1
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Kembou-Ringert JE, Hotio FN, Steinhagen D, Thompson KD, Surachetpong W, Rakus K, Daly JM, Goonawardane N, Adamek M. Knowns and unknowns of TiLV-associated neuronal disease. Virulence 2024; 15:2329568. [PMID: 38555518 PMCID: PMC10984141 DOI: 10.1080/21505594.2024.2329568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 03/07/2024] [Indexed: 04/02/2024] Open
Abstract
Tilapia Lake Virus (TiLV) is associated with pathological changes in the brain of infected fish, but the mechanisms driving the virus's neuropathogenesis remain poorly characterized. TiLV establishes a persistent infection in the brain of infected fish even when the virus is no longer detectable in the peripheral organs, rendering therapeutic interventions and disease management challenging. Moreover, the persistence of the virus in the brain may pose a risk for viral reinfection and spread and contribute to ongoing tissue damage and neuroinflammatory processes. In this review, we explore TiLV-associated neurological disease. We discuss the possible mechanism(s) used by TiLV to enter the central nervous system (CNS) and examine TiLV-induced neuroinflammation and brain immune responses. Lastly, we discuss future research questions and knowledge gaps to be addressed to significantly advance this field.
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Affiliation(s)
- Japhette E. Kembou-Ringert
- Department of infection, immunity and Inflammation, Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Fortune N. Hotio
- Department of Animal Biology, Faculty of Science, University of Dschang, Dschang, Cameroon
| | - Dieter Steinhagen
- Fish Disease Research Unit, Institute for parasitology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Kim D. Thompson
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, UK
| | - Win Surachetpong
- Department of Veterinary Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand
| | - Krzysztof Rakus
- Department of Evolutionary Immunology, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Krakow, Poland
| | - Janet M. Daly
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK
| | - Niluka Goonawardane
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Mikolaj Adamek
- Fish Disease Research Unit, Institute for parasitology, University of Veterinary Medicine Hannover, Hannover, Germany
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2
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Leonard EM, Porteus CS, Brink D, Milsom WK. Fish gill chemosensing: knowledge gaps and inconsistencies. J Comp Physiol B 2024:10.1007/s00360-024-01553-5. [PMID: 38758303 DOI: 10.1007/s00360-024-01553-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 04/04/2024] [Indexed: 05/18/2024]
Abstract
In this review, we explore the inconsistencies in the data and gaps in our knowledge that exist in what is currently known regarding gill chemosensors which drive the cardiorespiratory reflexes in fish. Although putative serotonergic neuroepithelial cells (NEC) dominate the literature, it is clear that other neurotransmitters are involved (adrenaline, noradrenaline, acetylcholine, purines, and dopamine). And although we assume that these agents act on neurons synapsing with the NECs or in the afferent or efferent limbs of the paths between chemosensors and central integration sites, this process remains elusive and may explain current discrepancies or species differences in the literature. To date it has been impossible to link the distribution of NECs to species sensitivity to different stimuli or fish lifestyles and while the gills have been shown to be the primary sensing site for respiratory gases, the location (gills, oro-branchial cavity or elsewhere) and orientation (external/water or internal/blood sensing) of the NECs are highly variable between species of water and air breathing fish. Much of what has been described so far comes from studies of hypoxic responses in fish, however, changes in CO2, ammonia and lactate have all been shown to elicit cardio-respiratory responses and all have been suggested to arise from stimulation of gill NECs. Our view of the role of NECs is broadening as we begin to understand the polymodal nature of these cells. We begin by presenting the fundamental picture of gill chemosensing that has developed, followed by some key unanswered questions about gill chemosensing in general.
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Affiliation(s)
- Erin M Leonard
- Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Cosima S Porteus
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada.
| | - Deidre Brink
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
| | - William K Milsom
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
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3
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Jonz MG. Cell proliferation and regeneration in the gill : By. J Comp Physiol B 2024:10.1007/s00360-024-01548-2. [PMID: 38554225 DOI: 10.1007/s00360-024-01548-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/02/2024] [Accepted: 02/29/2024] [Indexed: 04/01/2024]
Abstract
Seminal studies from the early 20th century defined the structural changes associated with development and regeneration of the gills in goldfish at the gross morphological and cellular levels using standard techniques of light and electron microscopy. More recently, investigations using cell lineage tracing, molecular biology, immunohistochemistry and single-cell RNA-sequencing have pushed the field forward and have begun to reveal the cellular and molecular processes that orchestrate cell proliferation and regeneration in the gills. The gill is a multifunctional organ that mediates an array of important physiological functions, including respiration, ion regulation and excretion of waste products. It is comprised of unique cell types, such as pavement cells, ionocytes, chemoreceptors and undifferentiated stem or progenitor cells that regulate growth and replenish cell populations. The gills develop from the embryonic endoderm and are rich in cell types derived from the neural crest. The gills have the capacity to remodel themselves in response to environmental change, such as in the case of ionocytes, chemoreceptors and the interlamellar cell mass, and can completely regenerate gill filaments and lamellae. Both processes of remodeling and regeneration invariably involve cell proliferation. Although gill regeneration has been reported in only a limited number of fish species, the process appears to have many similarities to regeneration of other organs in fish and amphibians. The present article reviews the studies that have described gill development and growth, and that demonstrate a suite of genes, transcription factors and other proteins involved in cell proliferation and regeneration in the gills.
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Affiliation(s)
- Michael G Jonz
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt, Ottawa, ON, K1N 6N5, Canada.
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4
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Thermal acclimation and acute temperature effects on cardiac barostatic reflexes in rainbow trout (Oncorhynchus mykiss). J Therm Biol 2022; 109:103315. [DOI: 10.1016/j.jtherbio.2022.103315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 07/26/2022] [Accepted: 08/24/2022] [Indexed: 11/17/2022]
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5
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Expression of the Antimicrobial Peptide Piscidin 1 and Neuropeptides in Fish Gill and Skin: A Potential Participation in Neuro-Immune Interaction. Mar Drugs 2022; 20:md20020145. [PMID: 35200674 PMCID: PMC8879440 DOI: 10.3390/md20020145] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/09/2022] [Accepted: 02/14/2022] [Indexed: 12/12/2022] Open
Abstract
Antimicrobial peptides (AMPs) are found widespread in nature and possess antimicrobial and immunomodulatory activities. Due to their multifunctional properties, these peptides are a focus of growing body of interest and have been characterized in several fish species. Due to their similarities in amino-acid composition and amphipathic design, it has been suggested that neuropeptides may be directly involved in the innate immune response against pathogen intruders. In this review, we report the molecular characterization of the fish-specific AMP piscidin1, the production of an antibody raised against this peptide and the immunohistochemical identification of this peptide and enkephalins in the neuroepithelial cells (NECs) in the gill of several teleost fish species living in different habitats. In spite of the abundant literature on Piscidin1, the biological role of this peptide in fish visceral organs remains poorly explored, as well as the role of the neuropeptides in neuroimmune interaction in fish. The NECs, by their role as sensors of hypoxia changes in the external environments, in combination with their endocrine nature and secretion of immunomodulatory substances would influence various types of immune cells that contain piscidin, such as mast cells and eosinophils, both showing interaction with the nervous system. The discovery of piscidins in the gill and skin, their diversity and their role in the regulation of immune response will lead to better selection of these immunomodulatory molecules as drug targets to retain antimicrobial barrier function and for aquaculture therapy in the future.
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6
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Plaul SE, Díaz AO, Barbeito CG. Gill morphology and morphometry of the facultative air-breathing armoured catfish, Corydoras paleatus, in relation on aquatic respiration. JOURNAL OF FISH BIOLOGY 2021; 99:1318-1327. [PMID: 34180055 DOI: 10.1111/jfb.14837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 06/09/2021] [Accepted: 06/23/2021] [Indexed: 06/13/2023]
Abstract
The Neotropical armoured catfish Corydoras paleatus is a facultative air-breathing teleost commonly exported as ornamental fish. In this species, air breathing enables it to survive and inhabit freshwater environments with low oxygen levels. Therefore, it is important to analyse the gills from a morphological aspect and its dimensions in relation to body mass with reference to aquatic respiration. For that, the gills were analysed using a stereoscopic microscope for morphometric studies, and structural and ultrastructural studies were carried out to compare the four branchial arches. Furthermore, two immunohistochemical techniques were used to locate and identify the presence of a Na+ /K+ pump. The characterization of the potential for cell proliferation of this organ was assessed using an anti-PCNA antibody. The results show that gills of C. paleatus present some characteristics related to its diet and lifestyle, such as the limited development of gill rakers and the abundance of taste buds. In addition, other special features associated with the environment and bimodal breathing were observed: scarce and absent mucous cells (MCs) in the gill filaments and branchial lamellae, respectively, and the localization of mitochondria-rich cells (MRCs) covering the basal third of the branchial lamellae, which reduces the gill respiratory area. A peculiar finding in the gill epithelium of this armoured catfish was the presence of mononuclear cells with sarcomeres similar to myoid cells, whose functional importance should be determined in future studies. Finally, in C. paleatus, the interlamellar space of gill filaments is an important site for cell turnover and ionoregulation; the latter function is also performed by the branchial lamellae.
