The blood - testis barrier and steroids.
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Androstane-3,17-diol↗
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[Cystic testis dysplasia with ipsilateral kidney agenesis].
A 6-year-old boy was seen for a left side scrotal mass which developed within a few months. Orchidectomy revealed an enlarged testis with multiple cysts in the head of epididymis and cystic transformation of the rete. At the same time, ipsilateral renal agenesis was found. This is a very rare combined malformation of the urogenital system which is of unknown etiology. Its pathogenesis may be related to developmental defects at the proximal and distal portion of the wolffian duct.
Child↗
Non germinal tumors of the testis.
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Adenoma↗
Concentrations of seven elements in the intraluminal fluids of the rat seminiferous tubules, rate testis, and epididymis.
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Animals↗
Pharmacokinetic and adaptation factors involved in testicular toxicity.
In the male gonads, factors that modify toxicity include the pharmacokinetic parameters governing the absorption, distribution, activation, and detoxication of toxicants; covalent binding to macromolecules; and DNA damage as well as DNA repair of damaged germ cells. All of these factors are being studied in our laboratory at the present time. The male germ cells are protected by a biological barrier comparable to that which retards the penetration of chemicals to the brain; permeability constants for the two are nearly identical. Toxication and detoxication processes are present in both the seminferous tubule and interstitial cellular compartments. The balance of toxication-detoxication processes apparently favors the germ cells; detoxication reactions are relatively more abundant in the seminiferous tubules. Unscheduled DNA repair has been shown in spermatogonia and spermatocytes; spermatids and sperm lack DNA repair capability. The DNA repair capacity associated with spermatogenic cells appears to be dose-dependent and saturable. Understanding the pharmacokinetic characteristics of the blood-testis barrier, toxication and detoxication mechanisms as well as DNA repair systems in male gonads will allow a better understanding of species comparison and reproductive and genetic toxicity. This understanding will also increase the reliability of extrapolating laboratory animal data to man and estimating human risk.
Animals↗
The difficult MESA: findings from tubuli recti sperm aspiration.
PURPOSE: To investigate sperm quality aspirated from the tubuli recti compared to that obtained from microsurgical epididymal sperm aspiration (MESA). METHODS: Sixteen patients with congenital bilateral absence of the vas deferens (CBAVD) underwent MESA. Six MESA procedures were difficult, and therefore sperm were retrieved from the tubuli recti ductules. Intraoperative sperm parameters, recovery after freeze-thaw, and ICSI outcomes were analyzed and compared between tubuli recti and MESA sperm. RESULTS: Mean initial sperm concentration was similar in both groups (18 vs. 16 million sperm/mL). Initial sperm motility was significantly higher in the tubuli recti group (35%) than the MESA group (25%). However, post thaw motility was higher with MESA compared to tubuli recti sperm (8.7 vs. 1.5%). ICSI fertilization rates after sperm freeze-thaw were 66% for tubuli recti sperm and 71% for MESA sperm. CONCLUSIONS: Tubuli recti sperm may provide an attractive alternative to testis sperm extraction. Poor sperm recovery after freeze-thaw should be expected.
Epididymis↗
Physiological significance of fluid secretion in the testis and blood-testis barrier.
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Amino Acids↗
Histology of the normal testis.
The gross and microscopic features of the normal adult, prepubertal, and aging testis are described. Qualitative and quantitative parameters of spermatogenic activity are presented in practical terms. Emphasis is placed on these findings, which are important to the pathologist in interpretation of diagnostic biopsy specimens other than neoplasms.
Adolescent↗
Sequential expression of type IV collagen networks: testis as a model and relevance to spermatogenesis.
The six alpha chains of type IV collagen are organized into three networks: alpha1/alpha2, alpha3/alpha4/alpha5, and alpha1/alpha2/alpha5/alpha6. A shift from the alpha1/alpha2 to the alpha3/alpha4/alpha5 network occurs in the developing glomerular basement membrane, but how the alpha1/alpha2/alpha5/alpha6 network fits into this sequence is less clear, because the three networks do not colocalize. Here, we studied the seminiferous tubule basement membrane of normal canine testis where all three networks do colocalize: the alpha1/alpha2 network is expressed from birth, the alpha1/alpha2/alpha5/alpha6 network by 5-6 weeks of age, and the alpha3/alpha4/alpha5 network by 2 months of age. A canine model of Alport syndrome allowed study of the absence of alpha3/alpha4/alpha5 and alpha1/alpha2/alpha5/alpha6 networks in testis. In Alport dogs, the seminiferous tubule basement membrane was thinner than in controls. Spermatogenesis began at the same time as with normal dogs; however, the number of mature sperm was significantly reduced in Alport dogs. Thus, it would appear that alpha3/alpha4/alpha5 and alpha1/alpha2/alpha5/alpha6 networks are not essential for onset of spermatogenesis, but long-term function may be compromised by the loss of one or both networks. This situation is analogous to the glomerular basement membrane in Alport syndrome. In conclusion, testis can serve as a model system to study the sequence of type IV collagen network expression.
