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Khalilpour J, Soltani Zangbar H, Alipour MR, Shahabi P. The hypoxic respiratory response of the pre-Bötzinger complex. Heliyon 2024; 10:e34491. [PMID: 39114066 PMCID: PMC11305331 DOI: 10.1016/j.heliyon.2024.e34491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/18/2024] [Accepted: 07/10/2024] [Indexed: 08/10/2024] Open
Abstract
Since the discovery of the pre-Bötzinger Complex (preBötC) as a crucial region for generating the main respiratory rhythm, our understanding of its cellular and molecular aspects has rapidly increased within the last few decades. It is now apparent that preBötC is a highly flexible neuronal network that reconfigures state-dependently to produce the most appropriate respiratory output in response to various metabolic challenges, such as hypoxia. However, the responses of the preBötC to hypoxic conditions can be varied based on the intensity, pattern, and duration of the hypoxic challenge. This review discusses the preBötC response to hypoxic challenges at the cellular and network level. Particularly, the involvement of preBötC in the classical biphasic response of the respiratory network to acute hypoxia is illuminated. Furthermore, the article discusses the functional and structural changes of preBötC neurons following intermittent and sustained hypoxic challenges. Accumulating evidence shows that the preBötC neural circuits undergo substantial changes following hypoxia and contribute to several types of the respiratory system's hypoxic ventilatory responses.
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Affiliation(s)
- Jamal Khalilpour
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamid Soltani Zangbar
- Department of Neuroscience, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Parviz Shahabi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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2
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Viemari JC. Isoproterenol modulates expiratory activities in the brainstem spinal cord preparation in neonatal mice in vitro. Respir Physiol Neurobiol 2024; 324:104241. [PMID: 38417565 DOI: 10.1016/j.resp.2024.104241] [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: 10/26/2023] [Revised: 02/12/2024] [Accepted: 02/23/2024] [Indexed: 03/01/2024]
Abstract
Motor behaviors such as breathing required temporal coordination of different muscle groups to insured efficient ventilation and provide oxygen to the body. This action is the result of interactions between neural networks located within the brainstem. Inspiration and expiration depend at least in part on interactions between two separate oscillators: inspiration is driven by a neural network located in the preBötzinger complex (PreBötC) and active expiration is driven by a network in the parafacial respiratory group (pFRG). Neurons of the pFRG are silent at rest and become active when the respiratory drive increased. This study investigated the temporal coordination between the brainstem respiratory network and the lumbar spinal network that generates spontaneous activities that is different of the induced fictive locomotion. The remaining question is how these activities coordinate early during the development. Results of this study show that brainstem networks contribute to the temporal coordination of the lumbar spontaneous activity during inspiration since lumbar motor activity occurs exclusively during the expiratory time. This study also investigated the role of the β-noradrenergic modulation on the respiratory activities. β-noradrenergic receptors activation increased the frequency of the double bursts and increased expiratory activity at the lumbar level. These results suggest interactions between brainstem and spinal networks and reveal a descending drive that may contribute to the coordination of the respiratory and lumbar spontaneous activities.
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Affiliation(s)
- Jean-Charles Viemari
- Aix-Marseille Univ, Inserm, MMG, Marseille, France; Aix-Marseille Univ, CNRS, INT, Marseille, France.
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3
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Oke Y, Miwakeichi F, Oku Y, Hirrlinger J, Hülsmann S. Cell types and synchronous-activity patterns of inspiratory neurons in the preBötzinger complex of mouse medullary slices during early postnatal development. Sci Rep 2023; 13:586. [PMID: 36631589 PMCID: PMC9834223 DOI: 10.1038/s41598-023-27893-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 01/10/2023] [Indexed: 01/13/2023] Open
Abstract
To examine whether and how the inspiratory neuronal network in the preBötzinger complex (preBötC) develops during the early postnatal period, we quantified the composition of the population of inspiratory neurons between postnatal day 1 (p1) and p10 by applying calcium imaging to medullary transverse slices in double-transgenic mice expressing fluorescent marker proteins. We found that putative excitatory and glycinergic neurons formed a majority of the population of inspiratory neurons, and the composition rates of these two inspiratory neurons inverted at p5-6. We also found that the activity patterns of these two types of inspiratory neurons became significantly well-synchronized with the inspiratory rhythmic bursting pattern in the preBötC within the first postnatal week. GABAergic and GABA-glycine cotransmitting inspiratory neurons formed only a small population just after birth, which almost disappeared until p10. In conclusion, the inspiratory neuronal network in the preBötC matures at the level of both neuronal population and neuronal activities during early postnatal development.
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Affiliation(s)
- Yoshihiko Oke
- Division of Physiome, Department of Physiology, Hyogo Medical University, 1-1 Mukogawa-cho, Nishinomiya, 663-8501, Japan.
| | - Fumikazu Miwakeichi
- grid.507381.80000 0001 1945 4756Department of Statistical Modeling, The Institute of Statistical Mathematics, 10-3, Midori-cho, Tachikawa, 190-0014 Japan ,grid.275033.00000 0004 1763 208XDepartment of Statistical Science, School of Multidisciplinary Sciences, The Graduate University for Advanced Studies, Shounan-Kokusai-Mura, Hayama-cho, Miura, 240-0193 Japan
| | - Yoshitaka Oku
- grid.272264.70000 0000 9142 153XDivision of Physiome, Department of Physiology, Hyogo Medical University, 1-1 Mukogawa-cho, Nishinomiya, 663-8501 Japan
| | - Johannes Hirrlinger
- grid.9647.c0000 0004 7669 9786Carl-Ludwig-Institute for Physiology, Faculty of Medicine, University of Leipzig, Liebigstraße 27, 04103 Leipzig, Germany ,grid.516369.eDepartment of Neurogenetics, Max Planck Institute for Multidisciplinary Science, Hermann-Rein-Straße 3, 37075 Göttingen, Germany
| | - Swen Hülsmann
- grid.411984.10000 0001 0482 5331Department of Anesthesiology, University Medical Center, Humboldtallee 23, 37073 Göttingen, Germany
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4
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Asante E, Hummel D, Gurung S, Kassim YM, Al-Shakarji N, Palaniappan K, Sittaramane V, Chandrasekhar A. Defective Neuronal Positioning Correlates With Aberrant Motor Circuit Function in Zebrafish. Front Neural Circuits 2021; 15:690475. [PMID: 34248505 PMCID: PMC8265374 DOI: 10.3389/fncir.2021.690475] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/01/2021] [Indexed: 11/18/2022] Open
Abstract
Precise positioning of neurons resulting from cell division and migration during development is critical for normal brain function. Disruption of neuronal migration can cause a myriad of neurological disorders. To investigate the functional consequences of defective neuronal positioning on circuit function, we studied a zebrafish frizzled3a (fzd3a) loss-of-function mutant off-limits (olt) where the facial branchiomotor (FBM) neurons fail to migrate out of their birthplace. A jaw movement assay, which measures the opening of the zebrafish jaw (gape), showed that the frequency of gape events, but not their amplitude, was decreased in olt mutants. Consistent with this, a larval feeding assay revealed decreased food intake in olt mutants, indicating that the FBM circuit in mutants generates defective functional outputs. We tested various mechanisms that could generate defective functional outputs in mutants. While fzd3a is ubiquitously expressed in neural and non-neural tissues, jaw cartilage and muscle developed normally in olt mutants, and muscle function also appeared to be unaffected. Although FBM neurons were mispositioned in olt mutants, axon pathfinding to jaw muscles was unaffected. Moreover, neuromuscular junctions established by FBM neurons on jaw muscles were similar between wildtype siblings and olt mutants. Interestingly, motor axons innervating the interhyoideus jaw muscle were frequently defasciculated in olt mutants. Furthermore, GCaMP imaging revealed that mutant FBM neurons were less active than their wildtype counterparts. These data show that aberrant positioning of FBM neurons in olt mutants is correlated with subtle defects in fasciculation and neuronal activity, potentially generating defective functional outputs.
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Affiliation(s)
- Emilia Asante
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Devynn Hummel
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Suman Gurung
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, United States.,Department of Pathology and Cell Biology, USF Health Heart Institute, University of South Florida, Tampa, Florida, FL, United States
| | - Yasmin M Kassim
- Computational Imaging and VisAnalysis (CIVA) Lab, Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, United States
| | - Noor Al-Shakarji
- Computational Imaging and VisAnalysis (CIVA) Lab, Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, United States
| | - Kannappan Palaniappan
- Computational Imaging and VisAnalysis (CIVA) Lab, Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, United States
| | - Vinoth Sittaramane
- Department of Biology, Georgia Southern University, Statesboro, GA, United States
| | - Anand Chandrasekhar
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
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5
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Taxini CL, Marques DA, Bícego KC, Gargaglioni LH. A5 noradrenergic neurons and breathing control in neonate rats. Pflugers Arch 2021; 473:859-872. [PMID: 33855632 DOI: 10.1007/s00424-021-02550-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 02/16/2021] [Accepted: 02/25/2021] [Indexed: 10/21/2022]
Abstract
The pontine A5 noradrenergic group contributes to the maturation of the respiratory system before birth in rats. These neurons are connected to the neural network responsible for respiratory rhythmogenesis. In the present study, we investigated the participation of A5 noradrenergic neurons in neonates (P7-8 and P14-15) in the control of ventilation during hypoxia and hypercapnia in in vivo experiments using conjugated saporin anti-dopamine beta-hydroxylase (DβH-SAP) to specifically ablate noradrenergic neurons. Thus, DβH-SAP (420 ng/μL) or saporin (SAP, control) was injected into the A5 region of neonatal male Wistar rats. Hypoxia reduced respiratory variability in control animals; however, A5 lesion prevented this effect in P7-8 rats. Our data suggest that noradrenergic neurons of the A5 region in neonate rats do not participate in the control of ventilation under baseline and hypercapnic conditions, but exert an inhibitory modulation on breathing variability under hypoxic challenge in early life (P7-8).
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Affiliation(s)
- Camila L Taxini
- Department of Morphology and Animal Physiology - FCAV, São Paulo State University (UNESP), Via de acesso Paulo Donato Castellane s/n, Jaboticabal, SP, 14870-900, Brazil
| | - Danuzia A Marques
- Department of Pediatrics, Centre de Recherche de L'Institut Universitaire de Cardiologie Et de Pneumologie de Québec, Université Laval, Québec, G1V 4G5, Canada
| | - Kênia C Bícego
- Department of Morphology and Animal Physiology - FCAV, São Paulo State University (UNESP), Via de acesso Paulo Donato Castellane s/n, Jaboticabal, SP, 14870-900, Brazil
| | - Luciane H Gargaglioni
- Department of Morphology and Animal Physiology - FCAV, São Paulo State University (UNESP), Via de acesso Paulo Donato Castellane s/n, Jaboticabal, SP, 14870-900, Brazil.
