1
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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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2
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Reed M, Pan W, Musa L, Arlotta S, Mennigen JA, Jonz MG. A role for dopamine in control of the hypoxic ventilatory response via D 2 receptors in the zebrafish gill. J Comp Neurol 2024; 532:e25548. [PMID: 37837632 DOI: 10.1002/cne.25548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 09/21/2023] [Accepted: 10/03/2023] [Indexed: 10/16/2023]
Abstract
Dopamine is a neurotransmitter involved in oxygen sensing and control of reflex hyperventilation. In aquatic vertebrates, oxygen sensing occurs in the gills via chemoreceptive neuroepithelial cells (NECs), but a mechanism for dopamine in autonomic control of ventilation has not been defined. We used immunohistochemistry and confocal microscopy to map the distribution of tyrosine hydroxylase (TH), an enzyme necessary for dopamine synthesis, in the gills of zebrafish. TH was found in nerve fibers of the gill filaments and respiratory lamellae. We further identified dopamine active transporter (dat) and vesicular monoamine transporter (vmat2) expression in neurons of the gill filaments using transgenic lines. Moreover, TH- and dat-positive nerve fibers innervated NECs. In chemical screening assays, domperidone, a D2 receptor antagonist, increased ventilation frequency in zebrafish larvae in a dose-dependent manner. When larvae were confronted with acute hypoxia, the D2 agonist, quinpirole, abolished the hyperventilatory response. Quantitative polymerase chain reaction confirmed expression of drd2a and drd2b (genes encoding D2 receptors) in the gills, and their relative abundance decreased following acclimation to hypoxia for 48 h. We localized D2 receptor immunoreactivity to NECs in the efferent gill filament epithelium, and a novel cell type in the afferent filament epithelium. We provide evidence for the synthesis and storage of dopamine by sensory nerve terminals that innervate NECs. We further suggest that D2 receptors on presynaptic NECs provide a feedback mechanism that attenuates the chemoreceptor response to hypoxia. Our studies suggest that a fundamental, modulatory role for dopamine in oxygen sensing arose early in vertebrate evolution.
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Affiliation(s)
- Maddison Reed
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Wen Pan
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Lina Musa
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Stefania Arlotta
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Jan A Mennigen
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Michael G Jonz
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
- Brain and Mind Research Institute, University of Ottawa, Ottawa, Ontario, Canada
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3
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Perry SF, Pan YK, Gilmour KM. Insights into the control and consequences of breathing adjustments in fishes-from larvae to adults. Front Physiol 2023; 14:1065573. [PMID: 36793421 PMCID: PMC9923008 DOI: 10.3389/fphys.2023.1065573] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 01/11/2023] [Indexed: 01/31/2023] Open
Abstract
Adjustments of ventilation in fishes to regulate the volume of water flowing over the gills are critically important responses to match branchial gas transfer with metabolic needs and to defend homeostasis during environmental fluctuations in O2 and/or CO2 levels. In this focused review, we discuss the control and consequences of ventilatory adjustments in fish, briefly summarizing ventilatory responses to hypoxia and hypercapnia before describing the current state of knowledge of the chemoreceptor cells and molecular mechanisms involved in sensing O2 and CO2. We emphasize, where possible, insights gained from studies on early developmental stages. In particular, zebrafish (Danio rerio) larvae have emerged as an important model for investigating the molecular mechanisms of O2 and CO2 chemosensing as well as the central integration of chemosensory information. Their value stems, in part, from their amenability to genetic manipulation, which enables the creation of loss-of-function mutants, optogenetic manipulation, and the production of transgenic fish with specific genes linked to fluorescent reporters or biosensors.
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4
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Reed M, Jonz MG. Neurochemical Signalling Associated With Gill Oxygen Sensing and Ventilation: A Receptor Focused Mini-Review. Front Physiol 2022; 13:940020. [PMID: 35910553 PMCID: PMC9325958 DOI: 10.3389/fphys.2022.940020] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 06/21/2022] [Indexed: 11/13/2022] Open
Abstract
Despite the large body of work describing vertebrate ventilatory responses to hypoxia, remarkably little is known about the receptors and afferent pathways mediating these responses in fishes. In this review, we aim to summarize all receptor types to date implicated in the neurotransmission or neuromodulation associated with O2 sensing in the gills of fish. This includes serotonergic, cholinergic, purinergic, and dopaminergic receptor subtypes. Recent transcriptomic analysis of the gills of zebrafish using single-cell RNA sequencing has begun to elucidate specific receptor targets in the gill; however, the absence of receptor characterization at the cellular level in the gill remains a major limitation in understanding the neurochemical control of hypoxia signalling.
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Affiliation(s)
- Maddison Reed
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - Michael G. Jonz
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
- Brain and Mind Research Institute, University of Ottawa, ON, Ottawa, Canada
- *Correspondence: Michael G. Jonz,
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5
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Fu CW, Horng JL, Chou MY. Fish Behavior as a Neural Proxy to Reveal Physiological States. Front Physiol 2022; 13:937432. [PMID: 35910555 PMCID: PMC9326089 DOI: 10.3389/fphys.2022.937432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 06/23/2022] [Indexed: 11/13/2022] Open
Abstract
Behaviors are the integrative outcomes of the nervous system, which senses and responds to the internal physiological status and external stimuli. Teleosts are aquatic organisms which are more easily affected by the surrounding environment compared to terrestrial animals. To date, behavioral tests have been widely used to assess potential environmental risks using fish as model animals. In this review, we summarized recent studies regarding the effects of internal and external stimuli on fish behaviors. We concluded that behaviors reflect environmental and physiological changes, which have possible implications for environmental and physiological assessments.
