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

Junctional complexes of the epithelia lining the rete testis, efferent ductules, connecting ductules and epididymal duct in the fowl were examined by transmission electron microscopy and by a tracer method using lanthanum nitrate. The junctional complexes were composed of tight junctions, adhering junctions and desmosomes. In the rete testis, one or two points of membrane fusion were observed at the tight junctions. In the efferent and connecting ductules and epididymal duct, the tight junctions consisted of a series of punctate membrane fusions. The adhering junctions and desmosomes showed no remarkable structural differences among these excurrent ducts. Vascularly infused lanthanum nitrate penetrated into the tight junctions of individual epithelia for variable distances, but was prevented from entering the lumen at the site of membrane fusion. These results suggest that the tight junctions can restrict the diffusion of materials via the paracellular route, and that they play an important role in maintaining a suitable fluid environment within the excurrent ducts.
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PMID:Ultrastructural study on junctional complexes of the excurrent duct epithelia in the epididymal region in the fowl. 183 9

Epididymal epithelial cells isolated from mature rats and Sertoli cells isolated from 10-day-old rats were cultured in serum-free defined media on extracellular matrix impregnated filters maintained in dual environment culture chambers. Epididymal epithelial cells had a polarized appearance only when plated at high density (greater than 1 X 10(6) cells/cm2). Confluent monolayers of these cells formed a permeability barrier to inulin. Sertoli cells were columnar and highly polarized when grown on extracellular matrix-impregnated filters, cuboidal when grown on filters alone, and squamous when grown on plastic. Confluent polarized monolayers of these cells excluded the electron-dense tracer lanthanum nitrate by way of basal-tight junctions. Therefore, polarized monolayers of epididymal epithelial cells and Sertoli cells can be obtained by growing the cells at high density on extracellular matrix-impregnated permeable supports. By maintaining the monolayers in specially constructed culture chambers, the cells can develop a permeability barrier, and are able to achieve the separation of apical from basal compartments so important for their function in vivo.
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PMID:Growth and characterization of polarized monolayers of epididymal epithelial cells and Sertoli cells in dual environment culture chambers. 394 21

Ultrastructural and micropuncture techniques were used to obtain morphological evidence for a blood-epididymis barrier ( BEB ) in the rat and to determine whether gossypol, an oral male contraceptive, alters the permeability of the BEB or blood-testis barrier ( BTB ) in rats made infertile with gossypol. Rats were treated by gavage with 20 mg/kg per day of gossypol for 6 weeks; control animals received the vehicle alone. For electron microscopy the components of the BEB were analyzed in each region of the epididymis with intravascularly perfused lanthanum nitrate. Throughout the epididymis in both control and gossypol-treated animals it was found that the zonula occludens at the apicolateral surface of the epididymal epithelial cells was the sole and ultimate structural component of the rat BEB ; the flow of intravascularly perfused lanthanum was not significantly impeded by the vascular endothelium, the peritubular myoid layer or other lateral cell surface specializations. For micropuncture, control and treated rats were administered 0.3 mCi [3H]inulin via the jugular vein. Radioactivity was determined in samples collected from the seminiferous tubules, caput and cauda epididymidis, and carotid artery. Results showed that [3H]inulin entry in seminiferous tubules, caput and caudal luminal fluid from blood was similar for control and treated groups. It was concluded that gossypol treatment does not alter the permeability properties of the BTB and BEB to macromolecules such as inulin or to small electron-dense tracers such as lanthanum.
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PMID:Morphological evidence for a blood-epididymis barrier and the effects of gossypol on its integrity. 673 4

The reproductive toxicology of aluminum was studied in mice. Adult male mice were treated intraperitoneally with aluminum nitrate at doses of 0, 50, 100, and 200 mg/kg/day for 4 weeks before mating with untreated females. Decreased body weight was seen in all aluminum-treated groups. Decreased pregnancy rate was observed in the females mated with males previously treated with 100 or 200 mg/kg/day of aluminum nitrate. High-dose male mice showed significantly decreased testicular and epididymal weights, as well as significant decreases in testicular and spermatid counts and epididymal sperm counts. Spermatid counts were also reduced at 100 mg/kg/day. However, the sperm motility was unaffected, and the percentages of morphological normal spermatozoa in all mice exposed to aluminum were comparable to the values in control mice. Histological changes, including necrosis of spermatocytes/spermatids, were observed in the testes of male mice treated with 100 and 200 mg/kg/day of aluminum nitrate, whereas the tubular diameters were unaffected by aluminum administration. The current study demonstrates adverse effects of parenteral aluminum exposure on the mouse male reproductive system. The "no observable adverse effect level" (NOAEL) was 50 mg/kg/day.
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PMID:Reproductive toxicology of aluminum in male mice. 760 26

