1
|
Sunga J, Wilson JM, Wilkie MP. Functional re-organization of the gills of metamorphosing sea lamprey (Petromyzon marinus): preparation for a blood diet and the freshwater to seawater transition. J Comp Physiol B 2020; 190:701-715. [PMID: 32852575 DOI: 10.1007/s00360-020-01305-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 05/31/2020] [Accepted: 06/18/2020] [Indexed: 11/28/2022]
Abstract
Sea lamprey (Petromyzon marinus) begin life as filter-feeding larvae (ammocoetes) before undergoing a complex metamorphosis into parasitic juveniles, which migrate to the sea where they feed on the blood of large-bodied fishes. The greater protein intake during this phase results in marked increases in the production of nitrogenous wastes (N-waste), which are excreted primarily via the gills. However, it is unknown how gill structure and function change during metamorphosis and how it is related to modes of ammonia excretion, nor do we have a good understanding of how the sea lamprey's transition from fresh water (FW) to sea water (SW) affects patterns and mechanisms of N-waste excretion in relation to ionoregulation. Using immunohistochemistry, we related changes in the gill structure of larval, metamorphosing, and juvenile sea lampreys to their patterns of ammonia excretion (Jamm) and urea excretion (Jurea) in FW, and following FW to artificial seawater (ASW) transfer. Rates of Jamm and Jurea were low in larval sea lamprey and increased in feeding juvenile, parasitic sea lamprey. In freshwater-dwelling ammocoetes, immunohistochemical analysis revealed that Rhesus glycoprotein C-like protein (Rhcg-like) was diffusely distributed on the lamellar epithelium, but following metamorphosis, Rhcg-like protein was restricted to SW mitochondrion-rich cells (MRCs; ionocytes) between the gill lamellae. Notably, these interlamellar Rhcg-like proteins co-localized with Na+/K+-ATPase (NKA), which increased in expression and activity by almost tenfold during metamorphosis. The distribution of V-type H+-ATPase (V-ATPase) on the lamellae decreased following metamorphosis, indicating it may have a more important role in acid-base regulation and Na+ uptake in FW, compared to SW. We conclude that the re-organization of the sea lamprey gill during metamorphosis not only plays a critical role in allowing them to cope with greater salinity following the FW-SW transition, but that it simultaneously reflects fundamental changes in methods used to excrete ammonia.
Collapse
Affiliation(s)
- Julia Sunga
- Department of Biology and Laurier Institute for Water Science, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
| | - Jonathan M Wilson
- Department of Biology and Laurier Institute for Water Science, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
| | - Michael P Wilkie
- Department of Biology and Laurier Institute for Water Science, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada.
| |
Collapse
|
2
|
Griffith MB, Lazorchak JM, Haring H. Uptake of Sulfate from Ambient Water by Freshwater Animals. WATER 2020; 12:1-1496. [PMID: 32704397 PMCID: PMC7376752 DOI: 10.3390/w12051496] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To better understand how the sulfate (SO4 2-) anion may contribute to the adverse effects associated with elevated ionic strength or salinity in freshwaters, we measured the uptake and efflux of SO4 2- in four freshwater species: the fathead minnow (Pimephales promelas, Teleostei: Cyprinidae), paper pondshell (Utterbackia imbecillis, Bivalvia: Unionidae), red swamp crayfish (Procambarus clarkii, Crustacea: Cambaridae), and two-lined mayfly (Hexagenia bilineata, Insecta: Ephemeridae). Using δ( 34 S/ 32 S) stable isotope ratios and the concentrations of S and SO4 2-, we measured the SO4 2- influx rate (J in ), net flux (J net ), and efflux rate (Jout) during a 24 h exposure period. For all four species, the means of J in for SO4 2- were positive, and J in was significantly greater than 0 at both target SO4 2- concentrations in the fish and mollusk and at the lower SO4 2- concentration in the crayfish. The means of J out and J net were much more variable than those for J in , but several species by target SO4 2- concentration combinations for J out and J net , were negative, which suggests the net excretion of SO4 2- by the animals. The results of our experiments suggest a greater regulation of SO4 2- in freshwater animals than has been previously reported.
Collapse
Affiliation(s)
- Michael B. Griffith
- U.S. Environmental Protection Agency, Office of Research and Development, National Center for Environmental Assessment, Cincinnati, OH 45268, USA
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Measurement and Modeling, Cincinnati, OH 45268, USA
| | - James M. Lazorchak
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Measurement and Modeling, Cincinnati, OH 45268, USA
- U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, Cincinnati, OH 45268, USA
| | - Herman Haring
- Pegasus Technical Services, Inc., Cincinnati, OH 45268, USA
| |
Collapse
|
3
|
Tseng YC, Yan JJ, Furukawa F, Hwang PP. Did Acidic Stress Resistance in Vertebrates Evolve as Na + /H + Exchanger-Mediated Ammonia Excretion in Fish? Bioessays 2020; 42:e1900161. [PMID: 32163625 DOI: 10.1002/bies.201900161] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 02/20/2020] [Indexed: 12/21/2022]
Abstract
How vertebrates evolved different traits for acid excretion to maintain body fluid pH homeostasis is largely unknown. The evolution of Na+ /H+ exchanger (NHE)-mediated NH4 + excretion in fishes is reported, and the coevolution with increased ammoniagenesis and accompanying gluconeogenesis is speculated to benefit vertebrates in terms of both internal homeostasis and energy metabolism response to acidic stress. The findings provide new insights into our understanding of the possible adaptation of fishes to progressing global environmental acidification. In human kidney, titratable H+ and NH4 + comprise the two main components of net acid excretion. V-type H+ -ATPase-mediated H+ excretion may have developed in stenohaline lampreys when they initially invaded freshwater from marine habitats, but this trait is lost in most fishes. Instead, increased reliance on NHE-mediated NH4 + excretion is gradually developed and intensified during fish evolution. Further investigations on more species will be needed to support the hypothesis. Also see the video abstract here https://youtu.be/vZuObtfm-34.
Collapse
Affiliation(s)
- Yung-Che Tseng
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Jia-Jiun Yan
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Fumiya Furukawa
- Kitasato University, School of Marine Biosciences, Tokyo, 2520373, Japan
| | - Pung-Pung Hwang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| |
Collapse
|
4
|
Al-Fifi ZI, Mujallid MI. Effect of circadian on the activities of ion transport ATPases and histological structure of kidneys in mice. Saudi J Biol Sci 2018; 26:963-969. [PMID: 31303826 PMCID: PMC6601028 DOI: 10.1016/j.sjbs.2018.06.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 06/17/2018] [Accepted: 06/27/2018] [Indexed: 02/07/2023] Open
Abstract
The impacts of unnatural every day cycles (circadian) for 60 days on the histological structure of kidneys and ATPase activities in MF1 mice were studied. The exposure times were 16 h dark, 16 h light, 24 h dark, and 24 h light, and control exposure times were 12 h dark followed by 12 h light. Our results showed an increase in the total ATPase activity of mice in all groups. Additionally, the activity of the enzyme Na+/K+-ATPase was increased after 24 h darkness, 24 h light, and 16 h light exposures compared to control. The enzyme Mg+2-ATPase activities of the groups were higher when exposed to 16 h light, 24 h light, 24 h darkness and 16 h darkness. The activities of total ATPase, Na+/K+-ATPase and Mg+2-ATPase in kidneys were increased in all groups after 24 h light, 24 h darkness, 16 h darkness and 16 h light exposures. Interestingly, the activity of V-type ATPase was reduced after 16 h darkness, 24 h darkness and 16 h light. Taking everything into account, changes in the day by day cycle prompt neurotic changes, enzymatic and histological changes in the kidneys of mice. More studies should be directed to explore the impacts of light and darkness that can prompt these progressions.
Collapse
Affiliation(s)
- Zarraq I Al-Fifi
- Department of Biology, Faculty of Science, Jazan University, Saudi Arabia
| | - Mohammad I Mujallid
- Department of Biology, Faculty of Science, King Abdulaziz University, Saudi Arabia
| |
Collapse
|
5
|
Zhang C, Wang H, Chen Z, Zhuang L, Xu L, Ning Z, Zhu Z, Wang P, Meng Z. Carbonic anhydrase 2 inhibits epithelial–mesenchymal transition and metastasis in hepatocellular carcinoma. Carcinogenesis 2018; 39:562-570. [DOI: 10.1093/carcin/bgx148] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Affiliation(s)
- Chenyue Zhang
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Haiyong Wang
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan, China
| | - Zhiao Chen
- Fudan University Shanghai Cancer Center and Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Liping Zhuang
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Litao Xu
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhouyu Ning
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhenfeng Zhu
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Peng Wang
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhiqiang Meng
- Department of Integrative Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| |
Collapse
|
6
|
Griffith MB. Toxicological perspective on the osmoregulation and ionoregulation physiology of major ions by freshwater animals: Teleost fish, crustacea, aquatic insects, and Mollusca. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2017; 36:576-600. [PMID: 27808448 PMCID: PMC6114146 DOI: 10.1002/etc.3676] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/11/2016] [Accepted: 11/01/2016] [Indexed: 05/21/2023]
Abstract
Anthropogenic sources increase freshwater salinity and produce differences in constituent ions compared with natural waters. Moreover, ions differ in physiological roles and concentrations in intracellular and extracellular fluids. Four freshwater taxa groups are compared, to investigate similarities and differences in ion transport processes and what ion transport mechanisms suggest about the toxicity of these or other ions in freshwater. Although differences exist, many ion transporters are functionally similar and may belong to evolutionarily conserved protein families. For example, the Na+ /H+ -exchanger in teleost fish differs from the H+ /2Na+ (or Ca2+ )-exchanger in crustaceans. In osmoregulation, Na+ and Cl- predominate. Stenohaline freshwater animals hyperregulate until they are no longer able to maintain hypertonic extracellular Na+ and Cl- concentrations with increasing salinity and become isotonic. Toxic effects of K+ are related to ionoregulation and volume regulation. The ionic balance between intracellular and extracellular fluids is maintained by Na+ /K+ -adenosine triphosphatase (ATPase), but details are lacking on apical K+ transporters. Elevated H+ affects the maintenance of internal Na+ by Na+ /H+ exchange; elevated HCO3- inhibits Cl- uptake. The uptake of Mg2+ occurs by the gills or intestine, but details are lacking on Mg2+ transporters. In unionid gills, SO42- is actively transported, but most epithelia are generally impermeant to SO42- . Transporters of Ca2+ maintain homeostasis of dissolved Ca2+ . More integration of physiology with toxicology is needed to fully understand freshwater ion effects. Environ Toxicol Chem 2017;36:576-600. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.