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Affiliation(s)
- Chih-Wei Fu
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Jiun-Lin Horng
- Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ming-Yi Chou
- Department of Life Science, National Taiwan University, Taipei, Taiwan
- *Correspondence: Ming-Yi Chou,
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6
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Single-cell transcriptomic analysis of neuroepithelial cells and other cell types of the gills of zebrafish (Danio rerio) exposed to hypoxia. Sci Rep 2022; 12:10144. [PMID: 35710785 PMCID: PMC9203529 DOI: 10.1038/s41598-022-13693-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 05/26/2022] [Indexed: 12/21/2022] Open
Abstract
The fish gill is a multifunctional organ involved in numerous physiological processes, such as gas exchange and sensing of hypoxia by respiratory chemoreceptors, called neuroepithelial cells (NECs). Many studies have focused on zebrafish (Danio rerio) to investigate the structure, function and development of the gills, yet the transcriptomic profile of most gill cells remains obscure. We present the results of a comprehensive transcriptomic analysis of the gills of zebrafish using single-cell RNA sequencing (scRNA‐seq). Gill cells from ETvmat2:EGFP zebrafish were individually labelled before scRNA‐seq library construction using 10× Genomics Chromium technology. 12,819 cells were sequenced with an average depth of over 27,000 reads per cell. We identified a median of 485 genes per cell and 16 cell clusters, including NECs, neurons, pavement cells, endothelial cells and mitochondrion-rich cells. The identity of NECs was confirmed by expression of slc18a2, encoding the vesicular monoamine transporter, Vmat2. Highly differentially-expressed genes in NECs included tph1a, encoding tryptophan hydroxylase, sv2 (synaptic vesicle protein), and proteins implicated in O2 sensing (ndufa4l2a, cox8al and epas1a). In addition, NECs and neurons expressed genes encoding transmembrane receptors for serotonergic, cholinergic or dopaminergic neurotransmission. Differential expression analysis showed a clear shift in the transcriptome of NECs following 14 days of acclimation to hypoxia. NECs in the hypoxia group showed high expression of genes involved in cell cycle control and proliferation. The present article provides a complete cell atlas for the zebrafish gill and serves as a platform for future studies investigating the molecular biology and physiology of this organ.
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Cochrane PV, Jonz MG, Wright PA. The development of the O 2-sensing system in an amphibious fish: consequences of variation in environmental O 2 levels. J Comp Physiol B 2021; 191:681-699. [PMID: 34023926 DOI: 10.1007/s00360-021-01379-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/04/2021] [Accepted: 05/07/2021] [Indexed: 11/25/2022]
Abstract
Proper development of the O2-sensing system is essential for survival. Here, we characterized the development of the O2-sensing system in the mangrove rivulus (Kryptolebias marmoratus), an amphibious fish that transitions between hypoxic aquatic environments and O2-rich terrestrial environments. We found that NECs formed in the gills and skin of K. marmoratus during embryonic development and that both NEC populations are retained from the embryonic stage to adulthood. We also found that the hyperventilatory response to acute hypoxia was present in embryonic K. marmoratus, indicating that functional O2-sensing pathways are formed during embryonic development. We then exposed embryos to aquatic normoxia, aquatic hyperoxia, aquatic hypoxia, or terrestrial conditions for the first 30 days of embryonic development and tested the hypothesis that environmental O2 availability during embryonic development modulates the development of the O2-sensing system in amphibious fishes. Surprisingly, we found that O2 availability during embryonic development had little impact on the density and morphology of NECs in the gills and skin of K. marmoratus. Collectively, our results demonstrate that, unlike the only other species of fish in which NEC development has been studied to date (i.e., zebrafish), NEC development in K. marmoratus is largely unaffected by environmental O2 levels during the embryonic stage, indicating that there is interspecies variation in O2-induced plasticity in the O2-sensing system of fishes.
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Affiliation(s)
- Paige V Cochrane
- Department of Integrative Biology, University of Guelph, Guelph, ON, N1G 2W1, Canada.
| | - Michael G Jonz
- Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Patricia A Wright
- Department of Integrative Biology, University of Guelph, Guelph, ON, N1G 2W1, Canada
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8
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Disruption of tph1 genes demonstrates the importance of serotonin in regulating ventilation in larval zebrafish (Danio rerio). Respir Physiol Neurobiol 2020; 285:103594. [PMID: 33271304 DOI: 10.1016/j.resp.2020.103594] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/13/2020] [Accepted: 11/23/2020] [Indexed: 01/22/2023]
Abstract
Serotonergic neuroepithelial cells (NECs) in larval zebrafish are believed to be O2 chemoreceptors. Serotonin (5-HT) within these NECs has been implicated as a neurotransmitter mediating the hypoxic ventilatory response (HVR). Here, we use knockout approaches to discern the role of 5-HT in regulating the HVR by targeting the rate limiting enzyme for 5-HT synthesis, tryptophan hydroxylase (Tph). Using transgenic lines, we determined that Tph1a is expressed in skin and pharyngeal arch NECs, as well as in pharyngeal arch Merkel-like cells (MLCs), whereas Tph1b is expressed predominately in MLCs. Knocking out the two tph1 paralogs resulted in similar changes in detectable serotonergic cell density between the two mutants, yet their responses to hypoxia (35 mmHg) were different. Larvae lacking Tph1a (tph1a-/- mutants) displayed a higher ventilation rate when exposed to hypoxia compared to wild-types, whereas tph1b-/- mutants exhibited a lower ventilation rate suggesting that 5-HT located in locations other than NECs, may play a dominant role in regulating the HVR.
