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Query: UNIPROT:P41181 (collecting duct)
 5,183 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A total of 49 dimethylnitrosamine (DMN)-induced rat renal cell tumors were analyzed and classified cytomorphologically at an early stage of development. Of these, 17 were basophilic-tubular tumors, two of which showed a direct transition to proximal tubules of the P3-segment; 21 lesions were vacuolated and contained glycogen; these were defined cytomorphologically as a separate tumor type the histogenetic derivation of which from the collecting duct system was established by documentation of a direct transition. Morphological similarities point to the lipid-storing variant of the basophilic tumor, but a carcinoma of the ducts of Bellini is another possible human equivalent of this tumor type. Another seven lesions were clear and granular cell tumors. In two of these a direct transition from the collecting duct system was found, thus confirming that this only recently established origin of experimentally induced rat renal clear cell tumors also applies to lesions induced by DMN. The proliferation kinetics of DMN-induced lesions were studied in autoradiograms after pulse-labeling with tritiated thymidine. The basal proliferation of these early tumor stages displayed a marked proliferative advantage over the normal parenchyma. The lesions were still subject to physiological growth stimulation as determined by 3H-TdR-continuous-labeling with osmotic mini-pumps following unilateral nephrectomy. However, compared with normal kidney parenchyma, the 3H-TdR-labeling index of the lesions was even higher indicating a response modification during early neoplasia.
Virchows Arch B Cell Pathol Incl Mol Pathol 1992
PMID:Morphology and proliferation kinetics of early tumor stages induced by dimethylnitrosamine in rat kidneys. 135 13

The ontogenesis of vasopressin receptors in the rat collecting duct was studied by measuring the binding of [1-(beta-mercapto-beta,beta-cyclopentamethylenepropionic acid),2-O-methyltyrosine,4-threonine,8-ornithine,9-125I-tyrosylamide+ ++]-vasotocin (125I-d(CH2)5[Tyr(Me)2,Thr4,Tyr-NH(9)2]-OVT) to isolated cortical collecting ducts (CCD), outer medullary collecting ducts (OMCD) and inner medullary collecting ducts (IMCD) microdissected from collagenase-treated kidneys of 2- to 34-day-old rats and adult animals. The stereospecificity for recognition of a series of seven vasopressin structural analogues by CCD and OMCD receptors reveals that the labeled binding sites identified in 11- to 16-day-old and adult rats are homologous respectively and contain a major population of V2 type and a minor population of V1a type of vasopressin receptors. At all postnatal stages examined, the receptor density (expressed as 10(-18) mol radioligand bound per square millimeter tubular outer surface area) decreases gradually from the CCD to the IMCD. For the three segments, the numbers of receptors detected remained constant during the first 2 weeks after birth and increased sharply after 20 days to reach the corresponding adult levels during the fifth week.
Mol Cell Endocrinol 1992 Aug
PMID:Postnatal ontogenesis of vasopressin receptors in the rat collecting duct. 138 71

The present study was designed to shed light on the extraordinary histochemical properties of the chromophobe cell renal carcinoma detected by Hale's colloidal iron reaction. Special emphasis was laid on the lectin histochemical analysis of cytoplasmic glycoconjugates. Binding of peanut agglutinin (PNA) and Erythrina cristagalli agglutinin (ECA) after enzymatic release of sialic acid and direct binding of Dolichos biflorus agglutinin (DBA) correlates well with the expression of binding sites for Sambucus nigra agglutinin (SNA) and Maackia amurensis agglutinin (MAA) revealing abundant sialylated carbohydrate moieties within the cytoplasm. This characteristic binding pattern differs considerably from the faint staining observed in the majority of other renal carcinomas, thus confirming that the chromophobe cell renal carcinoma is a distinct entity. However, the lectin binding pattern of renal oncocytoma obviously resembles that of chromophobe carcinoma indicating a close relationship between these renal tumors. Detailed analysis of adjacent renal parenchyma revealed a lectin binding pattern quite similar to that described in the chromophobe carcinomas exclusively in the intercalated cells lining the collecting duct. This finding suggests that the chromophobe cell renal carcinoma originates from the collecting duct epithelium. The detection of small complexes consisting of altered epithelia which display the morphological characteristics of chromophobe carcinoma and the histochemical properties of intercalated cells probably indicates the emergence of preneoplastic lesions preceding the development of chromophobe carcinoma. Even though further studies are clearly needed to elucidate the physiological role of the cellular glycoconjugates detected, the present results already provide valuable insight into the histogenesis and pathogenesis of the chromophobe cell renal carcinoma.
Virchows Arch B Cell Pathol Incl Mol Pathol 1991
PMID:Sialylated glycoconjugates in chromophobe cell renal carcinoma compared with other renal cell tumors. Indication of its development from the collecting duct epithelium. 168 20

