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Pérez-Sánchez J, Simó-Mirabet P, Naya-Català F, Martos-Sitcha JA, Perera E, Bermejo-Nogales A, Benedito-Palos L, Calduch-Giner JA. Somatotropic Axis Regulation Unravels the Differential Effects of Nutritional and Environmental Factors in Growth Performance of Marine Farmed Fishes. Front Endocrinol (Lausanne) 2018; 9:687. [PMID: 30538673 PMCID: PMC6277588 DOI: 10.3389/fendo.2018.00687] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 11/02/2018] [Indexed: 12/23/2022] Open
Abstract
The Gh/Prl/Sl family has evolved differentially through evolution, resulting in varying relationships between the somatotropic axis and growth rates within and across fish species. This is due to a wide range of endogenous and exogenous factors that make this association variable throughout season and life cycle, and the present minireview aims to better define the nutritional and environmental regulation of the endocrine growth cascade over precisely defined groups of fishes, focusing on Mediterranean farmed fishes. As a result, circulating Gh and Igf-i are revitalized as reliable growth markers, with a close association with growth rates of gilthead sea bream juveniles with deficiency signs in both macro- or micro-nutrients. This, together with other regulated responses, promotes the use of Gh and Igf-i as key performance indicators of growth, aerobic scope, and nutritional condition in gilthead sea bream. Moreover, the sirtuin-energy sensors might modulate the growth-promoting action of somatotropic axis. In this scenario, transcripts of igf-i and gh receptors mirror changes in plasma Gh and Igf-i levels, with the ghr-i/ghr-ii expression ratio mostly unaltered over season. However, this ratio is nutritionally regulated, and enriched plant-based diets or diets with specific nutrient deficiencies downregulate hepatic ghr-i, decreasing the ghr-i/ghr-ii ratio. The same trend, due to a ghr-ii increase, is found in skeletal muscle, whereas impaired growth during overwintering is related to increase in the ghr-i/ghr-ii and igf-ii/igf-i ratios in liver and skeletal muscle, respectively. Overall, expression of insulin receptors and igf receptors is less regulated, though the expression quotient is especially high in the liver and muscle of sea bream. Nutritional and environmental regulation of the full Igf binding protein 1-6 repertoire remains to be understood. However, tissue-specific expression profiling highlights an enhanced and nutritionally regulated expression of the igfbp-1/-2/-4 clade in liver, whereas the igfbp-3/-5/-6 clade is overexpressed and regulated in skeletal muscle. The somatotropic axis is, therefore, highly informative of a wide-range of growth-disturbing and stressful stimuli, and multivariate analysis supports its use as a reliable toolset for the assessment of growth potentiality and nutrient deficiencies and requirements, especially in combination with selected panels of other nutritionally regulated metabolic biomarkers.
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Li M, Jiang C, Zhang Y, Zhang S. Activities of Amphioxus GH-Like Protein in Osmoregulation: Insight into Origin of Vertebrate GH Family. Int J Endocrinol 2017; 2017:9538685. [PMID: 28408927 PMCID: PMC5376476 DOI: 10.1155/2017/9538685] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 11/14/2016] [Indexed: 01/21/2023] Open
Abstract
GH is known to play an important role in both growth promotion and osmoregulation in vertebrates. We have shown that amphioxus possesses a single GH-like hormone (GHl) gene encoding a functional protein capable of promoting growth. However, if GHl can mediate osmoregulation remains open. Here, we demonstrated clearly that GHl increased not only the survival rate of amphioxus but also the muscle moisture under high salinity. Moreover, GHl induced the expression of both the ion transporter Na+-K+-ATPase (NKA) and Na+-K+-2Cl- cotransporter (NKCC) in the gill as well as the mediator of GH action IGFl in the hepatic caecum, indicating that GHl fulfills this osmoregulatory activity through the same mechanisms of vertebrate GH. These results together suggest that the osmoregulatory activities of GH had emerged in the basal chordate amphioxus. We also proposed a new model depicting the origin of pituitary hormone family in vertebrates.
