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Endocrine control of osmoregulation in teleost fish

January 1, 2001

SYNOPSIS. As the primary link between environmental change and physiological response, the neuroendocrinesystem is a critical part of osmoregulatory adaptations. Cortisol has been viewpd as 'the' seawater-adapting hormone in fish and prolactin as 'the' fresh water adapting hormone. Recent evidence indicates that the growth hormone/insulin-like growth factor I axis is also important in seawater adaptation in several teleosts of widely differing evolutionary lineages. In salmonids, growth hormone acts in synergy with cortisol to increase seawater tolerance, at least partly through the upregulation of gill cortisol receptors. Cortisol under some conditions may promote ion uptake and interacts with prolactin during acclimation to fresh water. The osmoregulatory actions of growth hormone and prolactin are antagonistic. In some species, thyroid hormones support the action of growth hormone and cortisol in promoting seawater acclimation. Although a broad generalization that holds for all teleosts is unlikely, our current understanding indicates that growth hormone promotes acclimation to seawater, prolactin promotes acclimation to fresh water, and cortisol interacts with both of these hormones thus having a dual osmoregulatory function.

Publication Year 2001
Title Endocrine control of osmoregulation in teleost fish
Authors S. D. McCormick
Publication Type Article
Publication Subtype Journal Article
Series Title American Zoologist
Index ID 70023490
Record Source USGS Publications Warehouse