Collecting Tubules (collecting + tubule)

Distribution by Scientific Domains


Selected Abstracts


Renal pathology of polycystic kidney disease and concurrent hereditary nephritis in Bull Terriers

AUSTRALIAN VETERINARY JOURNAL, Issue 6 2002
CA O'LEARY
Objective To describe the renal lesions in Bull Terrier poly-cystic kidney disease (BTPKD), to confirm that the renal cysts in BTPKD arise from the nephron or collecting tubule, and to identify lesions consistent with concurrent BTPKD and Bull Terrier hereditary nephritis (BTHN). Design Renal tissue from five Bull Terriers with BTPKD and eight control dogs was examined by light and transmission electron microscopy. Clinical data were collected from all dogs, and family history of BTPKD and BTHN for all Bull Terriers. Results In BTPKD the renal cysts were lined by epithelial cells of nephron or collecting duct origin that were usually squamous or cuboidal, with few organelles. They had normal junctional complexes, and basal laminae of varying thicknesses. Glomeruli with small, atrophic tufts and dilated Bowman's capsules, tubular loss and dilation, and interstitial inflammation and fibrosis were common. Whereas the lesions seen in BTHN by light microscope were nonspecific, the presence of characteristic ultrastructural glomerular basement membrane (GMB) lesions and a family history of this disease indicated concurrent BTHN was likely in three of five cases of BTPKD. Conclusion This paper provides evidence that renal cysts in BTPKD are of nephron or collecting duct origin. In addition, GBM lesions are described that strongly suggest that BTPKD and BTHN may occur simultaneously. [source]


Real time monitoring of BMP Smads transcriptional activity during mouse development

GENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 7 2008
Rui M. Monteiro
Sagittal section of a 5-day-old mouse kidney expressing a bone morphogenetic protein-response element:green fluorescent protein (BRE:gfp) transgene. GFP expression detected by immunofluorescence (green) reveals BMP Smad transcriptional activity in the glumeruli and adjacent collecting tubules. See the paper by Monteiro et al., in this issue. (Image provided by Monika Bialecka). [source]


Aquaporin-1 and aquaporin-2 urinary excretion in cirrhosis: Relationship with ascites and hepatorenal syndrome,

HEPATOLOGY, Issue 6 2006
Christina Esteva-Font
Several experimental models of cirrhosis have shown dysregulation of renal aquaporins in different phases of liver disease. We investigated the urinary excretion of both aquaporin-1 and aquaporin-2 in patients with cirrhosis at different stages of the disease. Twenty-four-hour urine was collected from 11 healthy volunteers, 13 patients with compensated cirrhosis (without ascites), and 20 patients with decompensated cirrhosis (11 with ascites without renal failure and 9 with hepatorenal syndrome). Aquaporin-1 and aquaporin-2 excretion was analyzed by immunoblotting. Urinary aquaporin-2 excretion was reduced in patients with cirrhosis compared to healthy subjects. A progressive decrease in urinary aquaporin-2 excretion was observed as the severity of cirrhosis increased, from compensated cirrhosis to cirrhosis with ascites and hepatorenal syndrome. Patients with hyponatremia had lower urinary aquaporin-2 excretion than patients without hyponatremia. Vasopressin plasma level did not correlate with aquaporin-2 excretion. There were no differences between healthy subjects and patients with cirrhosis with or without ascites in urinary excretion of aquaporin-1, but urinary aquaporin-1 excretion of those with hepatorenal syndrome was extremely low. In conclusion, patients with cirrhosis appear to exhibit a decreased abundance of renal aquaporin-2 and therefore lower water permeability in the collecting tubules. This may represent an adaptive renal response to sodium retention, with expansion of extracellular fluid volume and dilutional hyponatremia observed in those who have cirrhosis with ascites. Finally, aquaporin-1 does not appear to play a role in the progressive dysregulation of extracellular fluid volume in cirrhosis. (HEPATOLOGY 2006;44:1555,1563.) [source]


Polycystins: what polycystic kidney disease tells us about sperm

MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 4 2004
Abraham L. Kierszenbaum
Abstract Experimental evidence indicates that the membrane-associated proteins polycystin-1 and polycystin-2 operate as a receptor-calcium channel complex that regulates signaling pathways essential for modulation of renal tubulogenesis. Polycystic kidney disease is characterized by defective renal tubular structure and results from mutations in either PKD1 or PKD2 genes. Recent data suggest that polycystin-1 and polycystin-2 might localize to primary cilium in principal cells of renal collecting tubules and are thought to act as mechanosensors of fluid flow and contents. Ciliary bending by fluid flow or mechanical stimulation induce Ca2+ release from intracellular stores, presumably to modulate ion influx in response to tubular fluid flow. Polycystins are also emerging as playing a significant role in sperm development and function. Drosophila polycystin-2 is associated with the head and tail of mature sperm. Targeted disruption of the PKD2 homolog results in nearly complete male sterility without disrupting spermatogenesis. Mutant sperm are motile but are unable to reach the female storage organs (seminal receptacles and spermathecae). The sea urchin polycystin-1-equivalent suPC2 colocalizes with the polycystin-1 homolog REJ3 to the plasma membrane over the acrosomal vesicle. This localization site suggests that the suPC2-REJ3 complex may function as a cation channel mediating acrosome reaction when sperm contact the jelly layer surrounding the egg at fertilization. Future studies leading to the identification of specific ligands for polycystins, including the signaling pathways, might define the puzzling relationship between renal tubular morphogenesis and sperm development and function. Mol. Reprod. Dev. 67: 385,388, 2004. © 2004 Wiley-Liss, Inc. [source]


