Effects of testosterone enanthate on the structure of the male reproductive tract of the rat

The histology and fine structure of the testis, epididymis and sex accessory glands were studied in young adult male rats administered testosterone enanthate, 120 μg/100 g body weight, three times weekly for 4, 8, or 12 weeks. The weights of the testis and epididymis decreased, and animals treated for 11 weeks were infertile. Alterations were found in the seminiferous tubules of all rats treated for 8 or 12 weeks, including the presence of many degenerating germ cells and a-large decrease or absence of late spermatids. Study of different stages of the cycle of the seminiferous epithelium showed that the greatest number of degenerating germ cells, step 7 spermatids and pachytene primary spermatocytes, occurred at stages VII-VIII of the cycle. Some normal appearing spermatogonia, primary spermatocytes and early spermatids remained in most seminiferous tubules. Sertoli cells contained many lipid droplets and lysosome-like bodies, and degenerating cells were surrounded by Ser-toli cell cytoplasm. The Leydig cells of treated animals were greatly reduced in size. Sperm progressively disappeared from the lumen of the middle segment and proximal part of the terminal segment of the epididymis after treatment for 8 or 12 weeks. Changes in the middle segment also included the appearance of intraepithelial cavities containing debris, and the presence within the epithelium of phagocytic cells that resembled leukocytes. The lumen of the proximal part of the terminal segment was often collapsed, while in the distal part of the terminal segment, the lumen was filled with cellular debris and degenerating sperm. Organelles of the principal cells of the epididymal epithelium appeared to be qualitatively unaltered. The weight of the sex accessory glands remained close to normal, and the presence of normal ultrastructural features suggested that production of secretions continued.     

Testicular development in cynomolgus monkeys

The testes from 136 male cynomolgus monkeys were examined histopathologically in order to investigate the relationship between the development of spermatogenesis and testis weight, age, and body weight. At Grade 1 (immature), Sertoli cells and spermatogonia were the only cell classes in the testis. At Grade 2 (pre-puberty), no elongated spermatids were observed in the testis, although a few round spermatids and small lumen formation were observed. At Grade 3 (onset of puberty), all classes of germ cells were observed in the testis, although seminiferous tubule diameters and numbers of germ cells were small. Slight debris in the epididymis was observed in almost all animals. At Grade 4 (puberty), almost complete spermatogenesis was observed in the seminiferous tubules and it was possible to ascertain the spermatogenesis stage as described by Clermont, although tubule diameters and numbers of germ cells were small. There was less debris in the epididymis than at Grade 3. At Grade 5 (early adult), complete spermatogenesis was observed in the seminiferous tubules. At Grade 6 (adult), complete spermatogenesis in the seminiferous tubules and a moderate or large number of sperm in the epididymis were observed. Moreover, sperm analysis using ejaculated sperm was possible. Logistic regression analysis showed that testis weight is a good indicator of testicular maturity.     

Germ cell transfer into rat, bovine, monkey and human testes.

Germ cell transplantation is a potentially valuable technique offering oncological patients gonadal protection by reinitiating spermatogenesis from stem cells which were reinfused into the seminiferous tubules. In order to achieve an intratubular germ cell transfer, intratubular microinjection, efferent duct injections and rete testis injections were applied on dissected testes of four different species: rat, bull, monkey and man. Ultrasound-guided intratesticular rete testis injection was the best and least invasive injection technique with maximal infusion efficiency for larger testes. Deep infiltration of seminiferous tubules was only achieved in immature or partially regressed testes. This technique was applied in vivo on two cynomolgus monkeys. In the first monkey a deep infusion of injected cells and dye into the lumen of the seminiferous tubules was achieved. In the second, transplanted germ cells were present in the seminiferous epithelium 4 weeks after the transfer. These cells were morphologically identified as B-spermatogonia and located at the base of the seminiferous epithelium. In summary, this paper describes a promising approach for germ cell infusion into large testes. The application of this technique is the first successful attempt of a germ cell transfer in a primate.     

