Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P41181 (collecting duct)
 5,183 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We investigated the effects of endothelin-1 (ET-1) on Madin-Darby canine kidney (MDCK) cells, a cell line originating from the renal collecting duct. The activity of transepithelial transport was assessed as the rate of dome formation in monolayers grown on solid support. The pH value of the dome fluid (dome pH) was measured by means of pH-selective microelectrodes. Differentiation of monolayer cells was estimated as the peanut-lectin(PNA)-binding capacity of the apical membrane. Confluent monolayers were incubated for 12-72 h in serum-free medium at various concentrations of ET-1. Exposure to 1 nmol/l ET-1 reduced dome formation by a maximum of 41 +/- 8% (n = 4; P less than 0.02) after 24 h. ET-1 (10 nmol/l; 24 h) decreased dome pH from 7.52 +/- 0.02 (n = 53) to 7.36 +/- 0.03 (n = 51; P less than 0.02). Apical application of amiloride (1 mmol/l) reduced dome pH in both ET-1-treated and non-treated domes to essentially the same level, 7.25 +/- 0.03 (n = 19) and 7.23 +/- 0.03 (n = 17) respectively. ET-1 (10 nmol/l; 24 h) reduced PNA-binding capacity by 19 +/- 3% (n = 5; P less than 0.02). Moreover, ET-1 prevented the increase in PNA binding (+ 53 +/- 7%; n = 5) induced by 0.1 mumol/l aldosterone. We conclude that ET-1 inhibits transepithelial transport and PNA binding via inhibition of apical Na+/H+ exchange, thus antagonizing aldosterone action in MDCK cells.
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PMID:Endothelin-1 blunts transepithelial transport and differentiation of Madin-Darby canine kidney cells. 161 24

A battery of seven different horseradish-peroxidase labelled lectins (DBA, PNA, SBA, UEA I, WGA, ConA, LTA) was used to study the distribution of sugar residues in the glycoconjugates along the nephron and the collecting duct of the kidney of Gallus domesticus. As far as the glomerular components are concerned, we have demonstrated that the podocytes and, with a lesser extent, the mesangial cells are characterised by the presence of D-mannose, D-galactose-(beta 1- greater than 3)-N-acetyl-D-galactosamine and sialic acid. The glomerular capillary wall shows the presence of the disaccharide D-galactose-(beta 1- greater than 3)-N-acetyl-D-galactosamine and sialic acid. With regards to the tubules, the proximal tubule, the descending limb of the loop of Henle, the connecting tubule and the collecting one, are characterised by N-acetyl-D-galactosamine, (1- greater than 6)-alpha-L-fucose, D-mannose, N-acetyl-D-galactosamine and D-galactose-(beta 1- greater than 3)-N-acetyl-D-glucosamine. The cells of the connecting and collecting ducts show the presence of intracellular sialic acid, found also as component of the mucous secretion. The ascending limb of the loop of Henle and the distal tubule contain only three saccharidic residues, i.e. (1- greater than 6)-alpha-L-fucose, D-mannose and N-acetyl-D-glucosamine. Lectin histochemistry was also useful to define the saccharidic components of the mucus, which is normally present within the connecting and collecting ducts of the kidney of the birds. The cellular variability of the connecting and the collecting ducts is similar to that found in the kidney of some mammals. Such a variability seems to suggest a possible cell specialization along a single kidney tubule.
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PMID:[Distribution of saccharide residues in glycoconjugates of the kidney in Gallus domesticus using peroxidase-conjugated lectins]. 207 93