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9
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Koudrina N, Perry SF, Gilmour KM. The role of TASK-2 channels in CO 2 sensing in zebrafish ( Danio rerio). Am J Physiol Regul Integr Comp Physiol 2020; 319:R329-R342. [PMID: 32697653 DOI: 10.1152/ajpregu.00132.2020] [Citation(s) in RCA: 4] [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
Peripheral chemosensitivity in fishes is thought to be mediated by serotonin-enriched neuroepithelial cells (NECs) that are localized to the gills of adults and the integument of larvae. In adult zebrafish (Danio rerio), branchial NECs are presumed to mediate the cardiorespiratory reflexes associated with hypoxia or hypercapnia, whereas in larvae, there is indirect evidence linking cutaneous NECs to hypoxic hyperventilation and hypercapnic tachycardia. No study yet has examined the ventilatory response of larval zebrafish to hypercapnia, and regardless of developmental stage, the signaling pathways involved in CO2 sensing remain unclear. In the mouse, a background potassium channel (TASK-2) contributes to the sensitivity of chemoreceptor cells to CO2. Zebrafish possess two TASK-2 channel paralogs, TASK-2 and TASK-2b, encoded by kcnk5a and kcnk5b, respectively. The present study aimed to determine whether TASK-2 channels are expressed in NECs of larval zebrafish and whether they are involved in CO2 sensing. Using immunohistochemical approaches, TASK-2 protein was observed on the surface of NECs in larvae. Exposure of larvae to hypercapnia caused cardiac and breathing frequencies to increase, and these responses were blunted in fish experiencing TASK-2 and/or TASK-2b knockdown. The results of these experiments suggest that TASK-2 channels are involved in CO2 sensing by NECs and contribute to the initiation of reflex cardiorespiratory responses during exposure of larvae to hypercapnia.
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Affiliation(s)
- N Koudrina
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - S F Perry
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - K M Gilmour
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
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10
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Rossi GS, Cochrane PV, Wright PA. Fluctuating environments during early development can limit adult phenotypic flexibility: insights from an amphibious fish. J Exp Biol 2020; 223:jeb228304. [PMID: 32616545 DOI: 10.1242/jeb.228304] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/29/2020] [Indexed: 12/11/2022]
Abstract
The interaction between developmental plasticity and the capacity for reversible acclimation (phenotypic flexibility) is poorly understood, particularly in organisms exposed to fluctuating environments. We used an amphibious killifish (Kryptolebias marmoratus) to test the hypotheses that organisms reared in fluctuating environments (i) will make no developmental changes to suit any one environment because fixing traits to suit one environment could be maladaptive for another, and (ii) will be highly phenotypically flexible as adults because their early life experiences predict high environmental variability in the future. We reared fish under constant (water) or fluctuating (water-air) environments until adulthood and assessed a suite of traits along the oxygen cascade (e.g. neuroepithelial cell density and size, cutaneous capillarity, gill morphology, ventricle size, red muscle morphometrics, terrestrial locomotor performance). To evaluate the capacity for phenotypic flexibility, a subset of adult fish from each rearing condition was then air-exposed for 14 days before the same traits were measured. In support of the developmental plasticity hypothesis, traits involved with O2 sensing and uptake were largely unaffected by water-air fluctuations during early life, but we found marked developmental changes in traits related to O2 transport, utilization and locomotor performance. In contrast, we found no evidence supporting the phenotypic flexibility hypothesis. Adult fish from both rearing conditions exhibited the same degree of phenotypic flexibility in various O2 sensing- and uptake-related traits. In other cases, water-air fluctuations attenuated adult phenotypic flexibility despite the fact that phenotypic flexibility is hypothesized to be favoured when environments fluctuate. Overall, we conclude that exposure to environmental fluctuations during development in K. marmoratus can dramatically alter the constitutive adult phenotype, as well as diminish the scope for phenotypic flexibility in later life.
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Affiliation(s)
- Giulia S Rossi
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1
| | - Paige V Cochrane
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1
| | - Patricia A Wright
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1
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11
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Pan YK, Perry SF. Neuroendocrine control of breathing in fish. Mol Cell Endocrinol 2020; 509:110800. [PMID: 32240728 DOI: 10.1016/j.mce.2020.110800] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/21/2020] [Accepted: 03/23/2020] [Indexed: 10/24/2022]
Abstract
Beginning with the discovery more than 35 years ago that oxygen chemoreceptors of the fish gill are enriched with serotonin, numerous studies have examined the importance of this, and other neuroendocrine factors in piscine chemoreceptor function, and in particular on the chemoreceptor-mediated reflex control of breathing. However, despite these studies, there is continued debate as to the role of neuroendocrine factors in the initiation or modulation of breathing during environmental disturbances or physical activity. In this review, we summarize the state-of-knowledge surrounding the neuroendocrine control of oxygen chemoreception in fish and the associated reflex adjustments to ventilation. We focus on neurohumoral substances that either are present in chemosensory cells or those that are localised elsewhere but have also been implicated in the direct control of breathing. These substances include serotonin, catecholamines (adrenaline and noradrenaline), acetylcholine, purines and gaseous neurotransmitters. Despite the growing indirect evidence for an involvement of these neuroendocrine factors in chemoreception and ventilatory control, direct evidence awaits the incorporation of novel methods currently under development.