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Affiliation(s)
- Mengyang Li
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China
- Institute for Translational Medicine, Qingdao University, Qingdao 266021, China
| | - Chengyan Jiang
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China
- College of Life Science and Technology, Hong He University, Mengzi, Yunnan 661100, China
| | - Yu Zhang
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China
- *Yu Zhang: and
| | - Shicui Zhang
- Laboratory for Evolution & Development, Institute of Evolution & Marine Biodiversity and Department of Marine Biology, Ocean University of China, Qingdao 266003, China
- *Shicui Zhang:
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Mu X, Su M, Gui L, Liang X, Zhang P, Hu P, Liu Z, Zhang J. Comparative renal gene expression in response to abrupt hypoosmotic shock in spotted scat (Scatophagus argus). Gen Comp Endocrinol 2015; 215:25-35. [PMID: 25304824 DOI: 10.1016/j.ygcen.2014.09.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 09/17/2014] [Accepted: 09/20/2014] [Indexed: 11/18/2022]
Abstract
Scatophagus argus, a euryhaline fish, is notable for its ability to tolerate a wide range of environmental salinities and especially for its tolerance to a rapid, marked reduction in salinity. Therefore, S. argus is a good model for studying the molecular mechanisms mediating abrupt hyperosmoregulation. The serum osmotic pressure decreased steeply within one hour after transferring S. argus from seawater (SW) to freshwater (FW) and remained at new balance throughout the duration of one week. To explain this phenomenon and understand the molecular responses to an abrupt hypoosmotic shock, hypoosmotic stress responsive genes were identified by constructing two suppression subtractive hybridization (SSH) cDNA libraries from the kidneys of S. argus that had been transferred from SW to FW. After trimming and blasting, 52 ESTs were picked out from the subtractive library. Among them, 11 genes were significantly up-regulated (p < 0.05). The kinetics studies of gene expression levels were conducted for 1 week after the transfer using quantitative real-time PCR. A significant variation in the expression of these genes occurred within 12h after the hypoosmotic shock, except for growth hormone (GH) and polyadenylate binding protein 1 (PBP1), which were significantly up-regulated 2 days post-transfer. Our results suggest different functional roles for these genes in response to hypoosmotic stress during the stress response phase (1 hpt-12 hpt) and stable phase (12 hpt-7 dpt). Furthermore, the plasma growth hormone level was detected to be significantly elevated at 1 hpt and 24 hpt following abrupt hypoosmotic shock. Meanwhile, several hematological parameters, hemoglobin (HGB), red blood cell (RBC) and mean cellular hemoglobin concentration (MCHC), were observed to be significantly increased at 12 hpt and 2 dpt compared with that of control group. Our results provide a solid basis from which to conduct future studies on the osmoregulatory mechanisms in the euryhaline fish.
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Affiliation(s)
- Xingjiang Mu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Maoliang Su
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Lang Gui
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Xuemei Liang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Peipei Zhang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Pan Hu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Zhenhao Liu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Junbin Zhang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China.
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Breves JP, Seale AP, Moorman BP, Lerner DT, Moriyama S, Hopkins KD, Grau EG. Pituitary control of branchial NCC, NKCC and Na+, K+-ATPase α-subunit gene expression in Nile tilapia, Oreochromis niloticus. J Comp Physiol B 2014; 184:513-23. [DOI: 10.1007/s00360-014-0817-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 02/03/2014] [Accepted: 02/12/2014] [Indexed: 10/25/2022]
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Mousa MA, Khalil NA, Amal M. Hashem AM. Immunocytochemical identification and distribution of the cell types in the pituitary gland of <i>Bagrus bayad</i> (<i>Teleostei, Bagridae</i>). ACTA ACUST UNITED AC 2012. [DOI: 10.4236/wjns.2012.21004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Velan A, Hulata G, Ron M, Cnaani A. Comparative time-course study on pituitary and branchial response to salinity challenge in Mozambique tilapia (Oreochromis mossambicus) and Nile tilapia (O. niloticus). FISH PHYSIOLOGY AND BIOCHEMISTRY 2011; 37:863-73. [PMID: 21461902 DOI: 10.1007/s10695-011-9484-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 03/23/2011] [Indexed: 05/22/2023]
Abstract
The physiological response of Mozambique and Nile tilapia transferred from fresh to brackish (15 ppt) water was compared during a one-week time course. Response in the pituitary was measured by the gene expression pattern of prolactin (PRL I), growth hormone (GH), and calcium-sensing receptor (CaSR), while the response in the gills was measured by the gene expression pattern of the prolactin receptor (PRL-R), Na(+)/K(+)/2Cl(-) cotransporter (NKCC) and Na(+)/Cl(-) cotransporter (NCC), and by activity and expression of Na(+)/K(+)-ATPase (NKA). The time-course curves of plasma osmolality levels indicate a rapid elevation 24 h after transfer, which later decreased and maintained at stable level. PRL I expression decreased in both species, but with stronger response in the Nile tilapia, while no differences were found in the slightly elevated levels of GH mRNA. The branchial response demonstrated a faster up-regulation of NKA and NKCC in the Mozambique tilapia, but similar levels after a week, while Nile tilapia had stronger and constant down-regulation of NCC. The time-course response of the measured osmoregulatory parameters indicate that 24 h after transfer is a critical time point for brackish-water adaptation. The differences in responses to saltwater challenge between Mozambique and Nile tilapia shown in this study may be associated with the differences in saltwater tolerance between these two tilapiine species.
