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Abstract
The carotid body (CB) is a bilateral arterial chemoreceptor located in the carotid artery bifurcation with an essential role in cardiorespiratory homeostasis. It is composed of highly perfused cell clusters, or glomeruli, innervated by sensory fibers. Glomus cells, the most abundant in each glomerulus, are neuron-like multimodal sensory elements able to detect and integrate changes in several physical and chemical parameters of the blood, in particular O2 tension, CO2 and pH, as well as glucose, lactate, or blood flow. Activation of glomus cells (e.g., during hypoxia or hypercapnia) stimulates the afferent fibers which impinge on brainstem neurons to elicit rapid compensatory responses (hyperventilation and sympathetic activation). This chapter presents an updated view of the structural organization of the CB and the mechanisms underlying the chemosensory responses of glomus cells, with special emphasis on the molecular processes responsible for acute O2 sensing. The properties of the glomus cell-sensory fiber synapse as well as the organization of CB output are discussed. The chapter includes the description of recently discovered CB stem cells and progenitor cells, and their role in CB growth during acclimatization to hypoxemia. Finally, the participation of the CB in the mechanisms of disease is briefly discussed.
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Affiliation(s)
- José López-Barneo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Sevilla, Seville, Spain; Biomedical Research Center for Neurodegenerative Diseases (CIBERNED), Madrid, Spain.
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Analysis of Spatial and Temporal Distribution of Purinergic P2 Receptors in the Mouse Hippocampus. Int J Mol Sci 2021; 22:ijms22158078. [PMID: 34360844 PMCID: PMC8348931 DOI: 10.3390/ijms22158078] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/12/2021] [Accepted: 07/22/2021] [Indexed: 01/08/2023] Open
Abstract
ATP and other nucleotides are important glio-/neurotransmitters in the central nervous system. They bind to purinergic P2X and P2Y receptors that are ubiquitously expressed in various brain regions modulating various physiological and pathophysiological processes. P2X receptors are ligand-gated ion channels mediating excitatory postsynaptic responses whereas P2Y receptors are G protein-coupled receptors mediating slow synaptic transmission. A variety of P2X and P2Y subtypes with distinct neuroanatomical localization provide the basis for a high diversity in their function. There is increasing evidence that P2 receptor signaling plays a prominent role in learning and memory and thus, in hippocampal neuronal plasticity. Learning and memory are time-of-day-dependent. Moreover, extracellular ATP shows a diurnal rhythm in rodents. However, it is not known whether P2 receptors have a temporal variation in the hippocampus. This study provides a detailed systematic analysis on spatial and temporal distribution of P2 in the mouse hippocampus. We found distinct spatial and temporal distribution patterns of the P2 receptors in different hippocampal layers. The temporal distribution of P2 receptors can be segregated into two large time domains, the early to mid-day and the mid to late night. This study provides an important basis for understanding dynamic P2 purinergic signaling in the hippocampal glia/neuronal network.
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Zera T, Moraes DJA, da Silva MP, Fisher JP, Paton JFR. The Logic of Carotid Body Connectivity to the Brain. Physiology (Bethesda) 2020; 34:264-282. [PMID: 31165684 DOI: 10.1152/physiol.00057.2018] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The carotid body has emerged as a therapeutic target for cardio-respiratory-metabolic diseases. With the expansive functions of the chemoreflex, we sought mechanisms to explain differential control of individual responses. We purport a remarkable correlation between phenotype of a chemosensory unit (glomus cell-sensory afferent) with a distinct component of the reflex response. This logic could permit differential modulation of distinct chemoreflex responses, a strategy ideal for therapeutic exploitation.