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6
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Wang W, Alzate-Correa D, Alves MJ, Jones M, Garcia AJ, Zhao J, Czeisler CM, Otero JJ. Machine learning-based data analytic approaches for evaluating post-natal mouse respiratory physiological evolution. Respir Physiol Neurobiol 2020; 283:103558. [PMID: 33010456 DOI: 10.1016/j.resp.2020.103558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/24/2020] [Accepted: 09/26/2020] [Indexed: 11/16/2022]
Abstract
Respiratory parameters change during post-natal development, but the nature of their changes have not been well-described. The advent of commercially available plethysmographic instruments provided improved repeatability of measurements and standardization of measured breathing in mice across laboratories. These technologies thus allowed for exploration of more precise respiratory pattern changes during the post-natal developmental epoch. Current methods to analyze respiratory behavior utilize plethysmography to acquire standing values of frequency, volume and flow at specific time points in murine maturation. These metrics have historically been independently analyzed as a function of time with no further analysis examining the interplay these variables have with each other and in the context of postnatal maturation or during blood gas homeostasis. We posit that machine learning workflows can provide deeper physiological understanding into the postnatal development of respiration. In this manuscript, we delineate a machine learning workflow based on the R-statistical programming language to examine how variation and relationships of frequency (f) and tidal volume (TV) change with respect to inspiratory and expiratory parameters. Our analytical workflows could successfully predict age and found that the variation and relationships between respiratory metrics are dynamically shifting with age and during hypercapnic breathing. Thus, our work demonstrates the utility of high dimensional analyses to provide reliable class label predictions using non-invasive respiratory metrics. These approaches may be useful in large-scale phenotyping across development and in disease.
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Affiliation(s)
- Wesley Wang
- Department of Pathology, Division of Neuropathology, The Ohio State University College of Medicine, Columbus, OH, United States
| | - Diego Alzate-Correa
- Department of Pathology, Division of Neuropathology, The Ohio State University College of Medicine, Columbus, OH, United States
| | - Michele Joana Alves
- Department of Pathology, Division of Neuropathology, The Ohio State University College of Medicine, Columbus, OH, United States
| | - Mikayla Jones
- Department of Pathology, Division of Neuropathology, The Ohio State University College of Medicine, Columbus, OH, United States
| | - Alfredo J Garcia
- Department of Emergency Medicine, University of Chicago, Chicago, IL, United States
| | - Jing Zhao
- Department of Biomedical Informatics, The Ohio State University College of Medicine, Columbus, OH, United States
| | - Catherine Miriam Czeisler
- Department of Pathology, Division of Neuropathology, The Ohio State University College of Medicine, Columbus, OH, United States.
| | - José Javier Otero
- Department of Pathology, Division of Neuropathology, The Ohio State University College of Medicine, Columbus, OH, United States.
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7
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Szoták-Ajtay K, Szõke D, Kovács G, Andréka J, Brenner GB, Giricz Z, Penninger J, Kahn ML, Jakus Z. Reduced Prenatal Pulmonary Lymphatic Function Is Observed in Clp1 K/K Embryos With Impaired Motor Functions Including Fetal Breathing Movements in Preparation of the Developing Lung for Inflation at Birth. Front Bioeng Biotechnol 2020; 8:136. [PMID: 32211389 PMCID: PMC7067749 DOI: 10.3389/fbioe.2020.00136] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 02/11/2020] [Indexed: 11/13/2022] Open
Abstract
Embryonic lungs must be inflated immediately after birth to establish respiration. In addition to pulmonary surfactant, recently, we have revealed lymphatic function as a previously unknown regulator of prenatal lung compliance that prepares the embryonic lung for inflation at birth. It is well-documented that the late gestation embryo performs episodic breathing-like movements called as fetal breathing movements (FBMs), but the physiological importance of these events is not clear. Here we aimed to study the physiological role of FBMs in preparation for air inflation at birth. Clp1K/K late gestation embryos develop a progressive loss of spinal motor neurons associated with axonal degeneration and denervation of neuromuscular junctions serving as an ideal genetic model to test the possible role of FBMs. We demonstrated that Clp1K/K newborns show impaired motor function resulting in fatal respiratory failure after birth. Next, we showed that the alveolar septa are thicker, and the alveolar area is reduced in Clp1K/K late gestation embryos, while the expression of molecular markers of lung development are not affected. Importantly, pulmonary lymphatic vessels are dilated and the prenatal pulmonary lymphatic function is reduced in Clp1K/K late gestation embryos. Our results have revealed that Clp1K/K mice show impaired motor functions including FBMs, and late gestation Clp1K/K embryos display reduced prenatal lymphatic function and impaired lung expansion represented as thickened alveolar septa and reduced alveolar area in preparation of the developing lung for inflation at birth. These findings suggest a possible mechanism that FBMs, similarly to breathing movements after birth, stimulate prenatal lymphatic function in pulmonary collecting lymphatics lacking smooth muscle coverage to prepare the developing lung for inflation and gas exchange at birth. Moreover, these results raise the possibility that stimulating FBMs during late gestation might be an effective way to reduce the risk of the development of neonatal respiratory failure.
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Affiliation(s)
- Kitti Szoták-Ajtay
- Department of Physiology, Semmelweis University School of Medicine, Budapest, Hungary.,MTA-SE "Lendület" Lymphatic Physiology Research Group of the Hungarian Academy of Sciences and the Semmelweis University, Budapest, Hungary
| | - Dániel Szõke
- Department of Physiology, Semmelweis University School of Medicine, Budapest, Hungary.,MTA-SE "Lendület" Lymphatic Physiology Research Group of the Hungarian Academy of Sciences and the Semmelweis University, Budapest, Hungary
| | - Gábor Kovács
- Department of Physiology, Semmelweis University School of Medicine, Budapest, Hungary.,MTA-SE "Lendület" Lymphatic Physiology Research Group of the Hungarian Academy of Sciences and the Semmelweis University, Budapest, Hungary
| | - Judit Andréka
- Department of Physiology, Semmelweis University School of Medicine, Budapest, Hungary.,MTA-SE "Lendület" Lymphatic Physiology Research Group of the Hungarian Academy of Sciences and the Semmelweis University, Budapest, Hungary
| | - Gábor B Brenner
- Department of Pharmacology and Pharmacotherapy, Semmelweis University School of Medicine, Budapest, Hungary
| | - Zoltán Giricz
- Department of Pharmacology and Pharmacotherapy, Semmelweis University School of Medicine, Budapest, Hungary
| | - Josef Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria.,Department of Medical Genetics, Life Science Institute, University of British Columbia, Vancouver, BC, Canada
| | - Mark L Kahn
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Zoltán Jakus
- Department of Physiology, Semmelweis University School of Medicine, Budapest, Hungary.,MTA-SE "Lendület" Lymphatic Physiology Research Group of the Hungarian Academy of Sciences and the Semmelweis University, Budapest, Hungary
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8
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Bittencourt‐Silva PG, Menezes MF, Mendonça‐Junior BA, Karlen‐Amarante M, Zoccal DB. Postnatal intermittent hypoxia enhances phrenic and reduces vagal upper airway motor activities in rats by epigenetic mechanisms. Exp Physiol 2019; 105:148-159. [DOI: 10.1113/ep087928] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 10/08/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Paloma G. Bittencourt‐Silva
- Department of Physiology and Pathology School of Dentistry of Araraquara São Paulo State University (UNESP) Araraquara Brazil
| | - Miguel Furtado Menezes
- Department of Physiology and Pathology School of Dentistry of Araraquara São Paulo State University (UNESP) Araraquara Brazil
| | - Bolival A. Mendonça‐Junior
- Department of Physiology and Pathology School of Dentistry of Araraquara São Paulo State University (UNESP) Araraquara Brazil
| | - Marlusa Karlen‐Amarante
- Department of Physiology and Pathology School of Dentistry of Araraquara São Paulo State University (UNESP) Araraquara Brazil
| | - Daniel B. Zoccal
- Department of Physiology and Pathology School of Dentistry of Araraquara São Paulo State University (UNESP) Araraquara Brazil
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9
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Niblock MM, Perez A, Broitman S, Jacoby B, Aviv E, Gilkey S. In utero development of fetal breathing movements in C57BL6 mice. Respir Physiol Neurobiol 2019; 271:103288. [PMID: 31505274 DOI: 10.1016/j.resp.2019.103288] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/06/2019] [Accepted: 09/05/2019] [Indexed: 11/18/2022]
Abstract
Fetuses of many species, including humans, breathe during development. This fetal breathing aids in lung development, strengthens respiratory muscles, and is posited to fine-tune the neural circuitry that drives breathing. Previous studies suggested that fetal breathing could begin as early as the fifteenth day of gestation in the mouse, but fetal breathing movements (FBMs) had not been observed in mice in utero. We aimed to determine if and when FBMs commence in mice and if they change over time. We examined unanesthetised pregnant C57BL6 mice with ultrasound beginning on the seventh day of gestation. We first reliably observed episodic FBMs in mice on embryonic day 16. FBMs were sporadic, clustered, or rhythmic, and their frequency increased with age. Ultrasound examination of FBMs in mice has great potential utility in the study of transgenic mouse models to help us understand the prenatal characteristics of breathing related human developmental disorders, including Congenital Central Hypoventilation Syndrome (CCHS) and apnea of prematurity.