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Affiliation(s)
- Ariel Velan
- Institute of Animal Science, Agricultural Research Organization, Bet Dagan, Israel
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Breves JP, Seale AP, Helms RE, Tipsmark CK, Hirano T, Grau EG. Dynamic gene expression of GH/PRL-family hormone receptors in gill and kidney during freshwater-acclimation of Mozambique tilapia. Comp Biochem Physiol A Mol Integr Physiol 2010; 158:194-200. [PMID: 21056111 DOI: 10.1016/j.cbpa.2010.10.030] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 10/26/2010] [Accepted: 10/26/2010] [Indexed: 12/12/2022]
Abstract
In teleosts, prolactin (PRL) and growth hormone (GH) act at key osmoregulatory tissues to regulate hydromineral balance. This study was aimed at characterizing patterns of expression for genes encoding receptors for the GH/PRL-family of hormones in the gill and kidney of Mozambique tilapia (Oreochromis mossambicus) during freshwater (FW)-acclimation. Transfer of seawater (SW)-acclimated tilapia to FW elicited rapid and sustained increases in plasma levels and pituitary gene expression of PRL177 and PRL188; plasma hormone and pituitary mRNA levels of GH were unchanged. In the gill, PRL receptor 1 (PRLR1) mRNA increased markedly after transfer to FW by 6h, while increases in GH receptor (GHR) mRNA were observed 48 h and 14 d after the transfer. By contrast, neither PRLR2 nor the somatolactin receptor (SLR) was responsive to FW transfer. Paralleling these endocrine responses were marked increases in branchial gene expression of a Na+/Cl- cotransporter and a Na+/H+ exchanger, indicators of FW-type mitochondrion-rich cells (MRCs), at 24 and 48 h after FW transfer, respectively. Expression of Na+/K+/2Cl- cotransporter, an indicator of SW-type MRCs, was sharply down-regulated by 6h after transfer to FW. In kidney, PRLR1, PRLR2 and SLR mRNA levels were unchanged, while GHR mRNA was up-regulated from 6h after FW transfer to all points thereafter. Collectively, these results suggest that the modulation of the gene expression for PRL and GH receptors in osmoregulatory tissues represents an important aspect of FW-acclimation of tilapia.
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Affiliation(s)
- Jason P Breves
- Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, USA
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Breves JP, Hasegawa S, Yoshioka M, Fox BK, Davis LK, Lerner DT, Takei Y, Hirano T, Grau EG. Acute salinity challenges in Mozambique and Nile tilapia: differential responses of plasma prolactin, growth hormone and branchial expression of ion transporters. Gen Comp Endocrinol 2010; 167:135-42. [PMID: 20138183 DOI: 10.1016/j.ygcen.2010.01.022] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 01/21/2010] [Accepted: 01/31/2010] [Indexed: 11/17/2022]
Abstract
The responses of Mozambique and Nile tilapia acclimated to fresh water (FW) and brackish water (BW; 17 per thousand) were compared following acute salinity challenges. In both species, plasma osmolality increased to above 450 mOsm by 2h after transfer from FW to seawater (SW); these increases in osmolality were accompanied by unexpected increases in plasma prolactin (PRL). Likewise, PRL receptor gene expression in the gill also increased in both species. In Nile tilapia, hyperosmotic transfers (FW to BW and SW) resulted in increased plasma growth hormone (GH) and in branchial GH receptor gene expression, responses that were absent in Mozambique tilapia. Branchial gene expression of osmotic stress transcription factor 1 (OSTF1) increased in both species following transfer from FW to SW, whereas transfer from BW to SW induced OSTF1 expression only in the Nile tilapia. Branchial expression of Na(+)/Cl(-) cotransporter was higher in FW in both species than in BW. Branchial gene expression of Na(+)/K(+)/2Cl(-) cotransporter (NKCC) increased after transfer from BW to SW in Mozambique tilapia, whereas expression was reduced in the Nile tilapia following the same transfer. The difference in the SW adaptability of these species may be related to a limited capacity of Nile tilapia to up-regulate NKCC gene expression, which is likely to be an essential component in the recruitment of SW-type chloride cells. The differential responses of GH and OSTF1 may also be associated with the disparate SW adaptability of these two tilapiine species.
