...Amit Kumar Sinha; Hon Jung Liew; C. Michele Nawata; Ronny Blust; Chris M. Wood; Gudrun De Boeck SUMMARY We investigated relationships among branchial unidirectional Na + fluxes, ammonia excretion, urea excretion, plasma ammonia, plasma cortisol, and gill transporter expression and function in three...

... of the kidney during immersion. When restrained on land, P. sinensis occasionally submerged their head into water (20–100 min), during which urea excretion and oxygen extraction occurred simultaneously. These results indicate for the first time that buccopharyngeal villiform processes (BVP) and rhythmic...

... ) 12 3 2009 © The Company of Biologists Limited 2009 2009 toadfish urea excretion cortisol glucocorticoid receptor mineralocorticoid receptor metyrapone RU-486 spironolactone aldosterone The gulf toadfish, Opsanus beta , is one of several unusual teleosts that have...

... glutamine, and the toadfish urea transporter, tUT, which is involved in urea excretion across the gill of the gulf toadfish. GS (of which there are two isoforms, LGS and GGS) and tUT mRNA expression and activity were measured in toadfish exposed to treatments that would induce variable stress responses...

... for a functional OUC. Embryos (4 and 8 months) survived and recovered from exposure to 5 days of 75% SW. There was a significant increase in the rate of urea excretion (five- to tenfold), no change in OUC enzyme activities, and significant decreases in the tissue content of urea, TMAO and other osmolytes...

... in a layer of dried mucus in open air in the laboratory. Despite decreases in rates of ammonia and urea excretion, the ammonia content in the muscle, liver, brain and gut of P. dolloi remained unchanged after 6 days of aestivation compared with the control fasted for 6 days. For specimens aestivated for 40...

... or urea excretion). References Anderson, P. M. ( 1980 ). Glutamine- and N-acetylglutamate-dependent carbamoyl phosphate synthetase in elasmobranchs. Science 208 , 291 -293. Anderson, P. M. ( 1991 ). Glutamine-dependent urea synthesis in elasmobranch fishes. Biochem. Cell Biol. 69 , 317...

...] reversibly inhibited urea excretion from the embryos to the external water. Unidirectional urea influx was inhibited by acetamide and thiourea, with IC 50 values of 0.04 and 0.05 mmol l −1 , respectively. Influx of urea from the external water to the embryo tended to saturate at elevated external urea...

... to neutral water (pH7, total CO 2 <1mmol l −1 ) results in a complete inhibition of urea excretion. In the present study, we further characterized the physiological effects of transferring O. a. grahami from alkaline to neutral water. Exposure to neutral water resulted in a significant decrease in blood...