Immunolocalization of androgen receptor in the epididymis of rats with dihydrotestosterone deficiency

Dihydrotestosterone (DHT), 5alpha-reduced metabolite of testosterone, is the most potent androgen in the epididymis. The conversion of T into DHT is carried out by 5alpha-reductase. The activity of 5alpha-reductase type 2, preferentially expressed in the epididymis can be inhibited by a finasteride (a steroid-based specific inhibitor of 5alpha-reductase type 2) which results in DHT deficiency. The aim of the study was to examine the morphology of epididymis and the immunolocalization of an androgen receptor (AR) in the initial segment, caput and cauda epididymis of rats treated with finasteride for 56 days. There were no morphological changes in the morphology of epididymal epithelium in the experimental rats. Immunostainable AR was localized in nuclei of epithelial cells, smooth muscle cells and mainly in the cytoplasm of interstitial cells in the epididymis of control rats. In the epididymis of experimental rats, AR immunostaining was noticed mainly in the cytoplasm of epithelial cells and interstitial cells. The single cells of the initial segment epithelium, basal cells and smooth muscle cells of cauda epididymis showed nuclear AR staining. In conclusion, finasteride affected the expression of the AR in the rat epididymis without changing the morphology of epididymal epithelium. Altered AR expression reflected the hormonal status within the epididymis.     

Ethylene dimethane sulfonate (EDS) ablation of Leydig cells in adult rat depletes testosterone resulting in epididymal sperm granuloma: Testosterone replacement prevents granuloma formation

Sperm granuloma may develop in the epididymis following vasectomy or chemical insults. Inflammation due to sperm granuloma causes abdominal and scrotal pain. Prolonged and persistent inflammation in the epididymis due to sperm granuloma may lead to infertility. Extravasation of germ cells into the interstitium of epididymis following damage of the epididymal epithelium is one of the primary reasons for sperm granuloma-associated pathology. Since testosterone is vital for the maintenance of epididymal epithelium, we investigated the pathology of sperm granuloma and its relationship with testosterone. Adult rats were treated with a Leydig cell-specific toxicant ethylene dimethane sulfonate (EDS) to eliminate testosterone. At 7 days post-EDS, disrupted epididymal epithelium and sperm granuloma were observed in the caput epididymis. Sperm granuloma and caput were collagen-filled indicating fibrosis. Numerous round apoptotic cells were localized inside the caput lumen and dispersed through the sperm granuloma. Tnp1 (round spermatid marker) was significantly higher in the epididymis of the EDS-treated group compared to controls suggesting the apoptotic cells were round spermatids. Increases in CD68⁺ macrophages and T cells (CD4 and CD8) support an inflammatory immune infiltration in post-EDS epididymis. However, testosterone replacement following EDS prevented the sperm granuloma-associated pathology. We suggest that the immune response in the sperm granuloma may be due to the increased numbers of apoptotic round spermatids or other testicular tissue components that may be released, in addition to the regression of epididymal epithelium due to testosterone loss. Thus, testosterone replacement prevents EDS-induced sperm granuloma and ameliorates sperm granuloma-associated pathology.     

Morphological changes in the testis and epididymis of rats treated with cyclophosphamide: a quantitative approach

Cyclophosphamide is a widely used anticancer and immunosuppressive drug that affects fertility in men. In a previous study, we found that chronic, daily treatment of male rats with low doses of cyclophosphamide had no apparent effect on the pituitary-gonadal axis, whereas it had time- and dose-dependent effects on male reproductive organ weights, the hematologic system, and on pregnancy outcome. To determine whether cyclophosphamide induces morphological changes within the male reproductive system, a detailed qualitative and quantitative evaluation of changes in the histology of the testis and epididymis was undertaken. Adult male Sprague-Dawley rats were gavage-fed for 1, 3, 6, and 9 wk with saline (control), 5.1 (low dose) or 6.8 (high dose) mg/kg/day of cyclophosphamide; the testes and epididymides were prepared for light and electron microscopy. At the light microscopic level, the orderly process of spermatogenesis in the seminiferous tubules was not affected at any time point with either dose of the drug. A number of time-dependent drug-induced changes in the histology of the epididymis, however, were apparent: 1) an increase in the relative number and a change in the distribution of halo cells in the caput epididymidis, 2) an increase in the number and size of clear cells in the caput and/or cauda epididymidis, and 3) an increase in the size of clear cells in both the caput and cauda epididymides; these changes were time dependent. At the electron microscopic level, there was a dose-dependent, two- to threefold increase in the number of spermatozoa with abnormal flagellar midpieces in the lumen of both the caput and cauda epididymides. Although the 9 plus 2 axonemal complex and the 9 outer dense fibers were present and appeared normal, the close approximation of these two structures was lost in these abnormal spermatozoa. Such abnormal flagellar midpieces were also found in the testes of control and treated rats. Electron microscopic examination of the testis revealed that both Sertoli and Leydig cells were normal in appearance. The type and timing of the effects of cyclophosphamide on the histology of the testis and epididymis suggest that the drug could be affecting germ cells by 1) inducing changes in the developing spermatozoa in the testis, some of which are seen microscopically in the epididymal lumen, and/or 2) affecting epididymal morphology and function.     