Early testicular changes after vasectomy and vasovasostomy in Lewis rats

The testes of Lewis rats were studied at intervals from 2 weeks to 3 months after bilateral vasectomy, vasectomy followed 1 month later by vasovasostomy, or sham operations. Aims were to determine the nature of early alterations after vasectomy, and to determine whether vasovasostomy after 1 month would result in reversal of vasectomy-induced changes. Approximately one-fourth of the testes in the vasectomy and vasovasostomy groups displayed histological changes, which consisted mainly of depletion of germ cells. The extent of the depletion varied greatly in different seminiferous tubules. In testes altered in this way, no abnormal infiltrations of lymphocytes, macrophages, or other cells were observed in the seminiferous epithelium or in the interstitium. The rete testis and straight tubules were normal in testes with altered seminiferous epithelium. A few testes in the vasectomy and vasovasostomy groups had necrotic centers. The results suggest that depletion of germ cells occurred as a result of shedding from the seminiferous epithelium into the lumen of the tubules. A cellular immune response, such as occurs in experimental allergic orchitis in other species, did not appear to be responsible for the observed loss of germ cells. This suggests a possible role for humoral antibody in this model, since there is an association between testicular changes and serum antisperm antibodies at longer intervals after vasectomy. Testicular alterations were not reversed by performance of a vasovasostomy 1 month after vasectomy.     

The Human Blood-Testis Barrier in Impaired Spermatogenesis

The aim of this study was to explore the competence of the blood-testis barrier (BTB) using electron opaque tracers in diverse human testicular pathologies associated with Sertoli cell only syndrome. Two groups of patients were studied: (1) those with complete depletion (absence) of germ cells, and (2) those with severe germ cell depletion but with some germ cells left in the seminiferous epithelium. The first situation was associated with cryptorchidism with absence of germinal cells, idiopathic cases of aplasia of germ cells, peritumoral areas surrounding small seminomas where the seminiferous tubules were observed to contain a predominant population of Sertoli cells, or long estrogen treatment. The second was found also in cryptorchidism with early germ cells, idiopathic azoospermia, and oligospermia associated with sterility. In the first situation, seminiferous tubules lacked lumen and Sertoli cells had immature morphological characteristics, i.e., oval nuclei with smooth profiles, even heterochromatin distribution and a single, small nucleolus. Inter-Sertoli tight junctions were tortuous, interrupted, and mostly perpendicular to the basal lamina. Lanthanum hydroxide or nickel nitrate permeated most of the inter-Sertoli spaces, indicating disruption of the BTB. In the second situation, seminiferous tubules had a lumen, and Sertoli cells exhibited a mature appearance with large tripartite nucleoli and irregular, highly infolded nucleo-lemma. Only spermatogonia or primary spermatocytes showing diverse degrees of cell involution were found. Numerous inter-Sertoli tight junctions, uninterrupted and parallel to the basal lamina, stopped the electron opaque intercellular tracers close to it; this meant the assembly of a competent BTB. Therefore, a close correlation was found between morphological parameters of Sertoli cell maturity, including their tight junction organization, and BTB integrity.     

Macro-orchidism: light and electron microscopic study of four cases.