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Affiliation(s)
- Silvia E Plaul
- Laboratorio de Histología y Embriología Descriptiva, Experimental y Comparada, Facultad de Ciencias Veterinarias (FCV), Universidad Nacional de La Plata (UNLP), La Plata, Argentina
| | - Alcira O Díaz
- Laboratorio de Histología e Histoquímica, Departamento de Biología. Instituto de Investigaciones Marinas y Costeras (IIMyC), Facultad de Ciencias Exactas y Naturales, CONICET-UNMdP, Mar del Plata, Argentina
| | - Claudio G Barbeito
- Laboratorio de Histología y Embriología Descriptiva, Experimental y Comparada, Facultad de Ciencias Veterinarias (FCV), Universidad Nacional de La Plata (UNLP), La Plata, Argentina
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7
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Dakrory AI, Abdel-Kader TG, Hassan MM, Al-Malky GJ. Comparative anatomical studies on the cranial nerves of the fully formed embryos of the Nile tilapia Oreochromis niloticus (Ostiechthyes-Cichlidae). I. Nervus glossopharyngeus. BRAZ J BIOL 2021; 82:e245509. [PMID: 33978085 DOI: 10.1590/1519-6984.245509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 01/06/2021] [Indexed: 11/22/2022] Open
Abstract
The organization of the roots, ganglia and the peripheral distribution of the cranial nerves of the fully formed embryos of Oreochromis niloticus are examined in the transverse serial sections. These nerves carry fibers, which were also analyzed. The results of this study demonstrated that the glossopharyngeal nerve originates by means of only one root, which leaves the cranium through the glossopharyngeal foramen. This nerve gives fibers (visceromotor) to the first internal and external levator arcus branchialis muscles. There is a single epibranchial (petrosal) ganglion located extracranially. Nervus glossopharyngeus has three rami; pharyngeus, pretramticus and posttrematicus. The ramus pharyngeus carries only viscerosensory fibers; general for the pharyngeal epithelium and special ones for the pseudobranch. General viscerosensory fibers are also carried by rami pretrematicus and posttrematicus for the pharyngeal epithelial lining. The special sensory fibers are carried by the ramus pretrematicus for the taste buds and by ramus posttrematicus for the gill filaments. The ramus pretrematicus also carries visceromotor fibers for the first adductor arcus branchialis and to the first obliquus ventralis muscles.
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Affiliation(s)
- A I Dakrory
- Cairo University, Faculty of Science, Department of Zoology, Cairo, Egypt
| | - T G Abdel-Kader
- Taif University, College of Sciences, Department of Biology, Taif, Saudi Arabia.,Helwan University, Department of Zoology & Entomology, Faculty of Science, Cairo, Egypt
| | - M M Hassan
- Taif University, College of Sciences, Department of Biology, Taif, Saudi Arabia.,Ain-Shams University, Department of Zoology, Faculty of Science, Cairo, Egypt
| | - G J Al-Malky
- Taif University, College of Sciences, Department of Biology, Taif, Saudi Arabia
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8
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Armelin VA, Braga VHDS, Teixeira MT, Guagnoni IN, Wang T, Florindo LH. The nonpharmacological sequence method provides a reliable evaluation of baroreflex sensitivity in fish. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2021; 335:348-358. [PMID: 33503334 DOI: 10.1002/jez.2448] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/22/2020] [Accepted: 01/08/2021] [Indexed: 11/10/2022]
Abstract
The most commonly used technique to study the barostatic regulation of blood pressure in ectothermic vertebrates consists of determining the heart rate response to pharmacological manipulations of blood pressure, the so-called "Oxford method." Although well established, the Oxford method has some important limitations, such as induction of hypervolemia in small animals and undesired effects of vasoactive drugs on central and peripheral baroreflex components. As an alternative, the sequence method, which consists in the computerized evaluation of naturally-occurring baroreflex adjustments of heart rate without the need for pharmacological administrations, was developed to study baroreflexes. In the present study, we compare this sequence method with the Oxford technique in two teleost species with different life styles, and we assess the optimal software configuration for the employment of the sequence method in fish. Calculation of baroreflex gain through the sequence method was adequate and reliable when the software was configured to search for baroreflex sequences with a minimum length of three cardiac cycles with a delay of one cardiac cycle between fluctuations in mean ventral aortic blood pressure and reflex changes in pulse interval. When properly configured, the sequence and the Oxford methods yielded similar determinations of the baroreflex gain in fish.
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Affiliation(s)
- Vinicius A Armelin
- Department of Physiology, University of São Paulo (USP), São Paulo, SP, Brazil.,Department of Zoology and Botany, São Paulo State University (UNESP), São José do Rio Preto, SP, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT-FAPESP/CNPq), Rio Claro, SP, Brazil
| | - Victor H da Silva Braga
- Department of Zoology and Botany, São Paulo State University (UNESP), São José do Rio Preto, SP, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT-FAPESP/CNPq), Rio Claro, SP, Brazil
| | - Mariana T Teixeira
- Department of Zoology and Botany, São Paulo State University (UNESP), São José do Rio Preto, SP, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT-FAPESP/CNPq), Rio Claro, SP, Brazil
| | - Igor N Guagnoni
- Department of Zoology and Botany, São Paulo State University (UNESP), São José do Rio Preto, SP, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT-FAPESP/CNPq), Rio Claro, SP, Brazil
| | - Tobias Wang
- National Institute of Science and Technology in Comparative Physiology (INCT-FAPESP/CNPq), Rio Claro, SP, Brazil.,Section for Zoophysiology, Department of Bioscience, Aarhus University (AU), Aarhus, Denmark
| | - Luiz H Florindo
- Department of Zoology and Botany, São Paulo State University (UNESP), São José do Rio Preto, SP, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT-FAPESP/CNPq), Rio Claro, SP, Brazil.,Aquaculture Center (CAUNESP), São Paulo State University (UNESP), Jaboticabal, SP, Brazil
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9
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Pan W, Scott AL, Nurse CA, Jonz MG. Identification of oxygen-sensitive neuroepithelial cells through an endogenous reporter gene in larval and adult transgenic zebrafish. Cell Tissue Res 2021; 384:35-47. [PMID: 33404838 DOI: 10.1007/s00441-020-03307-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/17/2020] [Indexed: 11/28/2022]
Abstract
In teleost fish, specialized oxygen (O2) chemoreceptors, called neuroepithelial cells (NECs), are found in the gill epithelium in adults. During development, NECs are present in the skin before the formation of functional gills. NECs are known for retaining the monoamine neurotransmitter, serotonin (5-HT) and are conventionally identified through immunoreactivity with antibodies against 5-HT or synaptic vesicle protein (SV2). However, identification of NECs in live tissue and isolated cell preparations has been challenging due to the lack of a specific marker. The present study explored the use of the transgenic zebrafish, ETvmat2:GFP, which expresses green fluorescent protein (GFP) under the control of the vesicular monoamine transporter 2 (vmat2) regulatory element, to identify NECs. Using immunohistochemistry and confocal microscopy, we confirmed that the endogenous GFP in ETvmat2:GFP labelled serotonergic NECs in the skin of larvae and in the gills of adults. NECs of the gill filaments expressed a higher level of endogenous GFP compared with other cells. The endogenous GFP also labelled intrabranchial neurons of the gill filaments. Flow cytometric analysis demonstrated that filamental NECs could be distinguished from other dissociated gill cells based on high GFP expression alone. Acclimation to 2 weeks of severe hypoxia (PO2 = 35 mmHg) induced an increase in filamental NEC frequency, size and GFP gene expression. Here we present for the first time a transgenic tool that labels O2 chemoreceptors in an aquatic vertebrate and its use in high-throughput experimentation.
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Affiliation(s)
- Wen Pan
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON, K1N 6N5, Canada
| | - Angela L Scott
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, L8S 4K1, Canada
| | - Colin A Nurse
- Department of Biology, McMaster University, Hamilton, ON, L8S 4K1, Canada
| | - Michael G Jonz
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON, K1N 6N5, Canada.
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10
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Wood CM, Pelster B, Braz-Mota S, Val AL. Gills versus kidney for ionoregulation in the obligate air-breathing Arapaima gigas, a fish with a kidney in its air-breathing organ. J Exp Biol 2020; 223:jeb232694. [PMID: 32895323 DOI: 10.1242/jeb.232694] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 08/19/2020] [Indexed: 12/19/2022]
Abstract
In Arapaima gigas, an obligate air-breather endemic to ion-poor Amazonian waters, a large complex kidney runs through the air-breathing organ (ABO). Previous indirect evidence suggested that the kidney, relative to the small gills, may be exceptionally important in ionoregulation and nitrogen (N) waste excretion, with support of kidney function by direct O2 supply from the airspace. We tested these ideas by continuous urine collection and gill flux measurements in ∼700 g fish. ATPase activities were many-fold greater in kidney than gills. In normoxia, gill Na+ influx and efflux were in balance, with net losses of Cl- and K+ Urine flow rate (UFR, ∼11 ml kg-1 h-1) and urinary ions (< 0.2 mmol l-1) were exceptional, with [urine]:[plasma] ratios of 0.02-0.002 for K+, Na+, and Cl-, indicating strong reabsorption with negligible urinary ion losses. Urinary [ammonia] was very high (10 mmol l-1, [urine]:[plasma] ∼17) indicating strong secretion. The kidney accounted for 21-24% of N excretion, with ammonia dominating (95%) over urea-N through both routes. High urinary [ammonia] was coupled to high urinary [HCO3-]. Aerial hypoxia (15.3 kPa) and aerial hyperoxia (>40.9 kPa) had no effects on UFR, but both inhibited branchial Na+ influx, revealing novel aspects of the osmorespiratory compromise. Aquatic hypoxia (4.1 kPa), but not aquatic hyperoxia (>40.9 kPa), inhibited gill Na+ influx, UFR and branchial and urinary ammonia excretion. We conclude that the kidney is more important than gills in ionoregulation, and is significant in N excretion. Although not definitive, our results do not indicate direct O2 supply from the ABO for kidney function.
