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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glucocorticoids administration presumably affects the vascular system and causes avascular necrosis of the femoral head. However, the mechanism by which this occurs is still unknown. In order to clarify the action of glucocorticoids on the vascular system, we investigated the effects of dexamethasone on an angiogenesis model in vitro. The angiogenesis model was obtained by co-culturing vessel fragments and myofibroblastic cells from rat epididymal fat pads. In this model, myofibroblastic cells induce capillary formation by producing an endothelial cell growth factor and collagen. Dexamethasone at physiological doses inhibited significantly capillary growth by suppressing the collagen synthesis by myofibroblastic cells. However, dexamethasone had no effect on endothelial cells. These results indicate that glucocorticoids are related to the pathogenesis of avascular necrosis of the femoral head by inhibiting the repair of the vascular system in vivo.
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PMID:[The effects of glucocorticoids on angiogenesis in vitro]. 138 Sep 69

Transforming growth factor-beta 1 (TGF-beta 1) is angiogenic in vivo. In two-dimensional (2-D) culture systems microvascular endothelial cell proliferation is inhibited up to 80% by TGF-beta 1; however, in three-dimensional (3-D) collagen gels TGF-beta 1 is found to have no effect on proliferation while eliciting the formation of calcium and magnesium dependent tube-like structures mimicking angiogenesis. DNA analyses performed on 3-D cell cultures reveal no significant difference in the amount of DNA or cell number in control versus TGF-beta 1 treated cultures. In 2-D cultures TGF-beta 1 is known to increase cellular fibronectin accumulation; however, in 3-D cultures no difference is seen between control and TGF-beta 1 treated cells as established by ELISA testing for type IV collagen, fibronectin, and laminin. In 3-D cultures there is increased synthesis and secretion of type V collagen in both control and TGF-beta 1 treated cultures over 2-D cultures. Even though an equal amount of type V collagen is seen in both 3-D conditions, there is a reorganization of the protein with concentration along an organizing basal lamina in TGF-beta 1 treated cultures. EM morphological analyses on 3-D cultures illustrate quiescent, control cells lacking cell contacts. In contrast, TGF-beta 1 treated cells show increased pseudopod formation, cell-cell contact, and organized basal lamina-like material closely apposed to the "abluminal" plasma membranes. TGF-beta 1 treated cells also appear to form junctional complexes between adjoining cells. Immunofluorescence using specific antibodies to the tight junction protein ZO-1 results in staining at apparent cell-cell junctions in the 3-D cultures. Northern blots of freshly isolated microvascular endothelium, 2-D and 3-D cultures, using cDNA and cRNA probes specific for the ZO-1 tight junction protein, reveal the presence of the 7.8 kb mRNA. Western blots of rat epididymal fat pad endothelial cells (RFC) monolayer lysates probed with anti-ZO-1 label a 220 kd band which co-migrates with the bonafide ZO-1 protein. These data confirm and support the hypothesis that TGF-beta 1 is angiogenic in vitro, eliciting microvascular endothelial cells to form tube-like structures with apparent tight junctions and abluminal basal lamina deposition in three-dimensional cultures.
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PMID:Transforming growth factor beta 1 modulates extracellular matrix organization and cell-cell junctional complex formation during in vitro angiogenesis. 168 59

The ability of mouse epididymal and human ejaculated spermatozoa to bind to beads coated with various extracellular matrix components was examined. Mouse spermatozoa preferentially bound to beads coated with heparin (average values ranging between 6.2 and 8.8 sperm per bead were obtained in different experiments) and with chondroitinsulfate (6.2-7.0), and also, although with significant differences across replicate experiments, to beads coated with laminin (7.9-15.6 sperm per bead) and with collagen type I (6.1-18.5). Human spermatozoa bound to collagen-coated beads (15.4-22.6 sperm per bead) and, to a much lower extent, to chondroitin-sulfate-coated beads (3.2-4.7); they were also able to bind heparin-coated beads, although with ample differences between individual sperm donors (ranging between 0.8 and 18.7 sperm per bead). Very few human and mouse sperm bound fibronectin-coated beads; beads coated with albumin, hyaluronic acid, and chondronectin were always totally free of adhering sperm. The possible physiological role of the interactions between spermatozoa and extracellular matrix components are discussed.
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PMID:Selective binding of mouse and human spermatozoa to beads coated with extracellular matrix components. 212 12