Influence of hormonal imbalance on the integrity of seminiferous epithelium in the testes of adult rats chronically exposed to letrozole and rats exposed to soya isoflavones during the prenatal period,lactation, and up to sexual maturity

The structural integrity of the germ cells in the seminiferous epithelium and the correct process of spermatogenesis are made possible by proteins that participate in the formation of different types of junctions. This study was performed on samples of the testes of 4 groups (2 experimental and 2 corresponding control) of male Wistar rats. In the first experimental group, the adult rats received letrozole – a nonsteroidal inhibitor of cytochrome P450 aromatase (P450arom). The second experimental group was exposed to soya isoflavones during the prenatal period, lactation, and up to sexual maturity. The aim of this study was to examine the immunoexpression of β-catenin, N-cadherin, occludin, connexin43, annexin V, and advanced glycation end products (AGE) in the seminiferous epithelium of rat testes with chronic estrogen deficiency and of rats exposed to soya isoflavones. Series of sections of the testes were stained using PAS and silver impregnation. Moreover, immunohistochemistry tests were performed. A semi-quantitative determination of protein immunoexpression was performed using Image J. The number of annexin V positive Sertoli cells per tubule were counted manually. Comparisons between the experimental and corresponding control groups were performed using a non-parametric Mann-Whitney U test. The most common alterations were prematurely sloughed germ cells in the lumen of the seminiferous tubules and invaginations of the seminiferous tubules. We observed a lower number of annexin V positive Sertoli cells and a lower expression of N-cadherin and occludin in the seminiferous epithelium of both groups of rats with hormonal imbalances. Moreover, a higher expression of AGE, a lower expression of connexin 43 and a lower amount of reticular fibers in the basal lamina of seminiferous tubules was present in rats treated with letrozole and a higher expression of β-catenin was found in rats exposed to soya isoflavones. The hormonal imbalance between androgens and estrogens resulted in a decreased number of annexin V positive Sertoli cells. This may be associated with a failed clearance of apoptotic germ cells that leads to disturbances in the blood-testis-barrier (BTB) by affecting the expression of junctional proteins in the seminiferous epithelium. Moreover, a decreased level of estrogens was also associated with an increased expression of AGEs and with a changed composition of basal lamina in the seminiferous tubules of rats. These changes could lead to germ cell sloughing and invaginations of the seminiferous tubules.     

Ultrastructural changes in cauda epididymidal epithelial cell types of Azadirachta indica leaf treated rats

To assess if cauda epididymis is a target for the effect of A. indica leaves, Wistar strain male albino rats were administered (po) A. indica leaves (100 mg/rat/day for 24 days). Transmission electron microscopic analysis revealed that in the cauda epididymal epithelium the nuclei of principal cells were enlarged and the number of coated micropinocytotic vesicles of the apical cytoplasm decreased. Microvilli were missing and mitochondrial cristae and Golgi complex were highly disrupted. The cytoplasm was abounding with lysosomal bodies. The clear cells increased in perimeter and their nuclei increased in size and contained lesser chromatin. The nuclear membrane bulged out. The cytoplasm was vacuolized. Further, there was decrease in size of the lipid droplets, mitochondria, Golgi complex, endoplasmic reticulum and there was accumulation of lysosomal bodies. The changes in the principal and clear cells appear to be due to the effect of the hypoandrogen status caused by treatment with A. indica leaves and a direct action on the epididymal epithelium.     

