Degenerated tubules in the guinea pig testis after long-term vasectomy or sham operation

The testes of eight unilaterally vasectomized and six sham-operated Dunkin Hartley guinea pigs were examined 3 years after operation by wax and resin histology and transmission electron microscopy. Degenerated tubules are reported that were common on the side of vasectomy but also found in the contralateral testes and in the controls. A central accumulation of macrophages, rich in phagocytosed debris including spermatozoal fragments, was surrounded by attenuated Sertoli cells, a markedly thickened basement membrane and myoid cells. At some sites macrophages impinged directly on the basement membrane. They probably represented highly degenerated seminiferous tubules. The study suggests that the response to injury of seminiferous tubules may show species variations. Macrophages did not feature in the degenerated seminiferous tubules we reported following vasectomy in the rat. However, the rat showed striking changes in the morphology of the basal laminae and myoid cells which did not occur in the guinea pig. Pathological changes have been reported in the human testis following vasectomy but their etiology is unclear. Studies in the guinea pig are enhancing understanding of the mechanisms and features of testicular damage.     

Testicular involution after optic enucleation: Ultrastructure and alkaline phosphatase cytochemistry of the peritubular tissue

Two months after blinding hamsters, the seminiferous epithelium had undergone pronounced involution. Spermatogonia were the only germ cells consistently present in the seminiferous tubules, although some tubules also contained primary spermatocytes. The peritubular tissue in the blinded hamster had undergone marked distortion. Irregular projections extended from the myoid cells and protruded toward the seminiferous epithelium. All layers of the peritubular tissue developed irregular contours and underwent thickening. The myoid cell nuclei were highly infolded, giving the nucleus a lobulated appearance. Golgi stacks often occupied recesses in the cytoplasm created by nuclear folding. Numerous vesicles were located at the poles of the Golgi stacks and were scattered between the Golgi stacks and the plasmalemma. Vesicles were also observed fusing with the plasmalemma. Alkaline phosphatase was localized cytochemically in the Golgi apparatus and the myoid cell vesicles. The appearance of the myoid cells in the involuting testes was similar to that of contracting smooth muscle; therefore, we postulate that the cytological alterations observed in the myoid cells may be a result of myoid cell contractions. Myoid cell vesicles have previously been thought to selectively take up substances at the interstitial surface of the myoid cell, transport the material across the cytoplasm and release their contents at the surface adjacent to the seminiferous epithelium. The findings reported in the present investigation indicate that some of these vesicles are involved in exocytosis of substances synthesized in the myoid cell. It appears that myoid cell exocytosis may be involved in formation of the alkaline phosphataserich basal laminae of the peritubular tissue.     

Light cells within the limiting membrane of rat seminiferous tubules

Light-staining cells, distinct from myoid cells, were identified in electron micrographs of the limiting membrane of rat seminiferous tubules. While these cells were also found free in the interstitial space, they were observed mostly in the myoid cell layer of the limiting membrane but were never seen within the seminiferous epithelium itself. The light cells were characterized by a pale-stained cytoplasm containing a spheroidal Golgi apparatus next to a polymorphous often kidney-shaped nucleus, a few cisternae of rough endoplasmic reticulum and some granules of various types including multivesicular bodies. In hematoxylin-stained whole mounts of dissected tubules, these light cells were readily identified under the light microscope by nuclear morphology and light-staining juxtanuclear Golgi apparatus. The incidence of these cells, per unit surface area of tubular wall, was calculated, taking into consideration the stages of the cycle of the seminiferous epithelium with which they were associated. Distributed along the entire length of seminiferous tubules, their number varied significantly during the cycle. Low numbers were found in stages II–IV and XIII of the cycle, while high numbers were found in stages IX to XII and XIV–I of the cycle. These observations indicate that the seminiferous epithelium may exert an influence on the population of light cells present in the tubular limiting membrane.     

