Abstract
The osmorespiratory compromise, the trade-off between the requirements for respiratory and ionoregulatory homeostasis at the gills, becomes more intense during environmental hypoxia. One aspect that has been previously overlooked is possible change in transepithelial potential (TEP) caused by hypoxia, which will influence branchial ionic fluxes. Using the euryhaline killifish, we show that acute hypoxia reduces the TEP across the gills by approximately 10 mV in animals acclimated to both freshwater (FW) and seawater (SW), with a higher PO2 threshold in the former. TEP becomes negative in FW, and less positive in SW. The effects are immediate, stable for at least 3 h, and reverse immediately upon return to normoxia. Hypoxia also blocks the normal increase in TEP that occurs upon transfer from FW to SW, but does not reduce the fall in TEP that occurs with transfer in the opposite direction. These effects may be beneficial in FW but not in SW.
Original language | English (US) |
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Pages (from-to) | 2152-2155 |
Number of pages | 4 |
Journal | Journal of Experimental Biology |
Volume | 218 |
Issue number | 14 |
DOIs | |
State | Published - Jul 1 2015 |
Keywords
- Diffusion potential
- Electrogenic potential
- Gill permeability
- P/P ratio
- Transepithelial potential
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Physiology
- Aquatic Science
- Animal Science and Zoology
- Molecular Biology
- Insect Science