Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
Add more filters










Database
Language
Publication year range
2.
J Urol ; 183(4): 1630-5, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20172553

ABSTRACT

PURPOSE: We evaluated the effects of adrenomedullin (Peptide Institute, Minoh-shi, Osaka, Japan) on mediators, including nitric oxide and transforming growth factor-beta, and parameters of renal injury in a murine unilateral ureteral obstruction model. MATERIALS AND METHODS: Three study groups of control, adrenomedullin treated and adrenomedullin plus L-NAME treated BALB/C mice, respectively, underwent left unilateral ureteral obstruction. A 24-hour urine sample was collected to measure urinary NO(2)/NO(3) 1 day before unilateral ureteral obstruction and kidneys were harvested on postoperative day 14. Tubulointerstitial damage markers were evaluated by immunohistochemistry. Tissue transforming growth factor-beta was determined by enzyme-linked immunosorbent assay. Endothelial and inducible nitric oxide synthase immunolocalization was also determined. RESULTS: Urinary NO(2)/NO(3) was significantly higher in the adrenomedullin group than in controls, confirming increased renal nitric oxide production. Immunohistochemistry showed increased endothelial nitric oxide synthase in vascular endothelial cells in the adrenomedullin group but tissue transforming growth factor-beta did not significantly differ in controls vs the adrenomedullin group. Interstitial collagen deposition and fibroblasts in the obstructed kidney were significantly decreased in the adrenomedullin group. The number of leukocytes and apoptotic cells in the obstructed kidney were significantly decreased by adrenomedullin. Renal injury amelioration resulting from adrenomedullin was blunted by the nitric oxide synthase inhibitor L-NAME. CONCLUSIONS: Adrenomedullin increased renal nitric oxide, and suppressed tubular apoptosis, interstitial fibrosis and inflammatory cell infiltration in mice with unilateral ureteral obstruction. The renoprotective peptide adrenomedullin may be useful for that condition.


Subject(s)
Adrenomedullin/pharmacology , Adrenomedullin/therapeutic use , Nitric Oxide/biosynthesis , Renal Insufficiency/drug therapy , Renal Insufficiency/metabolism , Ureteral Obstruction/complications , Animals , Mice , Mice, Inbred BALB C , Renal Insufficiency/etiology , Transforming Growth Factor alpha/biosynthesis
3.
Am J Physiol Renal Physiol ; 291(5): F1033-44, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16757733

ABSTRACT

The gamma-subunit of Na-K-ATPase (FXYD2) and corticosteroid hormone-induced factor (CHIF; FXYD4) are considered pump regulators in kidney tubules. The aim of this study was to expand the information about their locations in the kidney medulla and to evaluate their importance for electrolyte excretion in an animal model. The cellular and subcellular locations and abundances of gamma and CHIF in the medulla of control and sodium-depleted rats were analyzed by immunofluorescence and immunoelectron microscopy and semiquantitative Western blotting. The results showed that antibodies against the gamma-subunit COOH terminus and splice variant gamma(a), but not splice variant gamma(b), labeled intercalated cells, but not principal cells, in the initial part of the inner medullary collecting duct (IMCD1). In subsequent segments (IMCD2 and IMCD3), all principal cells exhibited distinct basolateral labeling for both the gamma-subunit COOH terminus, splice variant gamma(a), and CHIF. Splice variant gamma(b) was abundant in the inner stripe of the outer medulla but absent in the inner medulla (IM). Double labeling by high-resolution immunoelectron microscopy showed close structural association between CHIF and the Na-K-ATPase alpha(1)-subunit in basolateral membranes. The present observations provide new information about the cellular and subcellular locations of gamma and CHIF in the renal medulla and show a new gamma variant in the IM. Extensive NaCl depletion did not induce significant changes in the locations or abundances of the gamma-subunit COOH terminus and CHIF in different kidney zones. We conclude that the unchanged levels of these two FXYD proteins suggest that they are not primary determinants for urine electrolyte composition during NaCl depletion.


Subject(s)
Intracellular Signaling Peptides and Proteins/metabolism , Kidney Medulla/metabolism , Potassium Channels/metabolism , Sodium-Potassium-Exchanging ATPase/metabolism , Animals , Diet, Sodium-Restricted , Fluorescent Antibody Technique , Kidney Medulla/ultrastructure , Male , Microscopy, Immunoelectron , Rats , Rats, Wistar , Sodium Chloride/metabolism , Sodium Chloride/pharmacology
4.
Am J Physiol Renal Physiol ; 288(4): F650-7, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15572522