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Affiliation(s)
- Mary M Niblock
- Department of Biology, Dickinson College, Carlisle, PA, United States; Neuroscience Program, Dickinson College, Carlisle, PA, United States.
| | - Alanis Perez
- Department of Biology, Dickinson College, Carlisle, PA, United States
| | - Shahar Broitman
- Neuroscience Program, Dickinson College, Carlisle, PA, United States
| | - Brigitte Jacoby
- Neuroscience Program, Dickinson College, Carlisle, PA, United States; Biochemistry and Molecular Biology Program, Dickinson College, Carlisle, PA, United States
| | - Elana Aviv
- Department of Biology, Dickinson College, Carlisle, PA, United States
| | - Sydney Gilkey
- Neuroscience Program, Dickinson College, Carlisle, PA, United States; Biochemistry and Molecular Biology Program, Dickinson College, Carlisle, PA, United States
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10
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Sex differences in breathing. Comp Biochem Physiol A Mol Integr Physiol 2019; 238:110543. [PMID: 31445081 DOI: 10.1016/j.cbpa.2019.110543] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 08/08/2019] [Accepted: 08/09/2019] [Indexed: 01/15/2023]
Abstract
Breathing is a vital behavior that ensures both the adequate supply of oxygen and the elimination of CO2, and it is influenced by many factors. Despite that most of the studies in respiratory physiology rely heavily on male subjects, there is much evidence to suggest that sex is an important factor in the respiratory control system, including the susceptibility for some diseases. These different respiratory responses in males and females may be related to the actions of sex hormones, especially in adulthood. These hormones affect neuromodulatory systems that influence the central medullary rhythm/pontine pattern generator and integrator, sensory inputs to the integrator and motor output to the respiratory muscles. In this article, we will first review the sex dependence on the prevalence of some respiratory-related diseases. Then, we will discuss the role of sex and gonadal hormones in respiratory control under resting conditions and during respiratory challenges, such as hypoxia and hypercapnia, and whether hormonal fluctuations during the estrous/menstrual cycle affect breathing control. We will then discuss the role of the locus coeruleus, a sexually dimorphic CO2/pH-chemosensitive nucleus, on breathing regulation in males and females. Next, we will highlight the studies that exist regarding sex differences in respiratory control during development. Finally, the few existing studies regarding the influence of sex on breathing control in non-mammalian vertebrates will be discussed.
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11
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Garcia AJ, Viemari JC, Khuu MA. Respiratory rhythm generation, hypoxia, and oxidative stress-Implications for development. Respir Physiol Neurobiol 2019; 270:103259. [PMID: 31369874 DOI: 10.1016/j.resp.2019.103259] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 07/15/2019] [Accepted: 07/24/2019] [Indexed: 02/07/2023]
Abstract
Encountered in a number of clinical conditions, repeated hypoxia/reoxygenation during the neonatal period can pose both a threat to immediate survival as well as a diminished quality of living later in life. This review focuses on our current understanding of central respiratory rhythm generation and the role that hypoxia and reoxygenation play in influencing rhythmogenesis. Here, we examine the stereotypical response of the inspiratory rhythm from the preBötzinger complex (preBötC), basic neuronal mechanisms that support rhythm generation during the peri-hypoxic interval, and the physiological consequences of inspiratory network responsivity to hypoxia and reoxygenation, acute and chronic intermittent hypoxia, and oxidative stress. These topics are examined in the context of Sudden Infant Death Syndrome, apneas of prematurity, and neonatal abstinence syndrome.
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Affiliation(s)
- Alfredo J Garcia
- Institute for Integrative Physiology, Section of Emergency Medicine, The University of Chicago, Chicago, 60637, IL, United States
| | - Jean Charles Viemari
- Institut de Neurosciences de la Timone, P3M team, UMR7289 CNRS & AMU, Faculté de Médecine de la Timone, 27 Bd Jean Moulin, Marseille, 13005, France
| | - Maggie A Khuu
- Institute for Integrative Physiology, Section of Emergency Medicine, The University of Chicago, Chicago, 60637, IL, United States
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12
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Schneider Gasser EM, Elliot-Portal E, Arias-Reyes C, Losantos-Ramos K, Khalid K, Ogunshola O, Soliz J. Developmental expression patterns of erythropoietin and its receptor in mouse brainstem respiratory regions. Respir Physiol Neurobiol 2019; 267:12-19. [PMID: 31154093 DOI: 10.1016/j.resp.2019.05.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/23/2019] [Accepted: 05/20/2019] [Indexed: 12/14/2022]
Abstract
Erythropoietin (EPO) is a hypoxia-inducible hormone, classically known to enhance red blood cell production upon binding its receptor (EPOR) present on the surface of the erythroid progenitor cells. EPO and its receptor are also expressed in the central nervous system (CNS), exerting several non-hematopoietic actions. EPO also plays an important role in the control of breathing. In this review, we summarize the known physiological actions of EPO in the neural control of ventilation during postnatal development and at adulthood in rodents under normoxic and hypoxic conditions. Furthermore, we present the developmental expression patterns of EPO and EPORs in the brainstem, and with the use of in situ hybridization (ISH) and immunofluorescence techniques we provide original data showing that EPOR is abundantly present in specific brainstem nuclei associated with central chemosensitivity and control of ventilation in the ventrolateral medulla, mainly on somatostatin negative cells. Thus, we conclude that EPO signaling may act through glutamatergic neuron populations that are the primary source of rhythmic inspiratory excitatory drive. This work underlies the importance of EPO signaling in the central control of ventilation across development and adulthood and provides new insights on the expression of EPOR at the cellular level.
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Affiliation(s)
- Edith M Schneider Gasser
- Institute of Pharmacology and Toxicology, University of Zürich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Elizabeth Elliot-Portal
- Institut universitaire de cardiologie et de pneumologie de Québec, Centre Hospitalier Universitaire de Québec (CHUQ), Faculty of Medicine, Université Laval, Québec, QC, Canada
| | - Christian Arias-Reyes
- Institut universitaire de cardiologie et de pneumologie de Québec, Centre Hospitalier Universitaire de Québec (CHUQ), Faculty of Medicine, Université Laval, Québec, QC, Canada; Instituto de Biología Molecular y Biotecnología, Facultad de Ciencias Puras y Naturales, Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Karen Losantos-Ramos
- Institut universitaire de cardiologie et de pneumologie de Québec, Centre Hospitalier Universitaire de Québec (CHUQ), Faculty of Medicine, Université Laval, Québec, QC, Canada
| | - Kasifa Khalid
- Institute of Pharmacology and Toxicology, University of Zürich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Omolara Ogunshola
- Institute of Veterinary Physiology and Zurich Center of Integrative Human Physiology (ZIHP), Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland
| | - Jorge Soliz
- Institut universitaire de cardiologie et de pneumologie de Québec, Centre Hospitalier Universitaire de Québec (CHUQ), Faculty of Medicine, Université Laval, Québec, QC, Canada; Instituto de Biología Molecular y Biotecnología, Facultad de Ciencias Puras y Naturales, Universidad Mayor de San Andrés, La Paz, Bolivia.
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13
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Patrone LGA, Biancardi V, Marques DA, Bícego KC, Gargaglioni LH. Brainstem catecholaminergic neurones and breathing control during postnatal development in male and female rats. J Physiol 2018; 596:3299-3325. [PMID: 29479699 DOI: 10.1113/jp275731] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 02/21/2018] [Indexed: 01/23/2023] Open
Abstract
KEY POINTS The brainstem catecholaminergic (CA) modulation on ventilation changes with development. We determined the role of the brainstem CA system in ventilatory control under normocapnic and hypercapnic conditions during different phases of development [postnatal day (P)7-8, P14-15 and P20-21] in male and female Wistar rats. Brainstem CA neurones produce a tonic inhibitory drive that affects breathing frequency in P7-8 rats and provide an inhibitory drive during hypercapnic conditions in both males and females at P7-8 and P14-15. In pre-pubertal rats, brainstem CA neurones become excitatory for the CO2 ventilatory response in males but remain inhibitory in females. Diseases such as sudden infant death syndrome, congenital central hypoventilation syndrome and Rett syndrome have been associated with abnormalities in the functioning of CA neurones; therefore, the results of the present study contribute to a better understanding of this system. ABSTRACT The respiratory network undergoes significant development during the postnatal phase, including the maturation of the catecholaminergic (CA) system. However, postnatal development of this network and its effect on the control of pulmonary ventilation ( V̇E ) is not fully understood. We investigated the involvement of brainstem CA neurones in respiratory control during postnatal development [postnatal day (P)7-8, P14-15 and P20-21], in male and female rats, through chemical injury with conjugated saporin anti-dopamine β-hydroxylase (DβH-SAP). Thus, DβH-SAP (420 ng μL-1 ), saporin (SAP) or phosphate buffered solution (PBS) was injected into the fourth ventricle of neonatal Wistar rats of both sexes. V̇E and oxygen consumption were recorded 1 week after the injections in unanaesthetized neonatal and juvenile rats during room air and hypercapnia. The resting ventilation was higher in both male and female P7-8 lesioned rats by 33%, with a decrease in respiratory variability being observed in males. The hypercapnic ventilatory response (HCVR) was altered in male and female lesioned rats at all postnatal ages. At P7-8, the HCVR for males and females was increased by 37% and 30%, respectively. For both sexes at P14-15 rats, the increase in V̇E during hypercapnia was 37% higher for lesioned rats. A sex-specific difference in HCRV was observed at P20-21, with lesioned males showing a 33% decrease, and lesioned females showing an increase of 33%. We conclude that brainstem CA neurones exert a tonic inhibitory effect on V̇E in the early postnatal days of the life of a rat, increase variability in P7-8 males and modulate HCRV during the postnatal phase.
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Affiliation(s)
- Luis Gustavo A Patrone
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV at Jaboticabal, SP, Brazil
| | - Vivian Biancardi
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV at Jaboticabal, SP, Brazil
| | - Danuzia A Marques
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV at Jaboticabal, SP, Brazil
| | - Kênia C Bícego
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV at Jaboticabal, SP, Brazil
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV at Jaboticabal, SP, Brazil
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Rousseau JP, Tenorio-Lopes L, Baldy C, Janes TA, Fournier S, Kinkead R. On the origins of sex-based differences in respiratory disorders: Lessons and hypotheses from stress neuroendocrinology in developing rats. Respir Physiol Neurobiol 2017; 245:105-121. [DOI: 10.1016/j.resp.2017.03.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 03/28/2017] [Accepted: 03/31/2017] [Indexed: 12/31/2022]
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15
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Landry-Truchon K, Fournier S, Houde N, Rousseau JP, Jeannotte L, Kinkead R. Respiratory consequences of targeted losses of Hoxa5 gene function in mice. ACTA ACUST UNITED AC 2017; 220:4571-4577. [PMID: 29074702 DOI: 10.1242/jeb.165084] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 10/23/2017] [Indexed: 12/17/2022]
Abstract
Fetal development of the respiratory tract and diaphragm requires strict coordination between genetically controlled signals and mechanical forces produced by the neural network that generates breathing. HOXA5, which is expressed in the mesenchyme of the trachea, lung and diaphragm, and in phrenic motor neurons, is a key transcription factor regulating lung development and function. Consequently, most Hoxa5-/- mutants die at birth from respiratory failure. However, the extensive effect of the null mutation makes it difficult to identify the origins of respiratory dysfunction in newborns. To address the physiological impact of Hoxa5 tissue-specific roles, we used conditional gene targeting with the Dermo1Cre and Olig2Cre mouse lines to produce specific Hoxa5 deletions in the mesenchyme and motor neurons, respectively. Hoxa5 expression in the mesenchyme is critical for trachea development, whereas its expression in phrenic motor neurons is essential for diaphragm formation. Breathing measurements in adult mice with whole-body plethysmography demonstrated that, at rest, only the motor neuron deletion affects respiration, resulting in higher breathing frequency and decreased tidal volume. But subsequent exposure to a moderate hypoxic challenge (FiO2 =0.12; 10 min) revealed that both mutant mice hyperventilate more than controls. Hoxa5flox/flox;Dermo1+/Cre mice showed augmented tidal volume while Hoxa5flox/flox;Olig2+/Cre mice had the largest increase in breathing frequency. No significant differences were observed between medulla-spinal cord preparations from E18.5 control and Hoxa5flox/flox;Olig2+/Cre mouse embryos that could support a role for Hoxa5 in fetal inspiratory motor command. According to our data, Hoxa5 expression in the mesenchyme and phrenic motor neurons controls distinct aspects of respiratory development.
