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)

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

Intracellular localization of two molecular species of calpain (Ca2+-dependent cysteine proteinase) was studied by immunocyto- and histochemical methods employing antibodies strictly monospecific for the respective antigens. Apparent immunological cross-reactivity between the larger subunits of calpain I (low Ca2+-requiring form) and calpain II (high Ca2+-requiring form) was calculated to be 15-17%, and two steps of affinity chromatography were needed to obtain antibodies which can discriminate between the two proteases. Indirect immunofluorescent staining of cultured PK 15 cells revealed diffuse staining of the cytoplasm with both antibodies against calpain I and calpain II. Preincubation with Ca2+-ionophore had no effect on the staining patterns. Sections of porcine kidney were stained by the avidin-biotinylated peroxidase complex method. The proximal and distal tubules and collecting duct were stained, but the glomerulus, macula densa, and vascular vessels were not stained by either anti-calpain I or anti-calpain II antibodies.
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PMID:Intracellular localization of two distinct Ca2+-proteases (calpain I and calpain II) as demonstrated by using discriminative antibodies. 608 54

Distribution of glycoconjugates in different areas of the rat kidney was studied by light and electron microscopy using six different horseradish peroxidase-labeled lectins. Glomeruli and brush borders of the proximal tubules reacted differently to these lectins, which indicated differences in the carbohydrate compositions of those regions. The ascending limb of Henle's loop (ALH) had strong binding sites for peanut agglutinin (PNA) and soybean agglutinin (SBA). Dolichos biflorus agglutinin (DBA) did not stain the cells of ALH but did stain those of distal convoluted tubules (DCT). DBA is a good marker for distinguishing ALH from DCT. DBA, PNA, and SBA were also good markers of the collecting duct. Ricinus communis agglutinin (RCA-1) and wheat germ agglutinin (WGA) diffusely stained the various components of different parts of the kidney.
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PMID:Distribution of glycoconjugates in the kidney studied by use of labeled lectins. 618 20

Nerve growth factor (NGF) was localized in the submandibular, sublingual, and parotid salivary glands of male and female diabetic mice and their normal littermates by immunoperoxidase staining using p-phenylenediamine-pyrocatechol as a chromogen for the cytochemical demonstration of peroxidase activity. In the normal male submandibular gland, immunoreactive NGF was localized in the apical regions of granular, intercalated and collecting duct cells, while in the normal female submandibular gland, NGF was present throughout the cytoplasm of granular duct cells. The localization of NGF in the diabetic male and female submandibular glands was similar and resembled that of the normal female. NGF immunoreactivity was also observed in the striated duct cells in the sublingual and parotid glands of all four types of mice. The sympathetic innervation of the submandibular glands of normal and diabetic mice was demonstrated using glyoxylic acid-induced histofluorescence. The pattern of sympathetic innervation and the intensity of catecholamine fluorescence was consistently different in the four types of mice. In the normal male submandibular gland the fluorescence was very intense, particularly in nerves adjacent to the granular ducts. In the normal female submandibular gland, the fluorescence was weak, while in the diabetic male and female the fluorescence was moderate. The correlation between the intensity of the immunocytochemical staining for NGF and the catecholamine fluorescence adjacent to the granular ducts suggests a trophic influence of the NGF-containing granular ducts on their sympathetic innervation.
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PMID:Immunocytochemical demonstration of nerve growth factor and histofluorescence of catecholaminergic nerves in the salivary glands of diabetic mice. 703 96

The anatomical relationship between kallikrein and renin in the rat kidney was investigated immunohistochemically by the peroxidase-antiperoxidase method. Kallikrein was localized to the convoluted distal tubule, starting at a point, distal to the juxtaglomerular apparatus, where the thick ascending limb of loop of Henle transformed into the convoluted distal tubule. The thick ascending limb was identified by its content of uromucoid (Tamm-Horsfall glycoprotein). Kallikrein was never observed within the juxtaglomerular apparatus itself. The kallikrein-containing tubule ended where the distal tubule submerged into the collecting duct. Renin was found in epitheloid cells of the afferent arteriole. When neighboring sections were stained for kallikrein and renin, respectively, no close anatomical relationship was observed between the kallikrein-containing and the renin-containing structures.
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PMID:Localization of kallikrein in the rat kidney and its anatomical relationship to renin. 703 45

In order to estimate the usefulness of lectins in the study of the functional segmentation of the nephron, the sites of binding of four lectins were identified in the rabbit kidney. Lectin-peroxidase conjugates were applied to unfixed cryostat sections. The bound conjugates were stained with 3,3'-diaminobenzidine for light microscopical observation. Each lectin has a specific binding pattern along the nephron. The patterns generally fit in with the segmentation of the nephron established by conventional histology. However, in the proximal tubule and in the thick ascending limb the lectin binding suggests functional transitions in histologically homogeneous tubular portions. In contrast to the other cell types of the connecting tubule and of the collecting duct the intercalated cells bind two lectins at their luminal membrane. Segmental differences in the lectin affinity of the basement membrane suggest that this structure has not only mechanical functions. The binding of lectins to luminal membranes in some segments indicate the possibility to use lectins for the separation of particular cell types and for modification of the transport properties of their membranes.
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PMID:The cellular specificity of lectin binding in the kidney. II. A light microscopical study in the rabbit. 710 28

