Histological, histochemical and ultrastructural variations along the length of the human vas deferens before and after puberty

The Role of Androgen Signaling in Male Sexual Development at Puberty

Puberty is characterized by major changes in the anatomy and function of reproductive organs. Androgen activity is low before puberty, but during pubertal development, the testes resume the production of androgens. Major physiological changes occur in the testicular cell compartments in response to the increase in intratesticular testosterone concentrations and androgen receptor expression. Androgen activity also impacts on the internal and external genitalia. In target cells, androgens signal through a classical and a nonclassical pathway. This review addresses the most recent advances in the knowledge of the role of androgen signaling in postnatal male sexual development, with a special emphasis on human puberty.

Immunohistochemical Study of the Goat Ductus deferens

Ductus deferens plays an important role in sperm transport and participates in the preservation of structure, maturation, and viability of sperm. In this study, we have immunohistochemically examined the ductus deferens in the goat. For immunohistochemical study the following monoclonal antibodies were used: cytokeratin 18, α-smooth muscle actin (α-SMA), vimentin and elastin. Morphologically, three distinct layers were identified in the goat ductus deferens — tunica mucosa, tunica muscularis and tunica adventitia. The epithelium of the mucosa was intensely stained with cytokeratin 18 (CK 18). The fibroblasts in the lamina propria and blood capillaries in the muscle layer showed positive reaction for vimentin. A positive reaction for α-SMA was observed in the smooth muscle cells of the tunica muscularis in the internal, middle and outer sublayers. An intense positive reaction for α-SMA was observed in the wall of the blood vessels. Elastic fibers in the form of a loose meshwork were present in all three layers. The high density of elastic fibers were found in the tunica adventitia.

Sperm dysfunction and ciliopathy

Sperm motility is driven by motile cytoskeletal elements in the tail, called axonemes. The structure of axonemes consists of 9 + 2 microtubules, molecular motors (dyneins), and their regulatory structures. Axonemes are well conserved in motile cilia and flagella through eukaryotic evolution. Deficiency in the axonemal structure causes defects in sperm motility, and often leads to male infertility. It has been known since the 1970s that, in some cases, male infertility is linked with other symptoms or diseases such as Kartagener syndrome. Given that these links are mostly caused by deficiencies in the common components of cilia and flagella, they are called "immotile cilia syndrome" or "primary ciliary dyskinesia," or more recently, "ciliopathy," which includes deficiencies in primary and sensory cilia. Here, we review the structure of the sperm flagellum and epithelial cilia in the human body, and discuss how male fertility is linked to ciliopathy.

Bicarbonate exchangers SLC26A3 and SLC26A6 are localized at the apical membrane of porcine vas deferens epithelium

The goal of this study was to test for expression of HCO3 (-) exchangers SLC26A3 and SLC26A6 in primary cultures of porcine vas deferens epithelial cells (1°PVD) and native porcine vas deferens. Quantitative RT-PCR revealed that mRNA coding for SLC26A6 was six times more abundant than mRNA coding for SLC26A3 in 1°PVD cells. Western blot analyses combined with surface biotinylation of 1°PVD demonstrated SLC26A3 and SLC26A6 immunoreactivities in whole-cell lysates and apical surfaces of monolayers. Laser scanning confocal microscopy (LSCM) of the 1°PVD cell monolayers demonstrated that SLC26A3 immunoreactivity was primarily in the apical region but present throughout the basal-apical cellular axis, whereas SLC26A6 immunoreactivity was present in the apical region and sometimes accumulated in the nuclear region. LSCM also demonstrated SLC26A3 and SLC26A6 immunoreactivities present along the entire apical lining of the native porcine vas deferens epithelium and in basal cells. The patterns and apparent abundance of SLC26A3 and SLC26A6 immunoreactivities in the proximal vas deferens were not different from the corresponding immunoreactivities in the distal region. There is no evidence of preferential expression of SLC26A3 or SLC26A6 in any portion of the vas deferens, as has been proposed for epithelia that secrete HCO3 (-) in other duct systems. Thus, vas deferens epithelia express transporters throughout the duct that can contribute to rapid alkalinization of the luminal contents as it has been demonstrated in vivo.

Ejaculatory dysfunction

Ejaculatory dysfunction may occur after many different disorders ranging from traumatic spinal cord injury to diabetes mellitus. With an understanding of the many facets and nuances of the ejaculatory apparatus, both anatomic and neurologic, the well-versed clinician can proceed along a safe, efficient, and appropriate treatment algorithm to help affected men and their partners achieve parenthood.

NF-kB overexpression and decreased immunoexpression of AR in the muscular layer is related to structural damages and apoptosis in cimetidine-treated rat vas deferens

BACKGROUND

Cimetidine, histamine H2 receptors antagonist, has caused adverse effects on the male hormones and reproductive tract due to its antiandrogenic effect. In the testes, peritubular myoid cells and muscle vascular cells death has been associated to seminiferous tubules and testicular microvascularization damages, respectively. Either androgen or histamine H2 receptors have been detected in the mucosa and smooth muscular layer of vas deferens. Thus, the effect of cimetidine on this androgen and histamine-dependent muscular duct was morphologically evaluated.