Recent work has demonstrated that alpha 1-adrenergic receptors are composed of at least two subtypes, termed alpha 1a and alpha 1b. It has been proposed that these subtypes may be linked to distinct second messenger systems. In the current studies, we have compared the properties of alpha 1-adrenergic receptors in rat renal cortical membranes with those in MDCK-D1 cells, a clonal cell line derived from distal tubule/collecting duct. Competitive binding studies with [3H]prazosin and compounds [5-methylurapidil, (+)-niguldipine, WB4101, and oxymetazoline] that distinguish high affinity (alpha 1a) and low affinity (alpha 1b) sites indicated that rat renal cortical membranes contain about 50% of each class of site. In contrast, MDCK-D1 cells contained a single population of low affinity sites. 5-Methylurapidil, but not the other compounds, recognized binding sites in these cells with a substantially lower affinity than has been observed for the low affinity site in other tissues and in parallel studies with renal cortical membranes. [3H]Prazosin binding sites in these cells, as well as alpha 1-adrenergic receptor-mediated arachidonic acid release and phosphoinositide and phosphatidylcholine hydrolysis, were sensitive to inactivation by chloroethylclonidine (IC50 approximately 0.7 microM), as expected for alpha 1b receptors. However, alpha 1-adrenergic receptors of MDCK-D1 cells required extracellular calcium for biological response, unlike what has been hypothesized for the alpha 1b receptor subtype. These data indicate that the population of alpha 1-adrenergic receptors of distal tubule/collecting duct cells likely consists of receptors of the alpha 1b subtype. The low affinity binding of 5-methylurapidil and the requirement for extracellular calcium for biological response in these cells suggest that this receptor may not be identical to the alpha 1b receptor that has been observed in other systems.
Mol Pharmacol 1991 Mar
PMID:Renal alpha 1-adrenergic receptor subtypes: MDCK-D1 cells, but not rat cortical membranes possess a single population of receptors. 184 62

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.
Virchows Arch B Cell Pathol Incl Mol Pathol 1988
PMID:Renal oncocytoma. II. Lectin and immunohistochemical features indicating an origin from the collecting duct. 246 70

Renal oncocytoma is a distinct type of epithelial tumor said to arise from the collecting duct system. Here we show that in nine of ten oncocytomas the tumor cells expressed an analog of the erythrocyte anion exchanger band 3. In the normal kidney band 3 is confined to the basolateral surface of the majority of intercalated cells which comprise up to 50% of the cortical collecting duct epithelium. Carbonic anhydrase c is another protein abundant in intercalated cells, and this was also expressed in six of the ten oncocytomas investigated. Immunoreactivity specific for band 3 and carbonic anhydrase c was not detected in any of the 20 renal cell carcinomas examined. At favourable section planes direct transitions between normal collecting ducts and oncocytic tubules were observed. These findings suggest that oncocytomas may develop from intercalated cells of the collecting duct epithelium.
Virchows Arch B Cell Pathol Incl Mol Pathol 1988
PMID:Intercalated cells as a probable source for the development of renal oncocytoma. 246 71