The present study is aimed to gain more insight into the histochemical properties of renal oncocytomas. Ten oncocytomas and normal kidneys were investigated using several lectins (peanut agglutinin--PNA, Dolichos biflorus agglutinin--DBA and Ulex europaeus agglutinin--UEA) and antibodies against epithelial membrane antigen (EMA), Tamm-Horsfall glycoprotein (THG) and lysozyme. Lectin histochemistry revealed a characteristic binding pattern in renal oncocytomas, with strong DBA-binding and, in some cases, a weaker staining with UEA apparent in the cytoplasm of the oncocytes. PNA binding sites were evident only after enzymatic cleavage of sialic acid by neuraminidase. Comparative evaluation of normal kidneys exhibiting a strict compartmentalization of saccharide moieties in the various nephron segments revealed a similar binding pattern exclusively in interspersed collecting duct epithelium. This striking resemblance suggests that renal oncocytomas may originate from the collecting duct system. Further support for this assumption has been provided by the demonstration of strong cytoplasmic EMA reactivity in the oncocytes. In normal kidneys prominent labeling for EMA was apparent in the very same interspersed cells of the collecting ducts. THG and lysozyme failed to react in renal oncocytomas. In accordance with observations recently reported in the literature, these results clearly favor a histogenetic origin of renal oncocytomas from the collecting duct epithelium.
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PMID:Renal oncocytoma. II. Lectin and immunohistochemical features indicating an origin from the collecting duct. 246 70

In recent years histochemical methods using lectins with diverse carbohydrate binding specificities have proved useful tools for studying the distribution pattern of intracellular and pericellular glycoconjugates at the tissue level. Several studies of human kidneys have shown that the binding sites for certain lectins are strictly confined to various parts of the nephron. This allows the use of lectins as markers for the particular segments. The glomeruli exhibit abundant sialoglycoproteins at the free surface coat of the podocytes as detected by PNA after sialidase representing a major component of the filtration barrier; neoplastic podocytes of glomeruloid bodies in nephroblastomas as well revealed an intense lectin binding despite failing any vascularization. The lectin binding pattern of renal carcinomas varies within a wide range depending on their histological growth pattern. Whereas most renal carcinomas of clear and granular cell type rarely displayed a slight reactivity with lectins at the cell surface and at the luminal aspect of tubulopapillary tumors, a sub-group of carcinomas named chromophobe type exhibited a strong cytoplasmic staining with DBA and PNA after sialidase. Comparative evaluation of normal kidneys revealed an identical binding pattern exclusively in the intercalated cells of the collecting ducts probably indicating a histogenetic origin of these tumors from the collecting duct epithelium. This assumption derives further support from the detection of precursor lesions rarely detected in normal and tumor-bearing kidneys exhibiting the same lectin binding pattern. In accordance with recent observations in the literature the disclosure of a similar lectin binding pattern in renal oncocytomas and their precursor lesions exhibiting oncocytic transformation clearly favors the assumption of an identical histogenetic origin. On the other hand, few cases of a carcinoma mimicking collecting duct epithelium exhibited a broader lectin binding pattern revealing evidence of secretory activity; the histochemical similarities between this unusual carcinoma and transitional cell carcinoma confirmed the suggested origin from the ducts of Bellini. In conclusion, lectin histochemistry may be a useful tool for estimating the characteristics of renal tumors and elucidating their histogenesis.
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PMID:[Lectin histochemistry in the kidney and renal tumors]. 248 19

Distribution of lectin-binding sites in adult and developing mouse kidney was studied with fluorochrome- and peroxidase-coupled lectins. Effects of fixation methods on lectin-binding patterns were also compared. Un-induced mesenchymal cells and ureter bud of the early metanephros reacted with Concanavalin A, Lens culinaris, Ricinus communis I, and wheat germ agglutinins, whereas binding sites for both soybean and peanut (PNA) agglutinins were seen only in ureter bud tissue. On induction, PNA positivity rapidly appeared in the induced, condensed areas of the metanephrogenic mesenchyme. Early glomeruli expressed heterogeneously terminal galactosyl and N-acetylgalactosaminyl moieties in the podocytes. Later, these sites disappeared and were apparently covered by sialic acids. Endothelia also displayed a comparable sialylation of terminal saccharide moieties during maturation. Binding sites for many of the above lectins were also found in the developing proximal and distal tubules. Terminal fucosyl residues, characteristic of mature proximal tubules, appeared during day 13 of development. Dolichos biflorus agglutinin reactivity, typically seen in the collecting ducts, appeared by day 13. Griffonia simplicifolia-I-B4 isolectin reactivity was exclusively localized to endothelial in adult kidney cortex, but in embryonic kidneys reactivity with collecting duct and podocytes was also seen. These results suggest that the compartmentalized expression of cell glycoconjugates in adult mouse kidney is acquired in a sequential manner during development. Such sequential appearance of the mature glycosylation pattern probably reflects functional maturation of the nephron.
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PMID:Changes in the glycosylation pattern during embryonic development of mouse kidney as revealed with lectin conjugates. 379 9