Distribution of immune cells in the epididymis of the aging Brown Norway rat is segment-specific and related to the luminal content.

Remarkable changes occur during aging in the testis and epididymis of the Brown Norway rat. A dramatic increase in the number of halo cells, which are present in the epididymal epithelium and originate from the immune system, is found in animals of increasing age. Halo cells have been postulated to be either lymphocytes or monocytes. We hypothesized that halo cells are a mixture of different immune cells and that their relative composition changes with age. To verify this hypothesis, markers for helper T lymphocytes, cytotoxic T lymphocytes, B lymphocytes, and monocytes-macrophages were used to identify the major categories of immune cells in the epididymides of Brown Norway rats ranging in age from 3 to 24 mo. The numbers of immunocompetent cells in the epididymis were determined in relation to age, epididymal segment, and luminal content. We found that monocytes, helper T lymphocytes, and cytotoxic T lymphocytes belong to the population of halo cells. In addition, a segment-specific increase with age in the number of these immune cells was noted. Finally, we report a segment-specific recruitment of cytotoxic T lymphocytes and monocytes-macrophages in the epididymal epithelium of aged rats whose epididymal lumen contained few spermatozoa. We postulate that accumulation of damaged epithelial cells and antigens of germ cell origin, leaking through a dysfunctional blood-epididymis barrier, may contribute to the active recruitment of immune cells with age.     

Lactate dehydrogenase activity of rat epididymis and spermatozoa: effect of constant light

During its passage through the epididymis, the gamete undergoes a process of "maturation" leading to the acquisition of its fertilizing ability. The epididymis displays regional variations in the morphology and metabolic properties of its epithelium which are relevant for the progressive development of mature sperm characteristics. The epididymis has spontaneous peristaltic contractions and receives sympathetic innervation that is modulated by melatonin, a hormone synthesized and released by the pineal gland. Constant lighting disrupts melatonin synthesis and secretion. We have studied the effect of constant light on lactate dehydrogenase (LDH; EC 1.1.1.27) and its isozyme C4 activities and protein content in whole epididymis, epididymal tissue and in spermatozoa from caput and cauda segments. Animals were exposed from birth to an illumination schedule of 14 h light:10 h dark (group L:D). At 60 days of age one group of animals was submitted to constant light over 50 days (group L:L). In order to test the fertilizing ability, the rats of each group were mated with soliciting estrous females. The percentage of pregnancies in females mated with males maintained in L:L was remarkably lower than those in females mated with males maintained in the L:D photoperiod (44% and 88% respectively). Constant light increased protein concentration and LDH activity in caput as well as in cauda of total epididymis. On the contrary, in epididymal tissue, the protein content decreased in both epididymal sections compared with controls. When enzymatic activity was expressed in Units per spermatozoa, constant light induced a significant reduction of total LDH and LDHC4 in caput and cauda spermatozoa while LDH activity of epididymal tissue was not affected. In spite of the decrease in LDH per sperm cell when rats were exposed to constant light, in total epididymis (epididymis tissue plus sperm cells content) and in spermatozoa, values of enzyme activities expressed per weight unit were higher than those of controls. This is explained by the increase in the amount of stored spermatozoa, both in caput and cauda, produced by exposure of animals to constant light. Our results confirm that in rats, chronic exposure to constant light promotes a reduction of fertilizing ability and indicates that continuous lighting reduces the total LDH and LDHC4 activities, possibly due to moderate aging of spermatozoa within the duct by lengthening of the sperm transit through the epididymis.     