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Affiliation(s)
- J P Breves
- Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, USA
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Reinecke M. Influences of the environment on the endocrine and paracrine fish growth hormone-insulin-like growth factor-I system. JOURNAL OF FISH BIOLOGY 2010; 76:1233-54. [PMID: 20537012 DOI: 10.1111/j.1095-8649.2010.02605.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Insulin-like growth factor-I (IGF-I) is a key component of the complex system that regulates differentiation, development, growth and reproduction of fishes. The IGF-I gene is mainly expressed in the liver that represents the principal source of endocrine IGF-I but also in numerous other organs where the hormone most probably acts in an autocrine-paracrine manner. The primary stimulus for synthesis and release of IGF-I is growth hormone (GH) from the anterior pituitary. Thus, in analogy to mammals, it is usual to speak of a fish 'GH-IGF-I axis'. The GH-IGF-I system is affected by changes in the environment and probably represents a target of endocrine disrupting compounds (EDC) that impair many physiological processes in fishes. Thus, the review deals with the influences of changes in different environmental factors, such as food availability, temperature, photoperiod, season, salinity and EDCs, on GH gene expression in pituitary, IGF-I gene expression in liver and extrahepatic sites and the physiological effects resulting from the evoked alterations in endocrine and local IGF-I. Environmental influences certainly interact with each other but for convenience of the reader they will be dealt with in separate sections. Current trends in GH-IGF-I research are analysed and future focuses are suggested at the end of the sections.
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Affiliation(s)
- M Reinecke
- Division of Neuroendocrinology, Institute of Anatomy, University of Zürich, Winterthurerstr. 190, 8057 Zürich, Switzerland.
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Jackson LF, McCormick SD, Madsen SS, Swanson P, Sullivan CV. Osmoregulatory effects of hypophysectomy and homologous prolactin replacement in hybrid striped bass. Comp Biochem Physiol B Biochem Mol Biol 2005; 140:211-8. [PMID: 15649768 DOI: 10.1016/j.cbpc.2004.10.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2004] [Revised: 10/04/2004] [Accepted: 10/05/2004] [Indexed: 11/27/2022]
Abstract
The effects of ovine prolactin (oPRL) and striped bass prolactin (sbPRL; Morone saxatilis) on plasma osmolality, electrolyte balance, and gill Na(+),K(+)-ATPase activity were investigated in hypophysectomized (Hx), freshwater (FW)-acclimated, hybrid striped bass (M. saxatilisxMorone chrysops). They were kept in dilute (isoosmotic) seawater for about 10 days after surgery. Seven days after transfer to FW, Hx fish had lower plasma osmolality and lower levels of Na(+), Cl(-), and Ca(2+) than sham-operated and intact fish. Fish were injected four times with oPRL (1, 5, or 20 microg/g body mass), sbPRL (10 or 100 ng/g), or hormone vehicle (0.9% NaCl) at 48-h intervals (days 0, 2, 4, and 6) in FW and then sampled for blood plasma 24 h after the fourth injection (day 7). In Hx fish, oPRL (5 and 20 microg/g) and sbPRL (10 and 100 ng/g) were effective in maintaining plasma osmolality and levels of Na(+), Cl(-), and Ca(2+) above values seen in saline-injected controls. Hypophysectomy did not affect branchial Na(+),K(+)-ATPase activity, but enzyme activity was significantly reduced in Hx fish receiving oPRL (20 mug/g) or sbPRL (10 or 100 ng/g). These results indicate that PRL acts to maintain plasma osmotic and ionic balance in FW-adapted hybrid striped bass, and that this may involve downregulation of branchial Na(+),K(+)-ATPase activity.