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Affiliation(s)
- Kim Landry-Truchon
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, Hôtel-Dieu de Québec, Québec, QC, Canada, G1R 3S3.,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec, QC, Canada, G1V 0A6
| | - Stéphanie Fournier
- CRIUCPQ, Québec, QC, Canada, G1V 4G5.,Department of Pediatrics, Université Laval, Québec, QC, Canada, G1V 0A6
| | - Nicolas Houde
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, Hôtel-Dieu de Québec, Québec, QC, Canada, G1R 3S3.,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec, QC, Canada, G1V 0A6
| | - Jean-Philippe Rousseau
- CRIUCPQ, Québec, QC, Canada, G1V 4G5.,Department of Pediatrics, Université Laval, Québec, QC, Canada, G1V 0A6
| | - Lucie Jeannotte
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, Hôtel-Dieu de Québec, Québec, QC, Canada, G1R 3S3 .,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec, QC, Canada, G1V 0A6
| | - Richard Kinkead
- CRIUCPQ, Québec, QC, Canada, G1V 4G5 .,Department of Pediatrics, Université Laval, Québec, QC, Canada, G1V 0A6
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Erythropoietin-Mediated Regulation of Central Respiratory Command. VITAMINS AND HORMONES 2017. [PMID: 28629514 DOI: 10.1016/bs.vh.2017.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Erythropoietin (Epo) is a cytokine expressed throughout the body, including in the central nervous system where it can act as a breathing modulator in the central respiratory network. In vitro, Epo allows maintaining the activity of respiratory neurons during acute hypoxia, resulting in inhibition of the hypoxia-induced rhythm depression. In vivo, Epo action on the central respiratory command results in enhancement of the acute hypoxic ventilatory response, allowing a better oxygenation of the body by improvement of gases exchanges in the lungs. Importantly, this effect of Epo is age-dependent, being observed at adulthood and at both early and late postnatal ages, but not at middle postnatal ages, when an important setup of the central respiratory command occurs. Epo regulation of the central respiratory command involves at least two intracellular signaling pathways, PI3K-Akt and MEK-ERK pathways. However, the exact mechanism underlying the action of Epo on the central respiratory control remains to be deciphered, as well as the exact cell types and nuclei involved in this control. Epo-mediated effect on the central respiratory command is regulated by several factors, including hypoxia, sex hormones, and an endogen antagonist. Although more knowledge is needed before reaching the clinical trial step, Epo seems to be a promising therapeutic treatment, notably against newborn breathing disorders.
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17
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Laouafa S, Perrin-Terrin AS, Jeton F, Elliot-Portal E, Tam R, Bodineau L, Voituron N, Soliz J. Pharmacological, but not genetic, alteration of neural Epo modifies the CO 2/H + central chemosensitivity in postnatal mice. Respir Physiol Neurobiol 2017; 242:73-79. [PMID: 28396201 DOI: 10.1016/j.resp.2017.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 03/24/2017] [Accepted: 04/05/2017] [Indexed: 11/24/2022]
Abstract
Cerebral erythropoietin (Epo) plays a crucial role for respiratory control in newborn rodents. We showed previously that soluble Epo receptor (sEpoR: an Epo antagonist) reduces basal ventilation and hypoxic hyperventilation at postnatal day 10 (P10) and in adult mice. However, at these ages (P10 and adulthood), Epo had no effect on central chemosensitivity. Nevertheless, it is known that the sensitivity to CO2/H+ during the mammalian respiratory network maturation process is age-dependent. Accordingly, in this study we wanted to test the hypothesis that cerebral Epo is involved in the breathing stimulation induced by the activation of central CO2/H+ chemoreceptors at earlier postnatal ages. To this end, en bloc brainstem-spinal cord preparations were obtained from P4 mice and the fictive breathing response to CO2-induced acidosis or metabolic acidosis was analyzed. This age (P4) was chosen because previous research from our laboratory showed that Epo altered (in a dose- and time-dependent manner) the fictive ventilation elicited in brainstem-spinal cord preparations. Moreover, as it was observed that peripheral chemoreceptors determined the respiratory sensitivity of central chemoreceptors to CO2, the use of this technique restricts our observations to central modulation. Our results did not show differences between preparations from control and transgenic animals (Tg21: overexpressing cerebral Epo; Epo-TAgh: cerebral Epo deficient mice). However, when Tg21 brainstem preparations were incubated for 1h with sEpoR, or with inhibitors of ERK/Akt (thus blocking the activation of the Epo molecular pathway), the fictive breathing response to CO2-induced acidosis was blunted. Our data suggest that variation of the Epo/sEpoR ratio is central to breathing modulation during CO2 challenges, and calls attention to clinical perspectives based on the use of Epo drugs at birth in hypoventilation cases.
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Affiliation(s)
- Sofien Laouafa
- Université Laval, Faculté de Médecine, Centre de Recherche Institut universitaire de cardiologie et de pneumologie de Québec, Département de Pédiatrie, Québec, QC, Canada; LEHNA, UMR CNRS 5023, Ecologie des Hydrosystèmes Naturels et Anthropisés, Université de Lyon, Université Lyon 1, ENTPE, 6 rue Raphael Dubois, 69622 Villeurbanne, France
| | - Anne-Sophie Perrin-Terrin
- Université Paris 13, Sorbonne Paris Cité, UFR SMBH, Laboratoire "Hypoxie et poumons", EA 2363, 93017 Bobigny, France; Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMR_S1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75013, Paris, France
| | - Florine Jeton
- Université Paris 13, Sorbonne Paris Cité, UFR SMBH, Laboratoire "Hypoxie et poumons", EA 2363, 93017 Bobigny, France
| | - Elizabeth Elliot-Portal
- Université Laval, Faculté de Médecine, Centre de Recherche Institut universitaire de cardiologie et de pneumologie de Québec, Département de Pédiatrie, Québec, QC, Canada; Molecular biology and Biotechnology Institute, Universidad Mayor de San Andres, La Paz, Bolivia
| | - Rose Tam
- Université Laval, Faculté de Médecine, Centre de Recherche Institut universitaire de cardiologie et de pneumologie de Québec, Département de Pédiatrie, Québec, QC, Canada
| | - Laurence Bodineau
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMR_S1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75013, Paris, France
| | - Nicolas Voituron
- Université Paris 13, Sorbonne Paris Cité, UFR SMBH, Laboratoire "Hypoxie et poumons", EA 2363, 93017 Bobigny, France
| | - Jorge Soliz
- Université Laval, Faculté de Médecine, Centre de Recherche Institut universitaire de cardiologie et de pneumologie de Québec, Département de Pédiatrie, Québec, QC, Canada; Molecular biology and Biotechnology Institute, Universidad Mayor de San Andres, La Paz, Bolivia.
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18
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Beltrán-Castillo S, Morgado-Valle C, Eugenín J. The Onset of the Fetal Respiratory Rhythm: An Emergent Property Triggered by Chemosensory Drive? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1015:163-192. [PMID: 29080027 DOI: 10.1007/978-3-319-62817-2_10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The mechanisms responsible for the onset of respiratory activity during fetal life are unknown. The onset of respiratory rhythm may be a consequence of the genetic program of each of the constituents of the respiratory network, so they start to interact and generate respiratory cycles when reaching a certain degree of maturation. Alternatively, generation of cycles might require the contribution of recently formed sensory inputs that will trigger oscillatory activity in the nascent respiratory neural network. If this hypothesis is true, then sensory input to the respiratory generator must be already formed and become functional before the onset of fetal respiration. In this review, we evaluate the timing of the onset of the respiratory rhythm in comparison to the appearance of receptors, neurotransmitter machinery, and afferent projections provided by two central chemoreceptive nuclei, the raphe and locus coeruleus nuclei.
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Affiliation(s)
- Sebastián Beltrán-Castillo
- Laboratorio de Sistemas Neurales, Facultad de Química y Biología, Departamento de Biología, Universidad de Santiago de Chile, USACH, PO 9170022, Santiago, Chile
| | - Consuelo Morgado-Valle
- Centro de Investigaciones Cerebrales, Universidad Veracruzana, Campus Xalapa, Berlin 7, Fracc., Monte Magno Animas, C.P. 91190, Xalapa, Veracruz, Mexico.
| | - Jaime Eugenín
- Laboratorio de Sistemas Neurales, Facultad de Química y Biología, Departamento de Biología, Universidad de Santiago de Chile, USACH, PO 9170022, Santiago, Chile.
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Iturri P, Bairam A, Soliz J. Efficient breathing at neonatal ages: A sex and Epo-dependent issue. Respir Physiol Neurobiol 2016; 245:89-97. [PMID: 28041993 DOI: 10.1016/j.resp.2016.12.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Revised: 12/02/2016] [Accepted: 12/05/2016] [Indexed: 11/29/2022]
Abstract
During postnatal life, the respiratory control system undergoes intense development and is highly responsive to stimuli emerging from the environment. In fact, interruption of breathing prevents gas exchange and results in systemic hypoxia that, if prolonged, can lead to cardio-respiratory failure or sudden infant death. Moreover, in newborns and infants, respiratory disorders related to neural control dysfunction show significant sexual dimorphism with a higher prevalence in males. To this day, the therapeutic tools available to alleviate these respiratory disorders remain limited. Furthermore, the factors explaining the sexual dimorphism in newborns and during infancy remain unknown. Erythropoietin (Epo) was originally discovered as a cytokine able to increase the production of red blood cells upon conditions of reduced oxygen availability. We now know that Epo is a cytokine also secreted by neurons and astrocytes that protects the brain during trauma or hypoxic stress in a sex dependent manner. In this novel line of research, our previous studies demonstrated at adult ages that cerebral Epo acts as a respiratory stimulant in rodents and humans. These results provided a strong rationale for exploring the role of cerebral Epo in neuronal respiratory control during postnatal development. The objective of this review is to summarize our recent findings showing that cerebral Epo is a potent sex-specific respiratory stimulant at neonatal ages. Keeping in mind that Epo is routinely and safely administrated in newborn humans for anemia and neonatal asphyxia, we predict that our research provides the basis necessary to promote the clinical use of Epo against neonatal respiratory disorders related to neural control dysfunction.