Long-Evans (Eker) rats carry a mutation that predisposes them to develop spontaneous renal cell tumors of two morphologic patterns: solid chromophilic masses or cystic lesions lined by eosinophilic cells. Previous studies have suggested that these tumors arise from the proximal tubules. In the present study, lectin-binding characteristics and cytokeratin expression of various stages of hereditary rat renal epithelial neoplasia were examined to localize the portion of the nephron from which tumors arise. Lectin-binding histochemistry has been used as a marker of cell surface glycoprotein expression, thought to be important in the differentiation of benign from malignant epithelial lesions and in the determination of their cell of origin. The presence or absence of keratin intermediate filaments in the rat nephron has been used to identify nephron segments. The polyclonal antibody to high- and low-molecular-weight cytokeratin stained the cells of the collecting ducts but not the proximal or distal tubules. Binding to the proximal tubules by the lectins Conavalia ensiformis (Con A), Dolichas biflorus, Ricinus communis (RCA-1), and Triticum vulgare and to the distal tubules by Con A, RCA-1, Arachis hypogaea (PNA) with and without neuraminidase, and the antibody for cytokeratins was demonstrated. The lectin binding and cytokeratin staining patterns of rat hereditary renal cell carcinoma, adenoma and the preneoplastic lesions of atypical tubules and hyperplasias suggest that cystic adenomas arise from the distal nephron, principally the collecting duct, whereas the solid atypical tubules, hyperplasias, and adenomas arise from the proximal nephron, principally the proximal tubule.
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PMID:Preneoplastic and neoplastic lesions of rat hereditary renal cell tumors express markers of proximal and distal nephron. 748 12

Morphological and histoenzymological differences have been observed between intercalated and principal cells of the quail Coturnix coturnix japonica collecting ducts. The present study was designed to shed light on the lectin affinity of the collecting duct cells within cortex and medulla by the use of HRP-labelled lectins combined with glycosidase degradation. Binding of PNA and RCA-I lectins consequent to enzymatic release of sialic acid revealed abundant sialylated carbohydrate moieties within the principal cell cytoplasm. This characteristic binding pattern differed considerably from the staining observed in the intercalated cells. Interesting information also emerged about the presence of sialoglycoconjugates having the terminal disaccharide sialic acid-beta-N-acetylgalactosamine originating from the increased SBA binding and the unmodified DBA labelling after removal of sialic acid. Sequential degradation by sialidase/beta-galactosidase followed by incubation with DBA offered the possibility to suspect that the receptor sugar for the penultimate beta-galactose may be N-acetylgalactosamine. Conversely, we were not able to define the accept sugar for penultimate beta-GalNAc owing to the lack of availability of beta-N-acetylgalactosaminidase enzyme. When although further studies are clearly needed to elucidate the physiological role of the cellular sialoglycoconjugates detected, the present results already provide valuable insight into the carbohydrate composition of intercalated and principal cells in the quail collecting ducts.
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PMID:Mosaic lectin labelling in the quail collecting ducts. 754 Dec 64

