... the osmoregulatory mechanisms that enable them to maintain internal homeostasis in hypoosmotic environments. In the present study, we focused on the kidney because this is the only organ that can excrete excess water from the body in a hypoosmotic environment. We conducted a transfer experiment of bull sharks from...

.... The kidney appeared to play only a minor role in the elevation of plasma [HCO 3 − ] when M. albus was submerged. However, hypercapnia did lead to an elevation in renal excretion of ammonia, but the attendant rise in the total CO 2 concentration meant that total titratable acid of the urine and hence...

...Patricia A. Wright; Chris M. Wood; Jonathan M. Wilson Increased renal ammonia excretion in response to metabolic acidosis is thought to be a conserved response in vertebrates. We tested the hypothesis that Rhesus (Rh) glycoproteins in the kidney of the freshwater common carp, Cyprinus carpio , play...

...– concentrations between plasma and environment was taken into account (freshwater eels, 6.2 vs 0.3 mmol l –1 ; seawater eels, 0.7 vs 30 mmol l –1 ). One hour after injection of 35 SO 4 2– into the blood of seawater eels, the kidney excreted ∼97% of the ionized form, whereas the radioactivity increased gradually...

...Leslie S. Babonis; Stephanie N. Miller; David H. Evans SUMMARY To understand renal responses to salinity change in aquatic reptiles, we examined the structure and function of the kidney in three species of snake: a marine species with a salt gland ( Laticauda semifasciata ), a marine species...

... linearly from 6 h after SW transfer; however, this did not immediately translate to increased SO 4 2– excretion because the volume of urine was decreased. We identified five SO 4 2– transporters in the eel kidney. Three of these ( Slc26a1, Slc26a6b and Slc26a6c ) are expressed in both SW- and FW-acclimated...

...C. K. Tipsmark; K. J. Sørensen; S. S. Madsen SUMMARY Osmotic balance in fish is maintained through the coordinated regulation of water and ion transport performed by epithelia in intestine, kidney and gill. In the current study, six aquaporin (AQP) isoforms found in Atlantic salmon ( Salmo salar...

... between regional blood flow and tissue oxygen tension. The abundance of transport proteins was determined by immunoblotting. In the obstructed kidney, AUUO caused a prompt decrease in medullary tissue P O 2 to 60% of baseline level whereas cortical tissue P O 2 was unchanged. By contrast, tissue P O 2...

..., and only the former has thus far been cloned in fish. We successfully cloned the V1a-type and V2-type AVT receptor from the kidney of the African lungfish, Protopterus annectens , and the deduced amino acid sequences exhibited high homology with amphibian V1a- and V2-type receptors, respectively...

... of metabolic compensation, with the kidney playing a supporting role. At the gill, cytosolic CA catalyses the hydration of CO 2 to H + and HCO 3 – for export to the water. In the kidney, cytosolic and membrane-bound CA isoforms have been implicated in HCO 3 – reabsorption and urine acidification...

...Shree Ram Singh; Steven X. Hou SUMMARY Excretion is an essential process of an organism's removal of the waste products of metabolism to maintain a constant chemical composition of the body fluids despite changes in the external environment. Excretion is performed by the kidneys in vertebrates...

...Minoru Uchiyama; Ryosuke Kikuchi; Norifumi Konno; Tatsuya Wakasugi; Kouhei Matsuda SUMMARY Urea is the major excretory end product of nitrogen metabolism in most chelonian reptiles. In the present study, we report the isolation of a 1632 base pair cDNA from turtle kidney with one open reading frame...

.... In the goldfish intestine,occludin immunolocalized in a TJ-specific distribution pattern to apical regions of columnar epithelial cells lining the intestinal lumen. In the goldfish kidney, occludin was differentially expressed in discrete regions of the nephron. Occludin immunostaining was strongest in the distal...

...Ray C. Bartolo; John A. Donald SUMMARY In desert rodents, the production of concentrated urine is essential for survival in xeric environments in order to conserve water. Reabsorption of water in the kidney is dependent on large osmotic gradients in the renal medulla. This causes the renal cells...

...Edwin J. W. Geven; Nha-Khanh Nguyen; Marcel van den Boogaart; F. A. Tom Spanings; Gert Flik; Peter H. M. Klaren SUMMARY In teleosts, the thyroid gland is mostly found in the subpharyngeal region. However, in several species thyroid follicles are found in, for example,heart, head kidney and kidney...

... Limited 2007 2007 acid–base balance ventilation lung gill kidney acidosis alkalosis African lungfish Protopterus annectens The regulation of metabolic acid–base disturbances can occur through the control of ventilation and/or the direct transfer of acid–base equivalents between...

... and distribution of the urea transporter (UT) in the kidney of the marine toad( Bufo marinus ), and its expression in the kidney and urinary bladder following exposure to dry and hyper-saline conditions by means of cDNA cloning, semi-quantitative RT-PCR, immunoblot analysis and immunohistochemistry. The Bufo UT...

... and kidneys. Two different responses were recorded after a long-term freshwater acclimatization. (1) Successfully adapted sea-bass displayed standard behavior; their blood osmolality was maintained almost constant after the freshwater challenge, attesting to their efficient hyperosmoregulation...

... + -ATPase ion flux kidney evolution The common killifish, Fundulus heteroclitus , inhabits brackish water estuaries and salt marshes along the eastern coast of North America. The species distribution is latitudinal, from Newfoundland to Florida, and thus spans a cline of environmental...

... often deal with exceptionally high water intake rates in order to meet their high mass-specific energy demands. Birds that ingest large volumes of water may either eliminate excess water in the kidney or regulate the volume of water absorbed in the gastrointestinal tract. Because water absorption...