|Reference : Absence of tiGh effect on adaptability to brackish water in Tilapia (Oreochromis nilotic...|
|Scientific journals : Article|
|Life sciences : Anatomy (cytology, histology, embryology...) & physiology|
|Absence of tiGh effect on adaptability to brackish water in Tilapia (Oreochromis niloticus)|
|Auperin, B. [Institut Scientifique de Recherche Agronomique - INRA > > Physiologie des Poissons > >]|
|Leguen, I. [Institut Scientifique de Recherche Agronomique - INRA > > Physiologie des Poissons > >]|
|Rentier-Delrue, Françoise [Université de Liège - ULg > > Biologie et génétique moléculaire > >]|
|Smal, J. [Eurogentec > > > >]|
|Prunet, P. [Institut Scientifique de Recherche Agronomique - INRA > > Physiologie des Poissons > >]|
|General and Comparative Endocrinology|
|[en] Tilapia ; growth-hormone ; adaptability to brackish water|
|[en] The aim of this study was to investigate the possible role of growth hormone in the adaptation of tilapia (Oreochromis niloticus) to brackish water and to analyze its interactions with prolactin in this process. Plasma levels of growth hormone do not change upon transfer to brackish water. Treatment of intact tilapia in fresh water with growth hormone prior to transfer did not enable the fish to preadapt to brackish water: the duration of the hydromineral imbalance after transfer was the same in treated animals and controls. The major osmoregulatory role of prolactin in fresh water led us to test the hypothesis that prolactin might antagonize the effect of growth hormone on adaptation to brackish water. Growth-hormone-treated hypophysectomized animals, however, exhibited no increased osmoregulatory capacity as compared to hypophysectomized controls, confirming the absence of a growth-hormone-related osmoregulatory effect. When prolactin and growth hormone were coinjected, growth hormone also proved unable to oppose the Na+ retaining effect of prolactin, in both brackish and fresh water. Surprisingly, hypophysectomized animals adapt better to brackish water than do sham-operated animals. This result is discussed in light of the effects of prolactin and cortisol on osmoregulation in brackish water and we suggest that an important event which allows O. niloticus to adapt to hyperosmotic environment is the reduction of plasma PRL upon transfer to brackish water.|
There is no file associated with this reference.
All documents in ORBi are protected by a user license.