Single rat epididymal cell studied under whole cell patch-clamp condition responded to 8-(4-chlorophenylthio)-adenosine 3',5'-cyclic monophosphate (CPT-cAMP) (500 microM) and to ionomycin (1 microM) by an increase in whole cell conductance. A major part of the stimulated current was carried by Cl-, although a small part was due to nonselective cation current. After elimination of the cation current component by using impermeant cation, the cells revealed different Cl- conductance properties in response to adenosine 3',5'-cyclic monophosphate (cAMP) and ionomycin. The cAMP-stimulated Cl- conductance was independent of time and voltage and showed a linear current-voltage relationship. The anion permselectivity was NO3- > Br- > Cl- approximately I- >> SO(4)2-. The ionomycin-stimulated Cl- conductance showed marked time and voltage dependency. In contrast to the cAMP-induced anion permselectivity, the ionomycin-induced anion permselectivity was I- > Br- approximately NO3- > Cl- >> SO(4)2-. These results indicate that the epididymal epithelial cells exhibit different Cl- conductances sensitive to cAMP and Ca2+. The cAMP-activated conductance has properties resembling the type associated with the cystic fibrosis transmembrane conductance regulator found in cystic fibrosis-affected epithelia. This finding supports the notion that the epididymis is a cystic fibrosis epithelium.
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PMID:Properties of cAMP-dependent and Ca(2+)-dependent whole cell Cl- conductances in rat epididymal cells. 768 72

Swelling-induced Cl- conductance in cultured rat epididymal cells was characterized using whole cell patch-clamp techniques. Activation of whole cell current with an outwardly rectifying current-potential relationship was observed in cells exposed to hyposmotic solutions. This current was determined, from the observed current-reversal potentials at different Cl- concentrations, to be Cl- selective. The anion selectivity sequence of the swelling-induced Cl- conductance was I- approximately NO3- approximately Br- > Cl- > 2-(N-morpholino)ethanesulfonic acid. The swelling-induced Cl- conductance was reversibly inhibited by different Cl- channel blockers. Unlike diphenylamine-2-carboxylate or 5-nitro-2-(3-phenylpropylamino)-benzoate, which showed voltage-independent blockade, 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid showed a marked voltage-dependent blockade of the volume-sensitive Cl- current, with a greater effect at depolarizing voltages. The swelling-induced Cl- conductance appeared to be different from the Ca(2+)- or adenosine 3',5'-cyclic monophosphate-activated Cl- conductances on the basis of the following observations: 1) swelling-induced current activation was seen even in the presence of kinase inhibitor (H-8) or absence of external free Ca2+, and 2) further increase in current activation could be produced by swelling after Ca(2+)- or adenosine 3',5'-cyclic monophosphate-induced current activation. The swelling-induced Cl- conductance may be involved in regulating epithelial cell volume as well as serving other important epididymal functions such as facilitating transepithelial secretion of organic compounds.
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PMID:Characterization of a swelling-induced chloride conductance in cultured rat epididymal cells. 769 76

The effects of ingestion of sodium fluoride (NaF), 10 mg/kg body weight for 50 days, on the structure and metabolism of sperm of albino rats (Rattus norvegicus), were investigated. In different groups of rats, the reversible effects upon withdrawal of NaF treatment and by administering some therapeutic agents, viz., ascorbic acid and calcium alone and in combination with NaF (50 and 70 days), on sperm structure and metabolism were also studied. The results revealed that the sperm acrosomal hyaluronidase and acrosin were reduced after 50 days of NaF treatment. Sperm stained with acidic alcoholic silver nitrate revealed acrosomal damage and deflagellation, which might be causative factors for the reduced activity of the enzymes. These alterations also resulted in a decline in sperm motility. The cauda epididymal sperm count was decreased, perhaps because of spermatogenic arrest. Thus, the low sperm motility and count ultimately contributed toward reduction in fertility by NaF treatment. However, withdrawal of NaF treatment for 70 days produced incomplete recovery, while administration of ascorbic acid and calcium, individually and in combination, brought about significant recovery of fluoride-induced effects. Thus, the effects of fluoride on sperm structure and metabolism of rats are transient and reversible.
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PMID:Reversible effects of sodium fluoride ingestion on spermatozoa of the rat. 788 87