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Affiliation(s)
- Pablo Iturri
- Centre de Recherche du CHU de Québec, Pavillon St François d'Assise, Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada; Molecular Biology and Biotechnology Institute, Universidad Mayor de San Andres, La Paz, Bolivia
| | - Aida Bairam
- Centre de Recherche du CHU de Québec, Pavillon St François d'Assise, Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Jorge Soliz
- Centre de Recherche du CHU de Québec, Pavillon St François d'Assise, Département de Pédiatrie, Faculté de Médecine, Université Laval, Québec, QC, Canada; Molecular Biology and Biotechnology Institute, Universidad Mayor de San Andres, La Paz, Bolivia.
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20
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Santin JM, Hartzler LK. Environmentally induced return to juvenile-like chemosensitivity in the respiratory control system of adult bullfrog, Lithobates catesbeianus. J Physiol 2016; 594:6349-6367. [PMID: 27444338 DOI: 10.1113/jp272777] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 07/19/2016] [Indexed: 12/25/2022] Open
Abstract
KEY POINTS The degree to which developmental programmes or environmental signals determine physiological phenotypes remains a major question in physiology. Vertebrates change environments during development, confounding interpretation of the degree to which development (i.e. permanent processes) or phenotypic plasticity (i.e. reversible processes) produces phenotypes. Tadpoles mainly breathe water for gas exchange and frogs may breathe water or air depending on their environment and are, therefore, exemplary models to differentiate the degree to which life-stage vs. environmental context drives developmental phenotypes associated with neural control of lung breathing. Using isolated brainstem preparations and patch clamp electrophysiology, we demonstrate that adult bullfrogs acclimatized to water-breathing conditions do not exhibit CO2 and O2 chemosensitivity of lung breathing, similar to water-breathing tadpoles. Our results establish that phenotypes associated with developmental stage may arise from plasticity per se and suggest that a developmental trajectory coinciding with environmental change obscures origins of stage-dependent physiological phenotypes by masking plasticity. ABSTRACT An unanswered question in developmental physiology is to what extent does the environment vs. a genetic programme produce phenotypes? Developing animals inhabit different environments and switch from one to another. Thus a developmental time course overlapping with environmental change confounds interpretations as to whether development (i.e. permanent processes) or phenotypic plasticity (i.e. reversible processes) generates phenotypes. Tadpoles of the American bullfrog, Lithobates catesbeianus, breathe water at early life-stages and minimally use lungs for gas exchange. As adults, bullfrogs rely on lungs for gas exchange, but spend months per year in ice-covered ponds without lung breathing. Aquatic submergence, therefore, removes environmental pressures requiring lung breathing and enables separation of adulthood from environmental factors associated with adulthood that necessitate control of lung ventilation. To test the hypothesis that postmetamorphic respiratory control phenotypes arise through permanent developmental changes vs. reversible environmental signals, we measured respiratory-related nerve discharge in isolated brainstem preparations and action potential firing from CO2 -sensitive neurons in bullfrogs acclimatized to semi-terrestrial (air-breathing) and aquatic-overwintering (no air-breathing) habitats. We found that aquatic overwintering significantly reduced neuroventilatory responses to CO2 and O2 involved in lung breathing. Strikingly, this gas sensitivity profile reflects that of water-breathing tadpoles. We further demonstrated that aquatic overwintering reduced CO2 -induced firing responses of chemosensitive neurons. In contrast, respiratory rhythm generating processes remained adult-like after submergence. Our results establish that phenotypes associated with life-stage can arise from phenotypic plasticity per se. This provides evidence that developmental time courses coinciding with environmental changes obscure interpretations regarding origins of stage-dependent physiological phenotypes by masking plasticity.
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Affiliation(s)
- Joseph M Santin
- Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH, 45435, USA. .,Biomedical Sciences PhD Program, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH, 45435, USA.
| | - Lynn K Hartzler
- Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH, 45435, USA
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21
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Vann NC, Pham FD, Hayes JA, Kottick A, Del Negro CA. Transient Suppression of Dbx1 PreBötzinger Interneurons Disrupts Breathing in Adult Mice. PLoS One 2016; 11:e0162418. [PMID: 27611210 PMCID: PMC5017730 DOI: 10.1371/journal.pone.0162418] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 08/22/2016] [Indexed: 11/18/2022] Open
Abstract
Interneurons derived from Dbx1-expressing precursors located in the brainstem preBötzinger complex (preBötC) putatively form the core oscillator for inspiratory breathing movements. We tested this Dbx1 core hypothesis by expressing archaerhodopsin in Dbx1-derived interneurons and then transiently hyperpolarizing these neurons while measuring respiratory rhythm in vitro or breathing in vagus-intact adult mice. Transient illumination of the preBötC interrupted inspiratory rhythm in both slice preparations and sedated mice. In awake mice, light application reduced breathing frequency and prolonged the inspiratory duration. Support for the Dbx1 core hypothesis previously came from embryonic and perinatal mouse experiments, but these data suggest that Dbx1-derived preBötC interneurons are rhythmogenic in adult mice too. The neural origins of breathing behavior can be attributed to a localized and genetically well-defined interneuron population.
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Affiliation(s)
- Nikolas C. Vann
- Department of Applied Science, The College of William and Mary, Williamsburg, Virginia, United States of America
| | - Francis D. Pham
- Department of Applied Science, The College of William and Mary, Williamsburg, Virginia, United States of America
| | - John A. Hayes
- Department of Applied Science, The College of William and Mary, Williamsburg, Virginia, United States of America
| | - Andrew Kottick
- Department of Applied Science, The College of William and Mary, Williamsburg, Virginia, United States of America
| | - Christopher A. Del Negro
- Department of Applied Science, The College of William and Mary, Williamsburg, Virginia, United States of America
- * E-mail:
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22
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Lavezzi AM, Ferrero S, Matturri L, Roncati L, Pusiol T. Developmental neuropathology of brainstem respiratory centers in unexplained stillbirth: What's the meaning? Int J Dev Neurosci 2016; 53:99-106. [DOI: 10.1016/j.ijdevneu.2016.06.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 06/24/2016] [Accepted: 06/24/2016] [Indexed: 01/28/2023] Open
Affiliation(s)
- Anna M. Lavezzi
- “Lino Rossi” Research Center for the Study and Prevention of Unexpected Perinatal Death and SIDSDepartment of Biomedical, Surgical and Dental SciencesUniversity of MilanItaly
| | - Stefano Ferrero
- “Lino Rossi” Research Center for the Study and Prevention of Unexpected Perinatal Death and SIDSDepartment of Biomedical, Surgical and Dental SciencesUniversity of MilanItaly
- Division of Pathology, Fondazione IRCCS Ca' GrandaOspedale Maggiore PoliclinicoMilanItaly
- Department of Biomedical, Surgical and Dental SciencesUniversity of MilanMilanItaly
| | - Luigi Matturri
- “Lino Rossi” Research Center for the Study and Prevention of Unexpected Perinatal Death and SIDSDepartment of Biomedical, Surgical and Dental SciencesUniversity of MilanItaly
| | - Luca Roncati
- Institute of PathologyHospital of Rovereto (Trento)Italy
- Department of Diagnostic and Clinical Medicine and of Public Health, Section of PathologyUniversity of Modena and Reggio EmiliaPoliclinico HospitalModenaItaly
| | - Teresa Pusiol
- Institute of PathologyHospital of Rovereto (Trento)Italy
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Abstract
From birth, animals should possess functional machinery to appropriately regulate its respiration. This machinery has to detect the available oxygen quantity in order to efficiently modulate breathing movements in accordance with body requirements. The chemosensitivity process responsible for this detection is known to be mainly performed by carotid bodies. However, pulmonary neuroendocrine cells, which are mainly gathered in neuroepithelial bodies, also present the capability to exert chemosensitivity. The goal of this article is to put in perspective the potential complementarity in the activity of these two peripheral chemosensors in the context of neonatal oxygen chemosensitivity.
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Affiliation(s)
- Céline Caravagna
- Institut de Neurosciences de la Timone-Equipe IMAPATH, CERIMED, UMR 7289 CNRS & Aix-Marseille Université, 27 Boulevard Jean Moulin,13385, Marseille Cedex 05, France.
| | - Tommy Seaborn
- Faculté de Médecine, Université Laval, Pavillon Ferdinand-Vandry, Room 4645-A,1050, Avenue de la Médecine, Quebec, QC, G1V 0A6, Canada
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Developmental plasticity of phrenic motoneuron and diaphragm properties with the inception of inspiratory drive transmission in utero. Exp Neurol 2016; 287:137-143. [PMID: 27181410 DOI: 10.1016/j.expneurol.2016.05.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 05/06/2016] [Accepted: 05/11/2016] [Indexed: 11/23/2022]
Abstract
The review outlines data consistent with the hypothesis that inspiratory drive transmission that generates fetal breathing movements (FBMs) is essential for the developmental plasticity of phrenic motoneurons (PMNs) and diaphragm musculature prior to birth. A systematic examination during the perinatal period demonstrated a very marked transformation of PMN and diaphragm properties coinciding with the onset and strengthening of inspiratory drive and FBMs in utero. This included studies of age-dependent changes of: i) morphology, neuronal coupling, passive and electrophysiological properties of PMNs; ii) rhythmic inspiratory activity in vitro; iii) FBMs generated in vivo detected by ultrasonography; iv) contractile and end-plate potential properties of diaphragm musculature. We also propose how the hypothesis can be further evaluated with studies of perinatal hypoglossal motoneuron-tongue musculature and the use of Dbx1 null mice that provide an experimental model lacking descending inspiratory drive transmission in utero.