ABSTRACT

Hypertonicity mediated by chloride upregulates the expression of the gamma-subunit of Na-K-ATPase in cultured cells derived from the murine inner medullary collecting duct (IMCD3; Capasso JM, Rivard CJ, Enomoto LM, and Berl T. Proc Natl Acad Sci USA 100: 6428-6433, 2003). The purpose of this study was to examine the cellular locations and the time course of gamma-subunit expression after long-term adaptation and acute hypertonic challenges induced with different salts. Cells were analyzed by confocal immunofluorescence and immunoelectron microscopy with antibodies against the COOH terminus of the Na-K-ATPase gamma-subunit or the gamma(b) splice variant. Cells grown in 300 mosmol/kgH(2)O showed no immunoreactivity for the gamma-subunit, whereas cells adapted to 600 or 900 mosmol/kgH(2)O demonstrated distinct reactivity located at the plasma membrane of all cells. IMCD3 cell cultures acutely challenged to 550 mosmol/kgH(2)O with sodium chloride or choline chloride showed incorporation of gamma into plasma membrane 12 h after osmotic challenge and distinct membrane staining in approximately 40% of the cells 48 h after osmotic shock. In contrast, challenging the IMCD3 cells to 550 mosmol/kgH(2)O by addition of sodium acetate did not result in expression of the gamma-subunit in the membranes of surviving cells after 48 h. The present results demonstrate that the Na-K-ATPase gamma-subunit becomes incorporated into the basolateral membrane of IMCD3 cells after both acute hyperosmotic challenge and hyperosmotic adaptation. We conclude that the gamma-subunit has an important role in the function of Na-K-ATPase to sustain the cellular cation balance over the plasma membrane in a hypertonic environment.


Subject(s)
Cell Membrane/metabolism , Kidney Medulla/enzymology , Sodium-Potassium-Exchanging ATPase/metabolism , Water-Electrolyte Balance/physiology , Adaptation, Physiological , Animals , Blotting, Western , Cell Polarity , Cells, Cultured , Hypertonic Solutions , Immunohistochemistry , Kidney Medulla/cytology , Mice , Osmotic Pressure
5.
Scand J Urol Nephrol ; 37(3): 265-8, 2003.
Article in English | MEDLINE | ID: mdl-12775288

ABSTRACT

We established a new renal carcinoma cell line that produces parathyroid hormone-related protein (PTHrP) and interleukin-6 in culture. The cellular production of PTHrP was confirmed by Northern blot analysis and immunofluorescence examination. Bone and lung metastases occurred simultaneously 3.5 years after surgery. The patient did not show hypercalcemia at this time, despite the presence of multiple osteolytic metastases. About 7 months after bone metastasis was first shown, serum PTHrP was detected by means of an immunoradiometric assay and the calcium level was found to be elevated to 3.29 mmol/l. The hypercalcemia was successfully controlled by i.v. administration of bisphosphonates.


Subject(s)
Bone Neoplasms/secondary , Carcinoma, Renal Cell/secondary , Hypercalcemia/diagnosis , Kidney Neoplasms/pathology , Peptide Hormones/biosynthesis , Adult , Bone Neoplasms/diagnostic imaging , Carcinoma, Renal Cell/surgery , Diphosphonates/therapeutic use , Follow-Up Studies , Humans , Hypercalcemia/drug therapy , Infusions, Intravenous , Kidney Neoplasms/surgery , Male , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Parathyroid Hormone-Related Protein , Radionuclide Imaging , Risk Assessment
6.
J Biol Chem ; 278(17): 14827-31, 2003 Apr 25.
Article in English | MEDLINE | ID: mdl-12590132

ABSTRACT

Positive cofactor 4 (PC4), originally identified as a transcriptional coactivator, possesses the ability to suppress promoter-driven as well as nonspecific transcription via its DNA binding activity. Previous studies showed that the repressive activity of PC4 on promoter-driven transcription is alleviated by transcription factor TFIIH, possibly through one of its enzymatic activities. Using recombinant TFIIH, we have analyzed the role of TFIIH for alleviating PC4-mediated transcriptional repression and determined that the excision repair cross complementing (ERCC3) helicase activity of TFIIH is the enzymatic activity that alleviates PC4-mediated repression via beta-gamma bond hydrolysis of ATP. In addition, the alleviation does not require either ERCC2 helicase or cyclin-dependent kinase 7 kinase activity. We also show that, as complexed within TFIIH, the cyclin-dependent kinase 7 kinase does not possess the activity to phosphorylate PC4. Thus, TFIIH appears to protect promoters from PC4-mediated repression by relieving the topological constraint imposed by PC4 through the ERCC3 helicase activity rather than by reducing the repressive activity of PC4 via its phosphorylation.


Subject(s)
DNA Helicases/genetics , DNA-Binding Proteins , Repressor Proteins/genetics , Trans-Activators/genetics , Transcription Factors, TFII/genetics , Transcription Factors , Transcription, Genetic , Adenosine Triphosphate/metabolism , Cyclin-Dependent Kinases , Humans , Hydrolysis , Immediate-Early Proteins , Membrane Proteins , Mutation , Phosphorylation , Proteins , Recombinant Proteins , Repressor Proteins/metabolism , Trans-Activators/metabolism , Transcription Factor TFIIH , Xeroderma Pigmentosum Group D Protein , Cyclin-Dependent Kinase-Activating Kinase
SELECTION OF CITATIONS
SEARCH DETAIL
...