1. Isolated cells from primary cultures of rat epididymal epithelial cells were employed for the study of adrenaline-stimulated Cl- transport using a Cl-(-)sensitive fluorophore 6-methoxy-N-(3-sulphopropyl) quinolinium (SPQ). SPQ was loaded into the cells by the hypotonic shock method. 2. The resting intracellular Cl- concentration, estimated in the presence of nigericin and tributyltin in high-K+ solution, was 62.3 +/- 0.2 mM. This value was not altered in the presence of 1 microM adrenaline. When extracellular Cl- was replaced by NO3-, an increase in fluorescence corresponding to a decrease in intracellular Cl- was observed. The initial outward Cl- movement was estimated to be 0.54 +/- 0.08 mM s-1. This value was increased by incubating the cells with adrenaline. The stimulatory effect of adrenaline was reduced by 1 mM DPC. 3. Addition of Cl- to cells previously depleted of Cl- caused an instantaneous decrease in fluorescence due to the entry of Cl-. The initial rate of Cl- entry was -0.62 +/- 0.13 mM s-1. Adrenaline increased the rate of entry to -2.13 +/- 0.08 mM s-1. The adrenaline-stimulated rate of entry was reduced by DPC or frusemide (0.5 mM) and was completely blocked in the presence of both agents. 4. In Na(+)-free solution, the adrenaline-stimulated rise of rate of Cl- entry was reduced in the presence of DPC. Frusemide had no effect on the entry rate. 5. The stimulatory effect of adrenaline were abolished by propranolol (5 microM) but not by phentolamine (5 microM). Conversely, isoprenaline (1 microM) and forskolin (1 microM) mimicked the effects of adrenaline.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Adrenaline-regulated Cl- transport in cultured single rat epididymal cells measured by an entrapped Cl-(-)sensitive fluorophore. 800 8

Pesticides and fertilizers, as used in modern agriculture, contribute to the overall low-level contamination of groundwater sources. In order to determine the potential of pesticide and fertilizer mixtures to produce reproductive or developmental toxicity at concentrations up to 100 x the median level found in groundwater, we prepared and studied two mixtures of pesticides and a fertilizer (ammonium nitrate). One mixture containing aldicarb, atrazine, dibromochloropropane, 1,2-dichloropropane, ethylene dibromide, and simazine plus ammonium nitrate was considered to be a representative of groundwater contamination in California (CAL). The other, containing alachlor, atrazine, cyanazine, metolachlor, metribuzin, and ammonium nitrate, simulated groundwater contamination in Iowa (IOWA). Each mixture was administered in the drinking water of either Swiss CD-1 mice during a Reproductive Assessment by Continuous Breeding study or pregnant Sprague-Dawley rats (gd 6-20) at three dose levels (1x, 10x, and 100x) where 1x was the median concentration of each pesticide component as determined in the groundwater surveys in California or Iowa. Unlike conventional toxicology studies, the purpose of this study was to evaluate the health effects of realistic human concentrations. Thus, the testing concentrations are probably well below the maximally tolerated dose. Propylene glycol was used as the solubilizer for the pesticides in drinking water formulations in both studies. In the reproductive study, neither mixture caused any clinical signs of toxicity, changes in food or water consumption, or body weight in either F0 or F1 mice at doses up to 100x the median groundwater concentrations. There were no treatment-related effects on fertility or any measures of reproductive performance of either the F0 or the F1 generation mice exposed to either CAL or IOWA at up to 100x. Similarly, measures of spermatogenesis, epididymal sperm concentration, percentage motile sperm, percentage abnormal sperm, and testicular and epididymal histology were normal. In the developmental study, CAL- or IOWA-exposed females did not exhibit any significant treatment-related clinical signs of toxicity. No adverse effects of CAL or IOWA were observed for measures of embryo/fetal toxicity, including resorptions per litter, live litter size, or fetal body weight. CAL or IOWA did not cause an increased incidence of fetal malformations or variations. In summary, administration of these pesticide/fertilizer mixtures at levels up to 100-fold greater than the median concentrations in groundwater supplies in California or Iowa did not cause any detectable reproductive (mice), general, or developmental toxicity (rats).
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PMID:Assessment of the reproductive and developmental toxicity of pesticide/fertilizer mixtures based on confirmed pesticide contamination in California and Iowa groundwater. 805 7

A study was conducted with nitrate to assess the testicular and spermatotoxic effects in mice at doses to which human beings are exposed as well as at higher dose levels in the drinking water. Potassium nitrate was administered to mice at dose levels 90, 200, 500, 700 and 900 ppm for 35 days. There was no difference in the uptake of water in control and treated animals. The amount of nitrate intake/ mouse/day calculated on the basis of water intake in the different groups ranged from 22.5 to 27, 50 to 60, 125 to 150, 175 to 210 and 225 to 270 mg/kg body weight. No changes were evident in the body weight, testicular, epididymal and accessory organ weight at all the dose levels tested, although a decline in sperm count and sperm motility along with an increase in abnormal sperm was noticed at 900 ppm. The activity of marker testicular enzymes, mainly 17-beta hydroxysteroid dehydrogenase (17-betaHSD) and gamma glutamyl transpeptidase (gamma-GT), associated with specific cell types were altered. Histopathological changes including atrophy and disturbed spermatogenesis were observed only at the 900-ppm dose level. In conclusion, we can say that the testicular and spermatotoxic effects are observed only at the highest dose level, which is not likely to be encountered in the drinking water.
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PMID:Testicular and spermatotoxic effect of nitrate in mice. 1204 22


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