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Affiliation(s)
- Chris M Wood
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
- Department of Biology, McMaster University, Hamilton, ON, Canada L8S 4K1
| | - Bernd Pelster
- Institute of Zoology, University of Innsbruck, Innsbruck A-6020, Austria
- Center for Molecular Biosciences, University Innsbruck, Innsbruck A-6020, Austria
| | - Susana Braz-Mota
- Laboratory of Ecophysiology and Molecular Evolution, Brazilian National Institute for Research of the Amazon, Manaus 69080-971, Brazil
| | - Adalberto L Val
- Laboratory of Ecophysiology and Molecular Evolution, Brazilian National Institute for Research of the Amazon, Manaus 69080-971, Brazil
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11
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Cadiz L, Jonz MG. A comparative perspective on lung and gill regeneration. ACTA ACUST UNITED AC 2020; 223:223/19/jeb226076. [PMID: 33037099 DOI: 10.1242/jeb.226076] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The ability to continuously grow and regenerate the gills throughout life is a remarkable property of fish and amphibians. Considering that gill regeneration was first described over one century ago, it is surprising that the underlying mechanisms of cell and tissue replacement in the gills remain poorly understood. By contrast, the mammalian lung is a largely quiescent organ in adults but is capable of facultative regeneration following injury. In the course of the past decade, it has been recognized that lungs contain a population of stem or progenitor cells with an extensive ability to restore tissue; however, despite recent advances in regenerative biology of the lung, the signaling pathways that underlie regeneration are poorly understood. In this Review, we discuss the common evolutionary and embryological origins shared by gills and mammalian lungs. These are evident in homologies in tissue structure, cell populations, cellular function and genetic pathways. An integration of the literature on gill and lung regeneration in vertebrates is presented using a comparative approach in order to outline the challenges that remain in these areas, and to highlight the importance of using aquatic vertebrates as model organisms. The study of gill regeneration in fish and amphibians, which have a high regenerative potential and for which genetic tools are widely available, represents a unique opportunity to uncover common signaling mechanisms that may be important for regeneration of respiratory organs in all vertebrates. This may lead to new advances in tissue repair following lung disease.
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Affiliation(s)
- Laura Cadiz
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON, Canada, K1N 6N5
| | - Michael G Jonz
- Department of Biology, University of Ottawa, 30 Marie Curie Pvt., Ottawa, ON, Canada, K1N 6N5
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12
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Guagnoni IN, Armelin VA, da Silva Braga VH, Rantin FT, Florindo LH. Postprandial cardiorespiratory responses and the regulation of digestion-associated tachycardia in Nile tilapia (Oreochromis niloticus). J Comp Physiol B 2020; 191:55-67. [PMID: 33005989 DOI: 10.1007/s00360-020-01317-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 08/29/2020] [Accepted: 09/20/2020] [Indexed: 11/25/2022]
Abstract
Cardiorespiratory adjustments that occur after feeding are essential to supply the demands of digestion in vertebrates. The well-documented postprandial tachycardia is triggered by an increase in adrenergic activity and by non-adrenergic non-cholinergic (NANC) factors in mammals and crocodilians, while it is linked to a withdrawal of vagal drive and NANC factors in non-crocodilian ectotherms-except for fish, in which the sole investigation available indicated no participation of NANC factors. On the other hand, postprandial ventilatory adjustments vary widely among air-breathing vertebrates, with different species exhibiting hyperventilation, hypoventilation, or even no changes at all. Regarding fish, which live in an environment with low oxygen capacitance that requires great ventilatory effort for oxygen uptake, data on the ventilatory consequences of feeding are also scarce. Thus, the present study sought to investigate the postprandial cardiorespiratory adjustments and the mediation of digestion-associated tachycardia in the unimodal water-breathing teleost Oreochromis niloticus. Heart rate (fH), cardiac autonomic tones, ventilation rate (fV), ventilation amplitude, total ventilation and fH/fV variability were assessed both in fasting and digesting animals under untreated condition, as well as after muscarinic cholinergic blockade with atropine and double autonomic blockade with atropine and propranolol. The results revealed that digestion was associated with marked tachycardia in O. niloticus, determined by a reduction in cardiac parasympathetic activity and by circulating NANC factors-the first time such positive chronotropes were detected in digesting fish. Unexpectedly, postprandial ventilatory alterations were not observed, although digestion triggered mechanisms that were presumed to increase oxygen uptake, such as cardiorespiratory synchrony.
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Affiliation(s)
- Igor Noll Guagnoni
- Department of Zoology and Botany, Institute of Biosciences, Languages and Exact Sciences, São Paulo State University (UNESP), Rua Cristóvão Colombo, 2265, São José do Rio Preto, SP, 15054-000, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT, FAPESP/CNPq), São Paulo, Brazil
| | - Vinicius Araújo Armelin
- Department of Zoology and Botany, Institute of Biosciences, Languages and Exact Sciences, São Paulo State University (UNESP), Rua Cristóvão Colombo, 2265, São José do Rio Preto, SP, 15054-000, Brazil.,Department of Physiology, Institute of Biosciences, University of São Paulo (USP), Rua do Matão, Travessa 14, 321, São Paulo, SP, 05508-090, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT, FAPESP/CNPq), São Paulo, Brazil
| | - Victor Hugo da Silva Braga
- Department of Zoology and Botany, Institute of Biosciences, Languages and Exact Sciences, São Paulo State University (UNESP), Rua Cristóvão Colombo, 2265, São José do Rio Preto, SP, 15054-000, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT, FAPESP/CNPq), São Paulo, Brazil
| | - Francisco Tadeu Rantin
- Department of Physiological Sciences, Federal University of São Carlos (UFSCar), Rodovia Washington Luiz, km 235, São Carlos, SP, 13565‑905, Brazil.,National Institute of Science and Technology in Comparative Physiology (INCT, FAPESP/CNPq), São Paulo, Brazil
| | - Luiz Henrique Florindo
- Department of Zoology and Botany, Institute of Biosciences, Languages and Exact Sciences, São Paulo State University (UNESP), Rua Cristóvão Colombo, 2265, São José do Rio Preto, SP, 15054-000, Brazil. .,Aquaculture Center (CAUNESP), São Paulo State University (UNESP), Rodovia Prof. Paulo Donato Castellane, n/n, Jaboticabal, SP, 14884-900, Brazil. .,National Institute of Science and Technology in Comparative Physiology (INCT, FAPESP/CNPq), São Paulo, Brazil.
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13
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Wang X, Lv Y, Xie J, Li B, Zhou T, Chen Y, Chen Y, Song J. Brain regions of marine medaka activated by acute and short-term ocean acidification. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 720:137279. [PMID: 32145610 DOI: 10.1016/j.scitotenv.2020.137279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/10/2020] [Accepted: 02/11/2020] [Indexed: 05/28/2023]
Abstract
Altered behaviors have been reported in many marine fish following exposure to high CO2 concentrations. However, the mechanistic link between elevated CO2 and activation of brain regions in fish is unknown. Herein, we examined the relative quantification and location of c-Fos expression in marine medaka following acute (360 min) and short-term (7 d) exposure to CO2-enriched water (1000 ppm and 1800 ppm CO2). In the control and two treatment groups, pH was stable at 8.21, 7.92 and 7.64, respectively. After acute exposure to seawater acidified by enrichment with CO2, there was a clear upregulation of c-Fos protein in the medaka brain (P < 0.05). c-Fos protein expression peaked after 120 min exposure in the two treatment groups and thereafter began to decline. There were marked increases in c-Fos-labeling in the ventricular and periventricular zones of the cerebral hemispheres and the medulla oblongata. After 1800 ppm CO2 exposure for 7 d, medaka showed significant preference for dark zones during the initial 2 min period. c-Fos protein expression in the ventricular and periventricular zones of the diencephalon in medaka exposed to 1000 ppm and 1800 ppm CO2 were 0.51 ± 0.10 and 1.34 ± 0.30, respectively, which were significantly higher than controls (P < 0.05). Highest doublecortin protein expression occurred in theventricular zones of the diencephalon and mesencephalon. These findings suggest that the ventricular and periventricular zones of the cerebral hemispheres and the medulla oblongata of marine medaka are involved in rapid acid-base regulation. Prolonged ocean acidification may induce cell mitosis and differentiation in the adult medaka brain.
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Affiliation(s)
- Xiaojie Wang
- Institute for Marine Biosystem and Neurosciences, Shanghai Ocean University, Shanghai 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, China.
| | - Yutao Lv
- National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), China
| | - Jinling Xie
- National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), China
| | - Baolin Li
- National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), China
| | - Tangjian Zhou
- National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), China
| | - Yaqi Chen
- National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), China
| | - Yi Chen
- National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), China
| | - Jiakun Song
- Institute for Marine Biosystem and Neurosciences, Shanghai Ocean University, Shanghai 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China
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14
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Mierzwa AS, Nguyen F, Xue M, Jonz MG. Regeneration of the gill filaments and replacement of serotonergic neuroepithelial cells in adult zebrafish (Danio rerio). Respir Physiol Neurobiol 2020; 274:103366. [DOI: 10.1016/j.resp.2019.103366] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 12/29/2019] [Indexed: 01/05/2023]
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15
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Zaccone G, Cupello C, Capillo G, Kuciel M, Nascimento ALR, Gopesh A, Germanà GP, Spanò N, Guerrera MC, Aragona M, Crupi R, Icardo JM, Lauriano ER. Expression of Acetylcholine- and G protein coupled Muscarinic receptor in the Neuroepithelial cells (NECs) of the obligated air-breathing fish, Arapaima gigas (Arapaimatidae: Teleostei). ZOOLOGY 2020; 139:125755. [PMID: 32088527 DOI: 10.1016/j.zool.2020.125755] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 01/28/2020] [Accepted: 01/30/2020] [Indexed: 01/18/2023]
Abstract
The air-breathing specialization has evolved idependently in vertebrates, as many different organs can perfom gas exchange. The largest obligate air-breathing fish from South America Arapaima gigas breathe air using its gas bladder, and its dependence on air breathing increases during its growth. During its development, gill morphology shows a dramatic change, remodeling with a gradual reduction of gill lamellae during the transition from water breathing to air breathing . It has been suggested that in this species the gills remain the main site of O2 and CO2 sensing. Consistent with this, we demonstrate for the first time the occurrence of the neuroepithelial cells (NECs) in the glottis, and in the gill filament epithelia and their distal halves. These cells contain a broader spectrum of neurotransmitters (5-HT, acetylcholine, nNOS), G-protein subunits and the muscarininic receptors that are coupled to G proteins (G-protein coupled receptors). We report also for the first time the presence of G alpha proteins coupled with muscarinic receptors on the NECs, that are thought as receptors that initiate the cardiorespiratory reflexes in aquatic vertebrates. Based on the specific orientation in the epithelia and their closest vicinity to efferent vasculatures, the gill and glottal NECs of A. gigas could be regarded as potential O2 and CO2 sensing receptors. However, future studies are needed to ascertain the neurophysiological characterization of these cells.
