after pre- or postpubertal castration. Our study shows that the action of testosterone (or a metabolite) on a pelvic ganglion cell soma is likely to reflect a change in its terminal field, but that these effects are not mediated simply by testosterone influencing the size of its target organ.

Imposex and tributyltin contamination as a consequence of the establishment of a marina, and increasing yachting activities at Phuket Island, Thailand

The objective was to investigate how tributyltin (TBT) contamination resulting from the establishment of a new marina and increasing yachting activities at Phuket Island, Thailand affects the area. A minimum of 30 specimen of the mangrove dwelling muricid Chicoreus capucinus were collected at five stations 2 months before and 5, 9, 18 and 33 months after Yacht Haven Marina was constructed. Imposex measured as RPLI and VDSI were significantly correlated to duration of time after construction and distance from the marina. All females developed imposex close to the marina after 18 months, whereas no significant increase occurred at stations more than 2 km from the marina. To evaluate the range of effects of the increasing yachting activities the muricid Thais distinguenda was used as an indicator of imposex at two popular mooring sites for yachts at Phi Phi and Raja Island in Phangna Bay, Thailand. The incidence of imposex was 100% at stations close to the mooring sites. A significant correlation existed between the distance from the sites and the incidence of imposex. The increasing incidence of imposex suggest that TBT contamination is worsening, against global trends, because regulations prohibiting the use of TBT-based paints, do not exist in Thailand.

Spatial distribution and developmental appearance of postjunctional P2X1 receptors on smooth muscle cells of the mouse vas deferens

P2X1-type purinoceptors have been shown to mediate fast transmission between sympathetic varicosities and smooth muscle cells in the mouse vas deferens but the spatial organization of these receptors on the smooth muscle cells remains inconclusive. Voltage clamp techniques were used to estimate the amplitudes of spontaneous excitatory junction currents (SEJCs) in cells of the vas deferens longitudinal smooth muscle layer. These currents involved the activation of about 6% of the P2X-type channels present on the cell, as compared to whole cell currents produced when isolated smooth muscle cells were exposed to maximal concentrations of either ATP or alpha,beta-MeATP. Immunofluorescence staining of the vas deferens with antibodies against P2X1 receptor showed a diffuse, grainy distribution over the entire membrane of each smooth muscle cell. Anti-P2X1 staining was not markedly clustered beneath anti-SV2-stained sympathetic varicosities. Similar results were obtained for cells in the urinary bladder. During development, P2X1 mRNA was detected as early as embryonic day 15 (E15). Increasing intensities of diffuse immunostaining for P2X1 were observed in the walls of the bladder, tail artery, and aorta from E15 until 6 weeks postnatal. The vas deferens showed increasing intensities of diffuse staining of its smooth muscle layers between 2 and 6 weeks postnatal, consistent with the time-course of development of fast purinergic transmission described previously. Together, the results suggest that the response of smooth muscle of the vas deferens to ATP released from sympathetic varicosities relies on rapidly desensitizing P2X1 receptors, distributed diffusely across the smooth muscle cell surface.

Age-, cell- and region-specific immunoexpression of estrogen receptor alpha (but not estrogen receptor beta) during postnatal development of the epididymis and vas deferens of the rat and disruption of this pattern by neonatal treatment with diethylstilbestrol

This study in rats sought to 1) characterize immunoexpression of estrogen receptor alpha (ERalpha) and ERss in the efferent ducts, epididymis, and vas deferens during postnatal development; 2) establish whether ER expression changed after neonatal treatment with diethylstilbestrol (DES); and 3) determine whether ER changes coincided with abnormal epididymal/vas development. Rats were administered 10 microg DES or vehicle on days 2, 4, 6, 8, 10, and 12 and were sampled on days 10, 18, 25, 35, and 90+. At all ages, ERalpha was immunoexpressed intensely in the efferent ducts. On day 10, immunoexpression of ERalpha was absent from the epididymis and vas, but was detectable on day 18 in epithelial cells in the caput, corpus, and proximal cauda. Epithelial expression of ERalpha was absent from the distal cauda and in the proximal and distal vas was confined to a band of periductal stromal cells. Thus, on day 18, the site of ERalpha expression delineated the epididymis-vas boundary. On days 25-35, epithelial expression of ERalpha was absent, but stromal expression persisted in the vas and distal cauda. In adults, immunoexpression of ERalpha in the epididymis and vas was absent. In contrast, ERbeta was immunoexpressed in epithelial cells and some stromal cells in the efferent ducts, epididymis, and vas at all ages. In the vas, stromal expression of ERalpha and ERbeta was in different layers. DES treatment caused 1) underdevelopment of the epididymal duct and reduced epithelial height in epididymis and vas; 2) coiling of the extraepididymal vas; 3) thickening of the periductal actin-free stromal layer in the distal cauda and vas; and 4) reduced cell proliferation on day 18 in the epididymis and vas, based on incorporation of bromodeoxyuridine, especially in the epithelium. These changes coincided with abnormalities in cell- and region-specific immunoexpression of ERalpha, but not ERbeta. Thus, in DES-treated rats on day 18, epithelial expression of ERalpha occurred in all regions of the epididymis and vas instead of being confined to the caput, corpus, and proximal cauda as in controls. Similarly, stromal ERalpha expression in the vas of DES-treated rats was not confined to a periductal layer as in controls, but occurred diffusely in the muscle layer. It is suggested that 1) estrogens play a role in peripubertal development of the epididymis and vas; 2) the cellular site of expression of ERalpha either plays a role in or reflects demarcation of the epididymal/vas boundary; and 3) blurring of this boundary in DES-treated rats coincides with altered ERalpha immunoexpression.