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Affiliation(s)
- Tymoteusz Zera
- Department of Experimental and Clinical Physiology, Laboratory of Centre for Preclinical Research, Medical University of Warsaw , Warsaw , Poland
| | - Davi J A Moraes
- Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo , São Paulo , Brazil
| | - Melina P da Silva
- Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo , São Paulo , Brazil
| | - James P Fisher
- Department of Physiology, Faculty of Medical & Health Sciences, University of Auckland , Auckland , New Zealand
| | - Julian F R Paton
- Department of Physiology, Faculty of Medical & Health Sciences, University of Auckland , Auckland , New Zealand
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Guan NN, Sharma N, Hallén-Grufman K, Jager EWH, Svennersten K. The role of ATP signalling in response to mechanical stimulation studied in T24 cells using new microphysiological tools. J Cell Mol Med 2018; 22:2319-2328. [PMID: 29392898 PMCID: PMC5867107 DOI: 10.1111/jcmm.13520] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 12/01/2017] [Indexed: 01/06/2023] Open
Abstract
The capacity to store urine and initiate voiding is a valued characteristic of the human urinary bladder. To maintain this feature, it is necessary that the bladder can sense when it is full and when it is time to void. The bladder has a specialized epithelium called urothelium that is believed to be important for its sensory function. It has been suggested that autocrine ATP signalling contributes to this sensory function of the urothelium. There is well‐established evidence that ATP is released via vesicular exocytosis as well as by pannexin hemichannels upon mechanical stimulation. However, there are still many details that need elucidation and therefore there is a need for the development of new tools to further explore this fascinating field. In this work, we use new microphysiological systems to study mechanostimulation at a cellular level: a mechanostimulation microchip and a silicone‐based cell stretcher. Using these tools, we show that ATP is released upon cell stretching and that extracellular ATP contributes to a major part of Ca2+ signalling induced by stretching in T24 cells. These results contribute to the increasing body of evidence for ATP signalling as an important component for the sensory function of urothelial cells. This encourages the development of drugs targeting P2 receptors to relieve suffering from overactive bladder disorder and incontinence.
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Affiliation(s)
- Na N Guan
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institutet, Stockholm, Sweden.,Department of Urology, Karolinska University Hospital, Stockholm, Sweden.,Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Nimish Sharma
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institutet, Stockholm, Sweden.,Department of Urology, Karolinska University Hospital, Stockholm, Sweden
| | - Katarina Hallén-Grufman
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institutet, Stockholm, Sweden.,Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Edwin W H Jager
- Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, Sweden
| | - Karl Svennersten
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institutet, Stockholm, Sweden.,Department of Urology, Karolinska University Hospital, Stockholm, Sweden
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Chen Y, Huang LYM. A simple and fast method to image calcium activity of neurons from intact dorsal root ganglia using fluorescent chemical Ca 2+ indicators. Mol Pain 2017; 13:1744806917748051. [PMID: 29212403 PMCID: PMC5731619 DOI: 10.1177/1744806917748051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Chemical calcium indicators have been commonly used to monitor calcium (Ca2+) activity in cell bodies, i.e., somata, of isolated dorsal root ganglion neurons. Recent studies have shown that dorsal root ganglion somata play an essential role in soma–glia interactions and actively participate in the transmission of nociceptive signals. It is therefore desirable to develop methods to study Ca2+ activity in neurons and glia in intact dorsal root ganglia. In our previous studies, we found that incubation of intact dorsal root ganglia with acetoxymethyl dye resulted in efficient Ca2+ dye loading into glial cells but limited dye loading into neurons. Here, we introduce a useful method to load Ca2+ dyes in intact dorsal root ganglion neurons through electroporation. We found that electroporation greatly facilitated loading of Fluo-4 acetoxymethyl, Oregon green bapta-1-488 acetoxymethyl, and Fluo-4 pentapotassium salt into dorsal root ganglion neurons. In contrast, electroporation did not further facilitate dye loading into glia. Using electroporation followed by incubation of acetoxymethyl form Ca2+ dye, we can load acetoxymethyl Ca2+ dye well in both neurons and glia. With this approach, we found that inflammation induced by complete Freund’s adjuvant significantly increased the incidence of neuron–glia interactions in dorsal root ganglia. We also confirmed the actions of capsaicin and morphine on Ca2+ responses in dorsal root ganglion neurons. Thus, by promoting the loading of Ca2+ dye in neurons and glia through electroporation and incubation, Ca2+ activities in neurons and neuron–glia interactions can be well studied in intact dorsal root ganglia.
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Affiliation(s)
- Yong Chen
- 1 Department of Neuroscience, Cell Biology and Anatomy, 12338 University of Texas Medical Branch, Galveston , TX, USA
| | - Li-Yen M Huang
- 1 Department of Neuroscience, Cell Biology and Anatomy, 12338 University of Texas Medical Branch, Galveston , TX, USA
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Yuryev M, Pellegrino C, Jokinen V, Andriichuk L, Khirug S, Khiroug L, Rivera C. In vivo Calcium Imaging of Evoked Calcium Waves in the Embryonic Cortex. Front Cell Neurosci 2016; 9:500. [PMID: 26778965 PMCID: PMC4701926 DOI: 10.3389/fncel.2015.00500] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/14/2015] [Indexed: 11/17/2022] Open
Abstract
The dynamics of intracellular calcium fluxes are instrumental in the proliferation, differentiation, and migration of neuronal cells. Knowledge thus far of the relationship between these calcium changes and physiological processes in the developing brain has derived principally from ex vivo and in vitro experiments. Here, we present a new method to image intracellular calcium flux in the cerebral cortex of live rodent embryos, whilst attached to the dam through the umbilical cord. Using this approach we demonstrate induction of calcium waves by laser stimulation. These waves are sensitive to ATP-receptor blockade and are significantly increased by pharmacological facilitation of intracellular-calcium release. This approach is the closest to physiological conditions yet achieved for imaging of calcium in the embryonic brain and as such opens new avenues for the study of prenatal brain development. Furthermore, the developed method could open the possibilities of preclinical translational studies in embryos particularly important for developmentally related diseases such as schizophrenia and autism.
