Exposure to brackish water, upon feeding, leads to enhanced conservation of nitrogen and increased urea synthesis and retention in the Asian freshwater stingray Himantura signifer
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منابع مشابه
Exposure to brackish water, upon feeding, leads to enhanced conservation of nitrogen and increased urea synthesis and retention in the Asian freshwater stingray Himantura signifer.
The white-edge freshwater whip ray Himantura signifer is ammonotelic in freshwater, but retains the capacities of urea synthesis and ureosmotic osmoregulation to survive in brackish water. The first objective of this study was to examine whether exposure to brackish water would lead to increases in food intake, and/or conservation of nitrogen in H. signifer upon daily feeding. Results obtained ...
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L-gulono-γ-lactone oxidase (Gulo) catalyzes the last step of ascorbic acid biosynthesis, which occurs in the kidney of elasmobranchs. This study aimed to clone and sequence gulonolactone oxidase (gulo) from the kidney of the euryhaline freshwater stingray, Himantura signifer, and to determine the effects of acclimation from freshwater to brackish water (salinity 20) on its renal gulo mRNA expre...
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The white-edge freshwater whip ray Himantura signifer can survive in freshwater (0.7 per thousand ) indefinitely or in brackish water (20 per thousand ) for at least two weeks in the laboratory. In freshwater, the blood plasma was maintained hyperosmotic to that of the external medium. There was approximately 44 mmol l(-1) of urea in the plasma, with the rest of the osmolality made up mainly by...
متن کاملBranchial Na+:K+:2Cl− cotransporter 1 and Na+/K+-ATPase α-subunit in a brackish water-type ionocyte of the euryhaline freshwater white-rimmed stingray, Himantura signifer
Himantura signifer is a freshwater stingray which inhabits rivers in Southeast Asia. It can survive in brackish water but not seawater. In brackish water, it becomes partially ureosmotic, but how it maintains its plasma hypoionic to the external medium is enigmatic because of the lack of a rectal gland. Here, we report for the first time the expression of Na(+):K(+):2Cl(-) cotransporter 1 (nkcc...
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ژورنال
عنوان ژورنال: Journal of Experimental Biology
سال: 2006
ISSN: 1477-9145,0022-0949
DOI: 10.1242/jeb.02002