Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The transport and storage of spermatozoa in the epididymis depend on the contractile activity of its tubular wall. It is not known what differences exist in the contractile wall of the human epididymis in cases of obstructive azoospermia. The contractile wall in the tubules of the caput epididymidis was analyzed by light microscopy and transmission electron microscopy in 10 azoospermic men, 5 with a bilateral congenital absence of vas deferens (CBAVD) and 5 with a bilateral postinflammatory congestive obstruction of the epididymis. Five specimens from the same region of the caput epididymidis, obtained from fertile men who had undergone an orchidectomy because of testicular cancer, served as controls. No differences were observed between congenital and congestive obstructions. The contractile wall in caput tubules proximal to the obstructed level was strongly thickened when compared with controls (62.98 +/- 5.84 micro; 80.82 +/- 7.72 micro vs 19.59 +/- 2.23 micro, respectively, for congestive and congenital obstructions vs controls; P <.0001 vs controls), and the spindle-shaped myoid cells, which formed the contractile wall in normal cases, were replaced by large smooth muscle cells (SMCs) that showed features of coexisting contractile and secretory functions. The former included crowded cytoplasmic bundles of thin myofilaments (5-6 nm in diameter) converging to a large number of dense bodies, numerous micropinocytotic vesicles of the plasma membrane, and a continuous cell basement membrane. The presence of a developed rough endoplasmic reticulum and a Golgi complex, associated with the accumulation of thick layers of pericellular basement membrane-like material and ground substance, was indicative of a secretory phenotype of SMCs. The increased mechanical forces on the epididymal wall upstream from the obstruction might eventually activate the differentiation of myoid cells into SMCs, leading to an altered physiology of the contractile wall that could have possible clinical relevance in the case of microsurgical epididymovasostomy.
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PMID:The contractile wall of the caput epididymidis in men affected by congenital or postinflammatory obstructive azoospermia. 1506 21

The benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya at a dose of 10 mg/rat/day for 150 days, which has shown a total inhibition of motility, reduced sperm count and infertility, was tested to de fi ne the mode of action at the subcellular level in the testis and epididymis. The ultrastructure of the testis of the treated animals revealed no appreciable changes in the subcellular characteristics. The mechanism of protein synthesis as well as steroidogenesis were evident in the Sertoli cells while the spermatogonia, spermatocytes and spermatids, both round and elongated, depicted a prominent nucleus, distinct nuclear membrane and cytoplasmic characteristics indicating normal germ cell differentiation. The principal cells of the cauda epididymis were characterized by the presence of well-de fi ned rough endoplasmic reticulum, mitochondria, Golgi bodies and secretary granules, suggesting active secretory functions. The absorptive function of the cauda epididymis was evidenced by the presence of numerous vesicles and multivesicular bodies adjacent to stereocilia. It is concluded that the inhibition of sperm motility by the drug could be due to other epididymal factors rather than the subcellular characteristics of testis and epididymis.
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PMID:Ultrastructural changes in the testis and epididymis of rats following treatment with the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya. 1516 62

In mouse, two different isoforms of ADAM1 (fertilin alpha), ADAM1a and ADAM1b, are produced in the testis. ADAM1a is localized within the endoplasmic reticulum of testicular germ cells, whereas epididymal sperm contain only ADAM1b on the plasma membrane. In this study, we show that the loss of ADAM1a results in the male infertility because of the severely impaired ability of sperm to migrate from the uterus into the oviduct through the uterotubal junction. However, epididymal sperm of ADAM1a-deficient mice were capable of fertilizing cumulus-intact, zona pellucida-intact eggs in vitro despite the delayed dispersal of cumulus cells and the reduced adhesion/binding to the zona pellucida. Among testis (sperm)-specific proteins examined, only the level of ADAM3 (cyritestin) was strongly reduced in ADAM1a-deficient mouse sperm. Moreover, the appearance of ADAM3 on the sperm surface was dependent on the formation of a fertilin protein complex between ADAM1a and ADAM2 (fertilin beta) in testicular germ cells, although no direct interaction between the fertilin complex and ADAM3 was found. These results suggest that ADAM1a/ADAM2 fertilin may be implicated in the selective transport of specific sperm proteins including ADAM3 from the endoplasmic reticulum of testicular germ cells onto the cell surface. These proteins then can participate in sperm migration into the oviduct, the dispersal of cumulus cells, and sperm binding to the zona pellucida.
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PMID:Possible function of the ADAM1a/ADAM2 Fertilin complex in the appearance of ADAM3 on the sperm surface. 1519 97