The kallikrein-kinin system is involved in the inflammatory process, in blood pressure regulation, and in renal homeostasis. The presence of kallikreins, kininogens, and kinins in renal tissues and fluids is well established; however, the occurrence and distribution of the bradykinin (B2) receptor in the kidney are unknown. Using chemically cross-linked conjugates of bovine serum albumin and the B2 agonist bradykinin or the potent B2 antagonist HOE140, followed by antibodies to the respective ligand and the peroxidase-anti-peroxidase system, we were able to detect the B2 receptor. The receptor has been found in straight portions of the proximal tubules, in distal straight tubules, in connecting tubules, and in collecting ducts of rat kidney. The staining patterns produced by the ligand conjugate-antiligand approach are in agreement with those obtained by conventional autoradiography using [125I]-Tyr0-bradykinin. Immunocytochemical localization of B2 receptor by antipeptide antibodies to the receptor confirmed these findings and demonstrated the presence of B2 receptor in the basal infoldings and luminal membranes of the tubule cells, and in smooth muscle cells of the cortical radial artery and of afferent arterioles. Co-localization of the B2 receptor with kallikrein and kininogens in connecting tubule cell and collecting duct cell layers, respectively, provides a structural basis for the hypothesized physiological functions of the kallikrein-kinin system in the kidney.
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PMID:Probing for the bradykinin B2 receptor in rat kidney by anti-peptide and anti-ligand antibodies. 782 71

Several lines of evidence suggest that taurine acts as an organic osmolyte in the kidney. We investigated the cellular and subcellular distribution of this amino acid in rat renal tubule cells. Semi- and ultrathin sections of plastic-embedded rat kidney were incubated with an antiserum against conjugated taurine, using peroxidase-antiperoxidase and immunogold procedures, respectively. Extensive control tests confirmed the selectivity of the antiserum. Our immunocytochemical preparations revealed a highly differentiated labeling pattern. Strong labeling (judged visually or by computer-aided calculation of gold particle densities) was found in collecting duct cells throughout cortex and medulla, in proximal straight tubule cells, and in cells of the descending thin limbs of Henle's loop. Intermediate gold particle densities occurred in proximal convoluted tubule cells and intercalated cells of the collecting ducts (the gold particle in the latter being 30% of that in the collecting duct cells). The distal convoluted tubules, and thick and thin ascending limbs were almost immunonegative. It cannot be excluded that the proportion of free taurine that is retained by the fixative varies somewhat among the different cell types. Yet the highly differentiated labeling pattern that was obtained suggests that taurine is heterogeneously distributed among different populations of tubule cells, and that its level varies substantially even among cells that are exposed to the same osmotic stress.
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PMID:Light- and electronmicroscopic distribution of taurine, an organic osmolyte, in rat renal tubule cells. 812 97

Structurally and functionally distinct populations of intercalated cells have been described in the collecting duct of both rat and rabbit. However, little is known about these cells in the mouse kidney. The study presented here examines ultrastructural and immunological characteristics of different types of intercalated cells in the mouse. Kidneys of two strains of normal female mice, C57BL/6 and IBR, were preserved by in vivo perfusion with 1% glutaraldehyde or paraformaldehyde-picric acid fixatives and processed for morphological evaluation or light and electron microscopic immunohistochemistry, respectively. The avidin-biotin-horseradish peroxidase procedure was performed on was sections using antibodies against carbonic anhydrase II, H+ -ATPase and Band 3 protein. Immunogold cytochemistry was performed on Lowicryl sections using antibodies to H+ -ATPase and Band 3 protein. Colocalization of H+ -ATPase and Band 3 protein was performed by double labeling using an immunogold technique with silver enhancement. Intercalated cells identified by positive staining for H+ -ATPase and carbonic anhydrase II constituted 35% to 40% of all cells in the connecting tubule (CNT), cortical collecting duct (CCD), and outer medullary collecting duct (OMCD). Type A intercalated cells identified by positive Band 3 staining constituted 16%, 24%, and 33% of the total cell population in the CNT, CCD, and OMCD, respectively. Electron microscopy and immunogold cytochemistry demonstrated three distinct populations of intercalated cells. Type A intercalated cells with apical H+ -ATPase and basolateral Band 3 immunoreactivity were present in all segments examined, and had prominent apical microprojections and characteristic tubulovesicular structures beneath the apical surface, both coated with studs on the cytoplasmic face. Type B intercalated cells with basolateral and cytoplasmic H+-ATPase and no Band 3 immunoreactivity were most frequently observed in the initial collecting tubule, but were present also in the CNT and early CCD. Type B intercalated cells had a fairly smooth apical surface, a gray zone free of organelles beneath the apical plasma membrane, and small cytoplasmic vesicles without studs throughout the cell. A third type of intercalated cell with apical and cytoplasmic H+-ATPase, but no basolateral Band 3 protein, was observed exclusively in the CNT and the initial collecting tubule. This type of cell was large, with numerous mitochondria, and vesicles coated with studs were present throughout the cell. It resembled a third type of intercalated cell described previously in the rat. It is concluded that three morphologically and immunologically distinct types of intercalated cells are present in the mouse kidney.
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PMID:Identification of distinct subpopulations of intercalated cells in the mouse collecting duct. 878 96

Increased renal production of vasodilator mediators like kinins would counteract the vasospasm of pre-eclampsia. This study examines the cellular localisation of tissue kallikrein (TK), the potent kinin forming enzyme within the nephron of patients with early onset pre-eclampsia. Using the peroxidase-antiperoxidase immunoenzyme complex, TK was immunolocalised in the principal cells of the distal connecting tubule and the cortical collecting duct cells of the distal nephron of control tissue. Moderate reactivity was observed in the epithelial cells lining the Bowmans capsule. In early onset pre-eclampsia, TK was additionally localised in the proximal tubule cells, however, the intensity of reactivity was reduced when compared to that of the distal tubule cells. In patients with hypertension of pregnancy, the occurrence of TK in the proximal tubule suggests either gene induction or emiocytosis of TK.
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PMID:Localisation of tissue kallikrein in the kidney of black African women with early onset pre-eclampsia: a pilot study. 922 54


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