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Affiliation(s)
- Giacomo Zaccone
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Polo Universitario dell'Annunziata, I-98168 Messina, Italy
| | - Camila Cupello
- Departamento de Zoologia, Instituto de Biologia, Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier, 524, 20550-900, Rio de Janeiro, Brazil
| | - Gioele Capillo
- Department of Veterinary Sciences, University of Messina, Viale dell'Annunziata, I-98168 Messina, Italy.
| | - Michal Kuciel
- Poison Information Centre, Department of Toxicology and Environmental Disease, Faculty of Medicine, Jagellonian University, Kpernika 15, 30-501 Krakòw, Poland
| | - Ana L R Nascimento
- Departamento de Histologia e Embriologia, Instituto de Biologia, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, 20551-030, Rio de Janeiro, Brazil
| | - Anita Gopesh
- Department of Zoology, University of Allahabad, Allahabad 211002, U.P., India
| | - Germana Patrizia Germanà
- Department of Veterinary Sciences, University of Messina, Viale dell'Annunziata, I-98168 Messina, Italy
| | - Nunziacarla Spanò
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Polo Universitario dell'Annunziata, I-98168 Messina, Italy
| | - Maria Cristina Guerrera
- Department of Veterinary Sciences, University of Messina, Viale dell'Annunziata, I-98168 Messina, Italy
| | - Marialuisa Aragona
- Department of Veterinary Sciences, University of Messina, Viale dell'Annunziata, I-98168 Messina, Italy
| | - Rosalia Crupi
- Department of Veterinary Sciences, University of Messina, Viale dell'Annunziata, I-98168 Messina, Italy
| | - Jose Manuel Icardo
- Department of Anatomy and Cell Biology, Poligono de Cazona, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - Eugenia Rita Lauriano
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale F. Stagno d'Alcontres 31, I-98166 Messina, Italy
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16
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Kolesnikova EE. Neurophysiological Mechanisms of Respiratory Activity in Cyclostomes and Fish during Aquatic Breathing. J EVOL BIOCHEM PHYS+ 2019. [DOI: 10.1134/s0022093019020017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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17
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Stolper J, Ambrosio EM, Danciu DP, Buono L, Elliott DA, Naruse K, Martínez-Morales JR, Marciniak-Czochra A, Centanin L. Stem cell topography splits growth and homeostatic functions in the fish gill. eLife 2019; 8:e43747. [PMID: 31090541 PMCID: PMC6534379 DOI: 10.7554/elife.43747] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 05/14/2019] [Indexed: 11/13/2022] Open
Abstract
While lower vertebrates contain adult stem cells (aSCs) that maintain homeostasis and drive un-exhaustive organismal growth, mammalian aSCs display mainly the homeostatic function. Here, we use lineage analysis in the medaka fish gill to address aSCs and report separate stem cell populations for homeostasis and growth. These aSCs are fate-restricted during the entire post-embryonic life and even during re-generation paradigms. We use chimeric animals to demonstrate that p53 mediates growth coordination among fate-restricted aSCs, suggesting a hierarchical organisation among lineages in composite organs like the fish gill. Homeostatic and growth aSCs are clonal but differ in their topology; modifications in tissue architecture can convert the homeostatic zone into a growth zone, indicating a leading role for the physical niche defining stem cell output. We hypothesise that physical niches are main players to restrict aSCs to a homeostatic function in animals with fixed adult size.
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Affiliation(s)
- Julian Stolper
- Centre for Organismal StudiesHeidelberg UniversityHeidelbergGermany
- Murdoch Children’s Research InstituteRoyal Children’s HospitalParkvilleAustralia
| | | | | | - Lorena Buono
- Centro Andaluz de Biología del DesarrolloUniversidad Pablo de OlavideSevilleSpain
| | - David A Elliott
- Murdoch Children’s Research InstituteRoyal Children’s HospitalParkvilleAustralia
| | - Kiyoshi Naruse
- Laboratory of BioresourcesNational Institute for Basic Biology, National Institutes of Natural SciencesOkazakiJapan
| | | | - Anna Marciniak-Czochra
- Institute of Applied MathematicsHeidelberg UniversityHeidelbergGermany
- Bioquant CenterHeidelberg UniversityHeidelbergGermany
| | - Lazaro Centanin
- Centre for Organismal StudiesHeidelberg UniversityHeidelbergGermany
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18
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Oldham T, Nowak B, Hvas M, Oppedal F. Metabolic and functional impacts of hypoxia vary with size in Atlantic salmon. Comp Biochem Physiol A Mol Integr Physiol 2019; 231:30-38. [DOI: 10.1016/j.cbpa.2019.01.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 01/19/2019] [Accepted: 01/21/2019] [Indexed: 10/27/2022]
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19
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Thomsen MT, Lefevre S, Nilsson GE, Wang T, Bayley M. Effects of lactate ions on the cardiorespiratory system in rainbow trout ( Oncorhynchus mykiss). Am J Physiol Regul Integr Comp Physiol 2019; 316:R607-R620. [PMID: 30811217 DOI: 10.1152/ajpregu.00395.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Lactate ions are involved in several physiological processes, including a direct stimulation of the carotid body, causing increased ventilation in mammals. A similar mechanism eliciting ventilatory stimulation in other vertebrate classes has been demonstrated, but it remains to be thoroughly investigated. Here, we investigated the effects of lactate ions on the cardiorespiratory system in swimming rainbow trout by manipulating the blood lactate concentration. Lactate elicited a vigorous, dose-dependent elevation of ventilation and bradycardia at physiologically relevant concentrations at constant pH. After this initial confirmation, we examined the chiral specificity of the response and found that only l-lactate induced these effects. By removal of the afferent inputs from the first gill arch, the response was greatly attenuated, and a comparison of the responses to injections up- and downstream of the gills collectively demonstrated that the lactate response was initiated by branchial cells. Injection of specific receptor antagonists revealed that a blockade of serotonergic receptors, which are involved in the hypoxic ventilatory response, significantly reduced the lactate response. Finally, we identified two putative lactate receptors based on sequence homology and found that both were expressed at substantially higher levels in the gills. We propose that lactate ions modulate ventilation by stimulating branchial oxygen-sensing cells, thus eliciting a cardiorespiratory response through receptors likely to have originated early in vertebrate evolution.
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Affiliation(s)
- Mikkel T Thomsen
- Department of Bioscience, Zoophysiology, Aarhus University , Aarhus , Denmark
| | - Sjannie Lefevre
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo , Oslo , Norway
| | - Göran E Nilsson
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo , Oslo , Norway
| | - Tobias Wang
- Department of Bioscience, Zoophysiology, Aarhus University , Aarhus , Denmark.,Aarhus Institute of Advanced Studies, Aarhus University , Aarhus , Denmark
| | - Mark Bayley
- Department of Bioscience, Zoophysiology, Aarhus University , Aarhus , Denmark
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20
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Abstract
Respiratory chemoreceptors in vertebrates are specialized cells that detect chemical changes in the environment or arterial blood supply and initiate autonomic responses, such as hyperventilation or changes in heart rate, to improve O2 uptake and delivery to tissues. These chemoreceptors are sensitive to changes in O2, CO2 and/or H+. In fish and mammals, respiratory chemoreceptors may be additionally sensitive to ammonia, hypoglycemia, and numerous other stimuli. Thus, chemoreceptors that affect respiration respond to different types of stimuli (or modalities) and are considered to be "polymodal". This review discusses the polymodal nature of respiratory chemoreceptors in vertebrates with a particular emphasis on chemoreceptors of the carotid body and pulmonary epithelium in mammals, and on neuroepithelial cells in water- and air-breathing fish. A major goal will be to examine the evidence for putative polymodal chemoreceptors in fish within the context of studies on mammalian models, for which polymodal chemoreceptors are well described, in order to improve our understanding of the evolution of polymodal chemoreceptors in vertebrates, and to aid in future studies that aim to identify putative receptors in air- and water-breathing fish.
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21
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Cartolano MC, Amador MHB, Tzaneva V, Milsom WK, McDonald MD. Extrinsic nerves are not involved in branchial 5-HT dynamics or pulsatile urea excretion in Gulf toadfish, Opsanus beta. Comp Biochem Physiol A Mol Integr Physiol 2017; 214:58-65. [PMID: 28887162 DOI: 10.1016/j.cbpa.2017.08.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 08/24/2017] [Accepted: 08/25/2017] [Indexed: 10/18/2022]
Abstract
Gulf toadfish (Opsanus beta) can switch from continuously excreting ammonia as their primary nitrogenous waste to excreting predominantly urea in distinct pulses. Previous studies have shown that the neurotransmitter serotonin (5-HT) is involved in controlling this process, but it is unknown if 5-HT availability is under central nervous control or if the 5-HT signal originates from a peripheral source. Following up on a previous study, cranial nerves IX (glossopharyngeal) and X (vagus) were sectioned to further characterize their role in controlling pulsatile urea excretion and 5-HT release within the gill. In contrast to an earlier study, nerve sectioning did not result in a change in urea pulse frequency. Total urea excretion, average pulse size, total nitrogen excretion, and percent ureotely were reduced the first day post-surgery in nerve-sectioned fish but recovered by 72h post-surgery. Nerve sectioning also had no effect on toadfish urea transporter (tUT), 5-HT transporter (SERT), or 5-HT2A receptor mRNA expression or 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) abundance in the gill, all of which were found consistently across the three gill arches except 5-HIAA, which was undetectable in the first gill arch. Our findings indicate that the central nervous system does not directly control pulsatile urea excretion or local changes in gill 5-HT and 5-HIAA abundance.
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Affiliation(s)
- Maria C Cartolano
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA.
| | - Molly H B Amador
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA
| | - Velislava Tzaneva
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - William K Milsom
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - M Danielle McDonald
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA
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22
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Dang M, Nørregaard R, Bach L, Sonne C, Søndergaard J, Gustavson K, Aastrup P, Nowak B. Metal residues, histopathology and presence of parasites in the liver and gills of fourhorn sculpin (Myoxocephalus quadricornis) and shorthorn sculpin (Myoxocephalus scorpius) near a former lead-zinc mine in East Greenland. ENVIRONMENTAL RESEARCH 2017; 153:171-180. [PMID: 27984761 DOI: 10.1016/j.envres.2016.12.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 12/06/2016] [Accepted: 12/10/2016] [Indexed: 06/06/2023]
Abstract
Fourhorn sculpins (Myoxocephalus quadricornis) and shorthorn sculpins (Myoxocephalus scorpius) have been considered suitable local bioindicators for environmental monitoring studies in the Arctic. Because these species share many characteristics, data from the two species have previously been pooled when assessing marine metal contamination. A chemical and histological study was conducted on fourhorn and shorthorn sculpins collected around a contaminated lead-zinc mine at East Greenland to investigate whether there were any differences in the residues of metals, histopathology and parasites in liver and gills between the two sculpin species. The results demonstrated that concentrations of copper (Cu), zinc (Zn), mercury (Hg) and lead (Pb) were significantly higher in the fourhorn sculpins (p<0.001) while there were no significant differences for arsenic (As) or cadmium (Cd). Furthermore, density of blood vessel fibrosis (p=0.028), prevalence and density of chondroplasia (p=0.002 and p=0.005, respectively), number of mucin-containing mucous cells (p<0.001) and chloride cells (p<0.001) and mean intensity of colonial Peritricha (p<0.001) were significantly higher in fourhorn sculpin. Based on these results we suggest that pooling the two species when conducting environmental assessments is not recommended as it can lead to incorrect conclusions. We propose that a larger study investigating the biological effects of zinc-lead mining in Greenland is needed.
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Affiliation(s)
- Mai Dang
- Institute of Marine and Antarctic Studies University of Tasmania, Launceston, Tasmania 7250, Australia
| | - Rasmus Nørregaard
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Lis Bach
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Christian Sonne
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Jens Søndergaard
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Kim Gustavson
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Peter Aastrup
- Aarhus University, Faculty of Science and Technology, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Barbara Nowak
- Institute of Marine and Antarctic Studies University of Tasmania, Launceston, Tasmania 7250, Australia.
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23
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24
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The role of the autonomic nervous system in control of cardiac and air-breathing responses to sustained aerobic exercise in the African sharptooth catfish Clarias gariepinus. Comp Biochem Physiol A Mol Integr Physiol 2017; 203:273-280. [DOI: 10.1016/j.cbpa.2016.09.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 09/26/2016] [Accepted: 09/27/2016] [Indexed: 01/24/2023]
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25
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Zachar PC, Pan W, Jonz MG. Distribution and morphology of cholinergic cells in the branchial epithelium of zebrafish (Danio rerio). Cell Tissue Res 2016; 367:169-179. [DOI: 10.1007/s00441-016-2531-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 10/25/2016] [Indexed: 10/20/2022]
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26
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Mistri A, Verma N, Kumari U, Mittal S, Mittal AK. Surface ultrastructure of gills in relation to the feeding ecology of an angler catfish Chaca chaca (Siluriformes, Chacidae). Microsc Res Tech 2016; 79:973-981. [PMID: 27465704 DOI: 10.1002/jemt.22729] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 07/11/2016] [Indexed: 11/12/2022]
Abstract
Surface ultrastructure of the gills of the angler catfish Chaca chaca was investigated to unravel the adaptive modifications associated with the feeding ecology of the fish. The fish is often found in mud or in soft substrates where they remain buried both for protection and to feed. Gill rakers present on the gill arch in most fish species are absent in this fish. The absence of gill rakers are associated with the feeding habit of the fish and is considered to facilitate the swallowing of captured prey smoothly without any hindrance. Highly corrugated surface of the gill arch and gill filaments could be associated to retain water/mucus to prevent dessicassion of the fish. Papillae like epithelial protuberances each bearing a taste bud at its summit toward the pharyngeal side of the gill arch is associated with the sorting of the food. Large number of mucous goblet cells on the gill arch epithelium are considered to secret copious mucus to lubricate the prey for easy swallowing. In C. chaca the gill septa between gill filaments are reduced. This could enhance the flexibility and permit the free movement of the gill filaments. Extensive secondary lamellae and infrequent mucous goblet cells on secondary lamellae are associated to increase the surface area to enhance efficiency of gaseous exchange.
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Affiliation(s)
- Arup Mistri
- Skin Physiology Laboratory, Centre of Advanced Study, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India
| | - Neeraj Verma
- Skin Physiology Laboratory, Centre of Advanced Study, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India
| | - Usha Kumari
- Skin Physiology Laboratory, Centre of Advanced Study, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India.,Zoology Section, Mahila Mahavidyalaya, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India
| | - Swati Mittal
- Skin Physiology Laboratory, Centre of Advanced Study, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India.
| | - Ajay Kumar Mittal
- Skin Physiology Laboratory, Centre of Advanced Study, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India
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27
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The sensing of respiratory gases in fish: Mechanisms and signalling pathways. Respir Physiol Neurobiol 2016; 224:71-9. [DOI: 10.1016/j.resp.2015.06.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 06/16/2015] [Accepted: 06/17/2015] [Indexed: 12/29/2022]
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28
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Transcriptome Analysis of Chemically-Induced Sensory Neuron Ablation in Zebrafish. PLoS One 2016; 11:e0148726. [PMID: 26863206 PMCID: PMC4749159 DOI: 10.1371/journal.pone.0148726] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 01/22/2016] [Indexed: 12/31/2022] Open
Abstract
Peripheral glia are known to have a critical role in the initial response to axon damage and degeneration. However, little is known about the cellular responses of non-myelinating glia to nerve injury. In this study, we analyzed the transcriptomes of wild-type and mutant (lacking peripheral glia) zebrafish larvae that were treated with metronidazole. This treatment allowed us to conditionally and selectively ablate cranial sensory neurons whose axons are ensheathed only by non-myelinating glia. While transcripts representing over 27,000 genes were detected by RNAseq, only a small fraction (~1% of genes) were found to be differentially expressed in response to neuronal degeneration in either line at either 2 hrs or 5 hrs of metronidazole treatment. Analysis revealed that most expression changes (332 out of the total of 458 differentially expressed genes) occurred over a continuous period (from 2 to 5 hrs of metronidazole exposure), with a small number of genes showing changes limited to only the 2 hr (55 genes) or 5 hr (71 genes) time points. For genes with continuous alterations in expression, some of the most meaningful sets of enriched categories in the wild-type line were those involving the inflammatory TNF-alpha and IL6 signaling pathways, oxidoreductase activities and response to stress. Intriguingly, these changes were not observed in the mutant line. Indeed, cluster analysis indicated that the effects of metronidazole treatment on gene expression was heavily influenced by the presence or absence of glia, indicating that the peripheral non-myelinating glia play a significant role in the transcriptional response to sensory neuron degeneration. This is the first transcriptome study of metronidazole-induced neuronal death in zebrafish and the response of non-myelinating glia to sensory neuron degeneration. We believe this study provides important insight into the mechanisms by which non-myelinating glia react to neuronal death and degeneration in sensory circuits.
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29
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Sandblom E, Ekström A, Brijs J, Sundström LF, Jutfelt F, Clark TD, Adill A, Aho T, Gräns A. Cardiac reflexes in a warming world: Thermal plasticity of barostatic control and autonomic tones in a temperate fish. J Exp Biol 2016; 219:2880-2887. [DOI: 10.1242/jeb.140319] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 07/04/2016] [Indexed: 12/24/2022]
Abstract
Thermal plasticity of cardiorespiratory function allows ectotherms like fish to cope with seasonal temperature changes and is critical for resilience to climate change. Yet, the chronic thermal effects on cardiovascular homeostatic reflexes in fish are little understood although this may have important implications for physiological performance and overall resilience to climate warming. We compared cardiac autonomic control and baroreflex regulation of heart rate in perch (Perca fluviatilis L.) from a reference area in the Baltic Sea at 18–19°C with conspecifics from the ‘Biotest enclosure’, a chronically heated ecosystem receiving warmed effluent water (24–25°C) from a nuclear power plant. Resting heart rates of Biotest fish displayed clear thermal compensation and were 58.3±2.3 beats min−1 compared with 52.4±2.6 beats min−1 in reference fish at their respective environmental temperatures (Q10: 1.2). The thermally-compensated heart rate of Biotest fish was a combined effect of elevated inhibitory cholinergic tone (105% in Biotest fish versus 70% in reference fish) and reduced intrinsic cardiac pacemaker rate. A barostatic response was evident in both groups, as pharmacologically-induced increases and decreases in blood pressure resulted in atropine-sensitive bradycardia and tachycardia, respectively. Yet, the tachycardia in Biotest fish was significantly greater, presumably due to the larger scope for vagal release. Acclimation of Biotest fish to 18°C for 3 weeks abolished differences in intrinsic heart rate and autonomic tones, suggesting considerable short-term thermal plasticity of cardiovascular control in this species. The heightened hypotensive tachycardia in Biotest perch may represent an important mechanism of ectothermic vertebrates that safeguards tissue perfusion pressure when tissue oxygen demand is elevated by environmental warming.
