TY - JOUR
T1 - Osmoregulation and epithelial water transport
T2 - Lessons from the intestine of marine teleost fish
AU - Whittamore, Jonathan M.
N1 - Funding Information:
Acknowledgments I wish to extend my gratitude to Prof. Ian Hume for the invitation to write this article, and my sincerest thanks to Drs Chris Cooper and Erin Reardon for taking the time to read and offer comments on an earlier draft of this manuscript. I would also like to acknowledge the assistance of Laura Simington for helping to produce Fig. 2. This work was supported by grant BB/F009364/1 from the Biotechnology and Biological Sciences Research Council (BBSRC).
PY - 2012/1
Y1 - 2012/1
N2 - For teleost fish living in seawater, drinking the surrounding medium is necessary to avoid dehydration. This is a key component of their osmoregulatory strategy presenting the challenge of excreting excess salts while achieving a net retention of water. The intestine has an established role in osmoregulation, and its ability to effectively absorb fluid is crucial to compensating for water losses to the hyperosmotic environment. Despite this, the potential for the teleost intestine to serve as a comparative model for detailed, integrative experimental studies on epithelial water transport has so far gone largely untapped. The following review aims to present an assessment of the teleost intestine as a fluid-transporting epithelium. Beginning with a brief overview of marine teleost osmoregulation, emphasis shifts to the processing of ingested seawater by the gastrointestinal tract and the characteristics of intestinal ion and fluid transport. Particular attention is given to acid-base transfers by the intestine, specifically bicarbonate secretion, which creates the distinctly alkaline gut fluids responsible for the formation of solid calcium carbonate precipitates. The respective contributions of these unique features to intestinal fluid absorption, alongside other recognised ion transport processes, are then subsequently considered within the wider context of the classic physiological problem of epithelial water transport.
AB - For teleost fish living in seawater, drinking the surrounding medium is necessary to avoid dehydration. This is a key component of their osmoregulatory strategy presenting the challenge of excreting excess salts while achieving a net retention of water. The intestine has an established role in osmoregulation, and its ability to effectively absorb fluid is crucial to compensating for water losses to the hyperosmotic environment. Despite this, the potential for the teleost intestine to serve as a comparative model for detailed, integrative experimental studies on epithelial water transport has so far gone largely untapped. The following review aims to present an assessment of the teleost intestine as a fluid-transporting epithelium. Beginning with a brief overview of marine teleost osmoregulation, emphasis shifts to the processing of ingested seawater by the gastrointestinal tract and the characteristics of intestinal ion and fluid transport. Particular attention is given to acid-base transfers by the intestine, specifically bicarbonate secretion, which creates the distinctly alkaline gut fluids responsible for the formation of solid calcium carbonate precipitates. The respective contributions of these unique features to intestinal fluid absorption, alongside other recognised ion transport processes, are then subsequently considered within the wider context of the classic physiological problem of epithelial water transport.
KW - Aquaporins
KW - Lateral intercellular space
KW - Solute-linked water transport
KW - Tight junction
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U2 - 10.1007/s00360-011-0601-3
DO - 10.1007/s00360-011-0601-3
M3 - Review article
C2 - 21735220
AN - SCOPUS:84855294935
SN - 0174-1578
VL - 182
SP - 1
EP - 39
JO - Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology
JF - Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology
IS - 1
ER -