In the present study we have examined ten cases of the chromophobe type renal cell carcinoma. This type of tumor is distinguished from the other carcinomas of the kidney with light cytoplasm (formerly called "hypernephroid") by (a) a positive Hale's iron colloid stain of the cytoplasm, (b) the occurrence of numerous invaginated vesicles within the cytoplasm that resemble the invaginated vesicles of intercalated cells of the collecting duct system, and (c) a positive immunoreaction of both the plasma membrane and the cytoplasm with antibodies to the epithelial membrane antigen (EMA) and carbonic anhydrase C (CAC), respectively. Unlike oncocytomas, which also express CAC and EMA, the chromophobe renal cell carcinoma does not express the erythrocyte anion exchanger band 3. These findings strongly indicate that chromophobe renal cell carcinomas as well as oncocytomas of the kidney are histogenetically related to the two populations of intercalated cells of the collecting duct system. Thus, both tumors represent examples of renal tumors which disprove the broadly accepted hypothesis that all epithelial tumors of the kidney are histogenetically related to the proximal tubule.
Virchows Arch B Cell Pathol Incl Mol Pathol 1989
PMID:The human chromophobe cell renal carcinoma: its probable relation to intercalated cells of the collecting duct. 256 18

The histo- and cytogenesis of two cases of renal oncocytoma have been studied by cytomorphological and cytochemical methods. Transitions from collecting ducts into oncocytic tubules were observed at the light and electron microscopic levels. The fine structure of the oncocytes in tubules and tumors is described in detail. Cytochemically, the oncocytic tubules and oncocytomas share many characteristics with the distal nephron, especially the collecting ducts. A striking difference is the enhanced activity of succinic dehydrogenase which corresponds to the increase in the number of mitochondria in oncocytes. All the results suggest that renal oncocytoma originates from the collecting duct.
Virchows Arch B Cell Pathol Incl Mol Pathol 1987
PMID:Renal oncocytoma: origin from the collecting duct. 288 61

The ultrastructure of superficial distal nephron segments was analyzed after precise localization of tubule cross sections using computer-assisted three-dimensional reconstructions. Five systems of tubules, each with three interconnected distal tubules, were reconstructed and the lengths of the post macula densa segment of the distal straight tubule (DST), the distal convoluted tubule (DCT), the connecting tubule (CNT), and the initial collecting tubule (ICT) were determined. Each cortical collecting duct (CCD) was in continuity with only one tubule in contact with the renal capsule. In three of the five reconstructions, the two nonsubcapsular tubules fused and had a common connection to the subcapsular tubule. The length, between the macula densa (MD) and the confluence, of subcapsular tubules (2.68 +/- 0.15 mm) significantly exceeded the length of tubules not in contact with the renal capsule (2.05 +/- 0.10 mm). This difference was mainly due to a longer ICT in subcapsular tubules. Subcapsular tubules always contacted the renal capsule in the early DCT and often again in the ICT. Cells in the early DCT showed more microvilli on the luminal surface and more infoldings of basolateral membranes than cells in the late DCT. The ultrastructure of intercalated cells (I cells) varied within a range of different manifestations and the ultrastructural variation of I cells was similar in all the analyzed tubule segments. Connecting tubule cells and principal cells were similar in ultrastructure in all tubule segments and cortical levels analyzed.
J Ultrastruct Mol Struct Res 1988 May
PMID:Ultrastructure of three-dimensionally localized distal nephron segments in superficial cortex of the rat kidney. 317 Dec 50

This ultrastructural investigation on renal collecting duct cells and hepatocytes of rats deals with the question of whether or not lipid-storage lysosomes as induced by cationic amphiphilic compounds retain their ability to fuse with autophagosomes/autolysosomes. These were recognized by their glycogen content which was made to persist by means of acarbose, an inhibitor of lysosomal alpha-glucosidase. To induce lipidosis, rats were pretreated for several weeks with chloroquine or chlorphentermine; they then received combined treatment with the lipidosis-inducing drug plus acarbose. In renal collecting duct cells, mixed storage lysosomes displaying the features of both lipidosis and glycogenosis were found to predominate, indicating that fusion between lipid-laden lysosomes and glycogen-containing autophagosomes/autolysosomes was efficient. Hepatocytes also displayed some mixed storage lysosomes; these were, however, regularly accompanied, within a given hepatocyte, by greater numbers of pure lipidosis-related inclusions and pure glycogen vacuoles. This observation indicates that in hepatocytes lipid-storage lysosomes were rather reluctant to fuse, thus displaying a feature of telolysosomes which are no longer capable of participating in cellular digestion.
Exp Mol Pathol 1987 Feb
PMID:Fusion of storage lysosomes in experimental lipidosis and glycogenosis. 346 80


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