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Affiliation(s)
- E. Sandblom
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - A. Ekström
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - J. Brijs
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - L. F. Sundström
- Department of Animal Ecology/Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - F. Jutfelt
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - T. D. Clark
- Australian Institute of Marine Science, Townsville, Queensland, Australia (current affiliation: University of Tasmania and CSIRO Agriculture Flagship, Hobart, Tasmania, Australia)
| | - A. Adill
- Institute of Coastal Research, Swedish University of Agricultural Sciences, Öregrund, Sweden
| | - T. Aho
- Institute of Coastal Research, Swedish University of Agricultural Sciences, Öregrund, Sweden
| | - A. Gräns
- Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Skara, Sweden
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30
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Crucke J, Van de Kelft A, Huysseune A. The innervation of the zebrafish pharyngeal jaws and teeth. J Anat 2015; 227:62-71. [PMID: 26018453 DOI: 10.1111/joa.12321] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2015] [Indexed: 12/12/2022] Open
Abstract
Zebrafish (Danio rerio) teeth are increasingly used as a model to study odontogenesis in non-mammalians. Using serial semi-thin section histology and immunohistochemistry, the nerves innervating the pharyngeal jaws and teeth have been identified. The last pair of branchial arches, which are non-gill bearing but which carry the teeth, are innervated by an internal branch of a post-trematic ramus of the vagal nerve. Another, external, branch is probably responsible for the motor innervation of the branchiomeric musculature. Nerve fibres appear in the pulp cavity of the teeth only late during cytodifferentiation, and are therefore likely not involved in early steps of tooth formation. The precise role of the nervous system during continuous tooth replacement remains to be determined. Nonetheless, this study provides the necessary morphological background information to address this question.
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Affiliation(s)
- Jeroen Crucke
- Evolutionary Developmental Biology, Ghent University, Ghent, Belgium
| | | | - Ann Huysseune
- Evolutionary Developmental Biology, Ghent University, Ghent, Belgium
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31
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Tzaneva V, Perry SF. A time differential staining technique coupled with full bilateral gill denervation to study ionocytes in fish. J Vis Exp 2015. [PMID: 25868043 PMCID: PMC4401372 DOI: 10.3791/52548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Branchial ionocytes (ICs) are the functional units for ionic regulation in fish. In adults, they are found on the filamental and lamellar epithelia of the gill where they transport ions such as Na+, Cl- and Ca2+ via a variety of ion channels, pumps and exchangers. The teleost gill is extrinsically innervated by the facial (VI), glossopharyngeal (IX) and vagus (X) nerves. The IX and X nerves are also the extrinsic source of branchial IC innervation. Here, two techniques used to study the innervation, proliferation and distribution of ICs are described: a time differential staining technique and a full bilateral gill denervation technique. Briefly, goldfish are exposed to a vital mitochondrion-specific dye (e.g., MitoTracker Red) which labels (red fluorescence) pre-existing ICs. Fish were either allowed to recover for 3-5 days or immediately underwent a full bilateral gill denervation. After 3-5 days of recovery, the gills are harvested and fixed for immunohistochemistry. The tissue is then stained with an α-5 primary antibody (targets Na+/K+ ATPase containing cells) in conjunction with a secondary antibody that labels all (both new and pre-existing) ICs green. Using confocal imaging, it was demonstrated that pre-existing ICs appear yellow (labelled with both a viable mitochondrion-specific dye and α-5) and new ICs appear green (labelled with α-5 only). Both techniques used in tandem can be applied to study the innervation, proliferation and distribution of ICs on the gill filament when fish are exposed to environmental challenges.
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32
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Elasmobranch Cardiovascular System. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/b978-0-12-801286-4.00001-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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33
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Kermorgant M, Lancien F, Mimassi N, Tyler CR, Le Mével JC. Effects of intracerebroventricular administered fluoxetine on cardio-ventilatory functions in rainbow trout (Oncorhynchus mykiss). Gen Comp Endocrinol 2014; 205:176-84. [PMID: 24681193 DOI: 10.1016/j.ygcen.2014.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 02/28/2014] [Accepted: 03/10/2014] [Indexed: 12/18/2022]
Abstract
Fluoxetine (FLX) is a selective serotonin (5-HT) reuptake inhibitor present in the aquatic environment which is known to bioconcentrate in the brains of exposed fish. FLX acts as a disruptor of various neuroendocrine functions in the brain, but nothing is known about the possible consequence of FLX exposure on the cardio-ventilatory system in fish. Here we undertook to investigate the central actions of FLX on ventilatory and cardiovascular function in unanesthetized rainbow trout (Oncorhynchus mykiss). Intracerebroventricular (ICV) injection of FLX (dosed between 5 and 25 μg) resulted in a significantly elevated total ventilation (VTOT), with a maximum hyperventilation of +176% (at a dose of 25μg) compared with vehicle injected controls. This increase was due to an increase in ventilatory amplitude (VAMP: +126%) with minor effects on ventilatory frequency. The highest dose of FLX (25 μg) produced a significant increase in mean dorsal aortic blood pressure (PDA: +20%) without effects on heart rate (ƒH). In comparison, intra-arterial injections of FLX (500-2,500 μg) had no effect on ventilation but the highest doses increased both PDA and ƒH. The ICV and IA cardio-ventilatory effects of FLX were very similar to those previously observed following injections of 5-HT, indicating that FLX probably acts via stimulating endogenous 5-HT activity through inhibition of 5-HT transporter(s). Our results demonstrate for the first time in fish that FLX administered within the brain exerts potent stimulatory effects on ventilation and blood pressure increase. The doses of FLX given to fish in our study are higher than the brain concentrations of FLX in fish that result from acute exposure to FLX through the water. Nonetheless, our results indicate possible disrupting action of long term exposure to FLX discharged into the environment on central target sites sensitive to 5-HT involved in cardio-ventilatory control.
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Affiliation(s)
- Marc Kermorgant
- Université Européenne de Bretagne, Université de Brest, INSERM U1101, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR ScInBioS, Faculté de Médecine et des Sciences de la Santé, CHU de Brest, 22 Avenue Camille Desmoulins, CS 93837, 29238 Brest Cedex 3, France
| | - Frédéric Lancien
- Université Européenne de Bretagne, Université de Brest, INSERM U1101, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR ScInBioS, Faculté de Médecine et des Sciences de la Santé, CHU de Brest, 22 Avenue Camille Desmoulins, CS 93837, 29238 Brest Cedex 3, France
| | - Nagi Mimassi
- Université Européenne de Bretagne, Université de Brest, INSERM U1101, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR ScInBioS, Faculté de Médecine et des Sciences de la Santé, CHU de Brest, 22 Avenue Camille Desmoulins, CS 93837, 29238 Brest Cedex 3, France
| | | | - Jean-Claude Le Mével
- Université Européenne de Bretagne, Université de Brest, INSERM U1101, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR ScInBioS, Faculté de Médecine et des Sciences de la Santé, CHU de Brest, 22 Avenue Camille Desmoulins, CS 93837, 29238 Brest Cedex 3, France.
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34
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Porteus CS, Abdallah SJ, Pollack J, Kumai Y, Kwong RWM, Yew HM, Milsom WK, Perry SF. The role of hydrogen sulphide in the control of breathing in hypoxic zebrafish (Danio rerio). J Physiol 2014; 592:3075-88. [PMID: 24756639 DOI: 10.1113/jphysiol.2014.271098] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The current study investigated the role of hydrogen sulphide (H2S) in oxygen sensing, intracellular signalling and promotion of ventilatory responses to hypoxia in adult and larval zebrafish (Danio rerio). Both larval and adult zebrafish exhibited a dose-dependent increase in ventilation to sodium sulphide (Na2S), an H2S donor. In vertebrates, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE) are enzymes that catalyse the endogenous production of H2S. In adult zebrafish, inhibition of both CBS and CSE with aminooxyacetate (AOA) and propargyl glycine (PPG) blunted or abolished the hypoxic hyperventilation, and the addition of Na2S to the water partially rescued the effects of inhibiting endogenous H2S production. In zebrafish larvae (4 days post-fertilization), gene knockdown of either CBS or CSE using morpholinos attenuated the hypoxic ventilatory response. Furthermore, the intracellular calcium concentration of isolated neuroepithelial cells (NECs), which are putative oxygen chemoreceptors, increased significantly when these cells were exposed to 50 μm Na2S, supporting a role for H2S in Ca(2+)-evoked neurotransmitter release in these cells. Finally, immunohistochemical labelling showed that NECs dissociated from adult gill contained CBS and CSE, whereas cutaneous NECs in larval zebrafish expressed only CSE. Taken together, these data show that H2S can be produced in the putative oxygen-sensing cells of zebrafish, the NECs, in which it appears to play a pivotal role in promoting the hypoxic ventilatory response.
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Affiliation(s)
- Cosima S Porteus
- Department of Biosciences, University of British Columbia, Vancouver, BC, Canada
| | - Sara J Abdallah
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - Jacob Pollack
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - Yusuke Kumai
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | | | - Hong M Yew
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - William K Milsom
- Department of Biosciences, University of British Columbia, Vancouver, BC, Canada
| | - Steve F Perry
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
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35
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Porteus CS, Wright PA, Milsom WK. Characterisation of putative oxygen chemoreceptors in bowfin (Amia calva). J Exp Biol 2014; 217:1269-77. [DOI: 10.1242/jeb.098467] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Serotonin containing neuroepithelial cells (NECs) are putative oxygen sensing cells found in different locations within the gills of fish. In this study we wished to determine the effect of sustained internal (blood) hypoxaemia versus external (aquatic) hypoxia on the size and density of NECs in the first gill arch of bowfin (Amia calva), a facultative air breather. We identified five different populations of serotonergic NECs in this species (Types I–V) based on location, presence of synaptic vesicles (SV) that stain for the antibody SV2, innervation and labelling with the neural crest marker HNK-1. Cell Types I–III were innervated, and these cells, which participate in central O2 chemoreflexes, were studied further. Although there was no change in the density of any cell type in bowfin after exposure to sustained hypoxia (6.0 kPa for 7 days) without access to air, all three of these cell types increased in size. In contrast, only Type II and III cells increased in size in bowfin exposed to sustained hypoxia with access to air. These data support the suggestion that NECs are putative oxygen-sensing cells, that they occur in several locations, and that Type I cells monitor only hypoxaemia, whereas both other cell types monitor hypoxia and hypoxaemia.