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25
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Rousseau JP, Caravagna C. Electrophysiology on Isolated Brainstem-spinal Cord Preparations from Newborn Rodents Allows Neural Respiratory Network Output Recording. J Vis Exp 2015. [PMID: 26649567 DOI: 10.3791/53071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
While it is well known that the central respiratory drive is located in the brainstem, several aspects of its basic function, development, and response to stimuli remain to be fully understood. To overcome the difficulty of accessing the brainstem in the whole animal, isolation of the brainstem and part of the spinal cord is performed. This preparation is maintained in artificial cerebro-spinal fluid where gases, concentrations, and temperature are controlled and monitored. The output signal from the respiratory network is recorded by a suction electrode placed on the fourth ventral root. In this manner, stimuli can be directly applied onto the brainstem, and the effect can be recorded directly. The signal recorded is linked to the inspiratory signal sent to the diaphragm via the phrenic nerve, and can be described as bursts (around 8 bursts per minute). Analysis of these bursts (frequency, amplitude, length, and area under the curve) allows precise characterization of the stimulus effect on the respiratory network. The main limitation of this method is the viability of the preparation beyond the early post-natal stages. Thus, this method greatly focuses on the study of the whole network without the peripheral inputs in the newborn rat.
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Caravagna C, Schneider Gasser EM, Ballot O, Joseph V, Soliz J. Chronic overexpression of cerebral Epo improves the ventilatory response to acute hypoxia during the postnatal development. Int J Dev Neurosci 2015; 44:84-91. [DOI: 10.1016/j.ijdevneu.2015.06.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 06/01/2015] [Accepted: 06/04/2015] [Indexed: 10/23/2022] Open
Affiliation(s)
- Céline Caravagna
- Department of PediatricsLaval University Center de Recherche du Center Hospitalier Universitaire (CHU) de Québec, Hôpital St‐François d'Assise10 Rue de l'EspinayQuébecQCG1L 3L5Canada
| | - Edith M. Schneider Gasser
- Institute of Veterinary PhysiologyVetsuisse‐Faculty University of ZurichWinterthurerstrasse 260CH‐8057ZurichSwitzerland
| | - Orlane Ballot
- Department of PediatricsLaval University Center de Recherche du Center Hospitalier Universitaire (CHU) de Québec, Hôpital St‐François d'Assise10 Rue de l'EspinayQuébecQCG1L 3L5Canada
| | - Vincent Joseph
- Department of PediatricsLaval University Center de Recherche du Center Hospitalier Universitaire (CHU) de Québec, Hôpital St‐François d'Assise10 Rue de l'EspinayQuébecQCG1L 3L5Canada
| | - Jorge Soliz
- Department of PediatricsLaval University Center de Recherche du Center Hospitalier Universitaire (CHU) de Québec, Hôpital St‐François d'Assise10 Rue de l'EspinayQuébecQCG1L 3L5Canada
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PI3K and MEK1/2 molecular pathways are involved in the erythropoietin-mediated regulation of the central respiratory command. Respir Physiol Neurobiol 2015; 206:36-40. [DOI: 10.1016/j.resp.2014.11.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/01/2014] [Accepted: 11/16/2014] [Indexed: 11/21/2022]
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Lavezzi AM, Corna MF, Matturri L. Disruption of the brain-derived neurotrophic factor (BDNF) immunoreactivity in the human Kölliker-Fuse nucleus in victims of unexplained fetal and infant death. Front Hum Neurosci 2014; 8:648. [PMID: 25237300 PMCID: PMC4154391 DOI: 10.3389/fnhum.2014.00648] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 08/04/2014] [Indexed: 12/11/2022] Open
Abstract
Experimental studies have demonstrated that the neurotrophin brain-derived neutrophic factor (BDNF) is required for the appropriate development of the central respiratory network, a neuronal complex in the brainstem of vital importance to sustaining life. The pontine Kölliker-Fuse nucleus (KFN) is a fundamental component of this circuitry with strong implications in the pre- and postnatal breathing control. This study provides detailed account for the cytoarchitecture, the physiology and the BDNF behavior of the human KFN in perinatal age. We applied immunohistochemistry in formalin-fixed and paraffin-embedded brainstem samples (from 45 fetuses and newborns died of both known and unknown causes), to analyze BDNF, gliosis and apoptosis patterns of manifestation. The KFN showed clear signs of developmental immaturity, prevalently associated to BDNF altered expression, in high percentages of sudden intrauterine unexplained death syndrome (SIUDS) and sudden infant death syndrome (SIDS) victims. Our results indicate that BDNF pathway dysfunctions can derange the normal KFN development so preventing the breathing control in the sudden perinatal death. The data presented here are also relevant to a better understanding of how the BDNF expression in the KFN can be involved in several human respiratory pathologies such as the Rett's and the congenital central hypoventilation syndromes.
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Affiliation(s)
- Anna M Lavezzi
- "Lino Rossi" Research Center for the Study and Prevention of Unexpected Perinatal Death and SIDS Department of Biomedical, Surgical and Dental Sciences, University of Milan Milan, Italy
| | - Melissa F Corna
- "Lino Rossi" Research Center for the Study and Prevention of Unexpected Perinatal Death and SIDS Department of Biomedical, Surgical and Dental Sciences, University of Milan Milan, Italy
| | - Luigi Matturri
- "Lino Rossi" Research Center for the Study and Prevention of Unexpected Perinatal Death and SIDS Department of Biomedical, Surgical and Dental Sciences, University of Milan Milan, Italy
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Delhaes F, Fournier S, Tolsa JF, Peyter AC, Bairam A, Kinkead R. Consequences of gestational stress on GABAergic modulation of respiratory activity in developing newborn pups. Respir Physiol Neurobiol 2014; 200:72-9. [DOI: 10.1016/j.resp.2014.05.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 05/21/2014] [Accepted: 05/23/2014] [Indexed: 12/13/2022]
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Caravagna C, Kinkead R, Soliz J. Post-natal hypoxic activity of the central respiratory command is improved in transgenic mice overexpressing Epo in the brain. Respir Physiol Neurobiol 2014; 200:64-71. [PMID: 24914467 DOI: 10.1016/j.resp.2014.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 06/02/2014] [Accepted: 06/03/2014] [Indexed: 11/29/2022]
Abstract
Previous studies indicated that erythropoietin modulates central respiratory command in mice. Specifically, a one-hour incubation of the brainstems with erythropoietin attenuates hypoxia-induced central respiratory depression. Here, using transgenic mice constitutively overexpressing erythropoietin specifically in the brain (Tg21), we investigated the effect of chronic erythropoietin stimulation on central respiratory command activity during post-natal development. In vitro brainstem-spinal cord preparations from mice at 0 (P0) or 3 days of age (P3) were used to record the fictive inspiratory activity from the C4 ventral root. Our results show that erythropoietin already stimulates the hypoxic burst frequency at P0, and at P3, erythropoietin effectively stimulates the hypoxic burst frequency and amplitude. Because the maturation of the central respiratory command in mice is characterized by a decrease in the burst frequency with age, our results also suggest that erythropoietin accelerates the maturation of the newborn respiratory network and its response to hypoxia.
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Affiliation(s)
- Céline Caravagna
- Department of Pediatrics, Laval University, Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec, Hôpital St-François d'Assise, 10 Rue de l'Espinay, Québec, QC G1L 3L5, Canada.
| | - Richard Kinkead
- Department of Pediatrics, Laval University, Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec, Hôpital St-François d'Assise, 10 Rue de l'Espinay, Québec, QC G1L 3L5, Canada.
| | - Jorge Soliz
- Department of Pediatrics, Laval University, Centre de Recherche du Centre Hospitalier Universitaire (CHU) de Québec, Hôpital St-François d'Assise, 10 Rue de l'Espinay, Québec, QC G1L 3L5, Canada.
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Abstract
Breathing movements have been demonstrated in the fetuses of every mammalian species investigated and are a critical component of normal fetal development. The classic sheep preparations instrumented for chronic fetal monitoring determined that fetal breathing movements (FBMs) occur in aggregates interspersed with long periods of quiescence that are strongly associated with neurophysiological state. The fetal sheep model also provided data regarding the neurochemical modulation of behavioral state and FBMs under a variety of in utero conditions. Subsequently, in vitro rodent models have been developed to advance our understanding of cellular, synaptic, network, and more detailed neuropharmacological aspects of perinatal respiratory neural control. This includes the ontogeny of the inspiratory rhythm generating center, the preBötzinger complex (preBötC), and the anatomical and functional development of phrenic motoneurons (PMNs) and diaphragm during the perinatal period. A variety of newborn animal models and studies of human infants have provided insights into age-dependent changes in state-dependent respiratory control, responses to hypoxia/hypercapnia and respiratory pathologies.
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Affiliation(s)
- John J Greer
- Department of Physiology, Centre for Neuroscience, Women and Children Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.
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Abstract
Pontine respiratory nuclei provide synaptic input to medullary rhythmogenic circuits to shape and adapt the breathing pattern. An understanding of this statement depends on appreciating breathing as a behavior, rather than a stereotypic rhythm. In this review, we focus on the pontine-mediated inspiratory off-switch (IOS) associated with postinspiratory glottal constriction. Further, IOS is examined in the context of pontine regulation of glottal resistance in response to multimodal sensory inputs and higher commands, which in turn rules timing, duration, and patterning of respiratory airflow. In addition, network plasticity in respiratory control emerges during the development of the pons. Synaptic plasticity is required for dynamic and efficient modulation of the expiratory breathing pattern to cope with rapid changes from eupneic to adaptive breathing linked to exploratory (foraging and sniffing) and expulsive (vocalizing, coughing, sneezing, and retching) behaviors, as well as conveyance of basic emotions. The speed and complexity of changes in the breathing pattern of behaving animals implies that "learning to breathe" is necessary to adjust to changing internal and external states to maintain homeostasis and survival.
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Affiliation(s)
- Mathias Dutschmann
- Florey Neurosciences Institutes, University of Melbourne, Victoria, Australia.
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Ramirez JM, Doi A, Garcia AJ, Elsen FP, Koch H, Wei AD. The cellular building blocks of breathing. Compr Physiol 2013; 2:2683-731. [PMID: 23720262 DOI: 10.1002/cphy.c110033] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Respiratory brainstem neurons fulfill critical roles in controlling breathing: they generate the activity patterns for breathing and contribute to various sensory responses including changes in O2 and CO2. These complex sensorimotor tasks depend on the dynamic interplay between numerous cellular building blocks that consist of voltage-, calcium-, and ATP-dependent ionic conductances, various ionotropic and metabotropic synaptic mechanisms, as well as neuromodulators acting on G-protein coupled receptors and second messenger systems. As described in this review, the sensorimotor responses of the respiratory network emerge through the state-dependent integration of all these building blocks. There is no known respiratory function that involves only a small number of intrinsic, synaptic, or modulatory properties. Because of the complex integration of numerous intrinsic, synaptic, and modulatory mechanisms, the respiratory network is capable of continuously adapting to changes in the external and internal environment, which makes breathing one of the most integrated behaviors. Not surprisingly, inspiration is critical not only in the control of ventilation, but also in the context of "inspiring behaviors" such as arousal of the mind and even creativity. Far-reaching implications apply also to the underlying network mechanisms, as lessons learned from the respiratory network apply to network functions in general.