A hormonal and quantitative light microscopy study of one man with macro-orchidism associated with mental retardation and fragile X chromosome (case no. 1) and three men with idiopathic macro-orchidism (cases no. 2 to 4) is reported. Hormonal study revealed slightly increased follicle-stimulating hormone serum levels in cases no. 1 to 3. The testes from cases no. 1 (orchidoepididymoectomy specimen) and 2 (testicular biopsy) presented interstitial edema and three different tubular patterns that were arranged in a mosaic-like manner. Type I tubules had an increased diameter (less than 220 microns), dilated lumen, and thin seminiferous epithelium usually consisting of Sertoli cells, spermatogonia, primary spermatocytes, and sometimes a few spermatids. Type II tubules had a normal diameter (180 to 220 microns) and germ cell development varied between complete spermatogenesis and Sertoli-cell-only tubules. Type III tubules had decreased diameter (less than 180 microns), atrophic seminiferous epithelium, and thickened tunica propria. The appearance of the nuclei of the Sertoli cells in the three types of tubules could be either mature or immature. Some of the mature Sertoli cells presented a granular cytoplasm. A few of these granular cells grouped together, forming nests that protruded into the tubular lumen. The testicular biopsies from cases no. 3 and 4 only presented type II tubules that contained both mature and immature Sertoli cells. Quantitative study revealed that the large testicular size was principally due to an increased tubular length in all four cases. Although the seminiferous tubule lesions and interstitial edema suggest an obstructive process, the testicular excretory ducts (studied in case no. 1) appeared normal or only slightly dilated. It is possible that the seminiferous tubule lesions (dilated lumen and germ cell depletion) might be secondary to the Sertoli cell lesions (granular cytoplasm and nuclear immature-like pattern.     

Induction of experimental autoimmune orchitis in guinea pigs after ligation of the seminiferous ducts

In 18 immature guinea pigs both sides of the vasa efferentia were ligated; 18 control animals were not altered. The ligation did not prevent the formation in mature animals of active spermatogenesis in the majority of seminiferous tubules, but did cause a reduction in the number of layers of seminiferous epithelium in some, and atrophy of the epididymis due to the absence of germ cells. Immunization, in the adult stage, with homogenate of homologous testis mixed with complete Freund adjuvant created changes in the permeability of the blood-testis barrier in relation to endogenous globulins and rivanol and the development of autoimmune orchitis of the same intensity and terms as in the control animals. In contrast to the control group, destructive changes in the testis did not follow with inflammatory processes in the epididymis.     

Effects of respiratory treatment with N-hexane on rat testis morphology. I. A light microscopic study

Testicular damage was induced in rats by respiratory treatment with n-hexane at a concentration of 5000 ppm. The earliest lesions were observed immediately after 24 hr of continuous treatment, and involved primary spermatocytes from the leptotene to the middle pachitene stages and spermatids at late stages of maturation; at the same time numerous exfoliated, injured germ cells reached the epididymis. After the 24-hr treatment was suspended, damage to the seminiferous epithelium increased for the first 7 days, while the epididymis showed also focal infiltration by inflammatory cells; recovery was completed from Days 14 to 30. Intermittent treatment (16 hr/day, 6 days/week) at the same concentration of 5000 ppm for up to 6 weeks induced progressive increases in testicular and epididymal lesions, which, after 5 weeks (when most animals began to show clinical symptoms of polyneuropathy), reached aplasia of the germinal epithelium involving also the spermatogonia. Recovery from clinical symptoms was not paralleled by a regression of testicular pathology. On the contrary, after interruption of the treatment, the testicular lesions became increasingly severe, up to complete atrophy of the seminiferous tubules, suggesting an irreversible sterility of the treated animals. Pair-fed controls did not show histological alterations of the testis or epididymis.     

Orchitis and human immunodeficiency virus type 1 infected cells in reproductive tissues from men with the acquired immune deficiency syndrome.