Cell proliferation in the seminiferous and epididymal epithelia of Sus domesticus

It is important to understand the proliferative activity of the different structures of the male reproductive apparatus in livestock species, such as Sus domesticus, to ensure reproductive efficiency. The main aims of this study were (a) to evaluate the proliferative activity of the spermatogonia in the different stages of the seminiferous cycle and (b) to study the cell proliferation in the epididymal epithelium in each region, identifying the different cells involved. For this, the testes and epididymis of three healthy, sexually mature Sus domesticus boars were used. The organs were processed for light microscopy, and immunohistochemical techniques were used to detect proliferating cell nuclear antigen. The cells immunostaining positively and negatively for proliferating cell nuclear antigen were counted and several parameters and indexes were calculated to evaluate the proliferation in both epithelia, taking into account the stage of the seminiferous epithelium cycle, and, in the case of the epididymal epithelium, the different regions and cells are the same. Finally, a contrast analysis of equality between pairs of means was carried out followed by a least significant differences test, in which differences were considered significant at P < 0.05. In the seminiferous epithelium, the greatest total number of spermatogonia and proliferating spermatogonia was observed in the postmeiotic stages (mainly VII and VIII). The proliferation index of the spermatogonia increased from the meiotic to postmeiotic stages. As regards the epididymal epithelium, the total proliferation index was higher in the caput. In each region, the clear and principal cells showed the highest proliferation index with respect to the total number of cells counted, whereas the proliferation index of each cell with respect to the same type was higher in the clear cells, followed by the narrow and principal cells. In conclusion, the proliferative activity of spermatogonia in the seminiferous epithelium of Sus domesticus is stage-dependent, and mainly occurs in the postmeiotic stages. In the epididymal epithelium, proliferative activity takes place in several cell types and is dependent on the anatomical region of the epididymis. We think that these results may be of importance for understanding the pathologic or reproductive processes in which cell proliferation is involved in the male reproductive system.     

Morphology and immunolocalization of aquaporins 1 and 9 in the agouti (Dasyprocta azarae) testis excurrent ducts

This study investigated the morphology and immunoexpression of aquaporins (AQPs) 1 and 9 in the rete testis, efferent ducts, epididymis, and vas deferens in the Azara’s agouti (Dasyprocta azarae). For this purpose, ten adult sexually mature animals were used in histologic and immunohistochemical analyses. The Azara’s agouti rete testis was labyrinthine and lined with simple cubic epithelium. Ciliated and non-ciliated cells were observed in the epithelium of the efferent ducts. The epididymal cellular population was composed of principal, basal, apical, clear, narrow, and halo cells. The epithelium lining of vas deferens was composed of the principal and basal cells. AQPs 1 and 9 were not expressed in the rete testis. Positive reaction to AQP1 was observed at the luminal border of non-ciliated cells of the efferent ducts, and in the peritubular stroma and blood vessels in the epididymis, and vas deferens. AQP9 was immunolocalized in the epithelial cells in the efferent ducts, epididymis and vas deferens. The morphology of Azara’s agouti testis excurrent ducts is similar to that reported for other rodents such as Cuniculus paca. The immunolocalization results of the AQPs suggest that the expression of AQPs is species-specific due to differences in localization and expression when compared to studies in other mammals species. The knowledge about the expression of AQPs in Azara’s agouti testis excurrent ducts is essential to support future reproductive studies on this animal, since previous studies show that AQPs may be biomarkers of male fertility and infertility.     

Spermatotoxic effects of α-chlorohydrin in rats

This study was conducted to investigate the potential effects of α-chlorohydrin (ACH) on epididymal function and antioxidant system in male rats. The test chemical was administered to male rats by gavage at doses of 0, 3, 10, and 30 mg/kg/day for 7 days. Twenty-four male rats were randomly assigned to four experimental groups, with six rats in each group. Spermatotoxicity was assessed by measurement of reproductive organ weight, testicular sperm head count, epididymal sperm motility and morphology, histopathologic examination, and oxidative damage analysis in rats. At 30 mg/kg/day, an increase in the incidence of clinical signs, epididymis weight, and gross necropsy findings of the epididymis, a decrease in the sperm motility, and an increased incidence of histopathological changes of the epididymis were observed in a dose-dependent manner. At 10 mg/kg/day, an increased incidence of clinical signs and histopathological changes and decreased sperm motility were observed. In the oxidative damage analysis, an increase in the malondialdehyde concentration and a decrease in the glutathione content and glutathione peroxidase and catalase activities in the epididymal tissue were detected at ≥3 mg/kg/day. The results show that graded doses of ACH elicit depletion of the antioxidant defense system and that the spermatotoxicity of ACH may be due to the induction of oxidative stress.     