Animals↗
Tubular ectasia within the mediastinum testis.
Eleven scrotal sonographic examinations showing a spectrum of findings within the mediastinum testis were collected over a 2 year period. Each case showed numerous small tubular or rounded anechoic structures within the mediastinum testis; often, the findings mimicked a hypoechoic mass. Findings were bilateral in eight of ten patients; one additional patient had only one testis because of orchiectomy. All patients had an associated extratesticular finding, in most cases a spermatocele. Tubular ectasia shares several features with testicular cysts and mechanisms of formation are postulated to be similar to those previously proposed for testicular cysts. Recognizing tubular ectasia is important to avoid unnecessary concern and potential surgery.
Aged↗
Intraepithelial lymphocytes in the excurrent ducts of the testis of the domestic fowl (Gallus domesticus).
Cells considered to be lymphocytes are reported in the epithelial lining of the excurrent ducts of the testis of normal and vasoligated domestic fowl. They resemble those already reported in the rat and monkey epididymal epithelium, the human intestinal mucosa, and in the bursa of Fabricius. The cytoplasm is usually less dense than that of adjacent epithelial cells, and contains only a few organelles. The nucleus is highly heterochromatic and with no definite nucleolus. Cytoplasmic processes are found to extend from the cell in between epithelial cells. The possible role of these cells in the reproductive tract of the cockerel is discussed.
Animals↗
Intra-epithelial lymphocytes in the normal epididymis. A mechanism for tolerance to sperm auto-antigens?
Using a monoclonal immunoperoxidase technique on frozen tissue sections of normal testis and epididymis, a distinctive distribution of lymphocytes has been identified. Almost all of the intra-epithelial lymphocytes were T cells and the majority of these belonged to the T8+ ("suppressor/cytotoxic") subset. The distribution contrasted with the predominance of the T4+ ("helper/inducer") subset in the interstitial tissues and in normal peripheral blood. The predominance of the "suppressor/cytotoxic" subset within the epithelium of the epididymis may exist in order to prevent the development of the immune response to auto-antigens on spermatozoa.
Adult↗
The concentration of carnitine in the luminal fluid of the testis and epididymis of the rat and some other mammals.
Luminal fluid was collected by micropuncture techniques from the testis and epididymis of the rat, hamster, rabbit, boar and ram and the concentration of free L-carnitine in the fluid was estimated using enzymic methods. Carnitine was present in the testicular fluid of the rat in concentrations less than 1 mM but increased down the epididymis to reach 53 mM in luminal fluid from the cauda epididymidis, approximately 2000 times higher than in blood plasma. A high concentration was first found in the luminal fluid from the distal caput epididymidis, at about the point where the spermatozoa become motile. Carnitine was also present in the epididymal luminal fluid of the other species studied; the amounts were not as high as those in the rat but were still higher than those in blood plasma.
Animals↗
Characterization of a cytoplasmic androgen receptor in the ram testis.
An androgen receptor has been characterized in the cytosol fraction of testes from hypophysectomized adult rams after in vitro labelling with [3H]testosterone. It can be distinguished from the testicular androgen-binding protein (ABP) and from the plasma 5 alpha-dihydrotestosterone-binding protein by electrophoresis on 3.25% acrylamide gels (Rx = 0.5) and on agar gels (anodic migration). It sediments in the 4S region in sucrose gradient containing 0.4 M KCl. Its complex with testosterone dissociates very slowly (t 1/2 = 29 h at 0 degrees C), and is destroyed by heating at 50 degrees C for 30 min and by pronase. Its relative affinities for steroids are 5 alpha-DHT greater than T greater than 5 alpha-androstanediols greater than cyproterone acetate greater than estradiol greater than progesterone. The number of binding sites is limited (about 20 fmoles/mg protein) and the apparent equilibrium dissociation constant (KD) is 5 x 10(-9) M.
Adsorption↗
[Effects on the mouse epididymis of juvenile ligation of the ductuli efferentes or proximal epididymal duct: qualitative and quantitative histological studies (author's transl)].
The ductuli efferentes or the epididymal duct between the head and body were ligated in young mice aged 20-30 days, and effects of the ligation on the epididymis were histologically examined by means of qualitative and quantitative procedures at the age of 50-60 days. As reported previously (Takano, 1980), the epididymal duct of the mouse can be divided into five regions (regions I-V). On the morphometric basis, the five regions can be divided into two major portions, proximal and distal. The proximal portion consists of regions I, II and III which form the head of the epididymis. The distal portion is composed of regions IV and V which form the body and tail of the organ. The results of the qualitative and quantitative analysis in the previous study suggested that the proximal portion is functionally related with maturation of sperms and the distal portion is concerned with storage of sperms. Juvenile ligation of the ductuli efferentes or the epididymal duct between the proximal and distal portions caused the following changes in the epididymal duct. 1. Region I, "initial segment", was normally characterized by the lining of high columnar epithelial cells. Juvenile ligation of the ductuli efferentes impaired differentiation of region I, but not that of the remaining regions. Epididymal duct ligation between regions III and IV, on the other hand, exerted no influence on differentiation of the entire duct. Thus differentiation of region I is dependent upon the luminal contents transferred from the testis. 2. The luminal contents were stored in abundance in the distal portion after ligation of the ductuli efferentes, as were in the case of the normal control. On the other hand, the luminal contents were abundant in th proximal portion and scanty in the distal portion after epididymal duct ligation between the proximal and distal portions. These results suggest that the luminal contents may be produced in the proximal portion even after ligation of the ductuli efferentes, transported into the distal portion and stored there. 3. In region IV, the epithelium showed marked histological changes after ligation of the ductuli efferentes or the epididymal duct between regions III and IV. After ligation of the ductuli efferentes, PAS-positive granules and masses frequently appeared in the epithelial cells. After epididymal duct ligation between regions III and IV, clear vacuolated cells and large vacuole-like spaces frequently appeared within the epithelium. Thus it is likely that the epithelial cells of region IV are functionally related to the luminal contents stored.