Collapse
Affiliation(s)
- Michael B. Griffith
- Office of Research and Development, National Center for Environmental Assessment, US Environmental Protection Agency, Cincinnati, Ohio, USA
| |
Collapse
|
7
|
Ferreira-Martins D, McCormick SD, Campos A, Lopes-Marques M, Osório H, Coimbra J, Castro LFC, Wilson JM. A cytosolic carbonic anhydrase molecular switch occurs in the gills of metamorphic sea lamprey. Sci Rep 2016; 6:33954. [PMID: 27703170 PMCID: PMC5050428 DOI: 10.1038/srep33954] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 09/05/2016] [Indexed: 01/12/2023] Open
Abstract
Carbonic anhydrase plays a key role in CO2 transport, acid-base and ion regulation and metabolic processes in vertebrates. While several carbonic anhydrase isoforms have been identified in numerous vertebrate species, basal lineages such as the cyclostomes have remained largely unexamined. Here we investigate the repertoire of cytoplasmic carbonic anhydrases in the sea lamprey (Petromyzon marinus), that has a complex life history marked by a dramatic metamorphosis from a benthic filter-feeding ammocoete larvae into a parasitic juvenile which migrates from freshwater to seawater. We have identified a novel carbonic anhydrase gene (ca19) beyond the single carbonic anhydrase gene (ca18) that was known previously. Phylogenetic analysis and synteny studies suggest that both carbonic anhydrase genes form one or two independent gene lineages and are most likely duplicates retained uniquely in cyclostomes. Quantitative PCR of ca19 and ca18 and protein expression in gill across metamorphosis show that the ca19 levels are highest in ammocoetes and decrease during metamorphosis while ca18 shows the opposite pattern with the highest levels in post-metamorphic juveniles. We propose that a unique molecular switch occurs during lamprey metamorphosis resulting in distinct gill carbonic anhydrases reflecting the contrasting life modes and habitats of these life-history stages.
Collapse
Affiliation(s)
- D. Ferreira-Martins
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR) Universidade do Porto, 4050-123, Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313, Porto, Portugal
| | - S. D. McCormick
- USGS, Leetown Science Center, S.O. Conte Anadromous Fish Research Laboratory, 01376, Turner Falls MA USA
| | - A. Campos
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR) Universidade do Porto, 4050-123, Porto, Portugal
| | - M. Lopes-Marques
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR) Universidade do Porto, 4050-123, Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313, Porto, Portugal
| | - H. Osório
- i3s-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto, 4200-135, Porto, Portugal
- Departamento de Patologia e Oncologia, Faculdade de Medicina, Universidade do Porto, 4200-319, Porto, Portugal
| | - J. Coimbra
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR) Universidade do Porto, 4050-123, Porto, Portugal
| | - L. F. C. Castro
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR) Universidade do Porto, 4050-123, Porto, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4169–007, Porto, Portugal
| | - J. M. Wilson
- Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR) Universidade do Porto, 4050-123, Porto, Portugal
- Department of Biology, Wilfrid Laurier University, N2L 3C5, Waterloo, Canada
| |
Collapse
|
8
|
Ferreira-Martins D, Coimbra J, Antunes C, Wilson JM. Effects of salinity on upstream-migrating, spawning sea lamprey, Petromyzon marinus. CONSERVATION PHYSIOLOGY 2016; 4:cov064. [PMID: 27293744 PMCID: PMC4765514 DOI: 10.1093/conphys/cov064] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 11/26/2015] [Indexed: 05/07/2023]
Abstract
The sea lamprey, Petromyzon marinus, is an anadromous, semelparous species that is vulnerable to endangered in parts of its native range due in part to loss of spawning habitat because of man-made barriers. The ability of lampreys to return to the ocean or estuary and search out alternative spawning river systems would be limited by their osmoregulatory ability in seawater. A reduction in tolerance to salinity has been documented in migrants, although the underlying mechanisms have not been characterized. We examined the capacity for marine osmoregulation in upstream spawning migrants by characterizing the physiological effects of salinity challenge from a molecular perspective. Estuarine-captured migrants held in freshwater (FW) for ∼1 week (short-term acclimation) or 2 months (long-term acclimation) underwent an incremental salinity challenge until loss of equilibrium occurred and upper thresholds of 25 and 17.5, respectively, occurred. Regardless of salinity tolerance, all lamprey downregulated FW ion-uptake mechanisms [gill transcripts of Na(+):Cl(-) cotransporter (NCC/slc12a3) and epithelial Na(+) channel (ENaC/scnn1) and kidney Na(+)/K(+)-ATPase (NKA) protein and activity but not transcript]. At their respective salinity limits, lamprey displayed a clear osmoregulatory failure and were unable to regulate [Na(+)] and [Cl(-)] in plasma and intestinal fluid within physiological limits, becoming osmocompromised. A >90% drop in haematocrit indicated haemolysis, and higher plasma concentrations of the cytosolic enzymes alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase indicated damage to other tissues, including liver. However, >80% of short-term FW-acclimated fish were able to osmoregulate efficiently, with less haemolysis and tissue damage. This osmoregulatory ability was correlated with significant upregulation of the secretory form of Na(+):K(+):2Cl(-) cotransporter (NKCC1/slc12a2) transcript levels and the re-emergence of seawater-type ionocytes detected through immunohistochemical NKA immunoreactivity in the gill, the central ionoregulatory organ. This work sheds light on the molecular and physiological limits to the potential return to seawater for lampreys searching for alternative FW systems in which to spawn.