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Affiliation(s)
- J M Ramirez
- Center for Integrative Brain Research, Seattle Children's Research Institut, Seattle, Washington, USA.
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Berner J, Shvarev Y, Zimmer A, Wickstrom R. Hypoxic ventilatory response in Tac1-/- neonatal mice following exposure to opioids. J Appl Physiol (1985) 2012; 113:1718-26. [PMID: 23065762 DOI: 10.1152/japplphysiol.00188.2012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Morphine is the dominating analgetic drug used in neonates, but opioid-induced respiratory depression limits its therapeutic use. In this study, we examined acute morphine effects on respiration during intermittent hypoxia in newborn Tac1 gene knockout mice (Tac1-/-) lacking substance P and neurokinin A. In vivo, plethysmography revealed a blunted hypoxic ventilatory response (HVR) in Tac1-/- mice. Morphine (10 mg/kg) depressed the HVR in wild-type animals through an effect on respiratory frequency, whereas it increased tidal volumes in Tac1-/- during hypoxia, resulting in increased minute ventilation. Apneas were reduced during the first hypoxic episode in both morphine-exposed groups, but were restored subsequently in Tac1-/- mice. Morphine did not affect ventilation or apnea prevalence during baseline conditions. In vitro, morphine (50 nM) had no impact on anoxic response of brain stem preparations of either strain. In contrast, it suppressed the inspiratory rhythm during normoxia and potentiated development of posthypoxic neuronal arrest, especially in Tac1-/-. Thus this phenotype has a higher sensitivity to the depressive effects of morphine on inspiratory rhythm generation, but morphine does not modify the reactivity to oxygen deprivation. In conclusion, although Tac1-/- mice are similar to wild-type animals during normoxia, they differed by displaying a reversed pattern with an improved HVR during intermittent hypoxia both in vivo and in vitro. These data suggest that opioids and the substance P-ergic system interact in the HVR, and that reducing the activity in the tachykinin system may alter the respiratory effects of opioid treatment in newborns.
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Affiliation(s)
- J Berner
- Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden.
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35
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Kuznetsov SV, Dmitrieva LE, Sizonov VA. Cardiac, respiratory, and motor activity in norm and after activation of catecholaminergic systems in newborn rat pups. J EVOL BIOCHEM PHYS+ 2012. [DOI: 10.1134/s002209301204007x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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36
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Timofeeva OP, Vdovichenko ND, Kuznetsov SV. Effect of change in activity level of catecholaminergic systems on motor, respiratory, and cardiac activities in fetal rats. J EVOL BIOCHEM PHYS+ 2012. [DOI: 10.1134/s0022093012030085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Khemiri H, Seaborn T, Gestreau C, Soliz J. Erythropoietin and its antagonist regulate hypoxic fictive breathing in newborn mice. Respir Physiol Neurobiol 2012; 183:115-21. [PMID: 22684041 DOI: 10.1016/j.resp.2012.05.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 05/29/2012] [Accepted: 05/30/2012] [Indexed: 10/28/2022]
Abstract
Clinical use of erythropoietin in adult and newborn patients has revealed its involvement in neuroprotection, neurogenesis, and angiogenesis. More recently, we showed in adult mouse, that brain erythropoietin interacts with the major brainstem centers associated with respiration to enhance the ventilatory response to acute and chronic conditions of physiological hypoxia (e.g., as occurring at high altitude). However, whether brain erythropoietin is involved in breathing regulation in newborns remains unknown. In this study, en bloc brainstem-spinal cord preparations were obtained from mice at postnatal day 4. After various periods (30, 60, or 90 min) of incubation with 0, 25, or 250 U of erythropoietin, preparations were superfused with artificial cerebrospinal fluid bubbled with normoxic or hypoxic gas mixtures. The electrophysiological fictive breathing produced by axons at the C4 ventral root was next recorded. Our results show that erythropoietin attenuates the hypoxia-mediated decrease of the central respiratory activity and improves post-hypoxic recovery. Additional analysis revealed that the soluble erythropoietin receptor (the endogenous erythropoietin antagonist) dramatically decreases neural hypoxic respiratory activity, confirming the specific erythropoietin effect on respiratory drive. These results imply that erythropoietin exerts main modulation and maintenance of respiratory motor output during hypoxic and post-hypoxic challenges in 4-days old mice.
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Affiliation(s)
- Hanan Khemiri
- Départment de Pédiatrie, Centre de Recherche de l'Hôpital St-François d'Assise (CR-SFA), Centre Hospitalier Universitaire de Québec (CHUQ), Faculté de Médecine, Université Laval, Québec, QC, Canada.
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Voituron N, Hilaire G, Quintin L. Dexmedetomidine and clonidine induce long-lasting activation of the respiratory rhythm generator of neonatal mice: possible implication for critical care. Respir Physiol Neurobiol 2011; 180:132-40. [PMID: 22108092 DOI: 10.1016/j.resp.2011.11.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 11/05/2011] [Accepted: 11/05/2011] [Indexed: 11/19/2022]
Abstract
Dexmedetomidine and clonidine are alpha-2 adrenoceptor agonists increasingly used in the critical care unit as sedative agents for their benzodiazepine-sparing effects and their limited depressing effect on breathing. However adverse effects on breathing have been also reported with alpha-2 adrenoceptor agonists and their central effects on the respiratory rhythm generator are poorly known. We therefore examined the effects of dexmedetomidine, clonidine, the alpha-2 adrenoceptor antagonist yohimbine and the benzodiazepine midazolam on the activity of the isolated respiratory rhythm generator of neonatal mice using medullary preparations where the respiratory rhythm generator continued to function in vitro. For the first time, we showed that 5min bath applications of dexmedetomidine or clonidine activated the respiratory rhythm generator for periods over than 30min. Second, we showed that the long-lasting effect of dexmedetomidine implicated receptors other than alpha-2 adrenoceptors as it persisted after their blockade with yohimbine. Third, we reported that 5min bath applications of the benzodiazepine midazolam significantly depressed the respiratory rhythm generator, and that this depression was prevented by pre-treatment with either dexmedetomidine or clonidine. Although further experiments are still required to identify the mechanisms through which dexmedetomidine and clonidine activate the respiratory rhythm generator, our current in vitro results in neonatal mice support the use of dexmedetomidine and clonidine in the critical care unit.
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Affiliation(s)
- Nicolas Voituron
- Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille, Unité Mixte de Recherche 6231 Centre National Recherche Scientifique/Université Aix-Marseille II et III, Team mp3-Respiration, Faculté Saint-Jérôme (case 362), 13397 Marseille Cedex 20, France
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Bursian AV. Organization of endogenous rhythms of motor functions (To the 100-Anniversary of A.V. Voino-Yasenetskii). J EVOL BIOCHEM PHYS+ 2010. [DOI: 10.1134/s0022093009060039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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40
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Biancardi V, da Silva LT, Bícego KC, Gargaglioni LH. Role of Locus coeruleus noradrenergic neurons in cardiorespiratory and thermal control during hypoxia. Respir Physiol Neurobiol 2010; 170:150-6. [DOI: 10.1016/j.resp.2009.12.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2009] [Revised: 12/11/2009] [Accepted: 12/14/2009] [Indexed: 12/29/2022]
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Tripartite purinergic modulation of central respiratory networks during perinatal development: the influence of ATP, ectonucleotidases, and ATP metabolites. J Neurosci 2010; 29:14713-25. [PMID: 19940166 DOI: 10.1523/jneurosci.2660-09.2009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
ATP released during hypoxia from the ventrolateral medulla activates purinergic receptors (P2Rs) to attenuate the secondary hypoxic depression of breathing by a mechanism that likely involves a P2Y(1)R-mediated excitation of preBötzinger complex (preBötC) inspiratory rhythm-generating networks. In this study, we used rhythmically active in vitro preparations from embryonic and postnatal rats and ATP microinjection into the rostral ventral respiratory group (rVRG)/preBötC to reveal that these networks are sensitive to ATP when rhythm emerges at embryonic day 17 (E17). The peak frequency elicited by ATP at E19 and postnatally was the same ( approximately 45 bursts/min), but relative sensitivity was threefold greater at E19, reflecting a lower baseline frequency (5.6 +/- 0.9 vs 19.0 +/- 1.3 bursts/min). Combining microinjection techniques with ATP biosensors revealed that ATP concentration in the rVRG/preBötC falls rapidly as a result of active processes and closely correlates with inspiratory frequency. A phosphate assay established that preBötC-containing tissue punches degrade ATP at rates that increase perinatally. Thus, the agonist profile [ATP/ADP/adenosine (ADO)] produced after ATP release in the rVRG/preBötC will change perinatally. Electrophysiology further established that the ATP metabolite ADP is excitatory and that, in fetal but not postnatal animals, ADO at A(1) receptors exerts a tonic depressive action on rhythm, whereas A(1) antagonists extend the excitatory action of ATP on inspiratory rhythm. These data demonstrate that ATP is a potent excitatory modulator of the rVRG/preBötC inspiratory network from the time it becomes active and that ATP actions are determined by a dynamic interaction between the actions of ATP at P2 receptors, ectonucleotidases that degrade ATP, and ATP metabolites on P2Y and P1 receptors.
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Embryonic emergence of the respiratory rhythm generator. Respir Physiol Neurobiol 2009; 168:86-91. [DOI: 10.1016/j.resp.2009.06.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 06/19/2009] [Accepted: 06/20/2009] [Indexed: 11/20/2022]
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Antenatal environmental stress and maturation of the breathing control, experimental data. Respir Physiol Neurobiol 2009; 168:92-100. [PMID: 19427414 DOI: 10.1016/j.resp.2009.04.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 04/27/2009] [Accepted: 04/30/2009] [Indexed: 11/24/2022]
Abstract
The nervous respiratory system undergoes postnatal maturation and yet still must be functional at birth. Any antenatal suboptimal environment could upset either its building prenatally and/or its maturation after birth. Here, we would like to briefly summarize some of the major stresses leading to clinical postnatal respiratory dysfunction that can occur during pregnancy, we then relate them to experimental models that have been developed in order to better understand the underlying mechanisms implicated in the respiratory dysfunctions observed in neonatal care units. Four sections are aimed to review our current knowledge based on experimental data. The first will deal with the metabolic factors such as oxygen and glucose, the second with consumption of psychotropic substances (nicotine, cocaine, alcohol, morphine, cannabis and caffeine), the third with psychoactive molecules commonly consumed by pregnant women within a therapeutic context and/or delivered to premature neonates in critical care units (benzodiazepine, caffeine). In the fourth section, we take into account care protocols involving extended maternal-infant separation due to isolation in incubators. The effects of this stress potentially adds to those previously described.