Mechanisms underlying human immunodeficiency virus type 1 (HIV-1) infection of the male reproductive tract and the sexual transmission of HIV-1 through semen are poorly understood. To address these issues, the authors performed morphologic and immunocytochemical analyses of reproductive tissues obtained at autopsy from 43 male acquired immune deficiency syndrome (AIDS) patients. Monoclonal antibodies recognizing different subpopulations of white blood cells were used to detect leukocyte infiltration and map the location of potential lymphocytic/monocytic HIV-1 host cells and immunocytochemistry and in situ hybridization techniques were used to detect HIV-1-infected cells in the testis, excurrent ducts, and prostate. Distinct pathologic changes were observed in a majority of testes of AIDS patients that included azoospermia, hyalinization of the boundary wall of seminiferous tubules, and lymphocytic infiltration of the interstitium. The reproductive excurrent ducts and prostate appeared morphologically normal except for the presence of focal accumulations of white blood cells in the connective tissue stroma. In the testis many white blood cells were shown to be CD4+, indicating the presence of abundant host cells (T-helper/inducer lymphocytes and macrophages) for HIV-1. Furthermore macrophages and cells of lymphocytic morphology were observed migrating across the boundary walls of hyalinized seminiferous in tubules to enter the lumen. In 9 of the 23 cases tested for HIV-1 protein expression by immunocytochemistry. HIV-1 + cells of lymphocytic/monocytic morphology were found in the seminiferous tubules and interstitium of the testis, epididymal epithelium, and connective tissue of the epididymis and prostate. One patient with epididymal blockage had accumulations of HIV-1-antigen-positive cells of macrophages morphology in the distended lumen of the efferent ducts. There was no evidence of active HIV-1 infection in germ cells or Sertoli cells of the seminiferous tubules or other epithelial cells lining the excurrent ducts or prostatic glands.     

Fine structure of the testis and epididymis of rats treated with cyproterone acetate

Adult male rats were administered the antiandrogen, cyproterone acetate, for 4, 8 or 12 weeks, and the histology and fine structure of the testis and several parts of the epididymis were studied. After treatment for 8 or 12 weeks, the testes of treated animals displayed a great reduction in the abundance of late spermatids. Necrotic cells, many of which were identified as cap-phase spermatids, were present in the seminiferous epithelium. Sertoli cells contained many large lipid droplets and lysosome-like structures with a content of cellular debris, including parts of spermatids. Leydig cells of treated rats were smaller than those of control animals at all the intervals studied. Sperm were absent from the lumen of the middle segment, or caput epididymidis, of severely affected specimens. In the terminal segment, or cauda epididymidis, the microscopic appearance varied in different regions. In the proximal part of the cauda epididymidis, the lumen was usually clear of sperm. The epithelium was tall and the light cells were very large and distended with many dense bodies resembling lysosomes. In contrast, in the distal part of the cauda epididymidis, the lumen was filled with sperm and debris, which appeared to be derived from germ cells. It is suggested that the light cells of the epididymal epithelium may have a role in clearing the lumen in the proximal part of the cauda epididymidis, in which they are particularly large and numerous. The results suggest that in the presence of cyproterone acetate, germ cells develop up to cap-phase spermatids and then begin to undergo degeneration and death. This alteration may have an important role in the antifertility effect of the drug, but changes in the epididymis may contribute also.     

Toxic effects of anatoxin-a on testes and sperm counts of male mice

Anatoxin-a, a potent neurotoxin, is one of a number of toxins produced by cyanobacteria especially some strains of Anabaena. Toxic cyanobacteria are found worldwide in inland and coastal water environments. The present study was performed to evaluate the toxicity of anatoxin-a on testes and sperm counts of male mice. The animals of the treatment groups were administered with 50, 100 and 150microg/kg/day anatoxin-a for seven consecutive days by intraperitoneal (i.p.) route. Although there were no significant changes in body weight gain, and absolute and relative testes weights, absolute and relative weights of cauda epididymis reduced significantly in the 100 and 150microg/kg groups when compared with control group. The number of sperm count in cauda epididymis was reduced dose dependently in all treatment groups compared with control animals. Anatoxin-a caused dose-dependent histopathological changes in the testes of mice such as degenerations in seminiferous tubules, intercellular disassociation of spermatogenetic cell lines, sloughing of germ cells into tubular lumen, vacuolisation in Sertoli cells and loss of germ cells. The epithelial thickness of seminiferous tubules decreased significantly in all treatment groups in a dose-dependent manner.     

Focal orchitis in undescended testes: discussion of pathogenetic mechanisms of tubular atrophy.

