Physicochemical properties of the dissolved organic carbon can lead to different physiological responses of zebrafish (Danio rerio) under neutral and acidic conditions. Issue 9 (26th August 2021)

• Record Type: Journal Article
• Authors: Sadauskas‐Henrique, Helen; Smith, D. Scott; Val, Adalberto L.; Wood, Chris M.
• Other Names: Pelster Bernd guestEditor.; Val Adalberto L. guestEditor.
• Is Part Of: Journal of experimental zoology. Volume 335:Issue 9/10(2021)
• Page Start: 864
• Page End: 878
• Publication Date: 2021-08-26
• Subjects: Na+K+ATPase -- osmoregulation -- PARAFAC analysis -- SAC340 -- spectroscopic features -- v‐type H+ATPase; Zoology -- Periodicals; Zoology; Animal Population Groups -- physiology; Zoology; Electronic journals; Periodical; Periodicals; 590
• DOI: 10.1002/jez.2537
• Languages: English
• ISSNs: 2471-5646

Abstract

Abstract: Previous studies have suggested that the capacity of natural dissolved organic carbon (DOC) molecules to interact with biological membranes is associated with their aromaticity (SAC340 ); origin (allochthonous versus autochthonous, FI); molecular weight (Abs254/365 ); and relative fluorescence of DOC moieties (PARAFAC analysis). These interactions may be especially important when fish are challenged by acidic waters, which are known to inhibit the active uptake of Na + and Cl ‐, while stimulating diffusive ion losses in freshwater fishes. Therefore, zebrafish were acclimated (7 days, pH 7.0) to five natural DOC sources (10 mg C/L), two from the Amazon Basin and three from Canada, together with a "no‐added DOC" control. After the acclimation, fish were challenged by exposure to acidic water (pH 4.0) for 3 h. Osmoregulatory parameters were measured at pH 7.0 and 4.0. Acclimation to the five DOC sources did not disturb Na +, Cl ‐ and ammonia net fluxes, but resulted in differential elevations in Na +, K + ATPase and v‐type H + ATPase activities in fish at pH 7.0. However, after transfer to pH.4.0, the control fish exhibited rapid increases in both enzymes. In contrast the DOC‐ acclimated animals exhibited unchanged (Na +, K + ATPase) or differentially increased (v‐type H + ATPase) activities. Na +, Cl ‐ and ammonia net fluxes remained unchanged in the control fish, but were differentially elevated in most of the DOC treatments at pH 4.0, relative to the same DOC treatments at pH 7.0. Correlations between the osmoregulatory data the DOCs properties highlight that the DOC properties drive different effects on gill physiology. Abstract : The graphical abstract caption:Main physiological responses of zebrafish (Danio rerio) when acclimated (7 days, pH 7.0) to five natural dissolved organic carbon (DOC) sources (10 mg C/L), two from the Amazon Basin (upper Rio Negro at São Gabriel da Cachoeira (SGC) and Solimões river (SOL)) and three from Canada (maple tree leaf‐derived DOC (MP), Luther Marsh (LM) and Bannister lake (BL)), and after challenge by exposure to acidic water (pH 4.0) for 3 h. Research Highlights: 1. Gill ionoregulatory enzyme activities were differentially elevated by DOC at pH 7.0. 2. All DOC treatments at pH 4.0 led to increases in Na +, Cl ‐ and ammonia net fluxes. 3. Differences in DOC properies differentially altered gill function in zebrafish.