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Affiliation(s)
- Mikhail Yuryev
- Neuroscience Center, University of Helsinki Helsinki, Finland
| | - Christophe Pellegrino
- INSERM U901, Institut de Neurobiologie de la Méditerranée (INMED), Parc Scientifique de LuminyMarseille, France; Aix-Marseille Université (AMU), UMR S901, Parc Scientifique de LuminyMarseille, France
| | - Ville Jokinen
- School of Chemical Technology, Aalto University Espoo, Finland
| | | | | | - Leonard Khiroug
- Neuroscience Center, University of Helsinki Helsinki, Finland
| | - Claudio Rivera
- Neuroscience Center, University of HelsinkiHelsinki, Finland; INSERM U901, Institut de Neurobiologie de la Méditerranée (INMED), Parc Scientifique de LuminyMarseille, France; Aix-Marseille Université (AMU), UMR S901, Parc Scientifique de LuminyMarseille, France
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Svennersten K, Hallén-Grufman K, de Verdier PJ, Wiklund NP, Poljakovic M. Localization of P2X receptor subtypes 2, 3 and 7 in human urinary bladder. BMC Urol 2015; 15:81. [PMID: 26253104 PMCID: PMC4529706 DOI: 10.1186/s12894-015-0075-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 07/28/2015] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Voiding dysfunctions are a common problem that has a severe negative impact on the quality of life. Today there is a need for new drug targets for these conditions. The role of ATP receptors in bladder physiology has been studied for some time, primarily in animal models. The aim of this work is to investigate the localization of the ATP receptors P2X2, P2X3 and P2X7 and their colocalization with vimentin and actin in the human urinary bladder. METHODS Immunohistochemical analysis was conducted on full-thickness bladder tissues from fundus and trigonum collected from 15 patients undergoing open radical cystectomy due to chronic cystitis, bladder cancer or locally advanced prostate cancer. Colocalization analyses were performed between the three different P2X subtypes and the structural proteins vimentin and actin. Specimens were examined using epifluorescence microscopy and correlation coefficients were calculated for each costaining as well as the mean distance from the laminin positive basal side of the urothelium to the vimentin positive cells located in the suburothelium. RESULTS P2X2 was expressed in vimentin positive cells located in the suburothelium. Less distinct labelling of P2X2 was also observed in actin positive smooth muscle cells and in the urothelium. P2X3 was expressed in vimentin positive cells surrounding the smooth muscle, and in vimentin positive cells located in the suburothelium. Weaker P2X3 labelling was seen in the urothelium. P2X7 was expressed in the smooth muscle cells and the urothelium. In the suburothelium, cells double positive for P2X2 and vimentin where located closer to the urothelium while cells double positive for P2X3 and vimentin where located further from the urothelium. CONCLUSION The results from this study demonstrate that there is a significant difference in the expression of the purinergic P2X2, P2X3 and P2X7 receptors in the different histological layers of the human urinary bladder.
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Affiliation(s)
- Karl Svennersten
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institutet, 171 76, Stockholm, Sweden.
- Department of Urology, Karolinska University Hospital, Stockholm, Sweden.
| | - Katarina Hallén-Grufman
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institutet, 171 76, Stockholm, Sweden.
- Department of Urology, Karolinska University Hospital, Stockholm, Sweden.
| | - Petra J de Verdier
- Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.
| | - N Peter Wiklund
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institutet, 171 76, Stockholm, Sweden.
- Department of Urology, Karolinska University Hospital, Stockholm, Sweden.
| | - Mirjana Poljakovic
- Department of Molecular Medicine and Surgery, Section of Urology, Karolinska Institutet, 171 76, Stockholm, Sweden.
- Department of Urology, Karolinska University Hospital, Stockholm, Sweden.