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Affiliation(s)
- Leslie F Jackson
- Department of Zoology, North Carolina State University, Raleigh, NC 27695-7617, USA.
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Leena S, Oommen OV. Hormonal control on enzymes of osmoregulation in a teleost, Anabas testudineus (BLOCH): an in vivo and in vitro study. Endocr Res 2000; 26:169-87. [PMID: 10921446 DOI: 10.3109/07435800009066160] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Hormonal control of osmoregulation in teleosts is not well understood. Role of cGH, oGH, PRL, T3 and insulin on gill Na+,K+-ATPase, Mg2+ and Ca2+ ATPases was studied in A. testudineus. Short term administration of cGH, PRL or T3 significantly increased Na+,K+-ATPase, Mg2+ and Ca2+ ATPases, while oGH influenced only Mg2+ ATPase, and insulin stimulated Na+,K+-ATPase. Long-term treatment with cGH and PRL also significantly increased Na+,K+-ATPase activity. GH had an additive with T3 on stimulating Na+,K+-ATPase activity. In vitro addition of cGH and oGH also had definite stimulatory effect on gill Na+,K+-ATPase except for 2ng oGH. Bromocryptine treatment caused a significant reduction on Na+,K+-ATPase activity. Both in vivo and in vitro treatments of cGH and PRL independently reversed the action of bromocryptine on Na+,K+-ATPase. Combined treatment of cGH+PRL was more prominent in stimulating Na+,K+-ATPase in bromocryptine treated fish. Present study reveals that GH, PRL and T3 have definite regulatory role on enzymes of osmoregulation in the teleost Anabas testudineus.
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Affiliation(s)
- S Leena
- Department of Zoology, University of Kerala, Trivandrum, India
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Mousa SA, Mousa MA. Immunocytochemical and histological studies on the hypophyseal-gonadal system in the freshwater nile tilapia, oreochromis niloticus (L.), during sexual maturation and spawning in different habitats. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1999; 284:343-54. [PMID: 10404126 DOI: 10.1002/(sici)1097-010x(19990801)284:3<343::aid-jez12>3.0.co;2-v] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The activities of the hypophyseal-gonadal system of O. niloticus in different habitats were investigated using immunocytochemical and histological techniques. The observed physico-chemical results indicated that Lake Nasser water characteristics are within the allowed and desired safety baseline levels. In contrast, Lake Manzalah exhibited high levels of Ca(2+), Mg(2+), SO(4)(2-) and heavy metals (Zn, Pb, and Cd). These water conditions affected the activity of the hypophyseal-gonadal axis of tilapia. The secretory and the synthetic activities of GTH and SL cells in the pituitary gland, in general, underwent obvious normal changes during gonad maturation and spawning of O. niloticus in Lake Nasser. In Lake Manzalah, the secretory activity of GTH and SL cells declined. This may be due to the effect of the high levels of heavy metals which interfere with the release of hormones and disturb the feedback mechanisms. In addition, the activity of both PRL and GH cells in Lake Nasser was higher than that of Lake Manzalah, but the synthetic activity of the ACTH and MSH cells was higher in Lake Manzalah. This may be related to the increased stress on fishes and the dark polluted water in Lake Manzalah. Both the environmental and the endocrine impacts in Lake Manzalah caused a decline in the gonadal activity as reflected by the decrease of sperm amount in the ripe testis, the appearance of oocytes in the testis and the degeneration of ripe oocytes (atresia) during the spawning season. J. Exp. Zool. 284:343-354, 1999. Copyright 1999 Wiley-Liss, Inc.