This work describes a protocol to culture epididymal epithelial cells from the caput, corpus, and cauda regions of Sus domesticus. Epididymal epithelial fragments were obtained by dissection and enzymatic digestion with collagenase. About 30 epididymal fragments from each epididymal region were cultured in 24-well culture plates with supplemented RPMI-1640 medium at 37 degrees C, 5% CO2 in air, and 100% humidity. A confluent monolayer of polygonal and tightly packed epithelioid cells from the three epididymal regions was obtained after 12-16 days in culture and maintained in vitro for more than 60 days. The proportion of epididymal epithelial cells in these cultures was assessed by immunofluorescent staining for cytokeratins. Throughout the 2 months of culture, about 80% of the cells were cytokeratin-positive. Electron microscopy observations indicated that cultured cells from caput, corpus, and cauda epididymal regions were tightly adhered to each other by junctional complexes and that stereocilia were present in their apical membranes. Moreover, the presence of an extensive rough endoplasmic reticulum, Golgi apparatus and numerous vesicles in the cytoplasm suggested that cultured cells maintained secretory and absorptive activities. These results show that the epididymal epithelial cells in culture from S. domesticus retain some fundamental features that characterize the epididymal epithelium in the intact organ. This system might be a valuable tool for studying the mechanism of sperm maturation in vitro, including epididymal cell secretions and the analysis of regional differences.
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PMID:In vitro culture of epithelial cells from the caput, corpus, and cauda epididymis of Sus domesticus. 1525 Dec 44

PHTF1 is an 84-86-kDa membrane protein found in the endoplasmic reticulum of male germ cells in rodents. There are no evident signs of PHTF1 in the spermatozoa released into the lumen of the seminiferous tubules but PHTF1 is present in the epididymal epithelium. Characterization of the epididymal Phtf1 messenger by Northern blot and reverse transcription-PCR identified a 3-kilobase transcript in the epididymis, similar to that previously reported in the testis. The transcript is present in the proximal part of the epididymis and it appears when the rats reach 4 wk of age. Through immunofluorescence analysis, PHTF1 was localized in the principal cells of the initial segment and the caput epididymis. Colocalization with different markers indicated PHTF1 is in the endoplasmic reticulum saccules applied to the trans face of the Golgi system. Western blot analyses revealed a shorter form of the protein--about 56-kDa versus the 84-kDa form found in the testis. Using the canine epididymal cell line CIM 20, transfected by N- and C-terminal myc-tagged PHTF1, we demonstrated that the 56-kDa epididymal form could result from proteolytical processing.
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PMID:Expression, regulation, and immunolocalization of putative homeodomain transcription factor 1 (PHTF1) in rodent epididymis: evidence for a novel form resulting from proteolytic cleavage. 1534 52

To assess if cauda epididymis is a target for the effect of A. indica leaves, Wistar strain male albino rats were administered (po) A. indica leaves (100 mg/rat/day for 24 days). Transmission electron microscopic analysis revealed that in the cauda epididymal epithelium the nuclei of principal cells were enlarged and the number of coated micropinocytotic vesicles of the apical cytoplasm decreased. Microvilli were missing and mitochondrial cristae and Golgi complex were highly disrupted. The cytoplasm was abounding with lysosomal bodies. The clear cells increased in perimeter and their nuclei increased in size and contained lesser chromatin. The nuclear membrane bulged out. The cytoplasm was vacuolized. Further, there was decrease in size of the lipid droplets, mitochondria, Golgi complex, endoplasmic reticulum and there was accumulation of lysosomal bodies. The changes in the principal and clear cells appear to be due to the effect of the hypoandrogen status caused by treatment with A. indica leaves and a direct action on the epididymal epithelium.
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PMID:Ultrastructural changes in cauda epididymidal epithelial cell types of Azadirachta indica leaf treated rats. 1558 15

Acyl-CoA:diacylglycerol acyltransferases (DGATs) catalyze the last step in triglyceride (TG) synthesis. The genes for two DGAT enzymes, DGAT1 and DGAT2, have been identified. To examine the roles of liver DGAT1 and DGAT2 in TG synthesis and very low density lipoprotein (VLDL) secretion, liver DGAT1- and DGAT2-overexpressing mice were created by adenovirus-mediated gene transfection. DGAT1-overexpressing mice had markedly increased DGAT activity in the presence of the permeabilizing agent alamethicin. This suggests that DGAT1 possesses latent DGAT activity on the lumen of the endoplasmic reticulum. DGAT1-overexpressing mice showed increased VLDL secretion, resulting in increased gonadal (epididymal or parametrial) fat mass but not subcutaneous fat mass. The VLDL-mediated increase in gonadal fat mass might be due to the 4-fold greater expression of the VLDL receptor protein in gonadal fat than in subcutaneous fat. DGAT2-overexpressing mice had increased liver TG content, but VLDL secretion was not affected. These results indicate that DGAT1 but not DGAT2 has a role in VLDL synthesis and that increased plasma VLDL concentrations may promote obesity, whereas increased DGAT2 activity has a role in steatosis.
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PMID:Increased very low density lipoprotein secretion and gonadal fat mass in mice overexpressing liver DGAT1. 1579 71

The epididymis is an androgen-dependent organ that allows spermatozoa to become fully functional as they pass through this tissue. The specialized functions of the epididymis are mediated by interactions between epididymal epithelial cells and between epididymal cells and spermatozoa. Although the critical role of the epididymis in sperm maturation is well established, the mechanisms regulating cell-cell interactions remain poorly understood because of the lack of appropriate cell line models. We now report the characterization of a novel rat caput epididymal cell line (RCE) that was immortalized by transfecting primary cultures of rat epididymal cells with the simian virus 40 large T antigen. At the electron microscope level, the cell line was composed of epithelial principal cells with characteristics of in vivo cells; principal cells had well-developed Golgi apparatus, abundant endoplasmic reticulum cisternae, and few endosomes. RCE cells expressed the mRNAs coding for the androgen receptor, estrogen receptor alpha, and 4-ene-steroid-5-alpha-reductase types 1 and 2 as well as epididymal-specific markers Crisp-1 and epididymal retinoic acid binding protein. Epididymal retinoic acid binding protein expression was significantly induced with dihydrotestosterone, although this effect was not blocked by flutamide, suggesting that RCE cells are not androgen responsive. Neighboring cells formed tight and gap junctions characteristic of epididymal cells in vivo and expressed tight (occludin and claudin-1, -3, and -4) and gap junctional proteins (connexin-26, -30.3, -32, and -43). The RCE cell line displays many characteristics of epithelial principal cells, thus providing a model for studying epididymal cell functions.
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PMID:Characterization of a novel rat epididymal cell line to study epididymal function. 1609 65

The leucine zipper motif has been identified as an important and specific interaction motif used by various sperm tail proteins that localize to the outer dense fibers. We had found that rat Odf1, a major integral ODF protein, utilizes its leucine zipper to associate with Odf2, another major ODF protein, Spag4 which localizes to the interface between ODF and axonemal microtubule doublets, and Spag5. The rat Spag5 sequence indicated a close relationship with human Astrin, a microtubule-binding spindle protein suggesting that Spag5, like Spag4, may associate with the sperm tail axoneme. RT PCR assays indicated expression of Spag5 in various tissues and in somatic cells Spag5 localizes to endoplasmic reticulum and microtubules, as expected for an Astrin orthologue. MT binding was confirmed both in vivo and in in vitro MT-binding assays: somatic cells contain a 58 kDa MT-associated Spag5 protein. Western blotting assays of rat somatic cells and male germ cells at different stages of development using anti-Spag5 antibodies demonstrated that the protein expression pattern changes during spermatogenesis and that sperm tails contain a 58 kDa Spag5 protein. Use of affinity-purified anti-Spag5 antibodies in immuno electron microscopy shows that in rat elongated spermatids and epididymal sperm the Spag5 protein associates with ODF, but not with the axonemal MTs. This observation is in contrast to that for the other Odf1-binding, MT-binding protein Spag4, which is present between ODF and axoneme. Our data demonstrate that Spag5 has different localization in somatic versus male germ cells suggesting the possibility of different function.
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PMID:Rat Spag5 associates in somatic cells with endoplasmic reticulum and microtubules but in spermatozoa with outer dense fibers. 1621 99

Passage of spermatozoa through the epididymis is obligatory for sperm maturation processes and is based on spontaneous phasic contractions (SC) of the epididymal duct. Here, the functional role of cyclic GMP (cGMP) signaling in modulating SC in the bovine epididymal caput and corpus region was examined by muscle tension recording and immunological and autoradiographic techniques. The cGMP-analog 8-bromo (Br)-cGMP, as well as the nitric oxide (NO) donor sodium nitroprusside and the natriuretic peptides (NPs) atrial NP and C-type NP, displayed distally increasing SC-relaxant effects. In agreement, a distally increasing epididymal expression of the cGMP-dependent protein kinase I (PKG I), endothelial NO synthase (eNOS), and the atrial NP receptor was found. Immunoreactivity for PKG, soluble guanylate cyclase, and eNOS could be localized to the epididymal muscle cells as well as to the epithelial basal cells only at the corpus level. The SC-relevant action of NO and the NPs was cGMP dependent, and the action of 8-Br-cGMP, in turn, was modified by epithelial and luminal factors. The NOS inhibitor L-NAME (N(omega)-nitro-L-arginine methyl ester) caused an increase in SC frequency, indicating basal activity of NO generating enzymes. The SC-inhibitory effect of 8-Br-cGMP was clearly reduced by the PKG inhibitor Rp-8-Br-cGMPS as well as by iberiotoxin, thapsigargin, and indomethacin, pointing to PKG as main SC-relevant target of cGMP, and to large-conductance calcium-activated K(+) channels, the sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase and cyclooxygenase-1 as possible targets of PKG. These data support an essential role of cGMP signaling in the control of epididymal peristalsis, thereby enabling fine tuning of sperm transport and maturation.
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PMID:Regulation of spontaneous contractile activity in the bovine epididymal duct by cyclic guanosine 5'-monophosphate-dependent pathways. 1643 52


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