Morphological changes in the vas deferens and expression of the cystic fibrosis transmembrane conductance regulator (CFTR) in control, deltaF508 and knock-out CFTR mice during postnatal life

The morphology of the mouse vas deferens still undergoes major changes from birth to 40 days of age, such as differentiation of the mesenchymal cells into fibroblasts and muscle cells, differentiation of the epithelium into basal and columnar epithelial cells, development of stereocilia, and the appearance of smooth endoplasmic reticulum organised in fingerprint-like structures or parallel, flattened saccules. In mutant homozygous DeltaF508 (DeltaF/DeltaF) and knock-out (cf/cf) CFTR mice, strain 129/FvB and 129/C57BL-6, respectively, a similar development occurred until the age of 20 days. At 40 days, however, the lumen was filled with eosinophilic secretions, and sperm cells were absent in the majority of the animals examined, although sperm production in testis and epididymis appeared to be normal. CFTR was localised in the apical membrane and cytoplasm of the vas deferens epithelium from 40 days on but could not be detected in the vas deferens before 20 days or in mutant adult CFTR mice as expected. Western blots of membrane preparations showed that the mature form of CFTR was present in vas deferens and testis but absent in seminal vesicles. Our results suggest that the function of CFTR is probably essential after 20 days in the vas deferens and that its absence or dysfunction may result in a vas deferens with a differentiated epithelium but a collapsed lumen, which could at least temporarily delay the transport of spermatozoa. These observations contrast with those made in the overall majority of CF patients. Mol. Reprod. Dev. 55:125-135, 2000.

Development of the genital ducts and spermathecae in the Rhyacodrilines rhyacodrilus coccineus and Monopylephorus rubroniveus (Oligochaeta, tubificidae)

The male genital duct in Tubificidae consists of a funnel, a vas deferens, an atrium, and, frequently, a copulatory structure. There may also be a diffuse or compact prostate gland in association with the duct. The morphogenesis of this duct is described for Rhyacodrilus coccineus and Monopylephorus rubroniveus (Rhyacodrilinae). The funnel and vas deferens in both species originate from peritoneal (mesodermal) cells in the posterior septum in the testis segment. The atrium in R. coccineus develops from a primary epidermal (ectodermal) invagination. A typical atrium is not formed in M. rubroniveus; the entire duct is of mesodermal origin. In the latter species, a shallow epidermal invagination occurs, into which both male ducts open, but it bears resemblance to a copulatory structure, which usually forms from a secondary invagination, rather than to a proper atrium. We therefore conclude that M. rubroniveus lacks an atrium. The copulatory structure is termed the male bursa. Both species have diffuse prostate glands that differentiate from peritoneal (mesodermal) cells surrounding the male duct. In R. coccineus the cells cover the atrium, whereas in M. rubroniveus they cover only a part of the vas deferens. The development of the spermathecae and female ducts is also examined. The spermatheca is of ectodermal origin in both studied species, i.e., it forms as an invagination of the epidermis. The female duct develops from peritoneal (mesodermal) cells in the posterior septum of the ovary segment. However, in M. rubroniveus the first sign of the duct disappears and a proper duct never develops.

Perinatal fenvalerate exposure: behavioral and endocrinology changes in male rats

The effects of maternal exposure to fenvalerate during the prenatal and postnatal periods of sexual brain differentiation were studied in adult male offspring. Behavioral (open field, stereotyped, and sexual behaviors), physical (sexual maturation, body and organ weights), endocrine (testosterone levels), and neurochemical (striatal and hypothalamic monoamine and respective metabolite levels) data were assessed. The results showed that there was no change in the age of testis descent or testis weight, nor were there changes in monoamine levels or stereotyped behavior. However, there were significant reductions in ductus deferens and seminal vesicle weights and plasma testosterone concentrations. In addition, treated offspring showed decreased male sexual behavior and increased immobility in the open field. These results indicate that perinatal exposure to fenvalerate during the critical periods of male brain sexual differentiation has long-term effects on the reproductive physiology and behavior of male rats.

Spontaneous occurrence of vasculitis-like lesions in male reproductive tissues in mice: a histological study

Vasculitis involving testes, epididymides, and vasa deferentia is considered to be a rare disease but has often been reported in man. In the present study, reproductive tissues of young and aged mice were examined to determine whether spontaneous vasculitis occurs in them. Testes, ductuli efferentes, epididymides, and vasa deferentia were obtained from young and aged BALB/c mice together with some nonreproductive organs for histological observation at the light microscopic level. The examination revealed that vasculitis-like lesions comparable to those in man were significantly present in the epididymides and vasa deferentia of aged but not young mice. However, no significant lesions were found in the testes and ductuli efferentes. Furthermore, other organs, such as salivary glands, thyroid glands, livers, pancreases, and kidneys, were also negative for the lesions. These results indicate that the epididymis and vas deferens are spontaneously apt to be affected by vasculitis-like lesions with advancing age, but that the lesions are not due to a systemic vasculitis disease.

Postnatal differentiation of the ductus deferens, tail of the epididymis, and distal body of the epididymis in goats occurs independently of rete testis fluid

Observations from extratesticular rete-ligated, mature goats indicated that epithelial morphology in the tail of the epididymis can be maintained without any input from testicular fluid (Goyal et al., Acta Anat., 1994;150: 127-135). Hence, the objective of this study was to determine whether the tail of the epididymis and/or other regions of the male excurrent ducts can differentiate prior to the appearance of lumen in the seminiferous tubules, which is an indicator for the onset of seminiferous tubular fluid secretion. Based on age and scrotal circumference (SC), 20 male goats were divided into four groups of five animals each: 1-4 weeks (SC, 6.5-7.5 cm), 7-10 weeks (SC, 8.5-11.0 cm), 12-15 weeks (SC, 11.0-14.0 cm), and 15-25 weeks (SC, 16.0-19.0 cm). Tissues were collected from the testis, six regions of the epididymis (proximal, middle and distal head; proximal and distal body; and tail), and the ductus deferens, and were processed for light and electron microscopic examination. Changes in epithelial height and cytological features associated with absorption (microvilli, pinocytotic and coated vesicles) and protein secretion (RER, Golgi body) were used as markers for differentiation. Differentiation of all of these features was comparable to that observed in the 15-25-week-old animals in the ductus deferens by > or = 1 week, in the tail of the epididymis by > or = 7 weeks, in the distal body of the epididymis by > or = 12 weeks, and in the proximal body of the epididymis and all three regions of the head of the epididymis by > or = 15 weeks. Seminiferous tubules developed lumens between 12 and 15 weeks. In conclusion, epithelial differentiation in the ductus deferens, tail of the epididymis, and distal body of the epididymis follows a time-dependent, spatial, ascending order and is achieved before lumen formation in the seminiferous tubules. Conversely, epithelial differentiation in all three regions of the head and the proximal body of the epididymis occurs simultaneously and after lumen formation in the seminiferous tubules.