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Abstract
Most early studies of the role of nucleotides in development have evidenced their crucial importance as carriers of energy in all organisms. However, an increasing number of studies are now available to suggest that purines and pyrimidines, acting as extracellular ligands specifically on receptors of the plasma membrane, may play a pivotal role throughout pre- and postnatal development in a wide variety of organisms including amphibians, birds, and mammals. Purinergic receptor expression and functions have been studied in the development of many organs, including the autonomic nervous system (ANS). Nucleotide receptors can induce a multiplicity of cellular signalling pathways via crosstalk with bioactive molecules acting on growth factors and neurotransmitter receptors which are fundamental for the development of a mature and functional ANS. Purines and pyrimidines may influence all the stages of neuronal development, including neural cell proliferation, migration, differentiation and phenotype determination of differentiated cells. Indeed, the normal development of the ANS is disturbed by dysfunction of purinergic signalling in animal models. To establish the primitive and fundamental nature of purinergic neurotransmission in the ontogeny of the ANS, in this review the roles of purines and pyrimidines as signalling molecules during embryological and postnatal development are considered.
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Affiliation(s)
- Cristina Giaroni
- Department of Clinical and Experimental Medicine, University of Insubria, via H. Dunant 5, I-21100 Varese, Italy.
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Retamal MA, Reyes EP, Alcayaga J. Petrosal ganglion: a more complex role than originally imagined. Front Physiol 2014; 5:474. [PMID: 25538627 PMCID: PMC4255496 DOI: 10.3389/fphys.2014.00474] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 11/17/2014] [Indexed: 11/13/2022] Open
Abstract
The petrosal ganglion (PG) is a peripheral sensory ganglion, composed of pseudomonopolar sensory neurons that innervate the posterior third of the tongue and the carotid sinus and body. According to their electrical properties PG neurons can be ascribed to one of two categories: (i) neurons with action potentials presenting an inflection (hump) on its repolarizing phase and (ii) neurons with fast and brisk action potentials. Although there is some correlation between the electrophysiological properties and the sensory modality of the neurons in some species, no general pattern can be easily recognized. On the other hand, petrosal neurons projecting to the carotid body are activated by several transmitters, with acetylcholine and ATP being the most conspicuous in most species. Petrosal neurons are completely surrounded by a multi-cellular sheet of glial (satellite) cells that prevents the formation of chemical or electrical synapses between neurons. Thus, PG neurons are regarded as mere wires that communicate the periphery (i.e., carotid body) and the central nervous system. However, it has been shown that in other sensory ganglia satellite glial cells and their neighboring neurons can interact, partly by the release of chemical neuro-glio transmitters. This intercellular communication can potentially modulate the excitatory status of sensory neurons and thus the afferent discharge. In this mini review, we will briefly summarize the general properties of PG neurons and the current knowledge about the glial-neuron communication in sensory neurons and how this phenomenon could be important in the chemical sensory processing generated in the carotid body.
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Affiliation(s)
- Mauricio A Retamal
- Facultad de Medicina, Centro de Fisiología Celular e Integrativa, Clínica Alemana Universidad del Desarrollo Santiago, Chile
| | - Edison P Reyes
- Facultad de Medicina, Centro de Fisiología Celular e Integrativa, Clínica Alemana Universidad del Desarrollo Santiago, Chile ; Dirección de Investigación, Universidad Autónoma de Chile Temuco, Chile
| | - Julio Alcayaga
- Laboratorio de Fisiología Celular, Departamento de Biología, Facultad de Ciencias, Universidad de Chile Santiago, Chile
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Yao W, Yang H, Yin N, Ding G. Mast cell-nerve cell interaction at acupoint: modeling mechanotransduction pathway induced by acupuncture. Int J Biol Sci 2014; 10:511-9. [PMID: 24910530 PMCID: PMC4046878 DOI: 10.7150/ijbs.8631] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 03/27/2014] [Indexed: 01/28/2023] Open
Abstract
Mast cells are found abundant at sites of acupoints. Nerve cells share perivascular localization with mast cells. Acupuncture (mechanical stimuli) can activate mast cells to release adenosine triphosphate (ATP) which can activate nerve cells and modulates pain-processing pathways in response to acupuncture. In this paper, a mathematical model was constructed for describing intracellular Ca2+ signal and ATP release in a coupled mast cell and nerve cell system induced by mechanical stimuli. The results showed mechanical stimuli lead to a intracellular Ca2+ rise in the mast cell and ATP release, ATP diffuses in the extracellular space (ECS) and activates the nearby nerve cells, then induces electrical current in the nerve cell which spreads in the neural network. This study may facilitate our understanding of the mechanotransduction process induced by acupuncture and provide a methodology for quantitatively analyzing acupuncture treatment.
