Please use this identifier to cite or link to this item:
|Title:||Enzymatic and mitochondrial responses to 5 months of aerial exposure in the slender lungfish Protopterus dolloi|
|Citation:||Staples, J.F., Kajimura, M., Wood, C.M., Patel, M., Ip, Y.K., McClelland, G.B. (2008-08). Enzymatic and mitochondrial responses to 5 months of aerial exposure in the slender lungfish Protopterus dolloi. Journal of Fish Biology 73 (3) : 608-622. ScholarBank@NUS Repository. https://doi.org/10.1111/j.1095-8649.2008.01955.x|
|Abstract:||Mitochondrial respiration and activities of key metabolic enzymes from liver and white skeletal muscle were compared between control aquatic slender lungfish Protopterus dolloi, and those exposed to air for 5 months. Activities of citrate synthase, glycogen phosphorylase, phosphofructokinase and pyruvate kinase in liver were not affected by air-exposure. In muscle, air-exposure reduced citrate synthase and pyruvate kinase activities (relative to tissue wet mass) by 63 and 50%, respectively. Liver carnitine palmitoyl transferase activity (relative to mitochondrial protein) decreased by half following air-exposure, but there was no change in muscle. In mitochondria isolated from muscle, state 3 and state 4 respiration were reduced by 74 and 89%, respectively following air-exposure, but liver mitochondria were not affected. In liver, air-exposure increased activities of ornithine-urea cycle enzymes including glutamine synthase, carbamoyl-phosphate synthase III and arginase, by 1.9- to 4.2-fold. Carbamoyl-phosphate synthase III activity could not be detected in muscle, indicating that urea is not synthesized in this tissue. These data suggest that skeletal muscle metabolism is downregulated in air-exposure, conserving energy and protein during a period when the animals cannot forage. In contrast, ATP production capacities in the liver are maintained, and this may permit expensive urea biosynthesis to continue during aerial exposure. © 2008 The Authors.|
|Source Title:||Journal of Fish Biology|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Sep 22, 2018
WEB OF SCIENCETM
checked on Sep 12, 2018
checked on Jul 13, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.