GPx3: the plasma-type glutathione peroxidase is expressed under androgenic control in the mouse epididymis and vas deferens

We report here-using northern experiments, western blotting, and immunohistochemistry-on the findings that the plasma type glutathione peroxidase, GPx3, a major enzyme in reducing lipid hydroperoxides and hydrogen peroxide in plasma, is also expressed at significant levels in tissues of the male genital tract including epididymis and vas deferens. Within the epididymis and the kidney, the accumulation of the GPx3 mRNA and protein were investigated during postnatal development and found to be temporally regulated in a tissue-specific manner. Furthermore, we show here that androgen withdrawal by castration down regulates the expression of the GPx3 gene both in the epididymis and vas deferens while GPx3 expression in the kidney was found to be androgen-independent. Finally, immunohistochemistry data reveals that within the epididymis GPx3 distribution is quite peculiar suggesting the existence in this organ of complex traductional and/or transcriptional regulatory processes.

Structure and autonomic innervation of the human vas deferens: a review

The motor innervation of the smooth muscle coat of the human vas deferens is predominantly noradrenergic in type while a less dense and differently distributed presumptive cholinergic innervation is also in evidence, although the precise role of the latter is undetermined. Immunohistochemical studies have confirmed the presence of catecholamine-synthesizing enzymes tyrosine hydroxylase (TH) and dopamine beta hydroxylase (DbetaH) in the majority of fine, varicose intramuscular nerves, about two-thirds of which also contain neuropeptide Y (NPY). Minor populations of noradrenergic nerves contain enkephalin (ENK), galanin (GAL), somatostatin (SOM), or nitric oxide synthase (NOS). The presumptive cholinergic intramuscular nerves contain vasoactive intestinal polypeptide (VIP) and NPY. The subepithelial nerves of the vas deferens are assumed to have a secretomotor function and are rich in acetylcholinesterase and NPY, many also containing either VIP or NOS. The muscle coat of the human vas deferens is poorly differentiated until after birth, the intramuscular nerves in the fetus being relatively thick and non-varicose. Development of a subepithelial nerve plexus lags behind that in the muscle coat but its density in the neonatal vas deferens resembles that seen in the adult. Observations on specimens of human vas deferens obtained at vasovasostomy carried out 1 to 15 years after vasectomy have shown a marked reduction in the density of noradrenergic nerves in the muscle coat of the testicular portion while that in the urethral portion remains unaltered. Furthermore, the subepithelial secretomotor nerves degenerate in the testicular portion. These long-term changes in the pattern of innervation of the vas deferens consequent upon vasectomy may have profound effects upon the outcome of vasovasostomy with respect to subsequent sperm maturation, transport, and viability.

Immunolocalization of androgen receptor and estrogen receptor in the developing testis and excurrent ducts of goats

BACKGROUND

Because of the significance of androgens and estrogens in prenatal and postanatal differentiation of the testis and excurrent ducts, it is important to understand the developmental pattern of androgen receptor (AR) and estrogen receptor (ER) in these organs.

METHODS

Tissues from 1-23-week-old goats were fixed in 4% paraformaldehyde and embedded in Paraplast-plus. Antigenic sites for AR and ER were immunolocalized using the PG-21 rabbit anti-rat/human antibody and the H-222 rat anti-human monoclonal antibody, respectively. The avidin-biotin horseradish peroxidase procedure was used to identify positive immunoreactivity. Controls included incubation of sections with irrelevant IgG in place of primary antibody.

RESULTS

Within the testis, immunostaining for AR in the nuclei of Sertoli cells increased gradually from mild at week 1 to strong at week > or = 19. In contrast, nuclei of peritubular myoid cells and Leydig cells exhibited moderate to strong reaction for AR in all animals. Germ cells were negative. Within the rete testis, efferent ductules, regions I-V of the epididymis, and ductus deferens, nuclei of all epithelial cells, peritubular myoid cells, and intertubular connective tissue cells expressed moderate to strong staining for AR at all ages. ER were confined to nonciliated cells of the efferent ductules, which displayed moderate staining in all animals, beginning from week 1.

CONCLUSIONS

Nuclear AR staining, found in all testicular cells (except germ cells) and excurrent duct cells examined, was observed to change in an age-related manner only in Sertoli cells, where staining intensity increased between week 1 and week 19. Staining for ER, confined to nonciliated epithelial cells of the efferent ductules, was not affected by postnatal age.

Immunohistochemical characteristics of nerve fibres supplying the porcine vas deferens. A colocalisation study

Double-labelling immunofluorescence was used to investigate the coexistence of the catecholamine-synthesising enzymes, tyrosine hydroxylase and dopamine-beta-hydroxylase and several neuropeptides including neuropeptide Y, vasoactive intestinal polypeptide, Leu5-enkephalin, somatostatin, calcitonin gene-related peptide and substance P in nerve fibres supplying the vas deferens in juvenile and adult pigs. The study has revealed three major populations of nerve terminals innervating the organ: (1) noradrenergic fibres; (2) non-noradrenergic (putative cholinergic) fibres containing vasoactive intestinal polypeptide, neuropeptide Y and somatostatin, supplying almost exclusively the lamina propria; and (3) non-noradrenergic, presumably sensory fibres, containing calcitonin gene-related peptide and substance P. The population of noradrenergic nerves can be divided into three subpopulations: a somatostatin-containing, a Leu5-enkephalin-containing and a subpopulation immunonegative to the peptides investigated, in descending order of magnitude. Coexistence patterns of the substances existing within nerve fibres supplying the vas deferens blood vessels are clearly different from those found in nerve fibres innervating the organ wall. The majority of the noradrenergic fibres associated with blood vessels contain neuropeptide Y only, while non-noradrenergic perivascular nerves contain predominantly vasoactive intestinal polypeptide. The possibility of different sources of origin of the particular nerve fibre subpopulations supplying the porcine vas deferens and its blood vessels is discussed.