Collapse
Affiliation(s)
- D. Ferreira-Martins
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar, ICBAS, Universidade do Porto, Porto, Portugal
| | - J. Coimbra
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar, ICBAS, Universidade do Porto, Porto, Portugal
| | - C. Antunes
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
- Aquamuseu do Rio Minho, Vila Nova de Cerveira, Portugal
| | - J. M. Wilson
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Porto, Portugal
- Department of Biology, Wilfrid Laurier University, Waterloo, Ontario, Canada
| |
Collapse
|
9
|
Edwards SL, Marshall WS. Principles and Patterns of Osmoregulation and Euryhalinity in Fishes. FISH PHYSIOLOGY 2012. [DOI: 10.1016/b978-0-12-396951-4.00001-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
|
10
|
Tse WK, Chow S, Lai K, Au D, Wong CK. Modulation of ion transporter expression in gill mitochondrion-rich cells of eels acclimated to low-Na+ or-Cl− freshwater. ACTA ACUST UNITED AC 2011; 315:385-93. [DOI: 10.1002/jez.681] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 12/28/2010] [Accepted: 02/16/2011] [Indexed: 11/09/2022]
|
11
|
Cramp RL, Hudson NJ, Franklin CE. Activity, abundance, distribution and expression of Na+/K+-ATPase in the salt glands of Crocodylus porosus following chronic saltwater acclimation. J Exp Biol 2010; 213:1301-8. [DOI: 10.1242/jeb.039305] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Saltwater crocodiles, Crocodylus porosus, possess lingual salt glands which function to remove excess Na+ and Cl− accumulated as a consequence of living in salt water. Little is known about the nature of ion transport systems in C. porosus salt glands and how these systems respond to an osmotic challenge. In the present study, we examined the distribution and regulation of the Na+/K+-ATPase (NKA) pump, specifically the α-(catalytic) subunit in the salt glands of C. porosus chronically acclimated (6 months) to freshwater (FW) or 70% seawater (SW). We hypothesised that in the SW-acclimated C. porosus there would be an up-regulation of the abundance, activity and gene expression of the NKA transporter. NKA was immunolocalised to the lateral and basal membrane of secretory cells. As predicted, the NKA α-subunit was 2-fold more abundant in SW-acclimated C. porosus salt glands. NKA gene expression was also elevated in the salt glands of SW- vs FW-acclimated crocodiles. There was no increase in the specific activity of NKA in SW-acclimated animals and the in vitro rate of oxygen consumption by salt gland slices from SW-acclimated animals was not significantly different from that of FW-acclimated animals. The proportion of tissue oxygen consumption rate attributable to NKA activity was not different between SW- and FW-acclimated animals (approximately 50%). These data suggest that either chronic SW acclimation does not affect NKA in crocodile salt glands in the same manner as seen in other models or crocodiles possess the capacity to moderate NKA activity following prolonged exposure to SW.
Collapse
Affiliation(s)
- Rebecca L. Cramp
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Nicholas J. Hudson
- CSIRO Livestock Industries, Queensland Bioscience Precinct, St Lucia, QLD 4067, Australia
| | - Craig E. Franklin
- School of Biological Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| |
Collapse
|
12
|
Abstract
SUMMARY
Carbonic anhydrase (CA) is the zinc metalloenzyme that catalyses the reversible reactions of CO2 with water. CA plays a crucial role in systemic acid–base regulation in fish by providing acid–base equivalents for exchange with the environment. Unlike air-breathing vertebrates, which frequently utilize alterations of breathing (respiratory compensation) to regulate acid–base status, acid–base balance in fish relies almost entirely upon the direct exchange of acid–base equivalents with the environment (metabolic compensation). The gill is the critical site of metabolic compensation, with the kidney playing a supporting role. At the gill, cytosolic CA catalyses the hydration of CO2 to H+ and HCO3– for export to the water. In the kidney, cytosolic and membrane-bound CA isoforms have been implicated in HCO3– reabsorption and urine acidification. In this review, the CA isoforms that have been identified to date in fish will be discussed together with their tissue localizations and roles in systemic acid–base regulation.
Collapse
Affiliation(s)
- K. M. Gilmour
- Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, ON, Canada
| | - S. F. Perry
- Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, ON, Canada
| |
Collapse
|
13
|
Reis-Santos P, McCormick SD, Wilson JM. Ionoregulatory changes during metamorphosis and salinity exposure of juvenile sea lamprey (Petromyzon marinus L.). ACTA ACUST UNITED AC 2008; 211:978-88. [PMID: 18310123 DOI: 10.1242/jeb.014423] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Ammocoetes of the anadromous sea lamprey Petromyzon marinus L. spend many years in freshwater before metamorphosing and migrating to sea. Metamorphosis involves the radical transformation from a substrate-dwelling, filter feeder into a free-swimming, parasitic feeder. In the present work we examined osmoregulatory differences between ammocoetes and transformers (metamorphic juveniles), and the effects of salinity acclimation. We measured the expression of key ion-transporting proteins [Na(+)/K(+)-ATPase, vacuolar (V)-type H(+)-ATPase and carbonic anhydrase (CA)] as well as a number of relevant blood parameters (hematocrit, [Na(+)] and [Cl(-)]). In addition, immunofluorescence microscopy was used to identify and characterize the distributions of Na(+)/K(+)-ATPase, V-type H(+)-ATPase and CA immunoreactive cells in the gill. Ammocoetes did not survive in the experiments with salinities greater than 10 per thousand, whereas survival in high salinity (> or =25-35 per thousand) increased with increased degree of metamorphosis in transformers. Plasma [Na(+)] and [Cl(-)] of ammocoetes in freshwater was lower than transformers and increased markedly at 10 per thousand. In transformers, plasma ions increased only at high salinity (>25 per thousand). Branchial Na(+)/K(+)-ATPase levels were approximately tenfold higher in transformers compared to ammocoetes and salinity did not affect expression in either group. However, branchial H(+)-ATPase expression showed a negative correlation with salinity in both groups. Na(+)/K(+)-ATPase immunoreactivity was strongest in transformers and associated with clusters of cells in the interlamellar spaces. H(+)-ATPase (B subunit) immunoreactivity was localized to epithelial cells not expressing high Na(+)/K(+)-ATPase immunoreactivity and having a similar tissue distribution as carbonic anhydrase. The results indicate that branchial Na(+)/K(+)-ATPase and salinity tolerance increase in metamorphosing lampreys, and that branchial H(+)-ATPase is downregulated by salinity.
Collapse
Affiliation(s)
- Patrick Reis-Santos
- Centro Interdiscplinar de Investigação Marinha e Ambiental, Rua dos Bragas 289, 4050-123 Porto, Portugal
| | | | | |
Collapse
|
14
|
Tresguerres M, Parks SK, Goss GG. Recovery from blood alkalosis in the Pacific hagfish (Eptatretus stoutii): Involvement of gill V–H+–ATPase and Na+/K+–ATPase. Comp Biochem Physiol A Mol Integr Physiol 2007; 148:133-41. [PMID: 17512231 DOI: 10.1016/j.cbpa.2007.03.032] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 03/26/2007] [Accepted: 03/30/2007] [Indexed: 10/23/2022]
Abstract
To investigate the base secretory mechanisms in the Pacific hagfish (Eptatretus stoutii), we injected animals with NaHCO3 into the subcutaneous sinus. In the first series of experiments, hagfish were injected with 6000 micromol kg(-1) NaHCO3 (base-infused hagfish, BIH) or NaCl (controls). Blood pH increased significantly 1 h after injection in BIH (8.05+/-0.05 vs. 7.82+/-0.03 pH units), but returned to control values by t=6 h. Plasma total CO2 (TCO2) followed the same pattern. Immunolabeled sections revealed that Na+/K+-ATPase and V-H+-ATPase were usually located in the same cells. Western blotting revealed that the abundance of both proteins remained unchanged in whole gill homogenates and in a fraction enriched in cell membranes 6 h after the injections. The second experimental series was to induce long-term alkalosis by serially injecting 6000 micromol kg(-1) NaHCO3 every 6 h for 24 h. Blood pH completely recovered from the base loads within 6 h after each injection. Moreover, plasma TCO2 was not elevated 3 h after the second infusion, suggesting that HCO3(-) secreting mechanisms had been upregulated by that time. Na+/K+-ATPase and V-H+-ATPase cellular localizations did not change in the 24 h base infusion protocol. Na+/K+-ATPase abundance was similar in gill homogenates from fish from both treatments. However, Na+/K+-ATPase abundance in the membrane fraction was significantly lower in BIH, while V-H+-ATPase was greater both in whole gill and membrane fractions. Our results suggest that differential insertion of V-H+-ATPase and Na+/K+-ATPase into the basolateral membrane is involved in recovering from alkalotic stress in hagfish.
Collapse
Affiliation(s)
- Martin Tresguerres
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T5G 2E9, Canada.
| | | | | |
Collapse
|
15
|
Grosell M, Gilmour KM, Perry SF. Intestinal carbonic anhydrase, bicarbonate, and proton carriers play a role in the acclimation of rainbow trout to seawater. Am J Physiol Regul Integr Comp Physiol 2007; 293:R2099-111. [PMID: 17761514 DOI: 10.1152/ajpregu.00156.2007] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abrupt transfer of rainbow trout from freshwater to 65% seawater caused transient disturbances in extracellular fluid ionic composition, but homeostasis was reestablished 48 h posttransfer. Intestinal fluid chemistry revealed early onset of drinking and slightly delayed intestinal water absorption that coincided with initiation of NaCl absorption and HCO(3)(-) secretion. Suggestive of involvement in osmoregulation, relative mRNA levels for vacuolar H(+)-ATPase (V-ATPase), Na(+)-K(+)-ATPase, Na(+)/H(+) exchanger 3 (NHE3), Na(+)-HCO(3)(-) cotransporter 1, and two carbonic anhydrase (CA) isoforms [a general cytosolic isoform trout cytoplasmic CA (tCAc) and an extracellular isoform trout membrane-bound CA type IV (tCAIV)], were increased transiently in the intestine following exposure to 65% seawater. Both tCAc and tCAIV proteins were localized to apical regions of the intestinal epithelium and exhibited elevated enzymatic activity after acclimation to 65% seawater. The V-ATPase was localized to both basolateral and apical regions and exhibited a 10-fold increase in enzymatic activity in fish acclimated to 65% seawater, suggesting a role in marine osmoregulation. The intestinal epithelium of rainbow trout acclimated to 65% seawater appears to be capable of both basolateral and apical H(+) extrusion, likely depending on osmoregulatory status and intestinal fluid chemistry.
Collapse
Affiliation(s)
- Martin Grosell
- Rosensteil School of Marine Atmospheric Sciences, University of Miami, FL 33149-1098, USA.
| | | | | |
Collapse
|
16
|
Choe KP, Edwards SL, Claiborne JB, Evans DH. The putative mechanism of Na+ absorption in euryhaline elasmobranchs exists in the gills of a stenohaline marine elasmobranch, Squalus acanthias. Comp Biochem Physiol A Mol Integr Physiol 2007; 146:155-62. [PMID: 17208025 DOI: 10.1016/j.cbpa.2006.09.027] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2006] [Revised: 09/11/2006] [Accepted: 09/28/2006] [Indexed: 11/24/2022]
Abstract
We recently cloned an NHE3 orthologue from the gills of the euryhaline Atlantic stingray (Dasyatis sabina), and generated a stingray NHE3 antibody to unequivocally localize the exchanger to the apical side of epithelial cells that are rich with Na(+)/K(+)-ATPase (A MRC). We also demonstrated an increase in NHE3 expression when stingrays are in fresh water, suggesting that NHE3 is responsible for active Na(+) absorption. However, the vast majority of elasmobranchs are only found in marine environments. In the current study, immunohistochemistry with the stingray NHE3 antibody was used to localize the exchanger in the gills of the stenohaline marine spiny dogfish shark (Squalus acanthias). NHE3 immunoreactivity was confined to the apical side of cells with basolateral Na(+)/K(+)-ATPase and was excluded from cells with high levels of vacuolar H(+)-ATPase. Western blots detected a single protein of 88 kDa in dogfish gills, the same size as NHE3 in stingrays and mammals. These immunological data demonstrate that the putative cell type responsible for active Na(+) absorption in euryhaline elasmobranchs is also present in stenohaline marine elasmobranchs, and suggest that the inability of most elasmobranchs to survive in fresh water is not due to a lack of the gill ion transporters for Na(+) absorption.
Collapse
Affiliation(s)
- Keith P Choe
- Department of Zoology, University of Florida, Gainesville, FL 32611, USA.