Testicular weight, tubular diameter and number of Sertoli cells in rats are decreased after early prepubertal administration of an LHRH-antagonist; the quality of spermatozoa is not impaired

To suppress gonadotropin secretion during the sensitive period in development of the testes, immature male rats were treated with an antagonist of luteinizing hormone-releasing hormone (LHRH; ORG. 30276) from postnatal days 6-15. Previously, it has been demonstrated that this treatment results in delayed pubertal development, decreased testicular weight, impaired fertility and adult sexual behavior. In the present experiments it was investigated whether the decreased testicular weight was correlated with morphological changes in the testis. Also, by using an artificial insemination technique, the biological activity of spermatozoa of adult male rats, treated during early prepuberty with the LHRH antagonist (LHRH-A), was tested. The present results demonstrated a decrease in the diameter of the testicular tubuli of LHRH-A-treated rats. The number of Sertoli cells per tubular cross-section was also smaller. But qualitatively no differences could be observed in the testis. All stages of maturation of the seminiferous epithelium were equally frequently represented in LHRH-A-treated males compared with controls. Artificial insemination using spermatozoa obtained from the epididymis of LHRH-A-treated rats, resulted in a pregnancy rate of 100%, similar to the control rate. From the present data, we conclude that the infertility in adult male rats, treated with an antagonist to LHRH during prepubertal life, does not result from malfunction in the maturational processes in the germinal cells and the testes as a whole, despite the observation of changes in the testicular morphology. The infertility of LHRH-A-treated male rats can be explained by the observed impairment of sexual behavior. We suggest, that a central action of the antagonist of LHRH when administered to immature male rats may lead to permanent changes in the development of sexual behavior.     

Expression of aquaporin 9 in the adult rat epididymal epithelium is modulated by androgens

Reabsorption of fluid and solutes across the epithelium lining the male excurrent duct is important for adequate sperm maturation, concentration, and storage. Water channels contribute to water movement across epithelia in many tissues. Aquaporin 9 (AQP9) is abundantly expressed in the apical membrane of principal cells that line the epididymis, and in reabsorptive and secretory epithelial cells of the male reproductive tract. In this study we show that the nonsteroidal antiandrogen flutamide, given to adult rats at a dose of 50 mg x kg(-1) x day(-1) for 2 wk via osmotic minipumps significantly decreased the amount of AQP9 in the epididymis. This down-regulation was observed by immunofluorescence of cryostat tissue sections and by Western blotting of epididymal brush border membrane preparations. In addition, castrated adult rats showed lower levels of epididymal AQP9 compared with adult controls, whereas systemic testosterone treatment of castrated adult rats induced a recovery of the expression of AQP9 to control levels. These data indicate that the expression of AQP9, a likely candidate for apical transepithelial fluid and solute transport in several regions of the male reproductive tract, is modulated by androgens in the adult rat epididymis.     

The expression of inducible nitric oxide synthase (iNOS) in the testis and epididymis of rats with a dihydrotestosterone (DHT) deficiency

In our previous studies, we showed that a finasteride-induced DHT deficiency may cause changes in the morphology of the seminiferous epithelium without any morphological alteration of the epididymis. In this study, we demonstrated the constitutive immunoexpression of inducible nitric oxide synthase (iNOS) in the testis and epididymis of Wistar rats treated with finasteride for 28 days (the duration of two cycles of the seminiferous epithelium) and 56 days (the duration of one spermatogenesis). We noted that a 56-day finasteride treatment mainly caused a decrease in the level of circulating DHT, as well as a statistically insignificant decrease in the level of T. The hormone deficiency also led to a change in the iNOS immnoexpression in the testis and epididymis of the finasteride-treated rats. In vitro, DHT did not modify NO production by the epithelial cells of the caput epididymis even when stimulated with LPS and IFNγ, but it did give rise to an increase in NO production by the epithelial cells of the cauda epididymis without the stimulation. DHT did not have a statistically significant influence on estradiol production by cultured, LPS- and IFNγ-stimulated epithelial cells from the caput and cauda epididymis. In conclusion, our data clearly indicates that a finasterideinduced DHT deficiency intensifies the constitutive expression of iNOS in most rat testicular and epididymal cells, so it can be expected that the expression of inducible nitric oxide synthase (iNOS) could be regulated by DHT. On the other hand, the profile of the circulating DHT and T levels strongly suggests that the regulation of constitutive iNOS expression is complex and needs more detailed study.     