Morphological and histochemical characteristics of the lamina propria in scrotal and abdominal testes from postpubertal boars: correlation with the appearance of the seminiferous epithelium

This study was undertaken to investigate the morphological characteristics and lectin affinity of the testicular lamina propria in healthy boars and in unilateral and bilateral abdominal cryptorchid boars. The lamina propria of scrotal testes from healthy boars and unilateral cryptorchid boars was constituted by an innermost noncellular layer, the basal lamina, and by 2 layers of peritubular cells, each separated by a fibrous layer. The noncellular layers contained collagen fibres and glycoconjugates with abundant N‐acetylgalactosamine, galactose, fucose, N‐acetylglucosamine and neuraminic acid residues. The inner peritubular cell layer was composed of myoid cells, the outer layer of fibroblasts. In the abdominal testes of unilateral and bilateral cryptorchid boars, the lamina propria of nondegenerating and degenerating seminiferous tubules appeared thickened due to an increased content of collagen fibres and glycoconjugates. Glycoconjugates showed decreased amounts of fucose, neuraminic acid and galactose, and increased amounts of N‐acetylglucosamine residues. The basal lamina formed infoldings toward the seminiferous epithelium and contained small cells. Both inner and outer peritubular cells were fibroblasts of immature appearance. In degenerated seminiferous tubules of bilateral cryptorchid boars, the lamina propria was composed of a thickened and collagenised basal lamina, without peritubular cells and with a low content of glycoconjugates. In scrotal testes, therefore, the lamina propria was implicated in tubular contractility and in mediating the communication and the substrate diffusion between seminiferous tubules and interstitial tissue. Cryptorchidism induced morphological and histochemical alterations in the lamina propria of abdominal testes, which may be linked to evidence from other studies of lack of tubular contractility and defective cell–cell communication and substrate diffusion. The severity of these anomalies correlated with the severity of Sertoli cell alterations.     

Fine structure of boundary tissue of the seminiferous tubules in the scrotal and abdominal testes of naturally unilateral cryptorchid West African dwarf goats

The boundary tissue of the seminiferous tubules in the scrotal and abdominal testes of naturally unilateral cryptorchid West African dwarf goats comprised an inner non-cellular, a middle cellular and peripheral cellular lamellae. In the scrotal testes, these components were compact and their arrangement conformed to that described for other domestic ruminants except that here, the basal lamina associated with the seminiferous epithelium was homogeneous and in tact. Alterations due to cryptorchidism as observed in the contralateral abdominal testes include general loss of compactness due to depletion and disorganization of structural extracellular materials like basal lamina coat of myoid cells and collagen fibrils, the splitting of the basal lamina of the seminiferous epithelium into 8-12 thin layers, poor differentiation of the myoid cells and the accumulation of lipid droplets within their cytoplasm. It is concluded that the normal caprine boundary tissue conforms entirely to the characteristics of 'Type C' category in the existing classification. The ultrastructural alterations due to abdominal retention of the testis resemble the testicular changes ascribed to the disturbance of pituitary-testicular hormonal axis.     

Immunological and morphological effects of vasectomy in the rabbit

Half of the rabbits developed antisperm antibodies (measured by either indirect immunofluorescence or sperm immobilization tests) after either a unilateral or bilateral vasectomy. The raised antibody levels, particularly six months or longer after vasectomy, often accompanied patchy orchitis. Seminiferous tubules from such animals exhibited sloughed, multinucleated, and immature germinal cells which were engulfed by phagocytic cells. Mononuclear infiltrates were occasionally present. The basal lamina infolded and thickened by means of supernumerary layers and appeared to be endocytosed by cells of the seminiferous tubules. Four months after vasectomy, numerous phagocytic cells were seen to migrate through the intact epithelium of zone 1 in the caput epididymidis, and were particularly prevalent in animals that exhibited testicular damage. These macrophages may serve to present sperm antigens to lymphocytes.     

Changes in the arrangement of actin filaments in myoid cells and sertoli cells of rat testes during postnatal development and after experimental cryptorchidism

Background: Abundant actin filaments are present in myoid cells and Sertoli cells in the testis. In the adult rat, the filaments form a lattice arrangement within the myoid cell, and show a hexagonal pattern in the basal junctional regions of Sertoli cells. Methods: Isolated seminiferous tubules and frozen sections were prepared from juvenile to adult Wistar rat testes, stained with FITC-conjugated phalloidin, and observed by confocal microscopy. Unilateral cryptorchidism was induced in adult rats, and seven days later, their testes were also examined. Results: In the myoid cell, parallel actin filaments running circularly around the seminiferous tubules were observed at 15 and 20 days of age. Then, at 30 days, actin filaments arranged longitudinally along the tubular long axis appeared in addition to the circular bundles. A lattice arrangement of actin-filament bundles in myoid cells became obvious at 40 days, when elongated spermatids are found in the tubule. Actin filaments in the basal junctional regions of Sertoli cells did not acquire the hexagonal pattern seen in the adult testis until 30 days of age. In the cryptorchid testes, the arrangement of actin filaments in the both cells showed a remarkable change compared to the control testis; the filaments became thinner and disrupted. Conclusions: A lattice arrangement of the actin filaments in the myoid cell appear at around 30 days, before the completion of spermatogenesis. A hexagonal pattern of the filaments in the junctional regions of Sertoli cells has already developed at this age. Cryptorchidism affects the actin filaments of the both cells. © 1995 Wiley-Liss, Inc.     

