title: Effect of Salinity and Alkalinity onLuciobarbus capitoGill Na+/K+-ATPase Enzyme Activity, Plasma Ion Concentration, and Osmotic Pressure.
abstract: We evaluated the individual and combined effects of salinity and alkalinity on gill Na+/K+-ATPase enzyme activity, plasma ion concentration, and osmotic pressure inLuciobarbus capito. Increasing salinity concentrations (5, 8, 11, and 14 g/L) were associated with an initial increase and then decrease inL. capitogill Na+/K+-ATPase activity. Activity was affected by the difference between internal and external Na+ion concentrations and osmotic pressure (P< 0.05). Both plasma ion (Na+, K+, and Cl-) concentration and osmotic pressure increased significantly (P< 0.05). An increase in alkalinity (15, 30, 45, and 60 mM) caused a significant increase in plasma K+and urea nitrogen concentrations (P< 0.05) but had no effect on either plasma osmotic pressure or gill filament ATPase activity. In the two-factor experiment, the saline-alkaline interaction caused a significant increase in plasma ion (Na+, Cl-, and urea nitrogen) and osmotic pressure (P< 0.05). Variance analysis revealed that salinity, alkalinity, and their interaction significantly affected osmotic pressure, with salinity being most affected, followed by alkalinity, and their interaction. Gill filament ATPase activity increased at first and then decreased; peak values were observed in the orthogonal experiment group at a salinity of 8 g/L and alkalinity of 30 mM.
authors.affiliation: Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China.
authors.forename: Longwu
authors.identifier: 0000-0002-0268-3912
authors.initials: L
authors.lastname: Geng
authors.affiliation: Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China.
authors.forename: Guangxiang
authors.identifier: 0000-0003-1150-5058
authors.initials: G
authors.lastname: Tong
authors.affiliation: Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China.
authors.forename: Haifeng
authors.identifier: 0000-0003-1398-6916
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China.
authors.forename: Wei
authors.identifier: 0000-0002-9874-4184
authors.initials: W
authors.lastname: Xu
mesh_terms: D000468:Alkalies / Q000737:chemistry; D000818:Animals; D003530:Cyprinidae / Q000378:metabolism; D005880:Gills / Q000201:enzymology; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000097:blood*; D009997:Osmotic Pressure; D054712:Salinity; D012964:Sodium / Q000097:blood*; D000254:Sodium-Potassium-Exchanging ATPase / Q000096:biosynthesis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D000468:Alkalies; D007477:Ions; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase