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Braun J, Patel M, Kameneva T, Keatch C, Lambert G, Lambert E. Central stress pathways in the development of cardiovascular disease. Clin Auton Res 2024; 34:99-116. [PMID: 38104300 DOI: 10.1007/s10286-023-01008-x] [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: 08/30/2023] [Accepted: 12/02/2023] [Indexed: 12/19/2023]
Abstract
PURPOSE Mental stress is of essential consideration when assessing cardiovascular pathophysiology in all patient populations. Substantial evidence indicates associations among stress, cardiovascular disease and aberrant brain-body communication. However, our understanding of the flow of stress information in humans, is limited, despite the crucial insights this area may offer into future therapeutic targets for clinical intervention. METHODS Key terms including mental stress, cardiovascular disease and central control, were searched in PubMed, ScienceDirect and Scopus databases. Articles indicative of heart rate and blood pressure regulation, or central control of cardiovascular disease through direct neural innervation of the cardiac, splanchnic and vascular regions were included. Focus on human neuroimaging research and the flow of stress information is described, before brain-body connectivity, via pre-motor brainstem intermediates is discussed. Lastly, we review current understandings of pathophysiological stress and cardiovascular disease aetiology. RESULTS Structural and functional changes to corticolimbic circuitry encode stress information, integrated by the hypothalamus and amygdala. Pre-autonomic brain-body relays to brainstem and spinal cord nuclei establish dysautonomia and lead to alterations in baroreflex functioning, firing of the sympathetic fibres, cellular reuptake of norepinephrine and withdrawal of the parasympathetic reflex. The combined result is profoundly adrenergic and increases the likelihood of cardiac myopathy, arrhythmogenesis, coronary ischaemia, hypertension and the overall risk of future sudden stress-induced heart failure. CONCLUSIONS There is undeniable support that mental stress contributes to the development of cardiovascular disease. The emerging accumulation of large-scale multimodal neuroimaging data analytics to assess this relationship promises exciting novel therapeutic targets for future cardiovascular disease detection and prevention.
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Affiliation(s)
- Joe Braun
- School of Health Sciences, Swinburne University of Technology, PO Box 218, Hawthorn, Melbourne, VIC, 3122, Australia.
| | - Mariya Patel
- School of Health Sciences, Swinburne University of Technology, PO Box 218, Hawthorn, Melbourne, VIC, 3122, Australia
| | - Tatiana Kameneva
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Australia
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, Australia
- School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, Australia
| | - Charlotte Keatch
- School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, Australia
| | - Gavin Lambert
- School of Health Sciences, Swinburne University of Technology, PO Box 218, Hawthorn, Melbourne, VIC, 3122, Australia
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Australia
| | - Elisabeth Lambert
- School of Health Sciences, Swinburne University of Technology, PO Box 218, Hawthorn, Melbourne, VIC, 3122, Australia
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Australia
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2
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Krohn F, Novello M, van der Giessen RS, De Zeeuw CI, Pel JJM, Bosman LWJ. The integrated brain network that controls respiration. eLife 2023; 12:83654. [PMID: 36884287 PMCID: PMC9995121 DOI: 10.7554/elife.83654] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 01/29/2023] [Indexed: 03/09/2023] Open
Abstract
Respiration is a brain function on which our lives essentially depend. Control of respiration ensures that the frequency and depth of breathing adapt continuously to metabolic needs. In addition, the respiratory control network of the brain has to organize muscular synergies that integrate ventilation with posture and body movement. Finally, respiration is coupled to cardiovascular function and emotion. Here, we argue that the brain can handle this all by integrating a brainstem central pattern generator circuit in a larger network that also comprises the cerebellum. Although currently not generally recognized as a respiratory control center, the cerebellum is well known for its coordinating and modulating role in motor behavior, as well as for its role in the autonomic nervous system. In this review, we discuss the role of brain regions involved in the control of respiration, and their anatomical and functional interactions. We discuss how sensory feedback can result in adaptation of respiration, and how these mechanisms can be compromised by various neurological and psychological disorders. Finally, we demonstrate how the respiratory pattern generators are part of a larger and integrated network of respiratory brain regions.