Effect of long‐term vasectomy on seminiferous tubules in the guinea pig

The little previous work on the influence of vasectomy on the guinea pig testis has given controversial results. One group reports that the guinea pig suffers autoimmune orchitis while others claim damage may be mechanical. To clarify the issue, this study compares the morphology of seminiferous tubules 3 years after left unilateral vasectomy (8 guinea pigs) and control sham operation (6 animals). Grossly, left and right testes following left‐sided vasectomy were similar to controls and not significantly different in weight. On histology, left and right experimental testes and the control material showed various degrees of seminiferous tubular degeneration, including intraepithelial vesicle formation, loss of germ cells and intraluminal macrophages. Although vesicle formation was striking in most testes, quantitative analysis indicated that it was more frequent in the ipsilateral testis following unilateral vasectomy. It seems that vasectomy had exacerbated an age‐related phenomenon. Lymphocytic infiltration was seen in five of the left testes following vasectomy, in two of the corresponding right testes, but in none of the controls. Two vasectomized left testes, however, showed atrophic changes but no lymphocytic invasion. The results suggest that autoimmune orchitis follows vasectomy but that it may not be the primary cause of degeneration. Attempts to gain positive evidence for mechanical damage, however, were inconclusive. Clin. Anat. 12:250–263, 1999. © 1999 Wiley‐Liss, Inc.     

Leydig cells within the aspermatogenic seminiferous tubules

Cells identical to Leydig cells were found within a peritubular boundary layer and even inside a basal lamina of seminiferous tubules in three male patients (two with inguinal cryptorchism and one with infertility). The seminiferous tubules of all patients showed a moderate to marked thickening of the boundary layer and a complete loss of spermatogenic cells. The "ectopic Leydig cells" were characterized by the presence of Reinke crystals or an extensively developed smooth endoplasmic reticulum. These cells were believed to have differentiated in situ from myoid cells within the boundary layer and also to have invaded from the interstitial tissue in the form of mature Leydig cells. The occurrence of ectopic Leydig cells appeared to parallel the extent of loss of the Sertoli cells and also that of the thickening of the boundary layer. The functional significance of the ectopic occurrence might be implicated in the impaired spermatogenesis.     

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.     

A fine-structural study of interstitial cell changes in the testes of Necturus maculosus during a portion of the annual cycle,and possible evidence for local feedback control by seminiferous epithelium

The developmental stages of the interstitial cells of Leydig in Necturus maculosus were studied in testes of animals obtained in November and December. As a consequence of the caudal to cranial progression of the wave of spermatogenesis, samples obtained from cranial, central, and caudal portions of these testes exhibit regional differences in the morphology of their Leydig cells. In these samples, fibroblast-like stromal cells with large, dense, elongated nuclei and thin sheets of cytoplasm surround the cranial seminiferous lobules that usually contain spermatozoa. Such stromal cells possess a small juxtanuclear Golgi apparatus, profiles of smooth and rough endoplasmic reticulum, and mitochondria with tubular and shelf-like cristae. In the central area of the testis, interstitial cells with oval nuclear profiles and a finer chromatin pattern surround degenerating seminiferous lobules. The abundant cytoplasm of these cells contains predominantly smooth endoplasmic reticulum interspersed with a few lipid droplets. These cells contain mitochondria that are packed with tubular cristae. In the caudal part of the testis, the Leydig cells have a round nucleus with finely dispersed chromatin. Numerous lipid droplets accumulate in the ample cytoplasm, which is filled with smooth endoplasmic reticulum. The juxtanuclear Golgi apparatus becomes enlarged; associated with it are vesicles with an electron-dense content. The cristae of the mitochondria are more numerous and have tubules of 50-nm diameter mixed with arrays of small tubules 25–30 nm in diameter. The appearance of morphologically mature interstitial cells of Leydig only adjacent to degenerated seminiferous lobules in the caudal portion of the testis suggests the possibility of local feedback control of Leydig-cell development.     