| | | | | | | |
Collapse
|
17
|
|
18
|
Tang CH, Lee TH. The novel correlation of carbonic anhydrase II and anion exchanger 1 in gills of the spotted green pufferfish,Tetraodon nigrovirids. ACTA ACUST UNITED AC 2007; 307:411-8. [PMID: 17530665 DOI: 10.1002/jez.391] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A novel relationship between branchial carbonic anhydrase II (CAII) and anion exchanger 1 (AE1) was investigated in the euryhaline spotted green pufferfish (Tetraodon nigroviridis). The immunoblots revealed that AE1 was only detected in the membrane fraction of gills while CAII can be probed both in the membrane and cytosol fractions of gills. CAII protein abundance in the membrane fraction is salinity dependent. Immunological detection of the membrane fraction CAII protein in gills showed 3.9-fold higher in the hyposmotic (freshwater) group than the hyperosmotic (seawater;35 per thousand) group. In contrast, there was no change in the protein level of cytosolic CAII between seawater and freshwater groups. The whole-mount immunocytochemical staining demonstrated that both AE1 and CAII were colocalized to the Na(+)/K(+)-ATPase-immunoreactive cells in gill epithelium of the pufferfish. The interaction between CAII and AE1 was further identified by co-immunoprecipitation because AE1 was detected in the immunoprecipitates of CAII and vice versa. Our results showed that in pufferfish gills CAII was not only expressed in the cytosol to produce the substrate for AE1 transport during Cl(-) influx but also associated with the plasma membrane via AE1. Obviously, it is essential for the physiological function of AE1 to interact with CAII in the membrane of gill Na(+)/K(+)-ATPase-immunoreactive cells. To our knowledge, this is the first study to demonstrate the interaction of branchial CAII and AE1 in fish. The novel correlation proposed a new model of Cl(-)/HCO(3) (-) transport in gills of the teleosts.
Collapse
Affiliation(s)
- C H Tang
- Department of Life Sciences, National Chung-Hsing University, Taichung, Taiwan
| | | |
Collapse
|
19
|
Tresguerres M, Parks SK, Goss GG. V-H+-ATPase, Na+/K+-ATPase and NHE2 immunoreactivity in the gill epithelium of the Pacific hagfish (Epatretus stoutii). Comp Biochem Physiol A Mol Integr Physiol 2006; 145:312-21. [PMID: 16945564 DOI: 10.1016/j.cbpa.2006.06.045] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2006] [Revised: 06/30/2006] [Accepted: 06/30/2006] [Indexed: 11/18/2022]
Abstract
We report the presence of the ion transporting proteins V-H(+)-ATPase, Na(+)/K(+)-ATPase and NHE2 in the gill epithelium of the Pacific hagfish Epatretus stoutii. Heterologous antibodies recognized single bands of the appropriate sizes for the three transporters in western blots. Immunohistochemical staining revealed that the distribution of labeled cells in the gill epithelium was identical for the three proteins. Immunopositive cells were most abundant in the primary filament from the afferent side of the gill pouch, and their number diminished towards the lamella. Na(+)/K(+)-ATPase-like immunoreactivity (L-IR) occurred throughout the cell cytoplasm, probably associated to the basolateral tubular system. V-H(+)-ATPase L-IR was similar to Na(+)/K(+)-ATPase, although some cells had slightly heavier staining in either the supra- or infra-nuclear region. NHE2 L-IR was also generally cytoplasmic, but a minority of the cells had stronger immunoreactivity in the apical region. In general, all three ion transporting proteins were localized in the same cells, as estimated from 4-microm immunostained consecutive sections. We hypothesize that these putative ion-transporting cells are involved in systemic acid/base regulation and discuss other possible roles. This is the first report of V-H(+)-ATPase in myxinoids, and the first NHE2 report in the Pacific hagfish.
Collapse
Affiliation(s)
- Martin Tresguerres
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T5G 2E9.
| | | | | |
Collapse
|
20
|
AL-Fifi Z. Studies of Some Molecular Properties of the Vacuolar H+-ATPase in Rainbow Trout (Oncorhynchus mykiss). ACTA ACUST UNITED AC 2006. [DOI: 10.3923/biotech.2006.455.460] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
21
|
Choe KP, Havird J, Rose R, Hyndman K, Piermarini P, Evans DH. COX2 in a euryhaline teleost, Fundulus heteroclitus: primary sequence, distribution, localization, and potential function in gills during salinity acclimation. J Exp Biol 2006; 209:1696-708. [PMID: 16621950 DOI: 10.1242/jeb.02198] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
In the kidneys of mammals, cyclooxygenase type 2 (COX2) is expressed in medullary interstitial cells, the macula densa and epithelial cells of the cortical thick ascending limb where it generates prostaglandins that regulate hormone secretion, inhibit ion transport, and support cell survival during salt loading and dehydration. In teleosts, the gills are in direct contact with an aquatic environment and are the dominant site of osmoregulation. During transfers between salinities, specialized cells in the gills (chloride cells) rapidly regulate NaCl secretion for systemic osmoregulation while they simultaneously are exposed to acute osmotic shock. This study was conducted to determine if COX2 is expressed in the gills, and if so, to evaluate its function in cellular and systemic osmoregulation. Degenerate primers, reverse transcription–PCR and rapid amplification of cDNA ends were used to deduce the complete cDNA sequence of a putative COX2 enzyme from the gills of the euryhaline killifish (Fundulus heteroclitus). The 2738 base pair cDNA includes a coding region for a 610 amino acid protein that is over 70%identical to mammalian COX2. A purified antibody generated against a conserved region of mouse COX2 labeled chloride cells, suggesting that the enzyme may control NaCl secretion as an autocrine agent. Real-time PCR was then used to demonstrate that mRNA expression of the COX2 homologue was threefold greater in gills from chronic seawater killifish than in gills from chronic freshwater killifish. Expression of Na+/K+/2Cl–cotransporter and the cystic fibrosis transmembrane conductance regulator were also greater in seawater, suggesting that chronic COX2 expression in the gills is regulated in parallel to the key ion transporters that mediate NaCl secretion. Real-time PCR was also used to demonstrate that acute transfer from seawater to freshwater and from freshwater to seawater led to rapid, transient inductions of COX2 expression. Together with previous physiological evidence,the present molecular and immunological data suggest that constitutive branchial COX2 expression is enhanced in seawater, where prostaglandins can regulate NaCl secretion in chloride cells. Our data also suggest that branchial COX2 expression may play a role in cell survival during acute osmotic shock.
