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)

Most renal cell carcinomas (RCC) are composed of clear cells with sinusoid-like vasculatures and originate from the proximal tubule. On the other hand, collecting duct carcinoma (CDC) and chromophobe RCC are thought to originate from the lower nephron. In the present study, we present a case of unusual RCC. The patient was a 68-year-old Japanese woman who had developed general fatigue with hematuria. Computed tomography revealed a left renal tumor suggesting sarcoma. The resected tumor was located in the renal parenchyma, measuring 12 x 10 x 8 cm in size. Histologically, the tumor consisted principally of cuboidal cells forming parallel or radiating arrays, continuous with the spindle-shaped cells. Most parts of the tumor showed hemorrhagic necrosis. Immunohistochemically, tumor cells were positive for high molecular weight cytokeratins, vinculin, vimentin, CD15 and epithelial membrane antigen, and showed affinities with some kinds of lectins. N- and E-cadherins and beta-catenin were diffusely positive in tumor cells. Nuclear positivity for Ki-67 and p53 protein were approximately 2.0 and 1.7%, respectively. Considering its morphological and histochemical natures, this tumor is considered to have originated from the lower nephron, which is unique for a tumor of low-grade malignancy.
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PMID:Low-grade renal cell carcinoma arising from the lower nephron: a case report with immunohistochemical, histochemical and ultrastructural studies. 1184 69

Acute hormonal regulation of the epithelial sodium channel (ENaC) in tight epithelia increases transcellular Na(+) transport via trafficking of intracellular channels to the apical surface. The fate of the channels removed from the apical surface following agonist washout is less clear. By repetitively stimulating polarized mouse cortical collecting duct (mCCD, (MPK)CCD(14)) epithelia, we evaluated the hypothesis that ENaC recycles through an intracellular pool to be available for reinsertion into the apical membrane. Short circuit current (I(SC)), membrane capacitance (C(T)), and conductance (G(T)) were recorded from mCCD epithelia mounted in modified Ussing chambers. Surface biotinylation of ENaC demonstrated an increase in channel number in the apical membrane following cAMP stimulation. This increase was accompanied by a 83 +/- 6% (n = 31) increase in I(SC) and a 15.3 +/- 1.5% (n = 15) increase in C(T). Selective membrane permeabilization demonstrated that the C(T) increase was due to an increase in apical membrane capacitance. I(SC) and C(T) declined to basal levels on stimulus washout. Repetitive cAMP stimulation and washout (approximately 1 h each cycle) resulted in response fatigue; DeltaI(SC) decreased approximately 10% per stimulation-recovery cycle. When channel production was blocked by cycloheximide, DeltaI(SC) decreased approximately 15% per stimulation cycle, indicating that newly synthesized ENaC contributed a relatively small fraction of the channels mobilized to the apical membrane. Selective block of surface ENaC by benzamil demonstrated that channels inserted from a subapical pool made up >90% of the stimulated I(SC), and that on restimulation a large proportion of channels retrieved from the apical surface were reinserted into the apical membrane. Channel recycling was disrupted by brefeldin A, which inhibited ENaC exocytosis, by chloroquine, which inhibited ENaC endocytosis and recycling, and by latrunculin A, which blocked ENaC exocytosis. A compartment model featuring channel populations in the apical membrane and intracellular recycling pool provided an adequate kinetic description of the I(SC) responses to repetitive stimulation. The model supports the concept of ENaC recycling in response to repetitive cAMP stimulation.
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PMID:Acute ENaC stimulation by cAMP in a kidney cell line is mediated by exocytic insertion from a recycling channel pool. 1562 97

We treated 6 patients with renal collecting duct carcinoma (CDC) in our hospital from December 2004 to December 2011. We compared clinico-pathological findings among all patients. The median age was 58 years (range, 37-77 years). Hematuria, back pain, and fatigue were observed in 5 patients with CDC. Five patients were pathologically diagnosed by radical nephrectomy while a patient was diagnosed by percutaneous renal biopsy without radical nephrectomy. Lymph node metastasis and distant metastasis were observed at diagnosis in 3 and 2 patients, respectively. Five of the 6 patients received systemic therapy after surgery, cytokine therapy in 2 patients, systemic chemotherapy in a patient, and molecular-targeting therapy in 2 patients, respectively. The median overall survival was 15 months (range, 1-44 months). Overall, the 1- and 3-year survival rates were 67 and 33%, respectively. Most of the patients had symptomatic advanced disease at diagnosis. Even though nephrectomy was performed, systemic treatment was not effective in such patients.
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PMID:[Six cases of renal collecting duct carcinoma]. 2529 95

Pseudohypoaldosteronism (PHA) type II is an extremely rare disorder which presents with hypertension, hyperkalemia, and normal anion gap metabolic acidosis. PHA II is also known as familial hyperkalemic hypertension, Gordon syndrome, and chloride shunt syndrome. PHA II is an autosomal dominant disorder and is caused by mutation in WNK1, WNK4, CULLIN3, KLHL3, OSR, SPAK gene. The expression of these proteins is limited to the distal convoluted tube and collecting duct of the kidney. PHA II usually responds to salt restriction and thiazide diuretics. We are reporting here a case of 16-year girl who presented with generalised fatigue and shortness of breath, and blood pressure (BP) of 220/110 mmHg. Laboratory investigation showed hyperkalemia, normal anion gap metabolic acidosis, and hypercalciuria. Workup for secondary causes of hypertension was negative. She responded to thiazide diuretics and her BP is well controlled, and acidosis and hyperkalemia are corrected.
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PMID:Pseudohypoaldosteronism Type II: A Young Girl Presented with Hypertension, Hyperkalemia and Metabolic Acidosis. 2948 94