Spermatogenesis in the vasectomized monkey: Quantitative analysis

The seminiferous epithelium in mature vasectomized Macaca fascicularis was examined quantitatively to assess spermatogenesis. Monkeys were bilaterally vasectomized and controls were bilaterally sham operated. At postoperative periods of 10 and 18 months, groups of monkeys were castrated and their testes prepared for morphologic analysis. Diameters were measured in 100 cross sections of seminiferous tubules from each animal. Numbers of spermatogonia (Ad and Ap), preleptotene spermatocytes, pachytene spermatocytes, and step 7 spermatids, relative to Sertoli cell nucleoli, were counted in stage VII tubules. Tubule diameter and germ cell numbers per Sertoli cell nucleoli were not altered by vasectomy. Our study demonstrates quantitatively that spermatogenesis in the monkey is not inhibited up to 18 months following vasectomy.     

Morphological aspects of cultured rat seminiferous tubules in the presence of fetal calf serum and follicle-stimulating hormone

Culturing seminiferous tubules allows the analysis of spermatogenesis under controlled conditions. Reproducing the specific microenvironment for germ cells is a challenge taken up by various studies. The difficulty in supplementing all nutrients and the physical disturbances during isolation procedures cause degeneration of many cells in the seminiferous epithelium. We tested some culture conditions in order to preserve an acceptable morphology of cells inside the tubules. Seminiferous tubules were cultured during fifteen days in HAM F10 medium supplemented with fetal calf serum (FCS) and/or follicle-stimulating hormone (FSH). The cellular morphology was analyzed using scanning and transmission electron microscopy. During the culture period cellular degeneration occurred progressively. Morphological modifications of the Sertoli cells and germ cells such as accumulation of lipid droplets, nuclear and cytoplasmatic vacuolization and the presence of cell debris were observed. The addition of FCS activated the myoid cells causing nuclear rounding and thickening of the tubular wall. The best results were obtained with a serum-free culture medium supplemented with FSH.     

Distinct changes in the laminin composition of basement membranes in human seminiferous tubules during development and degeneration.

We studied the distribution of laminin (Ln) chains and their integrin (Int) receptors in normal developing and adult and in atrophied human testes by using immunohistochemistry. Immunostaining for EHS Ln and type IV collagen was used to identify basement membranes (BMs). In the BM of seminiferous epithelium of fetal testis, a panel of monoclonal antibodies showed immunoreactivity for Ln alpha 1-, alpha 2-, beta 1-, beta 2- and gamma 1-chains, suggestive of the presence of Lns 1 to 3. In BM of adult seminiferous epithelium with active spermatogenesis, immunoreactivity for Ln beta 2- and gamma 1-chains was found but not for Ln alpha-chains, suggesting a complex of Ln chains not compatible with any known trimers. Instead, with polyclonal Ln antiserum and monoclonal antibody to type IV collagen, a distinct BM-like reactivity was seen. In atrophied testes, prominent immunoreactivities for Ln chains, compatible with Lns 1 to 3, were seen in the thickened BM of seminiferous tubules, hence suggestive of reappearance of fetal Lns. Among the subunits of Ln-binding Int receptors in fetal seminiferous tubules, a strong immunoreactivity for Int beta 1- and Int alpha 6-subunits was seen throughout the seminiferous epithelium, other Int subunits being found in interstitial cells. In the adult and atrophied testes, immunoreactivities for Int beta 1- and Int alpha 6-subunits were seen to be confined to the basal aspect of the seminiferous epithelium whereas immunoreactivities for Int alpha 1-, alpha 2-, alpha 3- and beta 4-subunits were seen in the myoid cells. The results show that both maturation and degenerative changes of human testes are accompanied by distinct changes in the Ln expression of BM of seminiferous epithelium, which appears to accompany epithelial differentiation of the Sertoli cells. Furthermore, they suggest the presence of a novel Ln trimer in BM of adult human seminiferous tubules.     