METHODS

The animals from cimetidine group (CMTG; n=5) received intraperitoneal injections of 100 mg/kg b.w. of cimetidine for 50 days; the control group (CG) received saline solution. The distal portions of vas deferens were fixed in formaldehyde and embedded in paraffin. Masson´s trichrome-stained sections were subjected to morphological and the following morphometrical analyzes: epithelial perimeter and area of the smooth muscular layer. TUNEL (Terminal deoxynucleotidyl-transferase mediated dUTP Nick End Labeling) method, NF-kB (nuclear factor kappa B) and AR (androgen receptors) immunohistochemical detection were also carried out. The birefringent collagen of the muscular layer was quantified in picrosirius red-stained sections under polarized light. The muscular layer was also evaluated under Transmission Electron Microscopy (TEM).

RESULTS

In CMTG, the mucosa of vas deferens was intensely folded; the epithelial cells showed numerous pyknotic nuclei and the epithelial perimeter and the area of the muscular layer decreased significantly. Numerous TUNEL-labeled nuclei were found either in the epithelial cells, mainly basal cells, or in the smooth muscle cells which also showed typical features of apoptosis under TEM. While an enhanced NF-kB immunoexpression was found in the cytoplasm of muscle cells, a weak AR immunolabeling was detected in these cells. In CMTG, no significant difference was observed in the birefringent collagen content of the muscular layer in comparison to CG.

CONCLUSIONS

Cimetidine induces significant damages in the epithelium; a possible antiandrogenic effect on the basal cells turnover should be considered. The cimetidine-induced muscle cells apoptosis confirms the susceptibility of these cells to this drug. The parallelism between enhanced cytoplasmic NF-kB immunolabeling in the damaged muscular tissue and muscle cell apoptosis suggests that this drug may avoid the translocation of NF-kB to the nucleus and interfere in the control of NF-kB-mediated smooth muscle cell apoptosis. The decreased immunoexpression of ARs verified in the damaged muscular tissue reinforces this possibility.

Ultrastructural evidence for secretion from the epithelium of ampulla ductus deferentis of the fan-throated lizardSitana ponticeriana Cuvier

Among reptiles, an ampulla ductus deferentis has been reported only in Squamata. Fairly detailed studies are available only for two species, the lizard Calotes versicolor (Fam: Agamidae) and the snake Seminatrix pygaea (Fam: Colubridae). The light microscopic study on C. versicolor revealed the ampulla to be a prominent organ, whereas the light and transmission electron microscopic study in S. pygaea revealed it to be discernable only in histological preparations. Further, the epithelium of the ductal portion of vas deferens as well as the ampulla of C. versicolor appears to contribute to the seminal plasma and can also phagocytose dead sperm, whereas in S. pygaea neither of these roles has been established. Thus, we hypothesize that there may be variations in the anatomy, histology, and the role of the vas deferens in general, and the ampulla in particular, of the squamate reptiles. In this study, the ductus deferens of the small fan-throated lizard Sitana ponticeriana (Fam: Agamidae) was subjected to light and transmission electron microscopic analysis. In this lizard the ampulla is more prominent than in C. versicolor. The epithelium of the ductal portion of vas deferens consists of principal cells (with features reflecting roles in endocytosis and phagocytosis of dead sperm), dark cells (which are absent in the epithelium of the ductal portion of vas deferens of snakes), and basal cells. The ampulla of S. ponticeriana is differentiated into storage and glandular portions. The epithelium of the storage portion is like that in the ductal portion of the vas deferens, whereas that of the glandular portion, consisting of dark and light principal cells and foamy cells, is tall and forms into smooth villous folds. All three cell types show evidence for a role in secretion, in all likelihood different from each other, for release into the lumen to contribute to seminal plasma. These cells do not provide evidence of a role in phagocytosis of dead sperm. It appears that within the Squamata, the ductal ampulla differs in structure as well as function. We suggest that the ductal ampulla of agamid lizards is a composite gland of the ampulla ductus deferentis and seminal vesicles of mammals.

