TY - JOUR
T1 - Fundulus heteroclitus acutely transferred from seawater to high salinity require few adjustments to intestinal transport associated with osmoregulation
AU - Genz, Janet
AU - Grosell, Martin
N1 - Funding Information:
This work was supported by NSF grant IAB0743903 to M. Grosell.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2011/10
Y1 - 2011/10
N2 - The common killifish, Fundulus heteroclitus, has historically been a favorite organism for the study of euryhalinity in teleost fish. Despite the species' large range of salinity tolerance, studies of osmoregulation in high salinity are rare, with most previous studies focused on fish transferred between freshwater and seawater. Similarly, while branchial transport properties have been studied extensively, there are relatively few studies investigating the role of the intestine in osmoregulation in killifish. This study sought to characterize the fluid and ion transport occurring in the intestinal tract of killifish adapted to seawater, and furthermore to investigate the adjustments that occur to these mechanisms following acute transfer to high salinity (70ppt). In vivo samples of blood plasma and intestinal fluids of seawater-acclimated killifish indicated absorption of Na +, Cl -, and water, the relative impermeability of the intestine to Mg 2+ and SO 4 2-, and active secretion of HCO 3 - into the intestinal lumen. The details of these processes were investigated further using in vitro techniques of isolated intestinal sac preparations and an Ussing chamber pH-stat titration system. However, these methods were discovered to be of limited utility under physiologically relevant conditions due to tissue deterioration. Results that could be validly interpreted suggested that there are few changes to intestinal transport following transfer to high salinity, and that adjustments to epithelial permeability occur in the first 24h post-transfer.
AB - The common killifish, Fundulus heteroclitus, has historically been a favorite organism for the study of euryhalinity in teleost fish. Despite the species' large range of salinity tolerance, studies of osmoregulation in high salinity are rare, with most previous studies focused on fish transferred between freshwater and seawater. Similarly, while branchial transport properties have been studied extensively, there are relatively few studies investigating the role of the intestine in osmoregulation in killifish. This study sought to characterize the fluid and ion transport occurring in the intestinal tract of killifish adapted to seawater, and furthermore to investigate the adjustments that occur to these mechanisms following acute transfer to high salinity (70ppt). In vivo samples of blood plasma and intestinal fluids of seawater-acclimated killifish indicated absorption of Na +, Cl -, and water, the relative impermeability of the intestine to Mg 2+ and SO 4 2-, and active secretion of HCO 3 - into the intestinal lumen. The details of these processes were investigated further using in vitro techniques of isolated intestinal sac preparations and an Ussing chamber pH-stat titration system. However, these methods were discovered to be of limited utility under physiologically relevant conditions due to tissue deterioration. Results that could be validly interpreted suggested that there are few changes to intestinal transport following transfer to high salinity, and that adjustments to epithelial permeability occur in the first 24h post-transfer.
KW - Electrophysiology
KW - Gut sac
KW - Killifish
KW - Ussing chamber
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U2 - 10.1016/j.cbpa.2011.05.027
DO - 10.1016/j.cbpa.2011.05.027
M3 - Article
C2 - 21664478
AN - SCOPUS:79960699085
VL - 160
SP - 156
EP - 165
JO - Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology
JF - Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology
SN - 1095-6433
IS - 2
ER -