Postnatal development of delta-opioid receptor subtypes in mice

1. The density and affinity of binding sites for the delta-selective opioid ligands [3H]-[D-Ala2, Asp4]deltorphin (DELT-I), [3H]-[D-Ala2Glu4]-deltorphin (DELT-II), [3H]-[D-Pen2,D-Pen5]enkephalin (DPDPE), and [3H]-naltrindole (NTI) were determined in whole brain from 10, 15, 25 and 60 day-old C57BL mice. 2. At all ages, the analyses of the homologous displacement curves, gave best fits to single rather than to multiple site models. The binding capacity (Bmax) labelled by [3H]-NTI was about one half that labelled by [3H]-DELT-I, [3H]-DELT-II and [3H]-DPDPE. In 25 and 60 day-old mouse brain the DPDPE Bmax was 25% less than the deltorphin-II Bmax. 3. In saturation experiments, specific binding of [3H]-DELT-I on adult mouse brain homogenates was best fitted by a two-site model (34%, high affinity site, Kd = 1.08 nM and 66% low affinity sites, Kd = 39.9 nM). 4. DPDPE produced a biphasic inhibition of specific [3H]-DELTI-I binding, from 15 days of age onwards. The relative percentage of high and low affinity sites was 72% and 28% in 15 day-, 65% and 35% in 25 day- and 30% and 70% in 60 day-old mice. 5. In adult mouse brain labelled with [3H]-DELT-I, DELT-II recognized 71% of high-affinity and 29% of low-affinity sites DELT-I and DPDPE produced monophasic inhibition of specific [3H]-DELT-II binding to brain homogenates of adult mice. 6. These data suggest that a sub-population of delta-sites (probably the delta 2-subtype), recognized by DELT-I, with high affinity for DELT-II and low affinity for DPDPE develops from 25 days onward. 7. In electrically stimulated mouse vas deferens (MVD) the rank order of potency of the three delta-agonists was: DELT-I > DELT-II > DPDPE in 10 day-old mice: and DELT-I- DELT-II > DPDPE, from 25 days onward. During this time, the potency of DELT-II increased about 15 fold whereas the potency of DELT-I and DPDPE increased only 5 times. The higher efficacy of DELT-II could depend on receptor maturation towards the delta 2-subtype.

Freeze-fracture study of cell junctions in the epididymis and vas deferens of a seasonal breeder: the mink (Mustela vison)

The present study used the freeze-fracture technique and vascular infusion of horseradish peroxidase (HRP) as a junction permeability tracer, visible in thin sections, to investigate potential seasonal variations in the mink epididymis and vas deferens cell junctions. The junctions were studied in kits during the neonatal period, during and after puberty, and during adulthood monthly throughout the annual reproductive cycle. Results showed the existence, at the time of birth, of a junctional complex joining ductal cells that reached the lumen of the epididymis and vas deferens. The lumenal impermeable segment of the junctional complex was characterized by the presence of an occluding zonule made up of continuous tight junctional ridges extending around the perimeter of the cell. The basal permeable segment of the junctional complex contained mainly discontinuous ridges with frequent forming gap and tight junctions next to adhering junctions. Receding annular junctions were present in the apical and lateral cytoplasm of principal and clear cells. The membrane domain apical to the occluding zonule bore 30-35 nm exo/endocytosis blebs and 40-60 crenations associated with deforming tight and gap junctions made up of randomly scattered particles. Patterns of junctional strands varied greatly from one principal and/or clear cell to another. However, cell junctions did not significantly vary from the neonatal period to adulthood nor from breeding to testicular regression. Anatomical subdivisions of the epididymis with fewer junctional strands per zonule and high diversity in their patterns exhibit no permeability differences to HRP when compared with subdivisions containing more numerous strands. The junctions were impermeable during the neonatal period and throughout the annual reproductive cycle. The following conclusions were reached: 1) a competent occluding zonule developed in the mink epididymis and vas deferens before it did in the testis; 2) the number of strands and the diversity of patterns did not correlate with permeability differences; 3) after the development of a lumen in the testicular excurrent duct, neither receding cellular changes caused by testicular regression nor seasonal passage of a bolus of sperm through the duct modified the occluding zonules; and 4) in the testicular excurrent duct, junction modulation (i.e., formation and deformation) paralleled that in the testis and followed the direction of the synthesis-transport-secretion process.

Developmental changes in methylation of spermatogenesis-specific genes include reprogramming in the epididymis

We have determined the status of DNA methylation at specific sites in three spermatogenesis-specific genes, Pgk-2, ApoA1 and Oct-3/4, throughout the development and differentiation of male germ cells in the mouse. We observed a specific demethylation event in the Pgk-2 gene in prospermatogonia at about the time of birth, about 10 days before the onset of transcription which first occurs in primary spermatocytes. All three genes were unmethylated in adult spermatogenic cells in the testis, but were remethylated in mature spermatozoa in the vas deferens. Surprisingly, we found that this remethylation is part of the process of sperm maturation which occurs in the epididymis.