Development of the Mesonephros in Camel (Camelus dromedarius)

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2007
K. H. Aly
Summary The study of the development of the mesonephros in the camel (Camelus dromedarius) was carried out on 16 embryos ranging from 0.9 to 8.6 cm crown vertebral rump length (CVRL). At 0.9 cm CVRL, the mesonephros is represented by a narrow strip along the roof of the thoracolumbar part of the vertebral column. At 1.4 cm CVRL, some of the mesonephric tubules are canalized but others are still solid. The mesonephric corpuscles are well developed at 1.9 cm CVRL and occupy almost the entire abdominal cavity in between the liver and the gut. Histologically, the glomeruli occupy the ventromedial aspect of the mesonephros while the mesonephric tubules become numerous, larger and more coiled. At 3 cm CVRL, the metanephros is invaginated in the caudal pole of the mesonephros, and the mesonephric tubules in some areas are differentiated into secretory and collecting tubules. At 3.5 cm CVRL the mesonephros is related dorsally to the postcardinal vein and ventrally to the subcardinal vein. At 4.7 cm CVRL continuous regression of the mesonephros from cranialwards to caudalwards is observed. At 5.3,5.5 cm CVRL, the cranial part of the mesonephros is divided into medial and lateral regions, and later the medial region completely disappears and is replaced by the primordium of the adrenal gland. At 8.6 cm CVRL, the caudal part of the mesonephros completely disappears. [source]


The Development of the Metanephric Kidney in the Pig

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005
H. Bragulla
Aims:, The metanephric kidneys of the pig are used as xenotransplants in human medicine. In order for transplants to fit within the host organisms, the subcapsular blastema and blood vessels are crucial for the development of new nephrons to sustain the organ functions. The aim of this study is to obtain data concerning the post-natal development of metanephric nephrons in the porcine kidney. Materials and Methods:, The metanephric kidneys of six porcine fetuses with a crown-rump length ranging from 40 mm to 220 mm of eight piglets aged between 6 to 10 weeks and of three adult pigs were studied. Eight lectins as well as anti-actin and anti-myosin antibodies were used for lectin- and immunohistochemistry to study the subcapsular metanephric blastema, to visualize the blood-urine barrier in the nephrons and collecting tubules, and to study the blood vessels in both the renal cortex and marrow. Results and Conclusions:, A subcapsular metanephric blastema was still present in the kidney of 10-week-old piglets. Dense condensation of mesenchymal cells surrounded the terminal branches of the collecting ducts and showed first signs of mesenchymal-epithelial transformation. Characteristic comma-shaped and s-shaped bodies were found in and underneath the subcapsular blastema. In the fibrous renal capsule of six-week-old piglets, a first faint binding reaction of anti-actin was visible and intensified in the fibrous renal capsule in ten-week-old piglets and in adult pigs. In addition, the smooth-muscle layers of the blood vessels were stained by the anti-actin and anti-myosin antibodies. The lectins showed various affinities to the endothelium of blood vessels and to the epithelial cells lining of the capsules of the metanephric renal corpuscles, the various parts of the renal tubules, as well as the collecting tubules and the renal pelvis. The affinity of the epithelial cells to a specific lectin varies in neighbouring cells, indicating different cell activities or cell cycles. [source]


Immunolocalization of Na+, K+ -ATPase-rich cells in the gill and urinary system of Persian sturgeon, Acipenser persicus, fry

AQUACULTURE RESEARCH, Issue 3 2009
Saber Khodabandeh
Abstract Localization of Na+, K+ -ATPase-rich cells in the gill and urinary system of Acipenser persicus fry was performed through immunofluorescence light microscopy using a mouse monoclonal antibody IgG,5 raised against the ,-subunit of chicken Na+, K+ -ATPase. Different types of epithelia were clearly identified in the gill epithelium: epithelia of branchial arch, interbranchial septum, filament and lamellar epithelium. The Na+, K+ -ATPase-rich cells were found in the epithelia of branchial arch, interbranchial septum, filament, interlamellar region and also in the lamellae. Histologically, the urinary system is divided into head kidney, trunk kidney and short caudal kidney. The head kidney is composed of the pronephric tubules and the haemopoietic tissues, while the trunk kidney is composed of a large number of glomeruli and convoluted nephrons. Each nephron consisted of a large glomerulus and tubules (neck, proximal, distal and collecting tubules) which connected to ureters. Posteriorly, ureters extended and joined together to form a small urinary bladder. In the urinary system, no specific fluorescence staining was observed in the glomerulus, neck segment and proximal tubules. The distal tubule cells and collecting tubule cells showed a strong immunostaining of Na+, K+ -ATPase. Epithelia of ureters and urinary bladder also showed several isolated immunofluorescent cells. Immunofluorescent cells were rich in Na+, K+ -ATPase enzyme which is very important for osmoregulation. [source]