Masking of sperm maturation antigen by sialic acid in the epididymis of the mouse. An immunohistochemical study

Sperm antigen expression during epididymal transit was examined in 4- to 16-week-old intact and castrated ICR mice, using the avidin-biotin complex (ABC) immunohistochemical method with monoclonal antibody T21 against a flagellar surface antigen. On untreated sections, the antigen was first expressed weakly on sperm in the proximal part of the corpus epididymis, and intraluminal components were stained in 4-week-old mice. Epididymal epithelial cells and their stereocilia, and cells in other reproductive organs were not stained. In contrast, on sections treated with neuraminidase, (1) the initial site of antigen appearance is a more proximal position in treated than in untreated sections, (2) stereocilia stained strongly, (3) the staining intensity of sperm and intraluminal components increased, and (4) some clear cells in the epithelium from the distal position of the caput to the corpus epididymis were stained. These results indicate that the antigen is produced by clear cells of the epididymal epithelium, that the antigenic determinant is masked initially by sialic acid residues, and that expression of the antigenic determinant on the sperm surface during epididymal maturation apparently involves desialylation.     

Histochemical studies of the rat epididymis after treatment with alpha-chlorohydrin (U-5897)

Histochemical studies of the rat epididymis after treatment with alp ha-chlorohydrin (U-5897) are presented. 14 sexually mature male rats received either daily subcutaneous injections of 50 mg U-5907/kg body weight or distilled water for 20 days. The animals were sacrificed the day following the last injection. U-5897 induced temporary sterility as demonstrated by blocked transport of spermatozoa, and spermatogenic cells eliminated from the spermatogenic epithelium which became blocked in the caudal part of the epididymis. This resulted in the distension of the segment of the distal part of the epididymal duct and to the thinning of the epithelium which lined the altered segment. Alkaline and acid phosphatases, nonspecific esterases, succinate and glucose-6-phosphate dehydrogenases and reduced nicotinamide-adenine dinucleotide tetrazolium reductase in the unchanged part of the epididymal duct were comparable to control rats whereas the altered part of the epididymis showed these activities to much weaker degrees or to be absent altogether.     

Ultrastructural and biochemical seasonal changes in epididymal corpus and cauda of viscacha (Lagostomus maximus maximus)

The reproductive and adaptative behavior of wild rodents is synchronized primarily by the photoperiod. The viscacha, a South American rodent of nocturnal habits and seasonal reproduction is photoperiod‐dependent and its reproductive behavior is regulated by the retinohypothalamic‐pituitary pineal axis. Adult males exhibit an annual reproductive cycle with periods of maximum gonadal activity (summer‐early autumn) and gonadal regression (winter). The corpus and the cauda, the most sensitive segments of the epididymis to changes induced by the photoperiod, were analyzed using electron microscopy and enzymatic biochemistry. During gonadal regression, principal and clear cells showed signs of involution with respect to the activity period. These were characterized by more irregular nuclei, smaller cytoplasms, large vacuoles, altered mitochondria, and glycogen deposits. All cellular populations of the epididymal epithelium in regression presented abundant lysosome‐like dense bodies during the active period. In addition, we measured the activity of four acid glycosidases in the cauda epididymis along the reproductive cycle. N‐acetyl‐β‐D‐glucosaminidase (NAG), an enzyme that degrades endocytosed substances from the epididymal lumen, increased significantly during gonadal regression relative to the active period. These results demonstrate that the viscacha epididymis exhibits significant ultrastructural and biochemical changes during the reproductive cycle. We demonstrate that during regression, melatonin secretion in viscacha increases. This study shows that the epididymal epithelium is reduced. Thus, we postulate that the changes observed in the epididymis are modulated by pineal melatonin. Despite these changes, the epididymis might maintain a microenvironment suitable for the survival of stored spermatozoa. J. Morphol. 2009. © 2009 Wiley‐Liss, Inc.     