Morphometric study of the prepubertal rabbit testis: Germ cell numbers and seminiferous tubule dimensions

Testes from rabbits aged 1–9 weeks were examined by light microscopy. Changes in seminiferous tubule dimensions, testicular volume, and volume fraction of tubules were assessed. Germ cells and Sertoli cells were counted in round tubular cross sections and total germ cell number in each testis was estimated. Mitotic, meiotic, and degenerative activities of germ cells as well as their basal or central positions within tubules were quantified. A marked, steady increase in testis volume and in tubular length and volume occurred over the prepubertal period; but diameter underwent no significant increase and in fact decreased until week 4. Overall, tubules lengthened 40-fold and testis volume increased 25-fold; the percentage volume of the testis occupied by tubules rose from one-third neonatally to three-fifths at the onset of spermatogenesis. The ratio of germ cells to total tubular (germ and Sertoli) cells was lowest at 3 weeks. However, the total number of germ cells increased little until 3 weeks, after which it rose at a sharp rate commensurate with testis volume. Percentage of germ cells in mitosis peaked sharply at 3 weeks, dropped in subsequent weeks, and then rose at 7 weeks at the initiation of spermatogenesis. Importantly, the surge in mitosis at 3 weeks was followed by a redistribution of germ cells to a predominantly basal location from 3 to 7 weeks. Meiotic activity was sparse at 7 weeks and became abundant by 9 weeks. Germ cell degeneration remained relatively constant during weeks 1 through 6, with an increase at 7 weeks.     

Histological alterations in the testicular tissue induced by sildenafil overdoses

Twenty adult male rabbits (Oryctolagus cuniculus) received sildenafil (0, 1, 3, 6, 9 mg/kg/day) for 4 weeks to investigate the testicular histological alterations induced by overdoses of this drug. Exposure to overdoses of sildenafil had provoked tubular and interstitial histological alterations. Abnormality in the germinal epithelium of the seminiferous tubules included spermatocytes karyopyknosis, spermatocytes degeneration, desquamation, spermatid giant cells and arrest of spermatogenesis. Additionally, increased Leydig cells cellularity, tubular degeneration, thickening of the interstitium were also observed. The encountered histological findings indicate that chronic exposure to sildenafil overdoses produces significant morphological and histological alterations in the testes which finally might lead to complete arrest of spermatogenesis.     

人与几种常用啮齿动物曲细精管周组织超微结构及碱性磷酸酶电镜细胞化学的定位

本文对人、兔、豚鼠、大鼠及小鼠的曲细精管周组织的超微结构和碱性磷酸酶(AIP)定位进行了观察。人的曲细精管周组织内一般有3层细胞,有细长分支突起,最内层呈肌样细胞特征,向外层的细胞则与成纤维细胞相似。相邻肌样细胞之间多见较宽的细胞间隙。AIP 位于基板、最内侧胶原原纤维区、肌样细胞胞质和向内侧质膜。4种啮齿动物曲细精管周组织微细结构基本相似,但也有某些区别。兔与豚鼠的单层肌样细胞的相邻末端可重叠排列呈2层,而大鼠和小鼠的肌样细胞则呈单层包绕。兔的基板为1～2层,其它3种动物只有1层。4种动物的相邻肌样细胞之间皆有紧密连接与宽度为100～200(?) 的开放间隙,以及更宽的细胞间隙。这4种动物的基板、内非细胞层、肌样细胞胞质及其向内侧质膜和淋巴窦内皮细胞皆有 AIP 分布,除兔以外,豚鼠、大鼠和小鼠的肌样细胞外侧质膜和外非细胞层也有 AIP 分布。本文讨论了曲细精管周组织及 AIP 酶鞘的生理意义。     

Morphogenesis of the bovine rete testis: the intratesticular rete and its connection to the seminiferous tubules

The development of the intragonadal rete testis and the establishment of the connection between seminiferous and straight testicular tubules was studied using ultrastructural and histochemical methods in 60 bovine embryos and fetuses ranging from day 39 through day 225 post conceptionem. The methodology included a modified acetylcholinesterase (AChE) reaction as a selective marker for pre-Sertoli cells and a modified microsomal aminopeptidase (MAP) reaction as a selective marker for the epithelia of rete testis and straight testicular tubules. Between 40 and 45 days, the rete testis is predominantly an extratesticular rete situated in the cranial peduncle of the gonadal fold and in broad contact with the pro/mesonephric giant corpuscle. During this period, the intragonadal rete enters the gonad proper from its craniodorsal pole and extends into the cranial fourth of the testis. Between 60 and 110 days the rete testis attains its definitive position, extending into the central longitudinal axis as far as to the caudal fourth of the testis. For the caudal expansion of the rete testis the preceding proliferation of the mediastinal stroma is an important prerequisite. In the 40 to 45-day-old embryo the area of the testicular cords may be divided into two zones. A narrow outer zone contains plate-like cords with a thick diameter, and a larger central zone is filled with a network of thinner cords. Only the thick outer cords transform into the permanent seminiferous tubules, whereas the thinner cords in the central zone are transitory structures that disappear between 45 and 110 days. One important function of these transitory cords is to establish a continuous system of basal laminae that allows a direct connection between the central ends of the growing seminiferous tubules and the peripheral extensions of the rete testis (future straight testicular tubules). The first true straight testicular tubules become visible between 85 and 110 days. Due to a strong proliferation of the tubulus rectus-cells the straight testicular tubules elongate continuously, and the border between the rete system and the seminiferous tubules is slowly shifted towards the testicular periphery. This shift is not restricted to the prenatal period, but proceeds until after birth. At the cytological level, the formation and elongation of the straight testicular tubules is effected by proliferating cells that advance along the continuous basal lamina into the area of the seminiferous tubules. The pre-Sertoli and germ cells in this zone of invasion are separated from each other and overgrown by the tubulus rectus-cells. Exposed to the special milieu of the straight testicular tubules, pre-Sertoli and germ cells apparently cannot survive and finally disappear. Accepted: 31 July 2000     