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Affiliation(s)
- Yihang Kevin Pan
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada
| | - Steve F Perry
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada.
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12
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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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13
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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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14
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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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15
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Purinergic and adenosine receptors contribute to hypoxic hyperventilation in zebrafish (Danio rerio). Comp Biochem Physiol A Mol Integr Physiol 2017; 214:50-57. [DOI: 10.1016/j.cbpa.2017.09.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 09/15/2017] [Accepted: 09/15/2017] [Indexed: 11/22/2022]
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16
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Stoyek MR, Jonz MG, Smith FM, Croll RP. Distribution and chronotropic effects of serotonin in the zebrafish heart. Auton Neurosci 2017; 206:43-50. [DOI: 10.1016/j.autneu.2017.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 05/03/2017] [Accepted: 07/17/2017] [Indexed: 01/23/2023]
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17
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Zaccone G, Lauriano ER, Kuciel M, Capillo G, Pergolizzi S, Alesci A, Ishimatsu A, Ip YK, Icardo JM. Identification and distribution of neuronal nitric oxide synthase and neurochemical markers in the neuroepithelial cells of the gill and the skin in the giant mudskipper, Periophthalmodon schlosseri. ZOOLOGY 2017; 125:41-52. [PMID: 28830730 DOI: 10.1016/j.zool.2017.08.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 08/02/2017] [Accepted: 08/02/2017] [Indexed: 12/12/2022]
Abstract
Mudskippers are amphibious fishes living in mudflats and mangroves. These fishes hold air in their large buccopharyngeal-opercular cavities where respiratory gas exchange takes place via the gills and higher vascularized epithelium lining the cavities and also the skin epidermis. Although aerial ventilation response to changes in ambient gas concentration has been studied in mudskippers, the localization and distribution of respiratory chemoreceptors, their neurochemical coding and function as well as physiological evidence for the gill or skin as site for O2 and CO2 sensing are currently not known. In the present study we assessed the distribution of serotonin, acetylcholine, catecholamines and nitric oxide in the neuroepithelial cells (NECs) of the mudskipper gill and skin epithelium using immunohistochemistry and confocal microscopy. Colocalization studies showed that 5-HT is coexpressed with nNOS, Na+/K+-ATPase, TH and VAChT; nNOS is coexpressed with Na+/K+-ATPase and TH in the skin. In the gill 5-HT is coexpressed with nNOS and VAhHT and nNOS is coexpressed with Na+/K+-ATPase and TH. Acetylcholine is also expressed in chain and proximal neurons projecting to the efferent filament artery and branchial smooth muscle. The serotonergic cells c labeled with VAChT, nNOS and TH, thus indicating the presence of NEC populations and the possibility that these neurotransmitters (other than serotonin) may act as primary transmitters in the hypoxic reflex in fish gills. Immunolabeling with TH antibodies revealed that NECs in the gill and the skin are innervated by catecholaminergic nerves, thus suggesting that these cells are involved in a central control of branchial functions through their relationships with the sympathetic branchial nervous system. The Na+/K+-ATPase in mitochondria-rich cells (MRCs), which are most concentrated in the gill lamellar epithelium, is colabeled with nNOS and associated with TH nerve terminals. TH-immunopositive fine varicosities were also associated with the numerous capillaries in the skin surface and the layers of the swollen cells. Based on the often hypercapnic and hypoxic habitat of the mudskippers, these fishes may represent an attractive model for pursuing studies on O2 and CO2 sensing due to the air-breathing that increases the importance of acid/base regulation and the O2-related drive including the function of gasotransmitters such as nitric oxide that has an inhibitory (regulatory) function in ionoregulation.
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Affiliation(s)
- Giacomo Zaccone
- Department of Biomedical and Dental Sciences and Department of Morphofunctional Imaging, University of Messina, Polo Universitario dell'Annunziata, 98168 Messina, Italy.
| | - Eugenia Rita Lauriano
- Department of Environmental Sciences, Territorial, Food and Health Security (S.A.S.T.A.S.), University of Messina, Viale Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Michał Kuciel
- Poison Information Centre, Department of Toxicology and Environmental Disease, Jagiellonian University Medical Collage, Kopernika 15, 31-501 Krakow, Poland.