OBJECTIVE: To evaluate seminiferous epithelium lesions in adult cryptorchid testes showing lymphoid infiltrates in seminiferous tubules and interstitium (i.e., focal orchitis). Also, to consider the possible role of this lesion in the etiology of tubular atrophy. METHODS: We performed a histopathologic study of the cryptorchid testes and adjacent epididymides removed from 50 adult men who had not been previously treated for cryptorchidism. The study included morphologic and semiquantitative evaluation of seminiferous tubule pathology (according to germ cell numbers), Sertoli cell morphology, tubular lumen dilation, rete testis pattern (normal, hypoplastic, or cystic), and epididymal pattern (normal or epididymal duct hypoplasia). The study also included immunohistochemical evaluation of immune cell markers. The results were compared with clinical and laboratory findings. RESULTS: Focal lymphoid infiltrates (mainly lymphocytes) in seminiferous tubules and interstitium were found in 22 patients (44%), all of whom had unilateral cryptorchidism. The course of orchitis was asymptomatic, and laboratory data were normal. According to the seminiferous tubule pathology, a variety of histopathologic diagnoses, were made: (1) mixed atrophy consisting of Sertoli cell-only tubules intermingled with tubules showing maturation arrest of spermatogonia (11 testes, 4 of which also showed hyalinized tubules); (2) Sertoli cell-only tubules plus hyalinized tubules (4 testes); (3) Sertoli cell-only tubules (3 testes); (4) intratubular germ cell neoplasia (2 testes, 1 of which also showed hyalinized tubules); (5) complete tubular hyalinization (1 testis); and (6) tubular hyalinization plus some groups of tubules with hypospermatogenesis (all germ cell types were present although in lower numbers, 1 testis). Dysgenetic Sertoli cells, that is, Sertoli cells that had undergone anomalous, incomplete maturation, were observed in all nonhyalinized seminiferous tubules with inflammatory infiltrates. Tubular ectasia was observed in 13 cases. The rete testis was hypoplastic and showed cystic transformation in 18 testes, and the epididymis was hypoplastic in 15 testes. CONCLUSIONS: The causes of these focal inflammatory infiltrates are unknown. It is possible that tubular ectasia and Sertoli cell dysgenesis are involved and that these alterations cause a disruption of the blood-testis barrier and allow antigens to enter the testicular interstitium, giving rise to an autoimmune process.     

Seasonal changes in spermatogenesis of the Japanese lesser horseshoe bat,Rhinolophus cornutus from a morphological viewpoint

Seasonal changes in spermatogenesis of Japanese lesser horseshoe bats, Rhinolophus cornutus, captured in Aomori Prefecture (Japan) were examined by light microscopy. In March, the seminiferous tubules revealed almost no lumen. The seminiferous epithelium consisted of Sertoli cells and spermatogonia. The interstitium occupied a relatively large area. In June, the seminiferous tubules gradually increased in diameter. Lumen was clearly seen at the center of seminiferous tubules. Mitotic figures of spermatogonia and spermatocytes were occasionally recognized. Interstitium occupation was still abundant. In August, the diameter of seminiferous tubules maximized. The interstitium occupied only a small area. Active spermatogenesis was obvious at this time. Released spermatozoa were frequently observed within the expanded lumen. In October, although spermatogenesis was still active, the diameter of seminiferous tubules tended to decrease in size. In December, active spermatogenesis completely disappeared. The diameter of tubules greatly decreased. In most cases, the seminiferous epithelium contained only Sertoli cells and spermatogonia. Thus, spermatogenesis in Japanese lesser horseshoe bats occurs from the middle or late summer to the middle autumn in Aomori Prefecture. In epididymal tracts, aggregated spermatozoa were recognized throughout the year. The cytoplasm of all Leydig cells in the interstitium was positive for 3beta-hydroxysteroid dehydrogenase throughout the year.     