The influence of vasovasostomy on testicular alterations after vasectomy in Lewis rats

The occurrence of alterations in testicular weight and morphology after vasectomy and vasectomy reversal by vasovasostomy was studied in Lewis rats. Animals were studied 3, 4, and 7 months after bilateral vasectomy or a vasectomy followed 3 months later by vasovasostomy. Other rats served as sham-operated controls. The weights of the testes in vasectomy and vasovasostomy animals fell into two groups-small testes weighing less than 0.88 g and normal-sized testes of 1.2 g or more. When the extent of testicular alterations was estimated in sections for light microscopy by use of a semiquantitative testicular biopsy score count (TBSC), the morphology of the testes corresponded closely to the testis weight (r = .94), small testes having correspondingly low TBSC scores. In severely altered small testes, the seminiferous tubules were narrower than in sham-operated rats, and numbers of germ cells were greatly depleted. Many tubules contained only Sertoli cells and spermatogonia, although spermatocytes were present in a minority of tubules. A few seminiferous tubules contained multinucleate spermatids. Electron microscopy of severely altered tubules revealed closely apposed processes of Sertoli cells, which contained filaments, microtubules, and endoplasmic reticulum. In contrast, testes with normal weight in vasectomy and vasovasostomy groups resembled those of the sham-operated animals. Comparison of distributions of testicular biopsy score counts demonstrated differences between vasectomy and vasovasostomy groups as time after operation increased. At the 3-4-month intervals, approximately one-third of the testes were severely altered in both vasectomy and vasovasostomy groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Postnatal development of the sertoli cell barrier,tubular lumen,and cytoskeleton of sertoli and myoid cells in the rat,and their relationship to tubular fluid secretion and flow

The postnatal development of the Sertoli cell barrier, tubular lumen, fluid flow, and cytoskeletal elements in Sertoli and myoid cells was investigated in the Sprague-Dawley rat. With the aid of hypertonic fixatives, a barrier to the rapid entry of fluid was noted in the majority of tubules on the 15th and 16th postnatal (p.n.) days and was completely formed in all tubules prior to p.n. day 18. The actin forming the ecto-plasmic specialization (ES), a cytoskeletal complex related to the occluding junctions composing the barrier, began its development during the period of initial barrier formation (16 p.n. day) and progressively attained its adult prominence. The ES developed its characteristic adult pattern and adult fluorescent intensity at about p.n. day 22. Some seminiferous tubules showed very small lu-mina as early as p.n. day 10. All tubules were not open until p.n. day 30. The size (diameter) of the lumen increased slowly from p.n. day 10 until p.n. day 30 when it started to increase rapidly until about p.n. day 50. Fluid flow in seminiferous tubules was detected as early as p.n. day 20 and increased in amount thereafter. Myoid cell actin filament bundles, running in parallel, were present at p.n. day 10. Actin formed a meshwork pattern characteristic of the adult on, or slightly prior to, p.n. day 22. These data indicate that there is a temporal relationship between the development of the actin cytoskeleton within the Sertoli cell and initial formation of the Sertoli cell barrier. Similarly, there is a temporal relationship between the development of the actin cytoskeleton of myoid cells and tubular fluid flow. The rapid increase in tubular lumen diameter, however, does not correlate with the initial development of Sertoli and myoid cytoskeletal elements.