Characterization and ontogeny of P1-purinoceptors on rat vas deferens

1. The P1-purinoceptors which mediate the inhibition by adenosine of nerve-mediated contraction of the rat vas deferens have been investigated by use of the agonists N6-cyclopentyladenosine (CPA) and 5'-N-ethylcarboxamidoadenosine (NECA) and the A1-selective antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX). The ontogeny of the responses to adenosine and to the two co-transmitters which induce the contractions in this tissue, adenosine 5'-triphosphate (ATP) and noradrenaline (NA), have also been studied. 2. The order of potency for the adenosine agonists in inhibiting the nerve-mediated contractions was CPA = NECA > adenosine. Micromolar concentrations of DPCPX were required to antagonize the inhibition by adenosine and NECA of nerve-mediated responses, whereas the inhibitory effect of CPA was antagonized by nanomolar concentrations of the antagonist. 3. NECA and adenosine inhibited contractions induced by ATP (10 microM) or by NA (10 microM), NECA being at least ten fold more potent than adenosine, whereas CPA was inactive. Micromolar concentrations of DPCPX were required to antagonize the effect of adenosine on the contractions induced by ATP (10 microM). 4. Nerve-stimulated contractions could be observed in neonatal tissues from day 15 and increased with age, and could be inhibited by adenosine from this time, the potency of adenosine decreasing with age. Responses to ATP also appeared at day 15 and increased with age up to day 25, while responses to NA were present from day 10 (the earliest day tested) and decreased with age. 5. These results show that the rat vas deferens contains both prejunctional Al-receptors and postjunctional A2-receptors, and that adenosine acts on the latter populations to inhibit nerve-mediated contractions.The high potency of adenosine in the neonate and the parallel development of responses to ATP and to nerve-mediated contractions support suggestions that purinergic responses may be particularly important in neonatal tissues.

Histophysiological and morphometric studies of the post-natal development of rat vas deferens

The post-natal growth and differentiation of the vas deferens was studied in rats aged 1-180 d by light, and with transmission electron microscopy in parallel with a radioimmunoassay of serum testosterone. During the first week and the major part of the second week of the post-natal life the vas deferens presented embryological features. Differentiation of the proximal and distal segments of the vas started 12 d after birth. At 25 d, the epithelium of the mucosa in the distal segment already showed some adult histologic characteristics. The weight notably increased between 1 and 45 d and the higher rates of growth of their histologic components occurred until 45 or 60 d, in parallel to testosterone serum levels. These results suggest that growth and differentiation of the vas deferens are androgen-dependent events and precede the end of the first spermatogenic cycle, assuring the viability of spermatozoa that will enter the duct.

Comparison of the effects of the 5 alpha-reductase inhibitor finasteride and the antiandrogen flutamide on prostate and genital differentiation: dose-response studies

Studies were performed to compare the effects of 5 alpha-reductase inhibition and antiandrogen receptor blockade on differentiation of male internal and external genital structures and prostate in the rat. Dose-response studies were performed on male rats treated in utero during the period of sexual differentiation with either the potent 5 alpha-reductase inhibitor finasteride or the antiandrogen flutamide. The treated animals were raised to adulthood and killed, and genital structures were evaluated. Treatment with the 5 alpha-reductase inhibitor finasteride at a dose of 25 mg/kg.day resulted in significant feminization of the external genitalia. There was no further feminization of the genitalia at doses up to 300 mg/kg.day. Wolffian ductal differentiation occurred at all doses evaluated. Seminal vesicle weight, however, significantly decreased at 25 mg/kg.day, but without a further decrease at higher doses of the 5 alpha-reductase inhibitor. Vas deferens and epididymal weights were unchanged at all doses evaluated. There was a significant decrease in prostate size at 25 and 50 mg/kg.day, with no further decrease at higher doses. In flutamide-treated animals, complete feminization of the genitalia occurred at 24 mg/kg.day in all animals. At 18 mg/kg.day, Wolffian ductal differentiation occurred, but seminal vesicle weight was decreased. At dosages of 100, 200, and 300 mg/kg.day flutamide, the vas deferens was absent unilaterally or bilaterally, with small remnants of epididymal head and tail present. At dosages of 24 mg/kg.day and above, the prostate was absent. Studies with the 5 alpha-reductase inhibitor finasteride demonstrate the dependency of prostate and male external genital differentiation on dihydrotestosterone (DHT). However, unlike androgen receptor blockade with flutamide, finasteride did not totally abolish prostate differentiation or completely feminize the external genitalia, despite increasingly higher doses. Since there is no evidence of multiple 5 alpha-reductase isoenzymes to date in the rat, these results suggest that testosterone (T) can compensate for DHT to some degree at the level of the androgen receptor. Wolffian differentiation, however, was not affected by inhibition of DHT, demonstrating its T dependency, but seminal vesicle growth was impaired. Thus, inhibition of 5 alpha-reductase activity limits seminal growth potential in adulthood. Studies with the antiandrogen flutamide show that at doses significantly above that required to completely block prostate differentiation and cause genital feminization, Wolffian ductal differentiation is significantly impaired. Thus, higher doses of flutamide are needed to block the paracrine effect of T on the Wolffian ducts.

Injury to the pre-pubertal vas deferens. I. Histological analysis of pre-pubertal human vas

There is very little information in the literature on the development of the human vas deferens. Therefore, the age at which the pre- or para-pubertal vas deferens becomes large enough for a vasovasostomy to be technically feasible is unknown. To determine the age or degree of sexual maturity at which a microscopic vasovasostomy is technically feasible, we collected surgical or autopsy vasa from 34 young males over a three year period, and correlated vasal size to age and Tanner stage (degree of sexual maturity ranging from 1-childhood to 5-adult). The specimens were embedded and sectioned transversely in glycol methacrylate. Using image analysis, the total transverse area and diameter, and luminal area and diameter was determined for each specimen. Surprisingly, there was no change in vasal size from birth up through 11 years. From age 15 years and on, the vas was adult in size. The vas develops to adult size between Tanner stages 2 and 3. The average external and luminal diameters of pre-midpuberty specimens (Tanner stages 1 and 2) were 1.0 and 0.19 (mm.) and the diameters of post-midpuberty specimens were 2.1 and 0.43 (mm.), respectively. These results suggest that, in the event of a recognized iatrogenic injury to the vas deferens after midpuberty, a repair by a traditional microsurgical vasovasostomy is possible. If the vas is injured before midpuberty it may be technically difficult to repair by traditional microsurgical methods.