Organization of tubules in the human caput epididymidis and the ultrastructure of their epithelia

The structure of the human caput epididymidis was examined by gross morphological and light and electron microscopic techniques. There were at least seven types of tubules, each characterized by a different epithelium. These tubules were connected with one another by at least eight types of junctions to form a network. Most of the caput epididymidis was composed of efferent ducts. Within these, five types of tubules, each with a different ciliated epithelium, were found in different regions; and four types of junctions between the efferent ducts and the epididymal tubule were observed. The efferent ducts left the testis, initially as parallel straight tubules containing both ciliated and non-ciliated cells in an epithelium of irregular height. Each efferent duct then coiled tortuously into lobules that folded over one another. These efferent ducts then branched out as thin tubules to join a network of dark tubules which were lined by a regular epithelium containing prominently vacuolated, nonciliated cells. These tubules anastomosed via common cavities characterized by a ciliated cuboidal epithelium and sometimes joined tubules exhibiting a non-vacuolated ciliated epithelium. The latter, as well as typical efferent ducts, made connection with the epididymis proper in both end-to-end and end-to-side junctions. In the more distal junctions with the epididymis, the efferent ducts joined to a transitional epididymal ductule before joining to the side of the epididymis proper. Post-junctional epithelia in the beginning of the epididymis occasionally contained patches of cells characteristic of efferent ducts. Tall cells with long stereocilia constituted a discontinuous “initial segment”-like region of the epididymis. This is the most detailed study so far of the epithelia and the tubule organization in the caput epididymidis of any species, and most of the results are reported for the first time for the human. Although the pattern of the tubule network resembles that of some domestic species, the rich variety of epithelia has not been appreciated before.     

Reproduction in male swamp wallabies (Wallabia bicolor): puberty and the effects of season

This study describes pubertal changes in testes and epididymides and seasonal changes in the adult male reproductive organs and plasma androgen concentrations of the swamp wallaby (Wallabia bicolor). Pre-pubescent males had testes with solid seminiferous cords and spermatogenesis only to the stage of gonocytes. Their epididymides had empty lumina along their entire length. The testes of three males undergoing puberty had some lumen formation and mitotic activity. Their epididymides were similar in appearance to those of adult males but were entirely devoid of any cells within the lumen of the duct. Three other pubescent males showed full lumen formation in the testes and spermatogenesis up to the elongating spermatid stage. Their epididymides were similar in appearance to those of adult males but with no spermatozoa in the duct. However, cells of testicular origin were found in the lumen of the duct in all regions suggesting that testicular fluids and immature germ cells shed into the rete testes flow through the seminiferous tubules into the epididymis before the release of mature testicular spermatozoa. The weights of testes and epididymides of adult males showed no change throughout the year but prostate weight and plasma androgen concentrations varied significantly with season, with maximums in spring and summer and minimums in winter. The volume fraction of Leydig cells and seminiferous tubules was significantly lower in winter than in summer; but, despite this, maturing spermatozoa were found in the testes throughout the year. Females in the area conceived year-round, suggesting that seasonal changes in the male reproductive tract did not prevent at least some males from breeding throughout the year.     

Permeability of the diaphragmatic mesothelium: The ultrastructural basis for “stomata”

The ultrastructure of the hamster efferent ducts and epididymis was studied and the results were correlated with previously published data on the composition of luminal fluid obtained by micropuncture. Samples of the efferent ducts and parts of the epididymis designated initial segment, caput, corpus, proximal cauda, distal cauda, and “epididymal vas” were prepared. The efferent ducts contained principal cells characterized by a profusion of apical vesicles and numerous very large vacuoles that were distributed throughout the cytoplasm. Ciliated cells had few vesicles and vacuoles. Occasional cells contained many particles resembling glycogen. In the epididymis, the following trends were observed. The height of the epithelium and the size of the principal cells declined from initial segment to distal cauda. Apical vesicles and vacuoles with a light content were extremely numerous in principal cells of the initial segment and decreased progressively in the more distal regions. In the initial segment, basal and perinuclear rough endoplasmic reticulum was abundant and was distended with a material that resembled newly synthesized protein. Further distally in the epididymis cisternae of the rough endoplasmic reticulum were narrow and contained little intracisternal material. Light cells containing many vesicles, vacuoles, and lysosome-like structures were very prominent in the caudal segments. The epithelium of the epididymal vas had features intermediate between cauda epididymidis and ductus deferens. The cytoplasmic droplet in luminal sperm began to migrate caudally between the caput and corpus epididymidis and reached the posterior extremity of the middle piece in the distal cauda. Some degenerating sperm were observed in the lumen of the distal segments of the epididymis. The abundance of cytoplasmic vesicles and vacuoles in principal cells of the efferent ducts and initial segment of the epididymis correlated with the site of greatest fluid absorption as determined by micropuncture studies, suggesting that these structures are involved in absorption of fluid from the lumen. Between the caput and distal cauda epididymal segments, where absorption of sodium and potassium but not of fluid occurred, there were few vesicles and vacuoles in principal cells, but the “light” cells were large and numerous and contained many vacuoles. The principal cells of the initial segment were best equipped with rough endoplasmic reticulum to synthesize a protein.     