| | - Gioele Capillo
- Department of Environmental Sciences, Territorial, Food and Health Security (S.A.S.T.A.S.), University of Messina, Viale Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Simona Pergolizzi
- Department of Environmental Sciences, Territorial, Food and Health Security (S.A.S.T.A.S.), University of Messina, Viale Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Alessio Alesci
- Department of Environmental Sciences, Territorial, Food and Health Security (S.A.S.T.A.S.), University of Messina, Viale Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Atsushi Ishimatsu
- Institute for East China Sea Research, Nagasaki University, 1551-7 Tairamachi, Nagasaki 851-2213, Japan
| | - Yuen Kwong Ip
- Department of Biological Science, National University of Singapore, 14 Science Drive 4, Singapore 117543, Singapore
| | - Jose M Icardo
- Department of Anatomy and Cell Biology, Polígono de Cazoña, University of Cantabria, 39011 Santander, Spain
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18
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Dean BW, Rashid TJ, Jonz MG. Mitogenic action of hypoxia upon cutaneous neuroepithelial cells in developing zebrafish. Dev Neurobiol 2017; 77:789-801. [DOI: 10.1002/dneu.22471] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 11/14/2016] [Accepted: 11/22/2016] [Indexed: 01/21/2023]
Affiliation(s)
- Benjamin W. Dean
- Department of Biology; University of Ottawa; Ontario K1N 6N5 Canada
| | - Thalia J. Rashid
- Department of Biology; University of Ottawa; Ontario K1N 6N5 Canada
| | - Michael G. Jonz
- Department of Biology; University of Ottawa; Ontario K1N 6N5 Canada
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19
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David A, Lange A, Abdul-Sada A, Tyler CR, Hill EM. Disruption of the Prostaglandin Metabolome and Characterization of the Pharmaceutical Exposome in Fish Exposed to Wastewater Treatment Works Effluent As Revealed by Nanoflow-Nanospray Mass Spectrometry-Based Metabolomics. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:616-624. [PMID: 27976870 DOI: 10.1021/acs.est.6b04365] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Fish can be exposed to a complex mixture of chemical contaminants, including pharmaceuticals, present in discharges of wastewater treatment works (WwTWs) effluents. There is little information on the effects of effluent exposure on fish metabolism, especially the small molecule signaling compounds which are the biological target of many pharmaceuticals. We applied a newly developed sensitive nanoflow-nanospray mass spectrometry nontargeted profiling technique to identify changes in the exposome and metabolome of roach (Rutilus rutilus) exposed to a final WwTWs effluent for 15 days. Effluent exposure resulted in widespread reduction (between 50% and 90%) in prostaglandin (PG) profiles in fish tissues and plasma with disruptions also in tryptophan/serotonin, bile acid and lipid metabolism. Metabolite disruptions were not explained by altered expression of genes associated with the PG or tryptophan metabolism. Of the 31 pharmaceutical metabolites that were detected in the effluent exposome of fish, 6 were nonsteroidal anti-inflammatory drugs but with plasma concentrations too low to disrupt PG biosynthesis. PGs, bile acids, and tryptophan metabolites are important mediators regulating a diverse array of physiological systems in fish and the identity of wastewater contaminants disrupting their metabolism warrants further investigation on their exposure effects on fish health.
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Affiliation(s)
- Arthur David
- School of Life Sciences. University of Sussex . Brighton. U.K. BN1 9QG
| | - Anke Lange
- Biosciences, College of Life & Environmental Sciences. University of Exeter , Exeter. U.K. EX4 4QD
| | - Alaa Abdul-Sada
- School of Life Sciences. University of Sussex . Brighton. U.K. BN1 9QG
| | - Charles R Tyler
- Biosciences, College of Life & Environmental Sciences. University of Exeter , Exeter. U.K. EX4 4QD
| | - Elizabeth M Hill
- School of Life Sciences. University of Sussex . Brighton. U.K. BN1 9QG
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20
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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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21
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Burggren WW, Bautista GM, Coop SC, Couturier GM, Delgadillo SP, García RM, González CAA. Developmental cardiorespiratory physiology of the air-breathing tropical gar, Atractosteus tropicus. Am J Physiol Regul Integr Comp Physiol 2016; 311:R689-R701. [PMID: 27465731 DOI: 10.1152/ajpregu.00022.2016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 07/08/2016] [Indexed: 12/18/2022]
Abstract
The physiological transition to aerial breathing in larval air-breathing fishes is poorly understood. We investigated gill ventilation frequency (fG), heart rate (fH), and air breathing frequency (fAB) as a function of development, activity, hypoxia, and temperature in embryos/larvae from day (D) 2.5 to D30 posthatch of the tropical gar, Atractosteus tropicus, an obligate air breather. Gill ventilation at 28°C began at approximately D2, peaking at ∼75 beats/min on D5, before declining to ∼55 beats/min at D30. Heart beat began ∼36-48 h postfertilization and ∼1 day before hatching. fH peaked between D3 and D10 at ∼140 beats/min, remaining at this level through D30. Air breathing started very early at D2.5 to D3.5 at 1-2 breaths/h, increasing to ∼30 breaths/h at D15 and D30. Forced activity at all stages resulted in a rapid but brief increase in both fG and fH, (but not fAB), indicating that even in these early larval stages, reflex control existed over both ventilation and circulation prior to its increasing importance in older fishes. Acute progressive hypoxia increased fG in D2.5-D10 larvae, but decreased fG in older larvae (≥D15), possibly to prevent branchial O2 loss into surrounding water. Temperature sensitivity of fG and fH measured at 20°C, 25°C, 28°C and 38°C was largely independent of development, with a Q10 between 20°C and 38°C of ∼2.4 and ∼1.5 for fG and fH, respectively. The rapid onset of air breathing, coupled with both respiratory and cardiovascular reflexes as early as D2.5, indicates that larval A. tropicus develops "in the fast lane."
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Affiliation(s)
- Warren W Burggren
- Developmental Integrative Biology Group, Department of Biology, University of North Texas, Denton, Texas; and
| | - Gil Martinez Bautista
- Laboratorio de Acuicultura Tropical, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Villahermosa, Tabasco, Mexico
| | - Susana Camarillo Coop
- Laboratorio de Acuicultura Tropical, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Villahermosa, Tabasco, Mexico
| | - Gabriel Márquez Couturier
- Laboratorio de Acuicultura Tropical, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Villahermosa, Tabasco, Mexico
| | - Salomón Páramo Delgadillo
- Laboratorio de Acuicultura Tropical, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Villahermosa, Tabasco, Mexico
| | - Rafael Martínez García
- Laboratorio de Acuicultura Tropical, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Villahermosa, Tabasco, Mexico
| | - Carlos Alfonso Alvarez González
- Laboratorio de Acuicultura Tropical, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Villahermosa, Tabasco, Mexico
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22
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Rahbar S, Pan W, Jonz MG. Purinergic and Cholinergic Drugs Mediate Hyperventilation in Zebrafish: Evidence from a Novel Chemical Screen. PLoS One 2016; 11:e0154261. [PMID: 27100625 PMCID: PMC4839714 DOI: 10.1371/journal.pone.0154261] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 04/10/2016] [Indexed: 12/29/2022] Open
Abstract
A rapid test to identify drugs that affect autonomic responses to hypoxia holds therapeutic and ecologic value. The zebrafish (Danio rerio) is a convenient animal model for investigating peripheral O2 chemoreceptors and respiratory reflexes in vertebrates; however, the neurotransmitters and receptors involved in this process are not adequately defined. The goals of the present study were to demonstrate purinergic and cholinergic control of the hyperventilatory response to hypoxia in zebrafish, and to develop a procedure for screening of neurochemicals that affect respiration. Zebrafish larvae were screened in multi-well plates for sensitivity to the cholinergic receptor agonist, nicotine, and antagonist, atropine; and to the purinergic receptor antagonists, suramin and A-317491. Nicotine increased ventilation frequency (fV) maximally at 100 μM (EC50 = 24.5 μM). Hypoxia elevated fV from 93.8 to 145.3 breaths min-1. Atropine reduced the hypoxic response only at 100 μM. Suramin and A-317491 maximally reduced fV at 50 μM (EC50 = 30.4 and 10.8 μM) and abolished the hyperventilatory response to hypoxia. Purinergic P2X3 receptors were identified in neurons and O2-chemosensory neuroepithelial cells of the gills using immunohistochemistry and confocal microscopy. These studies suggest a role for purinergic and nicotinic receptors in O2 sensing in fish and implicate ATP and acetylcholine in excitatory neurotransmission, as in the mammalian carotid body. We demonstrate a rapid approach for screening neuroactive chemicals in zebrafish with implications for respiratory medicine and carotid body disease in humans; as well as for preservation of aquatic ecosystems.
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Affiliation(s)
- Saman Rahbar
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Wen Pan
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Michael G. Jonz
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
- * E-mail:
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23
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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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24
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Jonz MG, Zachar PC, Da Fonte DF, Mierzwa AS. Peripheral chemoreceptors in fish: A brief history and a look ahead. Comp Biochem Physiol A Mol Integr Physiol 2015; 186:27-38. [DOI: 10.1016/j.cbpa.2014.09.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 09/03/2014] [Accepted: 09/03/2014] [Indexed: 11/24/2022]
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25
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Radev Z, Hermel JM, Elipot Y, Bretaud S, Arnould S, Duchateau P, Ruggiero F, Joly JS, Sohm F. A TALEN-Exon Skipping Design for a Bethlem Myopathy Model in Zebrafish. PLoS One 2015. [PMID: 26221953 PMCID: PMC4519248 DOI: 10.1371/journal.pone.0133986] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Presently, human collagen VI-related diseases such as Ullrich congenital muscular dystrophy (UCMD) and Bethlem myopathy (BM) remain incurable, emphasizing the need to unravel their etiology and improve their treatments. In UCMD, symptom onset occurs early, and both diseases aggravate with ageing. In zebrafish fry, morpholinos reproduced early UCMD and BM symptoms but did not allow to study the late phenotype. Here, we produced the first zebrafish line with the human mutation frequently found in collagen VI-related disorders such as UCMD and BM. We used a transcription activator-like effector nuclease (TALEN) to design the col6a1ama605003-line with a mutation within an essential splice donor site, in intron 14 of the col6a1 gene, which provoke an in-frame skipping of exon 14 in the processed mRNA. This mutation at a splice donor site is the first example of a template-independent modification of splicing induced in zebrafish using a targetable nuclease. This technique is readily expandable to other organisms and can be instrumental in other disease studies. Histological and ultrastructural analyzes of homozygous and heterozygous mutant fry and 3 months post-fertilization (mpf) fish revealed co-dominantly inherited abnormal myofibers with disorganized myofibrils, enlarged sarcoplasmic reticulum, altered mitochondria and misaligned sarcomeres. Locomotion analyzes showed hypoxia-response behavior in 9 mpf col6a1 mutant unseen in 3 mpf fish. These symptoms worsened with ageing as described in patients with collagen VI deficiency. Thus, the col6a1ama605003-line is the first adult zebrafish model of collagen VI-related diseases; it will be instrumental both for basic research and drug discovery assays focusing on this type of disorders.
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Affiliation(s)
- Zlatko Radev
- UMS 1374, AMAGEN, INRA, Jouy en Josas, Domaine de Vilvert, France
- UMS 3504, AMAGEN, CNRS, Gif-sur-Yvette, France
| | - Jean-Michel Hermel
- UMR 9197, INRA-CASBAH team, NEURO-Psi, CNRS, Gif sur Yvette, France
- * E-mail: (FS); (JMH)
| | - Yannick Elipot
- UMR 9197, DECA team, NEURO-Psi, CNRS, Gif sur Yvette, France
| | - Sandrine Bretaud
- UMR 5242, Institut de Génomique Fonctionnelle de Lyon, ENS de Lyon, CNRS, Université Lyon 1, Lyon, France
| | | | | | - Florence Ruggiero
- UMR 5242, Institut de Génomique Fonctionnelle de Lyon, ENS de Lyon, CNRS, Université Lyon 1, Lyon, France
| | | | - Frédéric Sohm
- UMS 1374, AMAGEN, INRA, Jouy en Josas, Domaine de Vilvert, France
- UMS 3504, AMAGEN, CNRS, Gif-sur-Yvette, France
- * E-mail: (FS); (JMH)
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26
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Jonz MG, Buck LT, Perry SF, Schwerte T, Zaccone G. Sensing and surviving hypoxia in vertebrates. Ann N Y Acad Sci 2015; 1365:43-58. [PMID: 25959851 DOI: 10.1111/nyas.12780] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 03/26/2015] [Accepted: 03/31/2015] [Indexed: 12/15/2022]
Abstract
Surviving hypoxia is one of the most critical challenges faced by vertebrates. Most species have adapted to changing levels of oxygen in their environment with specialized organs that sense hypoxia, while only few have been uniquely adapted to survive prolonged periods of anoxia. The goal of this review is to present the most recent research on oxygen sensing, adaptation to hypoxia, and mechanisms of anoxia tolerance in nonmammalian vertebrates. We discuss the respiratory structures in fish, including the skin, gills, and air-breathing organs, and recent evidence for chemosensory neuroepithelial cells (NECs) in these tissues that initiate reflex responses to hypoxia. The use of the zebrafish as a genetic and developmental model has allowed observation of the ontogenesis of respiratory and chemosensory systems, demonstration of a putative intracellular O2 sensor in chemoreceptors that may initiate transduction of the hypoxia signal, and investigation into the effects of extreme hypoxia on cardiorespiratory development. Other organisms, such as goldfish and freshwater turtles, display a high degree of anoxia tolerance, and these models are revealing important adaptations at the cellular level, such as the regulation of glutamatergic and GABAergic neurotransmission in defense of homeostasis in central neurons.
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Affiliation(s)
- Michael G Jonz
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Leslie T Buck
- Cell and Systems Biology, and Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | - Steve F Perry
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | | | - Giacomo Zaccone
- Department of Environmental Sciences, Territorial, Food and Health Security (S.A.S.T.A.S.), University of Messina, Messina, Italy
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27
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Stoyek MR, Croll RP, Smith FM. Intrinsic and extrinsic innervation of the heart in zebrafish (Danio rerio). J Comp Neurol 2015; 523:1683-700. [PMID: 25711945 DOI: 10.1002/cne.23764] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 02/16/2015] [Accepted: 02/18/2015] [Indexed: 01/22/2023]
Abstract
In the vertebrate heart the intracardiac nervous system is the final common pathway for autonomic control of cardiac output, but the neuroanatomy of this system is not well understood. In this study we investigated the innervation of the heart in a model vertebrate, the zebrafish. We used antibodies against acetylated tubulin, human neuronal protein C/D, choline acetyltransferase, tyrosine hydroxylase, neuronal nitric oxide synthase, and vasoactive intestinal polypeptide to visualize neural elements and their neurotransmitter content. Most neurons were located at the venous pole in a plexus around the sinoatrial valve; mean total number of cells was 197 ± 23, and 92% were choline acetyltransferase positive, implying a cholinergic role. The plexus contained cholinergic, adrenergic, and nitrergic axons and vasoactive intestinal polypeptide-positive terminals, some innervating somata. Putative pacemaker cells near the plexus showed immunoreactivity for hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) and the transcription factor Islet-1 (Isl1). The neurotracer neurobiotin showed that extrinsic axons from the left and right vagosympathetic trunks innervated the sinoatrial plexus proximal to their entry into the heart; some extrinsic axons from each trunk also projected into the medial dorsal plexus region. Extrinsic axons also innervated the atrial and ventricular walls. An extracardiac nerve trunk innervated the bulbus arteriosus and entered the arterial pole of the heart to innervate the proximal ventricle. We have shown that the intracardiac nervous system in the zebrafish is anatomically and neurochemically complex, providing a substrate for autonomic control of cardiac effectors in all chambers.