Developmental and hormonal regulation of specific proteins in mouse vas deferens and seminal vesicle

This paper is concerned with hormonal regulation of the developmental pattern of major proteins of the mouse vas deferens (mouse vas deferens protein: MVDP, 34.5 kD) and seminal vesicle (15.5, 120 and 140 kD) whose expression is regulated by testosterone at adulthood. The ontogeny of these proteins, studied by SDS-polyacrylamide gel electrophoresis, appeared to be uncoordinated. MVDP was not accumulated until animals were 20 days old and its concentration increased sharply from 20 to 30 days of age. In seminal vesicle, the 15.5 kD protein did not accumulate before day 30 whereas 120 and 140 kD proteins appeared and accumulated between 30 and 40 days. In 30-day-old mice castrated at birth or treated with cyproterone acetate over 29 days, MVDP levels were not abolished and were similar to those measured in 20-day-old males. Testosterone administration, from 1 to 10 days of age, did not induce precocious expression of MVDP. These results suggest that the neonatal expression of MVDP is independent of androgens. In seminal vesicle, the first expression of the 3 proteins studied was dependent upon testicular androgens as shown by neonatal castration and injection experiments. The marked increase in the levels of the 4 proteins studied, during sexual maturation, was not associated with quantitative or qualitative changes in tissular androgen concentrations, suggesting that other factors may be necessary for protein expression. Whereas thyroxine may induce a precocious accumulation of MVDP, prolactin had no stimulatory effect on the accumulation of proteins from vas deferens and seminal vesicle. The results suggest that during sexual maturation gene activation by androgens was progressive.

Androgen dependence during development of the mouse vas deferens protein mRNA

The mRNA encoding a major protein of the mouse vas deferens (MVDP) was first detected in 10-day-old males and its concentration increased sharply between 10 and 20 days, reaching adult levels at 40 days. This increase was not associated with an increase in tissular androgen concentrations. In 30-day-old mice castrated at birth or treated with cyproterone acetate over 29 days, MVDP mRNA levels were not abolished and were similar to those measured in 10- and 20-day-old controls. These results suggest that the neonatal expression of MVDP gene is independent of androgens. In addition, precocious accumulation of MVDP mRNA could be induced by injection of excess amounts of androgens in 20- but not in 10-day-old animals. The prepubertal increase in MVDP mRNA levels is androgen-dependent but other factors may be necessary for MVDP expression.

Neonatal seminal vesicle mesenchyme induces a new morphological and functional phenotype in the epithelia of adult ureter and ductus deferens

Mesenchyme from neonatal mouse and rat seminal vesicles (SVM) was grown in association with postnatal (adult) epithelial cells from the ureter (URE) and ductus deferens (DDE) in chimeric tissue recombinants composed of mouse mesenchyme and rat epithelium or vice versa. Functional cytodifferentiation was examined in these SVM + URE and SVM + DDE tissue recombinants with antibodies against major androgen-dependent seminal-vesicle-specific secretory proteins. Adult DDE and URE were induced to express seminal cytodifferentiation and produced the complete spectrum of major seminal vesicle secretory (SVS) proteins. The SVS proteins produced were specific for the species that provided the epithelium. In the case of SVM + URE recombinants, the URE, which normally lacks androgen receptors (AR), expressed AR. These results demonstrate that adult epithelial cells retain a developmental plasticity equivalent to their undifferentiated fetal counterparts and are capable of being reprogrammed to express a completely new morphological, biochemical and functional phenotype.

Neonatal exposure to oestrogens alters the protein profiles and gene expression in the genital tract of adult male mice

After neonatal administration of supraphysiological doses of oestradiol, the concentration of tissue proteins, in adult mice, was significantly reduced by 39, 45 and 56% in epididymis, vas deferens and seminal vesicle respectively. The protein profiles showed persistent alterations. In epididymis, 4 protein bands were differentially increased (14.4, 43 and 67 kDa) or reduced (24 kDa) in oestrogenized males. In vas deferens, 4 proteins were increased (14.4, 49,67 and 76 kDa) and one (34 kDa) virtually absent. In seminal vesicle, about 20 proteins of varying molecular weights (12-140 kDa) were differentially increased or decreased. Testosterone substitution, at adulthood, was unable to reverse these effects. Treatments with oestradiol during adult life induced persistent alterations in the protein profiles of the 3 organs but, in contrast to neonatal treatment, these alterations could be reversed by androgen therapy. A cDNA library has been constructed with RNA prepared from adult seminal vesicle and screened by differential hybridization. Neonatal oestrogenization strongly reduced the abundance of some mRNA species. Eleven recombinants containing putative oestrogen-sensitive sequences were isolated. Two of them, having an insert of about 500 base pairs, were used for dot-blot hybridization. Results showed that the two clones contained sequences which were differently regulated by androgens.

Inhibitory effects of technical grade methoxychlor on development of neonatal male mouse reproductive organs

Effects of technical grade methoxychlor (MX), an estrogenic insecticide, and 17 beta-estradiol (E2) were examined on serum testosterone (T) concentrations and growth and histology of neonatal male mouse reproductive organs. Male NIH/Swiss mice received i.p. injections daily from birth to Day 9 with one of the following: 10 micrograms E2 or 0.1 or 1.0 mg MX or sesame oil vehicle. The mice were killed on Day 10. MX or did not affect body weights or mortality. Serum T concentrations in control mice were 0.29 +/- 0.03 ng/ml; T concentrations in males treated with MX or E2 were reduced. The 1.0-mg dose of both MX and E2 significantly decreased DNA contents of the seminal vesicles (SV), bulbourethral glands (BUG), and ventral prostate (VP) compared to controls. In the same animals, DNA contents of testes, epididymides, and efferent ductules were not decreased. The lower dose of MX (0.1 mg) decreased DNA content of only BUG and SV. DNA content of the ductus deferens was not affected by any treatment. E2 and both doses of MX also decreased epithelial morphogenesis in the SV and BUG, and inhibited the onset of mucin production in BUG epithelium and smooth muscle differentiation in the ductus deferens. In summary, our results indicate that technical grade MX, at doses as low as 0.1 mg/day, and E2 inhibit neonatal male reproductive tract development and decrease serum T concentrations.