Epididymal epithelial fragments, free of stromal elements were isolated from mature rats using two sequential collagenase digestions. Within 24 h these attached efficiently to a variety of substrates including glass, plastic, placental collagen, type IV collagen and epididymal extracellular matrix material. Cells spreading away from the fragments rapidly assumed a flattened, overlapping, monolayer appearance typical of epithelial cells in culture. Cells still associated with the fragments or adjacent to them remained more polarized and more closely resembled epididymal principal cells in vivo than did cells that had migrated to the periphery of the monolayer. Apical microvilli characteristic of these cells in vivo were common during the first 4 days in culture but diminished in number and size thereafter. Cultured cells maintained many of the structural features characteristic of principal cells in vivo, including a well developed Golgi apparatus, coated pits and vesicles, and many multivesicular bodies. An extensive filamentous network, shown immunocytochemically to consist of keratin, was present in the cytoplasm of all cells but was more obvious in flattened cells at the periphery of the monolayer. Rhodamine phalloidin labelling of filamentous actin showed that concentrations of actin occurred corresponding to microvilli on the apical surface, in a continuous ring just below the apical surface, and also in stress fibres at the base of the cells. Cells isolated and cultured from the distal caput epididymidis possessed lobulated nuclei, in contrast to the round or oval nuclei found in cells cultured from the proximal caput epididymidis. Cells from the distal caput epididymidis were also characterized by the presence of many lipid droplets in their cytoplasm. Autofluorescent granules were observed in epithelial cells from both regions but were larger and more numerous in cells isolated from the distal caput epididymidis. Tritiated thymidine incorporation by the cells after 4 days in culture showed that cells adjacent to the parent epithelial fragment were dividing at a greater rate than cells that had migrated to the periphery of the monolayer.
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PMID:Structural features of rat epididymal epithelial cells in vitro. 241 3

The effect of recombinant human tumor necrosis factor (TNF) on the capillary growth was evaluated using an in vitro angiogenesis model recently developed. Sprague-Dawley rat microvessel fragments, from epididymal fat pads, seeded onto the confluent culture of myofibroblastic cells from the same tissue origin, gave rise to microvascular networks on and in the multilayered myofibroblastic cells. In contrast, the capillary growth from the vessel fragments was markedly inhibited in the presence of 10-1,000 U TNF/ml. Monoclonal antibody against TNF completely neutralized the capillary growth inhibitory activity of TNF. The mode of angiogenesis inhibitory action of TNF was also examined by use of bovine capillary endothelial (BCE) cells and rat myofibroblastic cells. TNF exerted growth inhibitory and cytotoxic actions against BCE cells cultivated on the various basement membrane components, such as extracellular matrix secreted by BCE cells, fibronectin, laminin, and type IV collagen. An irreversible damage to most of the BCE cells was observed ultrastructurally after 60 hours' exposure to TNF. TNF, however, did not injure the myofibroblastic cells but rather stimulated their growth. These findings indicate that TNF inhibits in vitro capillary growth by its direct cytostatic and cytotoxic actions to microvascular endothelial cells.
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PMID:Tumor necrosis factor inhibiting angiogenesis in vitro. 244 19

Electrophysiological measurements were made on endothelial cells initially isolated as individual clones from bovine brain microvessels, and then grown as monolayers on a permeable support of glutaraldehyde-treated collagen gel. When transendothelial cell resistance (R) of the clones was measured, there was a range of values from a low of 157.4 +/- 4.5 omega.cm2 (n = 6) to a high of 783.2 +/- 7.0 omega.cm2 (n = 34). With the high-resistance cells, there was also a small potential difference of -0.46 +/- 0.03 mV luminal-side negative (n = 34). In comparison, endothelial cells from bovine aortas and rat epididymal fat pads cultured on the collagen gels had transendothelial R values of 13.5 +/- 0.2 (n = 62) and 0.45 +/- 0.03 (n = 10) omega.cm2, respectively. Exposure of the high-resistance brain endothelial cell monolayers to a Ca2+-free medium for 10 min decreased the R to 75% of the control values. Addition of Ca2+ back to the medium caused a return of the transendothelial R to control values within 1 h. Endothelial cells were also grown to confluency on microcarrier beads for permeability measurements to Evans blue dye-bovine serum albumin. Microcarriers with no cells (control) and microcarriers with bovine and epididymal endothelial cell monolayers showed no difference in the amount of adsorbed dye. Microcarriers with brain endothelial monolayers excluded up to 80% of the dye. This mammalian brain endothelial culture system will be a useful model for studies of the electrophysiological and permeability properties of the blood-brain barrier.
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PMID:Electrical resistance and macromolecular permeability of brain endothelial monolayer cultures. 342 32

The ductuli efferentes of the pig have 2 distinct and continuous segments: the proximal or intratesticular segment that is formed in sequence to the labyrinthic portion of the rete testis, on the cranial extremity of the testis, and the distal or epididymal segment that forms the Cani vasculosi or Lobuli epididymidis. The testicular ductuli are more thicker and the epididymal ductuli are more thin, long and flexuous. The last segment is very coiled and forms a bulboid structure that is placed in the head of the epididymis, in which the ductuli jumped into the initial segment of the epididymis. Each efferent duct is formed by a single and cuboidal/columnar epithelium in which are identified three cellular types: ciliated cells, non ciliated cells and intra-epithelial lymphocytes. The epithelial lining rests on a conspicuous basement membrane that is surrounded by collagen fibrils. Among the ductuli is identified a loose connective tissue.
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PMID:[Structure of the efferent ductules of the domestic pig (Sus scrofa domestica)]. 360 39