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Affiliation(s)
- Cosima S. Porteus
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Patricia A. Wright
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - William K. Milsom
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
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36
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Tzaneva V, Vadeboncoeur C, Ting J, Perry SF. Effects of hypoxia-induced gill remodelling on the innervation and distribution of ionocytes in the gill of goldfish, Carassius auratus. J Comp Neurol 2014; 522:118-30. [PMID: 23818320 PMCID: PMC4241026 DOI: 10.1002/cne.23392] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Revised: 05/22/2013] [Accepted: 06/12/2013] [Indexed: 12/03/2022]
Abstract
The presence of an interlamellar cell mass (ILCM) on the gills of goldfish acclimated to 7°C leads to preferential distribution of branchial ionocytes to the distal edges of the ILCM, where they are likely to remain in contact with the water and hence remain functional. Upon exposure to hypoxia, the ILCM retracts, and the ionocytes become localized to the lamellar surfaces and on the filament epithelium, owing to their migration and the differentiation of new ionocytes from progenitor cells. Here we demonstrate that the majority of the ionocytes receive neuronal innervation, which led us to assess the consequences of ionocyte migration and differentiation during hypoxic gill remodelling on the pattern and extent of ionocyte neuronal innervation. Normoxic 7°C goldfish (ILCM present) possessed significantly greater numbers of ionocytes/mm2 (951.2 ± 94.3) than their 25°C conspecifics (ILCM absent; 363.1 ± 49.6) but a statistically lower percentage of innervated ionocytes (83.1% ± 1.0% compared with 87.8% ± 1.3%). After 1 week of exposure of goldfish to hypoxia, the pool of branchial ionocytes was composed largely of pre-existing migrating cells (555.6 ± 38.1/mm2) and to a lesser extent newly formed ionocytes (226.7 ± 15.1/mm2). The percentage of new (relative to pre-existing) ionocytes remained relatively constant (at ∼30%) after 1 or 2 weeks of normoxic recovery. After hypoxia, pre-existing ionocytes expressed a greater percentage of innervation than newly formed ionocytes in all treatment groups; however, their percentage innervation steadily decreased over 2 weeks of normoxic recovery.
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Affiliation(s)
- Velislava Tzaneva
- Department of Biology, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
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37
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Kermorgant M, Lancien F, Mimassi N, Le Mével JC. Central ventilatory and cardiovascular actions of serotonin in trout. Respir Physiol Neurobiol 2013; 192:55-65. [PMID: 24325919 DOI: 10.1016/j.resp.2013.12.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 11/20/2013] [Accepted: 12/02/2013] [Indexed: 12/11/2022]
Abstract
This study was undertaken to investigate the central actions of 5-HT on ventilatory and cardiovascular variables in the unanesthetized trout. Compared to vehicle, intracerebroventricular injection (ICV) of 5-HT elevated the total ventilation. This elevation was due to its stimulatory action on ventilatory amplitude. Moreover, 5-HT produced a dose-dependent increase in mean dorsal aortic blood pressure (PDA) without change in heart rate (fH). Methysergide, a 5-HT1/5-HT2 receptor antagonist, reduced the hyperventilatory and hypertensive actions of 5-HT. 8-OH-2-(di-n-propylamino) tetralin, a 5-HT1A receptor agonist, increased PDA while α-methyl-5-HT, a 5-HT2 receptor agonist, elevated all ventilatory variables and increased PDA without changing fH. Intra-arterial injection of 5-HT was without effect on ventilation, but 5-HT initially produced hypotension followed by hypertension. These changes were accompanied by tachycardia. It remains to be determined whether endogenous 5-HT within the brain of trout may act as a potent neuroregulator causing stimulatory effects on cardio-ventilatory functions. In the periphery, 5-HT may act as local modulator involved in vasoregulatory mechanisms.
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Affiliation(s)
- Marc Kermorgant
- Université Européenne de Bretagne, Université de Brest, INSERM U650, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR 148 ScInBioS, Faculté de Médecine et des Sciences de la Santé, 22 avenue Camille Desmoulins, CS 93837, CHU de Brest, 29238 Brest Cedex 3, France
| | - Frédéric Lancien
- Université Européenne de Bretagne, Université de Brest, INSERM U650, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR 148 ScInBioS, Faculté de Médecine et des Sciences de la Santé, 22 avenue Camille Desmoulins, CS 93837, CHU de Brest, 29238 Brest Cedex 3, France
| | - Nagi Mimassi
- Université Européenne de Bretagne, Université de Brest, INSERM U650, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR 148 ScInBioS, Faculté de Médecine et des Sciences de la Santé, 22 avenue Camille Desmoulins, CS 93837, CHU de Brest, 29238 Brest Cedex 3, France
| | - Jean-Claude Le Mével
- Université Européenne de Bretagne, Université de Brest, INSERM U650, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR 148 ScInBioS, Faculté de Médecine et des Sciences de la Santé, 22 avenue Camille Desmoulins, CS 93837, CHU de Brest, 29238 Brest Cedex 3, France.
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38
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Pelster B, Schwerte T. The paracrine role of 5-HT in the control of gill blood flow. Respir Physiol Neurobiol 2012; 184:340-6. [DOI: 10.1016/j.resp.2012.05.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 05/11/2012] [Accepted: 05/14/2012] [Indexed: 10/28/2022]
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39
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Shakarchi K, Zachar PC, Jonz MG. Serotonergic and cholinergic elements of the hypoxic ventilatory response in developing zebrafish. ACTA ACUST UNITED AC 2012; 216:869-80. [PMID: 23155078 DOI: 10.1242/jeb.079657] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The chemosensory roles of gill neuroepithelial cells (NECs) in mediating the hyperventilatory response to hypoxia are not clearly defined in fish. While serotonin (5-HT) is the predominant neurotransmitter in O(2)-sensitive gill NECs, acetylcholine (ACh) plays a more prominent role in O(2) sensing in terrestrial vertebrates. The present study characterized the developmental chronology of potential serotonergic and cholinergic chemosensory pathways of the gill in the model vertebrate, the zebrafish (Danio rerio). In immunolabelled whole gills from larvae, serotonergic NECs were observed in epithelia of the gill filaments and gill arches, while non-serotonergic NECs were found primarily in the gill arches. Acclimation of developing zebrafish to hypoxia (P(O2)=75 mmHg) reduced the number of serotonergic NECs observed at 7 days post-fertilization (d.p.f.), and this effect was absent at 10 d.p.f. In vivo administration of 5-HT mimicked hypoxia by increasing ventilation frequency (f(V)) in early stage (7-10 d.p.f.) and late stage larvae (14-21 d.p.f.), while ACh increased f(V) only in late stage larvae. In time course experiments, application of ketanserin inhibited the hyperventilatory response to acute hypoxia (P(O2)=25 mmHg) at 10 d.p.f., while hexamethonium did not have this effect until 12 d.p.f. Cells immunoreactive for the vesicular acetylcholine transporter (VAChT) began to appear in the gill filaments by 14 d.p.f. Characterization in adult gills revealed that VAChT-positive cells were a separate population of neurosecretory cells of the gill filaments. These studies suggest that serotonergic and cholinergic pathways in the zebrafish gill develop at different times and contribute to the hyperventilatory response to hypoxia.
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Affiliation(s)
- Kamila Shakarchi
- Department of Biology, University of Ottawa, Ottawa, ON, Canada K1N 6N5
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40
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5-Hydroxytryptamine initiates pulsatile urea excretion from perfused gills of the gulf toadfish (Opsanus beta). Comp Biochem Physiol A Mol Integr Physiol 2012; 163:30-7. [DOI: 10.1016/j.cbpa.2012.04.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 04/25/2012] [Accepted: 04/25/2012] [Indexed: 11/22/2022]
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41
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Lefevre S, Wang T, Huong DTT, Phuong NT, Bayley M. Partitioning of oxygen uptake and cost of surfacing during swimming in the air-breathing catfish Pangasianodon hypophthalmus. J Comp Physiol B 2012; 183:215-21. [DOI: 10.1007/s00360-012-0701-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/24/2012] [Accepted: 07/27/2012] [Indexed: 11/25/2022]
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42
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Coccimiglio ML, Jonz MG. Serotonergic neuroepithelial cells of the skin in developing zebrafish: morphology, innervation and oxygen-sensitive properties. ACTA ACUST UNITED AC 2012; 215:3881-94. [PMID: 22855620 DOI: 10.1242/jeb.074575] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In teleost fish, O(2) chemoreceptors of the gills (neuroepithelial cells or NECs) initiate cardiorespiratory reflexes during hypoxia. In developing zebrafish, hyperventilatory and behavioural responses to hypoxia are observed before development of gill NECs, indicating that extrabranchial chemoreceptors mediate these responses in embryos. We have characterised a population of cells of the skin in developing zebrafish that resemble O(2)-chemoreceptive gill NECs. Skin NECs were identified by serotonin immunolabelling and were distributed over the entire skin surface. These cells contained synaptic vesicles and were associated with nerve fibres. Skin NECs were first evident in embryos 24-26 h post-fertilisation (h.p.f.), and embryos developed a behavioural response to hypoxia between 24 and 48 h.p.f. The total number of NECs declined with age from approximately 300 cells per larva at 3 days post-fertilisation (d.p.f.) to ~120 cells at 7 d.p.f., and were rarely observed in adults. Acclimation to hypoxia (30 mmHg) or hyperoxia (300 mmHg) resulted in delayed or accelerated development, respectively, of peak resting ventilatory frequency and produced changes in the ventilatory response to hypoxia. In hypoxia-acclimated larvae, the temporal pattern of skin NECs was altered such that the number of cells did not decrease with age. By contrast, hyperoxia produced a more rapid decline in NEC number. The neurotoxin 6-hydroxydopamine degraded catecholaminergic nerve terminals that made contact with skin NECs and eliminated the hyperventilatory response to hypoxia. These results indicate that skin NECs are sensitive to changes in O(2) and suggest that they may play a role in initiating responses to hypoxia in developing zebrafish.