Lectin histochemistry study in the human vas deferens

The oligosaccharide sequences of glycoconjugates in the normal human vas deferens and the nature of the saccharide linkage were studied by lectin histochemistry. The cytoplasm of all epithelial cell types (principal cells, basal cells, and mitochondria-rich cells) and luminal contents reacted positively with WGA, MAA, PNA, DSA, LTA, UEA-I, AAA, and ConA. The reaction was more intense in the stereocilia of principal cells. Cytoplasmic staining was diffuse except for PNA and DSA labeling which was limited to the apical cytoplasm and stereocilia of columnar cells. The cytoplasm of all cell types also reacted diffusely with HPA, although staining was weak and was not observed in the stereocilia. Positive reaction with SBA only was encountered in the stereocilia of principal cells. SNA, LTA, and DBA were unreactive. GNA-labeling showed a granular distribution in the supranuclear cytoplasm of columnar epithelial cells. Reactions with MAA, PNA, DSA, AAA, HPA and SBA disappeared after the beta-elimination reaction. Reactions with WGA and UEA-I decreased after beta-elimination or Endo-F digestion. Reactions with ConA and GNA were suppressed by Endo-F digestion. Reactions with PNA, HPA, and SBA increased after desialylation. Of all the lectins that label the luminal contents of the vas deferens, only UEA-I was not found in the luminal contents of seminiferous tubules and epididymis and, thus, this lectin would probably bind to glycoproteins secreted by the vas deferens. The chemical treatments used suggest that this secretion contains fucose residues located in both N- and O-linked oligosaccharides. The other lectins may label secreted proteins, but also structural proteins or proteins reabsorbed from the luminal fluid. The lectin- binding pattern of mitochondria-rich cells in the vas deferens differed from that found in the epididymis.

Scanning electron microscopy of vas deferens epithelium after temporary alteration caused by radiopaque medium

Nine male rats (Rattus norvegicus albinus) weighing approximately 300 g were divided into 3 groups: a control group (CG), an experimental group of 7 days (EG-7), and an experimental group of 35 days (EG-35). All rats except those in the control group underwent a left vasography. The EG-7 and EG-35 rats were killed on the 7th and 35th days, respectively, after vasography; CG rats were killed on a randomly chosen day. The histological sections and scanning electromicrographs showed that the temporary alterations caused by radiopaque medium on vas deferens mucosa seen on the 7th day after vasography were completely repaired on the 35th day of recovery and either apical secretion or stereocilia of principal cells were reestablished.

Quantification and distribution of alpha 1-adrenoceptor subtype mRNAs in human vas deferens: comparison with those of epididymal and pelvic portions

1. This study was intended to quantify the amounts of the alpha 1-adrenoceptor subtype mRNAs in human vas deferens, and demonstrate the receptor subtype responsible for the vas contraction. 2. The RNase protection assay showed that the mean total amount of alpha 1a mRNA was 7.4 +/- 2.2 pg/5 micrograms of poly (A)+ RNA (97.0% of the total alpha 1 mRNA) in the epididymal portion (E-vas) and 4.9 +/- 0.8 pg/5 micrograms of poly (A)+ RNA (96.3% of the total) in the pelvic portion (P-vas). The E-vas showed a tendency to have a greater alpha 1a mRNA abundance than the P-vas (P = 0.11). The alpha 1b and alpha 1d mRNAs were absent or of extremely low abundance. 3. By an in situ hybridization, the alpha 1a and alpha 1d mRNAs were recognized in the smooth muscle cells of the E-vas and the P-vas, and the distribution pattern the same in both tissue. The alpha 1b mRNA positive site was scarcely detectable in both vas portions. 4. In a functional study, l-phenylephrine produced concentration-dependent contraction in the E-vas (Emax = 2.24 +/- 0.70 g; pD2 = 5.32 +/- 0.09) and the P-vas (Emax = 2.46 +/- 0.46 g; pD2 = 5.07 +/- 0.12). KMD-3213, a novel alpha 1A-adrenoceptor-selective antagonist, caused parallel rightward shifts of the concentration-response curves for l-phenylephrine. Apparent pKB values were 9.90 +/- 0.16 for the E-vas and 9.71 +/- 0.17 for the P-vas. There was no significant difference in Emax, pD2 or pKB estimates between the two portions. 5. We have found that alpha 1a mRNA is predominant in the human vas deferens, and confirmed that contraction of this organ is mediated by the alpha 1A-adrenoceptor.

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.

Diverticula of the ductus epididymis in men

The histological study of epididymides obtained from autopsies (41 children, 7 young adults and 8 elderly men) and surgical specimens (10 young adults and 3 elderly men) revealed the presence of multiple diverticula in the cauda epididymis in all elderly men and in only 2 young adults (32 and 33 years old). The diverticula appeared as evaginations of the epithelial lining of the duct, disrupting the muscular coat and expanding into the surrounding connective tissue. The formation of epididymal diverticula seems to be an age-related process that might be caused by repeated increases in the intraluminal pressure in the cauda epididymis.

Ultrastructural changes in Sertoli cells in ageing humans

Ultrastructural study of seminiferous tubules in ageing men revealed a varying degree of spermatogenetic arrest associated with changes in the Sertoli cells. Approximately half of the Sertoli cells showed a normal mature nuclear appearance although the cytoplasm was altered morphologically. These cells were classified as containing abundant lipid droplets (30%), containing large cytoplasmic vacuoles filled with an amorphous material similar to that in the tubule lumen and surrounded by junctional specializations (8%), multinucleated Sertoli cells (4%), or Sertoli cells with numerous mitochondria displaying tubular cristae (2%). The remaining 7% of Sertoli cells had an immature nuclear appearance and sparse development of the cytoplasmic organelles; these cells probably represent dedifferentiated Sertoli cells. Although individual differences were marked, a correlation between the increase in gonadotrophin levels and changes in both germ cell development and Sertoli cell structure was observed.