To determine if ram principal cells can synthesize or metabolize testosterone, or metabolize other steroids present in rete testis fluid, principal cells from the initial segment, central caput, and proximal corpus epididymidis were isolated and cultured in a floating collagen matrix with medium containing 20% dialyzed rete testis fluid. In the first experiment, each matrix was washed twice in testosterone-free medium on day 2.8, transferred into culture medium containing 100 nM of a tritiated steroid and incubated for 4 hours at 34 C. The tritiated steroids were pregnenolone, 5-androstene-3 beta,17 beta-diol, progesterone, 4-androstene-3,17-dione, testosterone, and dihydrotestosterone. Since testosterone was not formed from 5-androstene-3 beta,17 beta-diol or 4-androstene-3,17-dione, testosterone synthesis by ram principal cells is unlikely Pregnenolone and 5-androstene-3 beta,17 beta-diol were not metabolized and only slight metabolism of dihydrotestosterone occurred. Progesterone, 4-androstene-3,17-dione, and testosterone were metabolized to 5 alpha-reduced products tentatively identified as 5 alpha-pregnane-3,20-dione and 5 alpha-pregnan-3 beta-ol-20-one and/or 5 alpha-pregnan-20 alpha-ol-3-one; 5 alpha-androstane-3,17-dione and 5 alpha-androstan-3 alpha-ol-17-one, and dihydrotestosterone, respectively. The second experiment evaluated testosterone metabolism by both cultured principal cells and minced epididymal tissue. On day 1 of culture, during 12 hours the accumulation of dihydrotestosterone in medium from cells of the central caput was 48 X and 1.1 X that in medium from cells of the initial segment and proximal corpus epididymidis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Steroidogenesis and testosterone metabolism in cultured principal cells from the ram epididymis. 362 61

The differentiation of male and female rat genital ducts and their basement membranes were studied by light- and electron-microscopic localization of type-IV and -V collagen, laminin, and heparan sulfate proteoglycan at the fetal ages of 15-21 days. At 15 days, the basement membrane of the mesonephric duct was continuous in both sexes, whereas on the medial side of the paramesonephric duct, it was incomplete. The male mesonephric duct remained enveloped by a continuous basement membrane. Increasing accumulation of basement-membrane material in the periductal mesenchyme was regarded as incipient epididymal differentiation. Local expansions and slow degradation of the basement membrane were noted in the regressing female mesonephric duct. The female paramesonephric duct had acquired a continuous basement membrane by the age of 16 days. At this age, the incomplete basement membrane in the medial side of the male paramesonephric duct disappeared, and breaks in the lateral portion appeared. The formation of epitheliomesenchymal contacts and basal cytoplasmic blebs in the epithelial cells of the regressing paramesonephric duct coincided with the disappearance of the basement-membrane material in the condensed periductal mesenchyme. The asymmetric regression of the male paramesonephric duct was initiated in the immature medial side. The changes in the periductal matrix are indications of basic differences in the regulation of the development and regression of the genital ducts in different sexes.
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PMID:Basement membrane in differentiating mesonephric and paramesonephric ducts of male and female rat fetuses. 401 59

Treatment of laboratory beagles with 400 micrograms of estradiol benzoate every fourth day from 5 to 20 wk of age severely alters the gross and microscopic morphology of the epididymis. Both stroma and epithelium are affected by estradiol treatment. The peritubular cells of treated animals appear to be fibroblasts separated by broad expanses of collagen, while the control peritubular cells resemble smooth muscle cells separated by small amounts of collagen. The single epithelial cell type present in the treated pup is low columnar and relatively undifferentiated in appearance. These cells appear to be synthetically active based on the accumulation of material within the lumen. The junctions of the epithelial cells of treated animals are occluding, but those of the control are not. The epithelium of control epididymides is composed of columnar principal cells in the caput epididymidis, and principal cells and basal cells in the pseudostratified epithelium of the corpus and cauda epididymidis. The epididymis of the intact, prepubertal dog is responsive to increased estrogen. The presence of estrogen and progesterone receptors (Jones and Connell, 1982) as well as androgen receptors (Younes et al., 1979) suggests that estrogens, progestins, and androgens all may play an essential role in the normal differentiation of the prepubertal epididymis. This is the first description of the ultrastructure of the epididymis of the 20-wk-old dog and the first description of the effect of chronic estrogen treatment on the ultrastructure of the epididymis of the intact prepubertal dog. We propose that the prepubertal dog epididymis is an excellent model system for the study of the hormonal control of epididymal differentiation and development.
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PMID:A morphological study of the epididymides of control and estradiol-treated prepubertal dogs. 408 38


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