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Affiliation(s)
- SA Mousa
- Zoology Department, Faculty of Science at Aswan, South Valley University, Aswan, Egypt
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Mancera JM, McCormick SD. Osmoregulatory actions of the GH/IGF axis in non-salmonid teleosts. Comp Biochem Physiol B Biochem Mol Biol 1998. [DOI: 10.1016/s0305-0491(98)10112-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mancera JM, McCormick SD. Evidence for growth hormone/insulin-like growth factor I axis regulation of seawater acclimation in the euryhaline teleost Fundulus heteroclitus. Gen Comp Endocrinol 1998; 111:103-12. [PMID: 9679082 DOI: 10.1006/gcen.1998.7086] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The ability of ovine growth hormone (oGH), recombinant bovine insulin-like growth factor I (rbIGF-I), recombinant human insulin-like growth factor II (rhIGF-II), and bovine insulin to increase hypoosmoregulatory capacity in the euryhaline teleost Fundulus heteroclitus was examined. Fish acclimated to brackish water (BW, 10 ppt salinity, 320 mOsm/kg H2O) were injected with a single dose of hormone and transferred to seawater (SW, 35 ppt salinity, 1120 mOsm/kg H2O) 2 days later. Fish were sampled 24 h after transfer and plasma osmolality, plasma glucose, and gill Na+, K+-ATPase activity were examined. Transfer from BW to SW increased plasma osmolality and gill Na+,K+-ATPase activity. Transfer from BW to BW had no effect on these parameters. rbIGF-I (0.05, 0.1, and 0.2 microg/g) improved the ability to maintain plasma osmolality and to increase gill Na+, K+-ATPase activity in a dose-dependent manner. oGH (0.5, 1, and 2 microg/g) also increased hypoosmoregulatory ability but only the higher doses (2 microg/g) significantly increased gill Na+,K+-ATPase activity. oGH (1 microg/g) and rbIGF-I (0.1 microg/g) had a significantly greater effect on plasma osmolality and gill Na+,K+-ATPase activity than either hormone alone. rhIGF-II (0.05, 0.1, and 0.2 microg/g) and bovine insulin (0.01 and 0.05 microg/g) were without effect. The results suggest a role of GH and insulin-like growth factor I (IGF-I) in seawater acclimation of F. heteroclitus. Based on these findings and previous studies, it is concluded that the capacity of the GH/IGF-I axis to increase hypoosmoregulatory ability may be a common feature of euryhalinity in teleosts.
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Affiliation(s)
- J M Mancera
- Departamento de Biología Animal, Facultad de Ciencias del Mar, Universidad de Cádiz, Puerto Real, Cádiz, 11510, Spain
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Nakano K, Tagawa M, Takemura A, Hirano T. Temporal changes in liver carbohydrate metabolism associated with seawater transfer in Oreochromis mossambicus. Comp Biochem Physiol B Biochem Mol Biol 1998. [DOI: 10.1016/s0305-0491(98)00048-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Physiological and Respiratory Responses of the Mozambique Tilapia (Oreochromis mossambicus) to Salinity Acclimation. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0300-9629(96)00261-7] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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Sakamoto T, Shepherd BS, Madsen SS, Nishioka RS, Siharath K, Richman NH, Bern HA, Grau EG. Osmoregulatory actions of growth hormone and prolactin in an advanced teleost. Gen Comp Endocrinol 1997; 106:95-101. [PMID: 9126469 DOI: 10.1006/gcen.1996.6854] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To date, growth hormone (GH) is known to contribute to seawater adaptation only in salmonid fishes (primitive Euteleostei). Accordingly, the effects of homologous GH and two forms of homologous prolactin (PRL177 and PRL188) on hypoosmoregulatory ability and gill Na+,K(+)-ATPase activity in a more advanced euryhaline cichlid fish, the tilapia (Oreochromis mossambicus), were examined. Following adaptation of hypophysectomized fish to 25% seawater for 3 weeks, fish were given four injections of hormone or vehicle. They were then exposed to 100% seawater for 12 hr and examined for changes in plasma osmolality. Tilapia GH (0.02 and 0.2 microgram/g) significantly improved the ability of tilapia to decrease plasma osmolality following transfer to full-strength seawater, in a dose-related manner. Growth hormone treatment also significantly stimulated gill Na+,K(+)-ATPase activity (0.5 microgram/g). Both tilapia PRLs (PRL177 and PRL188) increased plasma osmolality in 100% seawater and reduced gill Na+,K(+)-ATPase activity, the effects induced by PRL188 being more significant than those by PRL177. Thus, GH may be involved in seawater adaptation of tilapia, a species belonging to the most advanced teleost super-order (Acanthopterygii), whereas both PRLs in tilapia are not involved in seawater adaptation.
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Affiliation(s)
- T Sakamoto
- Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe 96744, USA
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