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43
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Zachar PC, Jonz MG. Neuroepithelial cells of the gill and their role in oxygen sensing. Respir Physiol Neurobiol 2012; 184:301-8. [PMID: 22772312 DOI: 10.1016/j.resp.2012.06.024] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 06/20/2012] [Accepted: 06/21/2012] [Indexed: 01/26/2023]
Abstract
A highly sensitive oxygen (O(2)) sensing mechanism is critical for the survival of all vertebrate species. In fish, this requirement is fullfilled by the neuroepithelial cells (NECs) of the gill. NECs are neurotransmitter-containing chemosensory cells that are diffusely distributed within a thin epithelial layer of the filaments and respiratory lamellae of all gill arches, and are innervated by afferent fibers from the central nervous system. In acute cell culture, NECs respond immediately, and in a dose-dependent manner, to acute changes in O(2) tension. Thus, hypoxic stimulation of gill NECs appears to initiate the production of adaptive, cardiorespiratory reflexes that contribute to the maintenance of O(2) uptake in order to meet metabolic demands. This review covers the current evidence for the status of NECs as the primary peripheral O(2) sensors in fish. We have included an overview of the phylogeny of O(2) sensing structures among vertebrate groups, and morphological and physiological evidence for the importance of NECs in O(2) sensing.
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Affiliation(s)
- Peter C Zachar
- Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
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44
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Zachar PC, Jonz MG. Oxygen Sensitivity of Gill Neuroepithelial Cells in the Anoxia-Tolerant Goldfish. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 758:167-72. [DOI: 10.1007/978-94-007-4584-1_23] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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45
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Le Mével JC, Lancien F, Mimassi N, Conlon JM. Brain neuropeptides in central ventilatory and cardiovascular regulation in trout. Front Endocrinol (Lausanne) 2012; 3:124. [PMID: 23115556 PMCID: PMC3483629 DOI: 10.3389/fendo.2012.00124] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Accepted: 10/01/2012] [Indexed: 12/20/2022] Open
Abstract
Many neuropeptides and their G-protein coupled receptors (GPCRs) are present within the brain area involved in ventilatory and cardiovascular regulation but only a few mammalian studies have focused on the integrative physiological actions of neuropeptides on these vital cardio-respiratory regulations. Because both the central neuroanatomical substrates that govern motor ventilatory and cardiovascular output and the primary sequence of regulatory peptides and their receptors have been mostly conserved through evolution, we have developed a trout model to study the central action of native neuropeptides on cardio-ventilatory regulation. In the present review, we summarize the most recent results obtained using this non-mammalian model with a focus on PACAP, VIP, tachykinins, CRF, urotensin-1, CGRP, angiotensin-related peptides, urotensin-II, NPY, and PYY. We propose hypotheses regarding the physiological relevance of the results obtained.
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Affiliation(s)
- Jean-Claude Le Mével
- INSERM UMR 1101, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR ScInBioS, Faculté de Médecine et des Sciences de la Santé, Université Européenne de Bretagne, Université de Brest, CHU de BrestBrest, France
- *Correspondence: Jean-Claude Le Mével, INSERM UMR 1101, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR ScInBioS, Faculté de Médecine et des Sciences de la Santé, Université Européenne de Bretagne, Université de Brest, CHU de Brest, 22 avenue Camille Desmoulins, CS 93837, 29238 Brest Cedex 3, France. e-mail:
| | - Frédéric Lancien
- INSERM UMR 1101, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR ScInBioS, Faculté de Médecine et des Sciences de la Santé, Université Européenne de Bretagne, Université de Brest, CHU de BrestBrest, France
| | - Nagi Mimassi
- INSERM UMR 1101, Laboratoire de Traitement de l'Information Médicale, Laboratoire de Neurophysiologie, SFR ScInBioS, Faculté de Médecine et des Sciences de la Santé, Université Européenne de Bretagne, Université de Brest, CHU de BrestBrest, France
| | - J. Michael Conlon
- Department of Biochemistry, Faculty of Medicine and Health Sciences, United Arab Emirates UniversityAl Ain, United Arab Emirates
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Autonomic control of circulation in fish: A comparative view. Auton Neurosci 2011; 165:127-39. [DOI: 10.1016/j.autneu.2011.08.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 08/10/2011] [Accepted: 08/11/2011] [Indexed: 11/20/2022]
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47
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Kumari U, Mittal S, Mittal AK. Surface ultrastructure of the gill filaments and the secondary lamellae of the catfish,Rita rita, and the carp, Cirrhinus mrigala. Microsc Res Tech 2011; 75:433-40. [DOI: 10.1002/jemt.21074] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Accepted: 08/01/2011] [Indexed: 11/06/2022]
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48
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Chapman CA, Harahush BK, Renshaw GMC. The physiological tolerance of the grey carpet shark (Chiloscyllium punctatum) and the epaulette shark (Hemiscyllium ocellatum) to anoxic exposure at three seasonal temperatures. FISH PHYSIOLOGY AND BIOCHEMISTRY 2011; 37:387-399. [PMID: 20922566 DOI: 10.1007/s10695-010-9439-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Accepted: 09/15/2010] [Indexed: 05/29/2023]
Abstract
The epaulette shark (Hemiscyllium ocellatum) and the grey carpet shark (Chiloscyllium punctatum) are commonly found in periodically hypoxic environments. The ecophysiological time available for these animals to safely exploit these niches during different seasonal temperatures was examined. The time to loss of righting reflex (T (LRR)) was examined in response to an open ended anoxic challenge at three seasonal temperatures (23, 25 and 27°C). Ventilation rates were measured in an open ended anoxic challenge at 23°C and during 1.5 h of anoxia followed by 2 h of re-oxygenation at 23 and 25°C. The mean T (LRR) of epaulette and grey carpet sharks was inversely proportional to temperature. The T (LRR) was similar between species at 23°C; however, grey carpet sharks had significantly reduced T (LRR) at higher temperatures. During the standardised anoxic challenge, epaulette sharks entered into ventilatory depression significantly earlier at 25°C. During re-oxygenation, epaulette sharks exposed to anoxia at 23°C had no significant increase in ventilation rates. However, after anoxic challenge and re-oxygenation at 25°C, epaulette sharks showed a significant increase in ventilation rates during re-oxygenation. Grey carpet sharks displayed no evidence of ventilatory depression during anoxia. However, during re-oxygenation, grey carpet sharks had significantly elevated ventilation rates above pre-experimental levels and control animals. These data demonstrate that the anoxia tolerance times of both species were temperature dependent, with a significant reduction in the T (LRR) occurring at higher temperatures. Epaulette sharks had a significantly greater T (LRR) at higher temperatures than grey carpet sharks, which did not enter into a ventilatory depression.
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Affiliation(s)
- Clint A Chapman
- UnderWater World, Parkyn Parade, Mooloolaba, Sunshine Coast, QLD 4557, Australia.
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49
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Zakhary SM, Ayubcha D, Ansari F, Kamran K, Karim M, Leheste JR, Horowitz JM, Torres G. A behavioral and molecular analysis of ketamine in zebrafish. Synapse 2011; 65:160-7. [PMID: 20623473 DOI: 10.1002/syn.20830] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Ketamine exerts powerful anesthetic, psychotic, and antidepressant effects in both healthy volunteers and clinically depressed patients. Although ketamine targets particular glutamate receptors, there is a dearth of evidence for additional, alternative molecular substrates for the behavioral actions of this N-methyl-D-aspartate (NMDA) receptor antagonist drug. Here, we provide behavioral and molecular evidence for the actions of ketamine using a new vertebrate model for psychiatric disorders: the zebrafish. Subanesthetic doses of ketamine produced a variety of abnormal behaviors in zebrafish that were qualitatively analogous to those previously measured in humans and rodents treated with drugs that produce transient psychosis. In addition, we revealed that the transcription factor Phox2b is a molecular substrate for the actions of ketamine, particularly during periods of hypoxic stress. Finally, we also show that SIRT1, a histone deacetylase widely recognized for its link to cell survival is also affected by hypoxia crises. These results establish a relevant assay system in which the effects of psychotomimetic drugs can rapidly be assessed, and provide a plausible and novel neuronal mechanism through which ketamine affects critical sensory circuits that monitor breathing behavior.
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Affiliation(s)
- Sherry M Zakhary
- Department of Neuroscience and Histology, New York College of Osteopathic Medicine of New York Institute of Technology, Old Westbury, New York 11568, USA
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50
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Lancien F, Mimassi N, Conlon JM, Le Mével JC. Central pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) decrease the baroreflex sensitivity in trout. Gen Comp Endocrinol 2011; 171:245-51. [PMID: 21320504 DOI: 10.1016/j.ygcen.2011.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Revised: 02/01/2011] [Accepted: 02/09/2011] [Indexed: 10/18/2022]
Abstract
Although PACAP and VIP exert diverse actions on heart and blood vessels along the vertebrate phylum, no information is currently available concerning the potential role of these peptides on the regulation of the baroreflex response, a major mechanism for blood pressure homeostasis. Consequently, the goal of this study was to examine in our experimental model, the unanesthetized rainbow trout Oncorhynchus mykiss, whether PACAP and VIP are involved in the regulation of the cardiac baroreflex sensitivity (BRS). Cross-spectral analysis techniques using a fast Fourier transform algorithm were employed to calculate the coherence, phase and gain of the transfer function between spontaneous fluctuations of systolic arterial blood pressure and R-R intervals of the electrocardiogram. The BRS was estimated as the mean of the gain of the transfer function when the coherence between the two signals was high and the phase negative. Compared with vehicle, intracerebroventricular (i.c.v.) injections of trout PACAP-27 and trout VIP (25-100 pmol) dose-dependently reduced the cardiac BRS to the same extent with a threshold dose of 50 pmol for a significant effect. When injected intra-arterially at the same doses as for i.c.v. injections, only the highest dose of VIP (100 pmol) significantly attenuated the BRS. These results suggest that the endogenous peptides PACAP and VIP might be implicated in the central control of cardiac baroreflex functions in trout.
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Affiliation(s)
- Frédéric Lancien
- Université Européenne de Bretagne, INSERM U650, Laboratoire de Traitement de l'Information Médicale, IFR 148 ScInBioS, Faculté de Médecine et des Sciences de la Santé, 22 Avenue Camille Desmoulins, CS 93837, 29238 Brest Cedex 3, CHU de Brest, France
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