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Affiliation(s)
- Wei Yao
- Department of Mechanics and Engineering Science, Fudan University, 220 Handan Road, Shanghai, 200433, China
| | - Hongwei Yang
- Department of Mechanics and Engineering Science, Fudan University, 220 Handan Road, Shanghai, 200433, China
| | - Na Yin
- Department of Mechanics and Engineering Science, Fudan University, 220 Handan Road, Shanghai, 200433, China
| | - Guanghong Ding
- Department of Mechanics and Engineering Science, Fudan University, 220 Handan Road, Shanghai, 200433, China
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De Caro R, Macchi V, Sfriso MM, Porzionato A. Structural and neurochemical changes in the maturation of the carotid body. Respir Physiol Neurobiol 2013; 185:9-19. [DOI: 10.1016/j.resp.2012.06.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 05/16/2012] [Accepted: 06/08/2012] [Indexed: 02/07/2023]
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Carroll JL, Kim I. Carotid chemoreceptor "resetting" revisited. Respir Physiol Neurobiol 2012; 185:30-43. [PMID: 22982216 DOI: 10.1016/j.resp.2012.09.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 09/03/2012] [Accepted: 09/06/2012] [Indexed: 12/16/2022]
Abstract
Carotid body (CB) chemoreceptors transduce low arterial O(2) tension into increased action potential activity on the carotid sinus nerves, which contributes to resting ventilatory drive, increased ventilatory drive in response to hypoxia, arousal responses to hypoxia during sleep, upper airway muscle activity, blood pressure control and sympathetic tone. Their sensitivity to O(2) is low in the newborn and increases during the days or weeks after birth to reach adult levels. This postnatal functional maturation of the CB O(2) response has been termed "resetting" and it occurs in every mammalian species studied to date. The O(2) environment appears to play a key role; the fetus develops in a low O(2) environment throughout gestation and initiation of CB "resetting" after birth is modulated by the large increase in arterial oxygen tension occurring at birth. Although numerous studies have reported age-related changes in various components of the O(2) transduction cascade, how the O(2) environment shapes normal CB prenatal development and postnatal "resetting" remains unknown. Viewing CB "resetting" as environment-driven (developmental) phenotypic plasticity raises important mechanistic questions that have received little attention. This review examines what is known (and not known) about mechanisms of CB functional maturation, with a focus on the role of the O(2) environment.
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Affiliation(s)
- John L Carroll
- Division of Pediatric Pulmonary Medicine, Department of Pediatrics, University of Arkansas for Medical Sciences, Arkansas Children's Hospital, 1 Children's Way, Little Rock, AR 72202, United States.
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Bairam A, Niane LM, Joseph V. Role of ATP and adenosine on carotid body function during development. Respir Physiol Neurobiol 2012; 185:57-66. [PMID: 22721945 DOI: 10.1016/j.resp.2012.06.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Revised: 06/08/2012] [Accepted: 06/10/2012] [Indexed: 12/28/2022]
Abstract
The carotid body is the main peripheral oxygen sensor involved in cardio-respiratory control under both normoxic and hypoxic conditions. This review focuses on data from newborn animals related to the involvement of the purinergic system in carotid body function during development. We describe the potential effects mediated by ATP and adenosine receptors on ventilation, chemoreceptor activity and their influence on respiratory instability, such as apnea. The conclusions that appear from this review is that in newborn rats, activation of ATP receptors increases the carotid body function although with no age dependent manner, regulates breathing under normoxia, and enhances the initial increase in ventilation in response to hypoxia (likely reflecting carotid body responses). However, activation of adenosine receptors may play a role on carotid body function under chronic conditions, such as intermittent hypoxia or exposure to the adenosine receptor antagonist caffeine. Under the later conditions, an indirect effects involving the carotid body dopaminergic system are observed.
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Affiliation(s)
- Aida Bairam
- Centre de Recherche, D0-717, Hôpital Saint-François d'Assise, 10, rue de l'Espinay, Québec, Qc, Canada G1L 3L5.
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Niane LM, Joseph V, Bairam A. Systemic blockade of nicotinic and purinergic receptors inhibits ventilation and increases apnoea frequency in newborn rats. Exp Physiol 2012; 97:981-93. [DOI: 10.1113/expphysiol.2012.065011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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