Madin-Darby canine kidney (MDCK) cells originate from the renal collecting duct and consist of different cell subtypes. We cloned two MDCK cell subtypes denominated as C7 and C11 with different morphology and different function. The two clones maintained their functional differences after cloning. C7 monolayers exhibit a high transepithelial resistance (Rte = 5648 +/- 206 omega.cm2, n = 20) and secrete K+ (delta K+ = 1.31 +/- 0.08 mmol/l, n = 10) into the apical medium. C11 monolayers display a low Rte (330 +/- 52 omega.cm2, n = 20) and secrete Cl- (delta Cl- = 16.9 +/- 1.8 mmol/l, n = 10) into the apical medium. Aldosterone (1 mumol/l) stimulates K+ secretion (delta K+ of 3.58 +/- 0.11 mmol/l, n = 7) in C7 cells and H+ secretion in C11 cells (delta pH = 0.060 +/- 0.007, n = 10). Aldosterone-induced stimulation of K+ secretion is inhibited by apical application of amiloride (1 mumol/l). cAMP stimulates H+ secretion in C11 cells (delta pH = -0.068 +/- 0.004, n = 10). Furthermore, C7 cells are peanut-lectin(PNA)-negative and exhibit an intracellular pH of 7.39 +/- 0.05 (n = 7), whereas C11 cells maintain intracellular pH at 7.16 +/- 0.05 (n = 8) and a major fraction of cells is PNA positive. We conclude that we have cloned two subtypes of MDCK cells which stably express different functional characteristics. The C7 subtype resembles principal cells (PC) of the renal collecting duct, whereas the C11 subtype resembles intercalated cells (ICC) of the renal collecting duct.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Characterization of two MDCK-cell subtypes as a model system to study principal cell and intercalated cell properties. 797 Nov 72

The Madin-Darby canine kidney (MDCK) cell line has been proposed as a model for studying intercalated (IC) cells of the renal cortical collecting duct. The IC cells are characterized by peanut lectin (PNA) binding capacity, carbonic anhydrase (CA) activity and Cl(-)-HCO3- exchange mediated by a band 3-related protein. It has been suggested that these properties are also expressed in MDCK cells. So far however, the nature of the specific protein involved in Cl(-)-HCO3- exchange, the type of CA isozyme and the relationship between these two characteristics and PNA binding, have not been investigated in MDCK cells by immunocytochemical methods. Using two antibodies raised against human erythrocyte band 3 protein and two against human erythrocyte CA I and II isozymes, our study provides evidence that a protein related to band 3 is expressed in about 5% of cultured MDCK cells; these band 3-positive cells do not bind PNA and are not reactive for CAI or CAII. About 30% of the MDCK cells bind PNA, two-thirds of which are also CAII-positive. A majority (about 65%) of MDCK cells is not reactive for the three markers used; their density is increased after incubation with aldosterone. These data indicate (i) that the Cl(-)-HCO3- exchange of the MDCK cells could be related to human erythrocyte band 3, (ii) that the CA activity of the MDCK cell line bears antigenic identity with the erythrocyte CA II isozyme and (iii) that the latter is always co-localized with PNA binding.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Subtypes of Madin-Darby canine kidney (MDCK) cells defined by immunocytochemistry: further evidence for properties of renal collecting duct cells. 808 17

Renal oncocytoma is a benign tumour of renal tubular origin; oncocytes are transformed epithelial cells rich in mitochondria, probably representing senescent degenerative cellular changes. Most of renal oncocytomas usually follow a benign clinical course and partial nephrectomy or enucleation has been advocated as curative. By immunohistological staining of tissue sections using monoclonal antibodies (DBA, SBA, PNA, UEA, Cytocheratine), we can suppose the histogenetic origin of renal oncocytomas from a region other than the proximal tubular epithelium, and in particular from the collecting duct epithelium. We believe that it is most important to perform flow cytometry to study the chromosomal pattern of the tumour, once intra-operative frozen sections have advanced the suspicion of renal oncocytoma; if oncocytic cells show a diploid pattern, and the tumour mass is well circumscribed and has not an excessive diameter, we favour renal sparing surgery.
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PMID:Renal oncocytoma. Pathological evaluation and clinical implications. 871 69


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