The effect of non-union of testis and epididymis and of cryptorchidism on the development of epididymis and ductus deferens in the rat

16-days old rats were operated with either uni- or bilateral ligation of ductuli efferents and separation of testis and epididymis to the level of the inferior epididymal artery (non-union operation), induction of cryptorchidism or bilateral sham operation. The epididymides were weighed and the epididymides and deferent ducts were examined with light- and electron-microscopy at days 30, 37, 44 and 58. Bilateral non-union operated epididymides and cryptepididymides had a significantly lower weight increase than controls, but the histology and diameter of epididymal tubules were unchanged. This indicates a true growth retardation and reduced length of epididymal tubules of non-union operated and cryptepididymides. For bilateral operations a positive correlation was found between the weight of epididymis and plasma levels of total testosterone as reported earlier. Unilaterally operated epididymides had a weight development significantly below contralateral controls, despite normal plasma levels of testosterone. It is concluded that the reduced-weight of unilaterally operated epididymides is the result of diminished local androgen stimulation from the ipsilateral testis. Non-union of testis and epididymis may have pathogenetic significance in maldescent of testis by a retarded growth of the ductal system.

Age-related changes in the concentration of cytosolic androgen receptors in the epididymis, vas deferens and seminal vesicle of maturing male mice

In this study, changes in the number of androgen binding sites that occur in cytosols of epididymis, vas deferens and seminal vesicle of mice from 10 to 90 days of age are described. Specific saturable binding of [3H]R-1881 by cytosols of the three organs at all time points studied and age-related differences in the number of binding sites measured were observed. Cytosolic androgen receptor levels in all three organs studied were found to decrease with increasing age, regardless of whether the binding was expressed relative to weight of tissue, cytosolic protein or cellular DNA. The most pronounced change in androgen receptor levels (from 442 to 50 fmol/mg protein) was observed in the epididymis between 10 and 30 days of age. In these three organs there was no significant correlation between androgen (testosterone + dihydrotestosterone) levels and the concentration of androgen binding sites.

Long-term alterations on the male mouse genital tract associated with neonatal exposure to cyproterone acetate biochemical data

The effects of neonatal administration of cyproterone acetate on the growth, hormone responsiveness, DNA and protein concentrations, protein profiles, protein synthetic patterns and nuclear androgen binding sites of epididymis, vas deferens and seminal vesicles were investigated in adult mice. The weight of epididymis and seminal vesicle was significantly depressed and the reductions observed were secondary to cellular hypoplasia in epididymis and to cellular hypotrophy in seminal vesicle. The 3 organs studied showed a limited response to exogenous androgens at adulthood. When assessed by the number of cells the response of the 3 organs was similar to that of controls but it was significantly reduced from 25 to 35% when measured in term of cellular concentration of proteins. The protein profiles from homogenates of whole organs and the protein synthetic patterns after [35S]methionine incorporation, analyzed by polyacrylamide gel electrophoresis, showed reproducible persistent alterations. The total number of nuclear androgen binding sites was significantly reduced in seminal vesicles.

Epididymal and vas deferens immaturity in cryptorchidism

Cryptorchidism is associated with impaired spermatogenesis and, at times, sterility. Early orchiopexy has been advocated as a possible means to prevent spermatogenic impairment and infertility in patients with cryptorchidism. This retrospective study is derived from data obtained from 74 cases that were observed during a period of approximately 10 years at our hospital. Particular attention was devoted to epididymal and vas deferens histological status. Of the 47 epididymides and vas deferens examined only 2 epididymides and 2 vas deferens showed histological maturity. The remainder showed varying degrees of immaturity that additionally correlated, when testicular tissue was available, with the presence of unfavorable testicular histological findings. Cryptorchidism is associated with changes in the gonads and spermatic duct system.

Postnatal development of epididymis and ductus deferens in the rat. A correlation between the ultrastructure of the epithelium and tubule wall, and the fluorescence-microscopic distribution of actin, myosin, fibronectin, and basement membrane

The postnatal maturation of regions of the epididymis and intragonadal segment of the deferens duct was studied in the rat by light- and transmission electron microscopy. Maturation of the genital duct starts in the distal cauda epididymidis and ductus deferens after one week of life, and one week later, in the more cranial segments of the epididymis. Epithelial principal cells and peritubular contractile cells are structurally mature 35 days after birth. The synchronous changes of these cells indicate that the same factors control their postnatal maturation. The epithelial principal cells obtain an endocytotic apparatus and long stereocilia, whereas peritubular cells acquire contractile features. These changes are associated with a progressive increase in the immunoreaction for smooth muscle actin in both cell types. Smooth muscle myosin is detected in the apical region of the epithelial cells and the peritubular cell cytoplasm by day one of postnatal development. The differentiation of contractile cells in the wall is accompanied by progressive organization of the pericellular matrix into a continuous basement membrane. Although fibronectin is visible at birth, it is gradually removed from the tubule wall.

Some effects of cimetidine on the reproductive organs of rats

The development of genital organs of rats chronically treated with cimetidine showed that the drug may present anti-androgenic activity. This treatment did not alter the sensitivity of vas deferens to noradrenaline, but increased their sensitivity to BaCl2. In the male reproductive system, cimetidine must have peripheral actions apart from the central ones observed after chronic treatment.