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.     

Deleterious effects of Pfaffia glomerata (Spreng.) Pedersen hydroalcoholic extract on the seminiferous epithelium of adult Balb/c mice

Several plant species such as Pfaffia glomerata are widely used in traditional Brazilian medicine as stimulants and aphrodisiacs. In this regard, the aim of our study was to explore the effects of the long‐term intake of the hydro‐alcoholic root extract of P glomerata on the germ and somatic cells within the seminiferous tubules in adult Balb/c mice. The experimental groups were placed as: controls (water and DMSO), and treated with 300 and 400 mg/kg of the root extract. The number of germ and somatic cells, the proportion of pathological seminiferous tubules, and the germ cell apoptotic levels were evaluated. The volume and proportion of the seminiferous epithelium was decreased after the extract intake due to the increased germ cell apoptotic levels. Vacuolization of Sertoli cell cytoplasm was observed widely in pathological tubules, along with fully disorganized epithelia, showing multinucleated cells, which lead to decreased daily sperm production. Taken together, our results indicate that long‐term intake of the P glomerata caused deleterious effects on spermatogenesis by inducing apoptosis and altering the seminiferous tubule's epithelial dynamics.     

Proliferation and apoptosis of spermatogonia in postpuberal boar (Sus domesticus) testes with spontaneous unilateral and bilateral abdominal cryptorchidism

Cryptorchidism is a frequent male sexual disorder in mammals, which affects the histology of the tunica propria, interstitial tissue, blood vessels, seminiferous epithelium and testis functioning. In this paper, proliferation and apoptosis were examined in the seminiferous epithelium of both testes from unaffected boars and from boars suffering unilateral and bilateral cryptorchidism. In germ cells, proliferation was studied using the immunohistochemical PCNA technique, and apoptosis was analysed by in situ TUNEL labelling. An index was obtained for the proliferation and apoptosis observed in seminiferous tubules. In abdominal testes the epithelium contained few spermatogonia and Sertoli cells. In the testes of unaffected boars, numerous spermatogonia proliferated, whereas in cryptorchid testes such proliferation was lower and the proliferation/apoptosis ratio diminished. In the unaffected group, the TUNEL-positive germ cells were spermatogonia and spermatocytes in different phases of meiosis. In abdominal testes, the TUNEL-positive germ cells were spermatogonia alone. The apoptosis index of both abdominal and scrotal testes was similar. In conclusion, spontaneous cryptorchid testes showed a lower rate of spermatogonia proliferation in the seminiferous epithelium.     

Morphologic evaluation of the effect of long-term administration of ammonium fluoride on the seminiferous epithelium and epididymis in the rat

Male rats were subjected to 9-month-long exposure to ammonium fluoride. The performed evaluation covered the seminiferous epithelium and epididymis. The greatest changes in animals used in the experiment were observed in epididymis. A small number of spermatozoa were seen in the lumen of ductus epididymis, while in the epithelial cells there were increased phagocytic processes, providing a proof that injured reproductive cells were eliminated from the genital tract.