Loss of SED1/MFG‐E8 results in altered luminal physiology in the epididymis

SED1/MFG‐E8, herein referred to as SED1, is a bimotif adhesive protein with ascribed functions in a range of cell–cell interactions, including sperm‐egg binding. In the male reproductive tract, SED1 is secreted by the initial segment of the epididymis, where it coats sperm and subsequently facilitates binding to the egg zona pellucida. We have recently reported that SED1‐null epididymides show an unexpected incidence of spermatic granulomas, reflecting breakdown of the epithelium and a consequent autoimmune response against sperm antigens. However, spermatic granulomas are most often manifest in the distal segments of the epididymis, whereas the bulk of SED1 is expressed in the proximal epididymis. In some models, the presence of granulomas in the distal epididymis is associated with an underlying defect in the maintenance of luminal fluid homeostasis. Herein, we report that SED1‐null epididymal fluid is both hypo‐osmotic and alkaline, relative to wildtype epididymal fluid. Furthermore, the SED1‐null epididymal epithelium exhibits various hallmarks of disrupted fluid reabsorption and pH regulation, including altered morphology of clear cells, increased intracellular vesicles, and apical distribution of VATPase. Results indicate that the SED1‐null epididymal pathologies are not the secondary consequences of defective testes or efferent ducts or of improper epididymal differentiation, unlike that seen in other epididymal models. The expression and distribution of various ion exchangers, channels, and enzymes that mediate fluid transport and pH regulation are examined in wildtype and SED1‐null epididymides, and models to account for how SED1 functions in luminal fluid dynamics are discussed. Mol. Reprod. Dev. 77: 550–563, 2010. © 2010 Wiley‐Liss, Inc.     

Ultrastructure of langur monkey epididymidis prior to and following vasectomy and vasovasostomy.

The ultrastructural changes in langur monkey epididymis prior to and following vasectomy or vasovasostomy were studied. The epididymal epithelium of the intact langur monkey was found to consist mainly of principal cells and basal cells and frequently apical or mitochondria rich cells were found. Besides these cells intraepithelial lymphocytes were also a consistent feature of the epididymal epithelium. Principal cells identified by means of the tuft of the stereocilia on their apical surface, bear well developed Golgi bodies, endoplasmic reticulum, vesicles, vacuoles and multivesicular bodies. This suggests their active involvement in absorption and secretion. Basal cells present at the base of the lamina bear a few cellular organelles and strong interdigitations with the adjacent cells. Apical or mitochondria rich cells were characterized by clusters of mitochondria in the apical region of the cell and few microvilli on their apical surface. Lymphocytes with a large nucleus and a pale rim of cytoplasm were also found at the base of the epithelium. Secretory and absorptive functions of principal cells of the epididymal epithelium were found to be increased after vasectomy, as indicated by bulging of the apical portion of the principal cells and membrane bound structure in the lumen. An extensive increase in the number of lysosomes, vesicles and vacuoles was also observed. An increase in the number of macrophages with spermatozoa remnants in the lumen of epididymis suggests that the principal mechanism for spermatozoa disposal following vasectomy is intraluminal endocytosis by macrophages. Changes following vasectomy persisted in vasovasostomized animals even after 12 months of recanalization, which may contribute to the failure of functional reanastomosis.     

Testis morphology in rats chronically treated with letrozole, an aromatase inhibitor

The aim of this study was to investigate the influence of the long-term treatment of rats with letrozole on the testis morphology. The pharmacologically induced estrogen deficiency caused statistically significant decreases of both intratesticular and serum levels of estradiol, and morphological changes in the seminiferous epithelium and in the interstitial tissue of the testes. Six months of treatment resulted in the sloughing of premature germ cells of the seminiferous epithelium into the tubular lumen and in intraepithelial vacuolization. Multinucleated giant cells composed of premature germ cells, conglomerates of various cell nuclei and cell debris as well as irregularities and infoldings of the tubular basement membrane were also seen. Moreover, deep invaginations of the lamina propria with myoid cells were observed. Cells in the interstitial tissue showed changes similar to that observed in aging processes. The cytoplasm of LH-R-positive Leydig cells was loaded with lipofuscin granules. The number of lipofuscin-loaded cells was significantly increased in the interstitial tissue of testis in letrozole-treated rats. The results indicate the direct influence of estrogens on seminiferous tubules and the interstitial tissue morphology.