Identification and androgen-dependence of proteins in the mouse vas deferens

Proteins from 'luminal fluid' or from a homogenate of whole vas deferens were analysed by polyacrylamide gel electrophoresis under denaturing conditions. Four major bands with apparent molecular weights of 34.5, 36, 38 and 180 Kilodaltons (K) were observed in homogenates. In 'luminal fluid' the same protein pattern was observed except that 38 K band was missing. These four major bands probably originated from the vas deferens as they were not detected in plasma and were still present after ligation between the epididymis and vas deferens. After castration, there was a specific reduction of the 34.5 K MW protein band in both homogenate and 'luminal fluid'. When the androgen-dependence of proteins was investigated using radioactive methionine, the protein spectra from normal and castrated males showed that about 10 polypeptides were differentially induced or repressed by androgens. The synthesis of some proteins (MW's 24, 36 and 180 K) was decreased by castration while the synthesis of several others (MW's between 27 and 82 K) was increased. Most of these androgen-dependent proteins were detectable at 10 days of age.

Post-natal change in the effect of denervation on the rat vas deferens

The vas deferens of 14-54 d old rats was denervated, isolated after 7 d, divided into prostatic and epididymal halves, and denervation supersensitivity to noradrenaline, acetylcholine, methacholine and tetramethylammonium (TMA) was examined. The supersensitivity to any of these agonists did not appear in rats younger than 21 d of age. Thereafter a leftward shift of the dose-response curve and an increase in the maximum contraction to noradrenaline were observed. The maximum contraction became progressively greater with development in the prostatic half but was approximately constant in the epididymal half. Supersensitivity to methacholine distinctly developed with age in the epididymal half. Only a subsensitivity to TMA was observed, suggesting that TMA acts on the nerve. The effect of denervation on the response to acetylcholine in the epididymal half resembled that to methacholine, and in the prostatic half resembled that to TMA. The developmental change in the effect of denervation on noradrenaline was discussed in relation to the full contractile ability of the vas halves, and that to cholinergic drugs was discussed in relation to nicotinic and muscarinic receptor population.

Post-natal change and regional variation of the response of the vas deferens of new-born rats to autonomic drugs

The vas deferens isolated from rats of different ages (11-60 d old) was bisected to provide an epididymal and a prostatic half. The contractile responses of both halves to potassium ions, adrenergic agents (noradrenaline, isoprenaline and tyramine), cholinergic agents (acetylcholine, methacholine and tetramethylammonium), histamine and serotonin were measured. The response to 150 mM potassium, which was regarded as an approximate measure of full contractility of the preparation, increased in parallel with the organ weight. Most of the agonists could induce the full contractility in both halves until 3-4 weeks of age, but thereafter they could produce only smaller responses than the full contractility in either or both halves, resulting in a differentiation of the halves in the response to agonists. A regional variation of the post-natal development of alpha-adrenergic, muscarinic and nicotinic responses is discussed.

Post-natal development of functional neurotransmission in rat vas deferens

Responses of the rat vas deferens to drugs and to field stimulation were examined in sexually immature rats. The vasa from immature rats often exhibited spontaneous contractions and displayed greater sensitivity to the contractile effects of alpha-adrenoceptor agonists. The responses of the vasa from immature rats to single pulse field stimulation lacked the adrenergic component of the response although the non-adrenergic component was present. The responses were antagonized by alpha 2-adrenoceptor agonists. In the presence of cocaine, an adrenergic component of the response did appear. During trains of pulses the pre- and postjunctional effects of adrenergic transmission which are found in adult rats were absent in vasa from immature rats. Electron microscopic studies showed no qualitative differences in adrenergic innervation in vasa from immature and adult rats. It is concluded that a state of 'pre-innervation supersensitivity' associated with a lack of functional adrenergic transmission exists in the vas deferens of immature rats. The supersensitivity disappears and functional transmission develops during the period in which testosterone secretion increases in the rat. The reason for the lack of functional transmission at a time when the innervation appears to be morphologically mature is not clear but may be due to the noradrenaline release mechanism not being fully operative.

Opioid effects in developing rat vas deferens

The inhibitory effects of various opiates on developing rat vas deferens were studied by determining the degree of depression of mechanical responses elicited by electrical field stimulation. All agonists showed decreased effects with maturation, but the decrease occurred at different times. With normorphine the loss of agonist activity was greatest at days 12-16, while with D-Met2,Pro5-enkephalinamide it was greatest at days 16-30. beta-Endorphin also was less effective in adult than 30-day preparations, but methionine enkephalin was ineffective at all ages. Morphine and normorphine were weak antagonists of opiate agonists in the adult preparations. These results indicate that the nature and pharmacologic sensitivity of opiate actions change with development.

Excitability ot beta-endorphin, morphine and catecholamines of the vas deferens of the rat at different stages of development

The effect of beta-endorphin and morphine on neuromuscular twitching of the vas deferens was examined in rats of 10-120 days of age. The maximal tension developed by the smooth muscle was markedly dependent on the age of the rat and on the kind of stimulus applied. The potency of beta-endorphin to inhibit the electrically induced twitching or of catecholamines to induce muscle contraction was not significantly altered by development of the animal. The excitatory action of morphine showed significant variations in activity reaching maximal sensitivity at about two months of age. Age or the onset of puberty do not significantly modify the sensitivity of the vas deferens to beta-endorphin, the peptide may play the role of modulating adrenergic transmission.

Morphological changes in the mammalian vas deferens during aging. I. The occurrence of binuclear cells in the mouse

The number of nuclei per principal cell was determined in the vas deferens of sexually immature, young sexually mature and old male mice. The incidence of binucleation increased with age. In 21-day-old mice approximately 99% of the principal cells were mononucleated and 9%-20% of the principal cells were binucleated. In the oldest animals, the ampulla and testis end of the vas usually had more binuclear cells than the middle segment. The biological significance and the mechanism of this phenomenon are not known; however, binucleation may prove to be a useful indicator of aging in the vas of this species. In addition, the mouse vas may provide a useful model for studies of binucleation and mitosis.