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Affiliation(s)
- Matthew R Stoyek
- Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Roger P Croll
- Department of Physiology and Biophysics; Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Frank M Smith
- Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
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28
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Reyes C, Fong AY, Milsom WK. Distribution and innervation of putative peripheral arterial chemoreceptors in the red-eared slider (Trachemys scripta elegans). J Comp Neurol 2015; 523:1399-418. [DOI: 10.1002/cne.23743] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 01/07/2015] [Accepted: 01/07/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Catalina Reyes
- Department of Zoology; University of British Columbia; Vancouver British Columbia, Vancouver Canada V6T 1Z4
| | - Angelina Y. Fong
- Department of Physiology; University of Melbourne; Parkville Victoria 3010 Australia
| | - William K. Milsom
- Department of Zoology; University of British Columbia; Vancouver British Columbia, Vancouver Canada V6T 1Z4
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29
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Abdallah SJ, Thomas BS, Jonz MG. Aquatic surface respiration and swimming behaviour in adult and developing zebrafish exposed to hypoxia. J Exp Biol 2015; 218:1777-86. [DOI: 10.1242/jeb.116343] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 04/14/2015] [Indexed: 11/20/2022]
Abstract
Severe hypoxia elicits aquatic surface respiration (ASR) behaviour in many species of fish, where ventilation of the gills at the air-water interface improves O2 uptake and survival. ASR is an important adaptation that may have given rise to air breathing in vertebrates. The neural substrate of this behaviour, however, is not defined. We characterized ASR in developing and adult zebrafish (Danio rerio) to ascertain a potential role for peripheral chemoreceptors in initiation or modulation of this response. Adult zebrafish exposed to acute, progressive hypoxia (PO2 from 158 to 15 mmHg) performed ASR with a threshold of 30 mmHg, and spent more time at the surface as PO2 decreased. Acclimation to hypoxia attenuated ASR responses. In larvae, ASR behaviour was observed between 5 and 21 days postfertilization with a threshold of 16 mmHg. Zebrafish decreased swimming behaviour (i.e. distance, velocity and acceleration) as PO2 was decreased, with a secondary increase in behaviour near or below threshold PO2. In adults that underwent a 10-day intraperitoneal injection regime of 10 µg g−1 serotonin (5-HT) or 20 µg g−1 acetylcholine (ACh), an acute bout of hypoxia (15 mmHg) increased the time engaged in ASR by 5.5 and 4.9 times, respectively, compared to controls. Larvae previously immersed in 10 µmol l−1 5-HT or ACh also displayed an increased ASR response. Our results support the notion that ASR is a behavioural response that is reliant upon input from peripheral O2 chemoreceptors. We discuss implications for the role of chemoreceptors in the evolution of air breathing.
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Affiliation(s)
- Sara J. Abdallah
- Department of Biology, University of Ottawa, Ottawa, ON, Canada, K1N 6N5
| | - Benjamin S. Thomas
- Department of Biology, University of Ottawa, Ottawa, ON, Canada, K1N 6N5
| | - Michael G. Jonz
- Department of Biology, University of Ottawa, Ottawa, ON, Canada, K1N 6N5
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30
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Cousin MA, Ebbert JO, Wiinamaki AR, Urban MD, Argue DP, Ekker SC, Klee EW. Larval zebrafish model for FDA-approved drug repositioning for tobacco dependence treatment. PLoS One 2014; 9:e90467. [PMID: 24658307 PMCID: PMC3962344 DOI: 10.1371/journal.pone.0090467] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Accepted: 02/03/2014] [Indexed: 12/18/2022] Open
Abstract
Cigarette smoking remains the most preventable cause of death and excess health care costs in the United States, and is a leading cause of death among alcoholics. Long-term tobacco abstinence rates are low, and pharmacotherapeutic options are limited. Repositioning medications approved by the U.S. Food and Drug Administration (FDA) may efficiently provide clinicians with new treatment options. We developed a drug-repositioning paradigm using larval zebrafish locomotion and established predictive clinical validity using FDA-approved smoking cessation therapeutics. We evaluated 39 physician-vetted medications for nicotine-induced locomotor activation blockade. We further evaluated candidate medications for altered ethanol response, as well as in combination with varenicline for nicotine-response attenuation. Six medications specifically inhibited the nicotine response. Among this set, apomorphine and topiramate blocked both nicotine and ethanol responses. Both positively interact with varenicline in the Bliss Independence test, indicating potential synergistic interactions suggesting these are candidates for translation into Phase II clinical trials for smoking cessation.
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Affiliation(s)
- Margot A. Cousin
- Mayo Addiction Research Center, Mayo Clinic, Rochester, Minnesota, United States of America
- Center for Clinical and Translational Science, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Jon O. Ebbert
- Mayo Addiction Research Center, Mayo Clinic, Rochester, Minnesota, United States of America
- Nicotine Dependence Center, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Amanda R. Wiinamaki
- Mayo Addiction Research Center, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Mark D. Urban
- Mayo Addiction Research Center, Mayo Clinic, Rochester, Minnesota, United States of America
| | - David P. Argue
- Mayo Addiction Research Center, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Stephen C. Ekker
- Mayo Addiction Research Center, Mayo Clinic, Rochester, Minnesota, United States of America
- Center for Clinical and Translational Science, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Eric W. Klee
- Mayo Addiction Research Center, Mayo Clinic, Rochester, Minnesota, United States of America
- Center for Clinical and Translational Science, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail:
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