Alkaline Phosphatase↗
Postnatal differentiation of efferent ductule epithelium in goats: a light microscopic and ultrastructural study.
Caprine efferent ductule epithelium contains ciliated and nonciliated cells. The latter cells are divided into three types: type II cells contain PAS-positive granules, type III cells contain PAS-negative vacuoles, and type I cells lack both granules and vacuoles (Goyal and Williams, Anat. Rec. 220:58-67). The objectives of this study are i) to determine when the epithelium differentiates into ciliated and nonciliated cells, ii) to determine when nonciliated cells acquire characteristics typical for type II and type III cells, and iii) to relate developmental changes in the epithelium with those in the testis. Testes and efferent ductules were examined at the light and electron microscopic levels in goats from 1-25 weeks of age. Efferent ductule epithelium contained ciliated and nonciliated cells as early as week 1. While ciliated cells were differentiated at week 1, differentiation of nonciliated cells did not occur until week > or =15. Differential features in ciliated cells included the presence of cilia at the apical border and an aggregation of mitochondria in the apical cytoplasm. Those in nonciliated cells included the presence of i) an endocytotic apparatus at week > or =15, ii) PAS-positive granules at week > or =15, and iii) PAS-negative vacuoles at week > or =25. The seminiferous tubules developed lumens at 12-15 weeks. Hence, while differentiation of ciliated cells occurred much before lumen formation in the seminiferous tubules, that of nonciliated cells coincided with, or occurred soon after, lumen formation, suggesting a role for testicular fluid contents in their differentiation. The goat efferent ductules can be characterized morphologically mature by 25 weeks.
Age Factors↗
The ductuli efferentes testis of the greater cane rat ( Thryonomys swinderianus).
The structure of the efferent ducts of animals is known to vary from one species to another, it even varies between segments of the ducts in the same species. In the grasscutter or greater cane rat ( Thryonomys swinderianus), there are three segments of the efferent duct, based on their content of non-ciliated or principal cell types. Type I non-ciliated cell is present exclusively in the long proximal part of the duct, and exhibits a well-developed subapical endocytic apparatus as well as numerous oval or pleomorphic dense bodies. The type II non-ciliated cell predominates in the middle part of the duct, displays a poorly developed subapical endocytic apparatus but contains large, numerous vacuoles and dense bodies, all of which fill about two-thirds of the cell height. The type III non-ciliated cell, found in the epithelium of the terminal part of the duct, is poorly endowed with a subapical endocytic apparatus and contains no conspicuous endocytic vesicles or vacuoles. Only a few, small, dense bodies are present, if at all. The efferent duct of the cane rat is thus similar to that of man, the bull, goat and dog, in containing three varieties or types of non-ciliated cells. This report is the first to describe multiple non-ciliated cells in the epithelium of the efferent ducts of a rodent and, indeed, of a mammal smaller than the dog.
Animals↗
Extratesticular extension of germ cell tumors preferentially occurs at the hilum.
Germ cell tumors that extend beyond the testis are associated with a higher risk of metastasis. However, it is not known whether extratesticular invasion occurs at a preferential site. We reviewed all primary testicular germ cell tumors resected at the Brigham and Women's Hospital, Boston, MA, between July 1, 1987, and July 31, 1997. Of 142 total cases, 23 (16.2%) cases showed extratesticular extension. Thirty additional cases (21.1%), which had lymphatic or vascular invasion only, without interstitial involvement of extratesticular structures, were excluded. Extratesticular extension most likely occurred only at the hilum in 21 (91%) cases; 2 additional cases (9.5%) with tumor in the epididymis did not contain sections of hilum; however, the tunica albuginea was well sampled in these cases, and no separate site of tunica invasion was found. Multiple sections of the tunica albuginea were present in all cases, and penetration of the tunica albuginea was not identified in any case. Extratesticular extension was identified on gross examination of the orchiectomy specimen in only 8 of 18 (44%) cases. Extratesticular extension of germ cell tumors preferentially occurs at the hilum, and frequently the extension at this site is grossly inapparent. Histologic examination of the hilum should be performed in all cases of testicular germ cell tumors.
Germinoma↗