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Viemari JC. Noradrenergic modulation of the respiratory neural network. Respir Physiol Neurobiol 2009; 164:123-30. [PMID: 18634907 DOI: 10.1016/j.resp.2008.06.016] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Revised: 06/17/2008] [Accepted: 06/18/2008] [Indexed: 10/21/2022]
Abstract
Noradrenergic dysregulation has been reported in human pathologies affecting the control of breathing, such as sudden infant death syndrome, congenital central hypoventilation syndrome and Rett syndrome. Noradrenergic neurons, located predominantly in pontine nuclei, are among the earliest to arise within the hindbrain and play an essential role in the maturation of the respiratory network. Noradrenergic neurons also play a major role in the modulation of the respiratory motor pattern from birth through adulthood. The critical importance of this signaling system in respiratory control is illustrated by the severe respiratory disturbances associated with gene mutations affecting noradrenergic neurons (Phox2 and Mecp2). Here, the role of catecholaminergic pontine nuclei in the control of breathing, the cellular effects of norepinephrine on the respiratory network and the pathological consequence to breathing of abnormalities in this signaling system will be discussed.
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Affiliation(s)
- Jean-Charles Viemari
- Laboratoire Plasticité et Physio-Pathologie de la Motricité (P3M), UMR 6196-CNRS, Aix-Marseille Université, CNRS, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
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45
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Corcoran AE, Milsom WK. Maturational changes in pontine and medullary alpha-adrenoceptor influences on respiratory rhythm generation in neonatal rats. Respir Physiol Neurobiol 2008; 165:195-201. [PMID: 19110076 DOI: 10.1016/j.resp.2008.11.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Revised: 11/03/2008] [Accepted: 11/29/2008] [Indexed: 10/21/2022]
Abstract
We examined developmental changes in alpha-adrenoceptor influences and descending pontine inputs on the medullary respiratory network in the neonatal rat in vitro brainstem-spinal cord preparation. Using a split bath preparation to isolate the pons from the medulla, antagonists for alpha1 and alpha2 adrenoreceptors were applied to only the medulla at postnatal days 0, 2 and 4, before and after transection of the pons. Blocking alpha1 and alpha2 receptors in the medulla in the absence of a pons reduced burst frequency at all ages with a more pronounced effect in younger animals. At all ages the presence of a pons diminished the effect of blocking alpha2 receptors in the medulla and eliminated the effect of blocking alpha1 receptors. These results indicate that there is a tonic release of catecholamines within the medulla that is under influence from the pons. Additionally, transection experiments indicated that during development, the net influence of the pons changed from one of excitation to one of inhibition.
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Affiliation(s)
- Andrea E Corcoran
- Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA.
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46
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Berner J, Ringstedt T, Brodin E, Hökfelt T, Lagercrantz H, Wickström R. Prenatal exposure to nicotine affects substance p and preprotachykinin-A mRNA levels in newborn rat. Pediatr Res 2008; 64:621-4. [PMID: 18679163 DOI: 10.1203/pdr.0b013e318186e5f5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Prenatal nicotine exposure influences neuronal development including effects on several neurotransmitter systems. It also attenuates the ventilatory response to hypoxia, known to require a functional substance P-ergic system. Previous studies have shown that nicotine increases the risk for sudden infant death syndrome (SIDS) by 4-fold, and that SIDS-victims have elevated brainstem levels of substance P. We, therefore, studied the effect of prenatal nicotine exposure on the levels of substance P-like immunoreactivity by RIA in the brain in newborn rat pups. The expression of the substance P precursor preprotachykinin A mRNA was also determined by real-time reverse transcriptase-polymerase chain reaction in carotid body, in petrosal/jugular and trigeminal ganglia, in cervical and lumbar dorsal root ganglia, and in the brainstem. We found that prenatal nicotine exposure increased levels of substance P-like immunoreactivity in the brainstem without changing levels in other parts of the brain or in the adrenals. Furthermore, mRNA levels were increased in the carotid bodies and in the petrosal ganglia, in contrast to the decreased levels in the cervical dorsal root ganglia. We conclude that nicotine causes alterations in the substance P-ergic system in the brainstem, possibly linked to the increased risk for SIDS after prenatal nicotine exposure.
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Affiliation(s)
- Jonas Berner
- Department of Woman and Child Health, Karolinska Institutet, 171 77 Stockholm, Sweden.
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Fong AY, Corcoran AE, Zimmer MB, Andrade DV, Milsom WK. Respiratory rhythm of brainstem-spinal cord preparations: Effects of maturation, age, mass and oxygenation. Respir Physiol Neurobiol 2008; 164:429-40. [PMID: 18948229 DOI: 10.1016/j.resp.2008.09.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Revised: 08/28/2008] [Accepted: 09/12/2008] [Indexed: 10/21/2022]
Abstract
We examined the effect of age, mass and the presence of the pons on the longevity (length of time spontaneous respiratory-related activity is produced) of brainstem-spinal cord preparations of neonatal rodents (rats and hamsters) and the level of oxygenation in the medulla respiratory network in these preparations. We found the longevity of the preparations from both species decreased with increasing postnatal age. Physical removal of the pons increased respiratory frequency and the longevity of the preparation. However, tissue oxygenation at the level of the medullary respiratory network was not affected by removal of the pons or increasing postnatal age (up to postnatal day 4). Taken together, these data suggest that the effect of removing the pons on respiratory frequency and the longevity of brainstem-spinal cord preparations with increasing postnatal age are primarily due to postnatal development and appear to be unrelated to mass or changes in levels of tissue oxygenation.
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Affiliation(s)
- Angelina Y Fong
- Department of Zoology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
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48
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Marin-Burgin A, Kristan WB, French KA. From synapses to behavior: development of a sensory-motor circuit in the leech. Dev Neurobiol 2008; 68:779-87. [PMID: 18383550 DOI: 10.1002/dneu.20551] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The development of neuronal circuits has been advanced greatly by the use of imaging techniques that reveal the activity of neurons during the period when they are constructing synapses and forming circuits. This review focuses on experiments performed in leech embryos to characterize the development of a neuronal circuit that produces a simple segmental behavior called "local bending." The experiments combined electrophysiology, anatomy, and FRET-based voltage-sensitive dyes (VSDs). The VSDs offered two major advantages in these experiments: they allowed us to record simultaneously the activity of many neurons, and unlike other imaging techniques, they revealed inhibition as well as excitation. The results indicated that connections within the circuit are formed in a predictable sequence: initially neurons in the circuit are connected by electrical synapses, forming a network that itself generates an embryonic behavior and prefigures the adult circuit; later chemical synapses, including inhibitory connections, appear, "sculpting" the circuit to generate a different, mature behavior. In this developmental process, some of the electrical connections are completely replaced by chemical synapses, others are maintained into adulthood, and still others persist and share their targets with chemical synaptic connections.
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Affiliation(s)
- Antonia Marin-Burgin
- Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093, USA.
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Fournier S, Kinkead R. Role of pontine neurons in central O(2) chemoreflex during development in bullfrogs (Lithobates catesbeiana). Neuroscience 2008; 155:983-96. [PMID: 18590803 DOI: 10.1016/j.neuroscience.2008.05.044] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Revised: 05/20/2008] [Accepted: 05/26/2008] [Indexed: 11/25/2022]
Abstract
The present study used an in vitro brainstem preparation from pre-metamorphic tadpoles and adult bullfrogs (Lithobates catesbeiana) to understand the neural mechanisms associated with central O(2) chemosensitivity and its maturation. In this species, brainstem hypoxia increases fictive lung ventilation in tadpoles but decreases in adults. Previous studies have shown that alpha(1)-adrenoceptor inactivation prevents these responses, suggesting that noradrenergic neurons are involved. We first tested the hypothesis that the pons (which includes noradrenergic neurons from the locus coeruleus; LC) plays a role in the lung burst frequency response to central hypoxia by comparing the effects of brainstem transection at the LC level between pre-metamorphic tadpoles and adults. Data show that brainstem transection prevents the lung burst frequency response in both stage groups. During development, the progressive decrease in the Na(+)/K(+)/Cl(-) co-transporter NKCC1 contributes to the maturation of neural networks. Because NKCC1 becomes activated during hypoxia, we then tested the hypothesis that NKCC1 contributes to maturation of the central O(2) chemoreflex. Double labeling experiments showed that the proportion of tyrosine hydroxylase positive neurons expressing NKCC1 in the LC decreases during development. Inactivation of NKCC1 with bumetanide bath application reversed the lung burst response to hypoxia in tadpoles. Bumetanide inhibited the response in adults. These data indicate that a structure within the pons (potentially the LC) is necessary to the central hypoxic chemoreflex and demonstrate that NKCC1 plays a role in central O(2) chemosensitivity and its maturation in this species.
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Affiliation(s)
- S Fournier
- Department of Pediatrics, Université Laval, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec City, QC, Canada
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Zanella S, Barthelemy M, Muscatelli F, Hilaire G. Necdin gene, respiratory disturbances and Prader-Willi syndrome. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 605:159-64. [PMID: 18085265 DOI: 10.1007/978-0-387-73693-8_28] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Prader-Willi Syndrome (PWS) is a complex neurogenetic disease with various symptoms, including breathing deficits and possible alteration of serotonin (5HT) metabolism. As PWS results from the absence of paternal expression of several imprinted genes among which NECDIN (Ndn), we examined whether Ndn deficiency in mice induced breathing and 5HT deficits. In vivo, Ndn-deficient mice (Ndn-/-) had irregular breathing, severe apneas and blunted respiratory response to hypoxia. In vitro, medullary preparations from Ndn-/- neonates produced a respiratory-like rhythm that was highly irregular, frequently interrupted and abnormally regulated by central hypoxia. In wild type (wt) and Ndn-/- neonates, immunohistofluorescence and biochemistry revealed that medullary 5HT neurons expressed Ndn in wt and that the medulla contained abnormally high levels of 5HT in Ndn-/-. Thus, our preliminary results fully confirm a primary role of Ndn in PWS, revealing that Ndn-deficiency in mice induces respiratory and 5HT alterations reminiscent of PWS.
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Affiliation(s)
- Sébastien Zanella
- CNRS, UMR 6153, 280 boulevard Sainte Marguerite, 13009 Marseille, France
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