Collapse
Affiliation(s)
- Keith P Choe
- Department of Zoology, University of Florida, Gainesville, 32611, USA.
| | | | | | | | | | | |
Collapse
|
22
|
Georgalis T, Perry SF, Gilmour KM. The role of branchial carbonic anhydrase in acid-base regulation in rainbow trout (Oncorhynchus mykiss). J Exp Biol 2006; 209:518-30. [PMID: 16424102 DOI: 10.1242/jeb.02018] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARYThe objective of the present study was to examine the branchial distribution of the recently identified rainbow trout cytoplasmic carbonic anhydrase isoform (tCAc) and to investigate its role in the regulation of acid-base disturbances in rainbow trout (Oncorhynchus mykiss). In situ hybridization using an oligonucleotide probe specific to tCAc revealed tCAc mRNA expression in both pavement cells and mitochondria-rich cells (chloride cells). Similarly, using a homologous polyclonal antibody,tCAc immunoreactivity was localized to pavement cells and mitochondria-rich cells in the interlamellar region and along the lamellae of the gills. Exposure of rainbow trout to hypercarbia (∼0.8% CO2) for 24 h resulted in significant increases in tCAc mRNA expression (∼20-fold;quantified by real-time PCR) and protein levels (∼1.3-fold; quantified by western analysis) but not enzyme activity (assessed on crude gill homogenates using the delta-pH CA assay). Inhibition of branchial CA activity in vivo using acetazolamide reduced branchial net acid excretion significantly by 20%. This effect was enhanced to a 36% reduction in branchial net acid excretion by subjecting the trout to hypercarbia (∼0.8%CO2) for 10 h prior to acetazolamide injection, an exposure that significantly increased branchial net acid excretion. The results of the present study support the widely held premise that branchial intracellular CA activity (tCAc) plays a key role in regulating acid-base balance in freshwater teleost fish.
Collapse
Affiliation(s)
- T Georgalis
- Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | | | | |
Collapse
|
23
|
Choe KP, Kato A, Hirose S, Plata C, Sindic A, Romero MF, Claiborne JB, Evans DH. NHE3 in an ancestral vertebrate: primary sequence, distribution, localization, and function in gills. Am J Physiol Regul Integr Comp Physiol 2005; 289:R1520-34. [PMID: 15994375 DOI: 10.1152/ajpregu.00048.2005] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In mammals, the Na+/H+ exchanger 3 (NHE3) is expressed with Na+/K+-ATPase in renal proximal tubules, where it secretes H+ and absorbs Na+ to maintain blood pH and volume. In elasmobranchs (sharks, skates, and stingrays), the gills are the dominant site of pH and osmoregulation. This study was conducted to determine whether epithelial NHE homologs exist in elasmobranchs and, if so, to localize their expression in gills and determine whether their expression is altered by environmental salinity or hypercapnia. Degenerate primers and RT-PCR were used to deduce partial sequences of mammalian NHE2 and NHE3 homologs from the gills of the euryhaline Atlantic stingray (Dasyatis sabina). Real-time PCR was then used to demonstrate that mRNA expression of the NHE3 homolog increased when stingrays were transferred to low salinities but not during hypercapnia. Expression of the NHE2 homolog did not change with either treatment. Rapid amplification of cDNA was then used to deduce the complete sequence of a putative NHE3. The 2,744-base pair cDNA includes a coding region for a 2,511-amino acid protein that is 70% identical to human NHE3 (SLC9A3). Antisera generated against the carboxyl tail of the putative stingray NHE3 labeled the apical membranes of Na+/K+-ATPase-rich epithelial cells, and acclimation to freshwater caused a redistribution of labeling in the gills. This study provides the first NHE3 cloned from an elasmobranch and is the first to demonstrate an increase in gill NHE3 expression during acclimation to low salinities, suggesting that NHE3 can absorb Na+ from ion-poor environments.
Collapse
Affiliation(s)
- Keith P Choe
- Department of Zoology, University of Florida, Gainesville, USA.
| | | | | | | | | | | | | | | |
Collapse
|