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Affiliation(s)
- Friedrich Krohn
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands
| | - Manuele Novello
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands
| | | | - Chris I De Zeeuw
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands.,Netherlands Institute for Neuroscience, Royal Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Johan J M Pel
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands
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3
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Klemcke HG, Calderon ML, Ryan KL, Xiang L, Hinojosa-Laborde C. Effects of extremity trauma on physiological responses to hemorrhage in conscious rats. J Appl Physiol (1985) 2023; 134:203-215. [PMID: 36519571 PMCID: PMC9829477 DOI: 10.1152/japplphysiol.00191.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 12/09/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Although physiological responses to hemorrhage are well-studied, hemorrhage is often accompanied by trauma, and it remains unclear how injury affects these responses. This study examined effects of extremity trauma on cardiorespiratory responses and survival to moderate (37%; H-37) or severe (50%; H-50) hemorrhage in rats. Transmitter and carotid catheter implantation and extremity trauma (fibular fracture and muscle injury) were conducted 2 wk, 24 h, and 90 min, respectively, before conscious hemorrhage. Mean arterial pressure (MAP) and heart rate (HR; via telemetry), and respiration rate (RR), minute volume (MV), and tidal volume (TV; via plethysmography) were measured throughout the 25 min hemorrhage and remainder of the 4 h observation period. There were four groups: 1) H-37, no trauma (NT; n = 17); 2) H-37, extremity trauma (T, n = 18); 3) H-50, NT (n = 20); and 4) H-50, T (n = 20). For H-37, during and after hemorrhage, T increased HR (P ≤ 0.031) and MV (P ≤ 0.048) compared with NT rats. During H-50, T increased HR (0.041) and MV (P = 0.043). After hemorrhage, T increased MV (P = 0.008) but decreased HR (P = 0.007) and MAP (P = 0.039). All cardiorespiratory differences between T and NT groups were intermittent. Importantly, both survival time (159.8 ± 78.2 min vs. 211.9 ± 60.3 min; P = 0.022; mean ± SD) and percent survival (45% vs. 80%; P = 0.048) were less in T versus NT rats after H-50. Trauma interacts with physiological systems in a complex manner and no single cardiorespiratory measure was sufficiently altered to indicate that it alone could account for increased mortality after H-50.NEW & NOTEWORTHY In both civilian and military settings, severe hemorrhage rarely occurs in the absence of tissue trauma, yet many animal models for the study of hemorrhage do not include significant tissue trauma. This study using conscious unrestrained rats clearly demonstrates that extremity trauma worsens the probability of survival after a severe hemorrhage. Although no single cardiorespiratory factor accounted for the increased mortality, multiple modest time-related cardiorespiratory responses to the trauma were observed suggesting that their combined dysfunction may have contributed to the reduced survival.
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Affiliation(s)
- Harold G Klemcke
- US Army Institute of Surgical Research, Joint Base San Antonio-Fort Sam Houston, San Antonio, Texas
| | - Mariam L Calderon
- US Army Institute of Surgical Research, Joint Base San Antonio-Fort Sam Houston, San Antonio, Texas
| | - Kathy L Ryan
- US Army Institute of Surgical Research, Joint Base San Antonio-Fort Sam Houston, San Antonio, Texas
| | - Lusha Xiang
- US Army Institute of Surgical Research, Joint Base San Antonio-Fort Sam Houston, San Antonio, Texas
| | - Carmen Hinojosa-Laborde
- US Army Institute of Surgical Research, Joint Base San Antonio-Fort Sam Houston, San Antonio, Texas
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4
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Lynch E, Dempsey B, Saleeba C, Monteiro E, Turner A, Burke PGR, Allen AM, Dampney RAL, Hildreth CM, Cornish JL, Goodchild AK, McMullan S. Descending pathways from the superior colliculus mediating autonomic and respiratory effects associated with orienting behaviour. J Physiol 2022; 600:5311-5332. [PMID: 36271640 PMCID: PMC10107157 DOI: 10.1113/jp283789] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 10/14/2022] [Indexed: 01/05/2023] Open
Abstract
The ability to discriminate competing external stimuli and initiate contextually appropriate behaviours is a key brain function. Neurons in the deep superior colliculus (dSC) integrate multisensory inputs and activate descending projections to premotor pathways responsible for orienting, attention and defence, behaviours which involve adjustments to respiratory and cardiovascular parameters. However, the neural pathways that subserve the physiological components of orienting are poorly understood. We report that orienting responses to optogenetic dSC stimulation are accompanied by short-latency autonomic, respiratory and electroencephalographic effects in awake rats, closely mimicking those evoked by naturalistic alerting stimuli. Physiological responses were not accompanied by detectable aversion or fear, and persisted under urethane anaesthesia, indicating independence from emotional stress. Anterograde and trans-synaptic viral tracing identified a monosynaptic pathway that links the dSC to spinally projecting neurons in the medullary gigantocellular reticular nucleus (GiA), a key hub for the coordination of orienting and locomotor behaviours. In urethane-anaesthetized animals, sympathoexcitatory and cardiovascular, but not respiratory, responses to dSC stimulation were replicated by optogenetic stimulation of the dSC-GiA terminals, suggesting a likely role for this pathway in mediating the autonomic components of dSC-mediated responses. Similarly, extracellular recordings from putative GiA sympathetic premotor neurons confirmed short-latency excitatory inputs from the dSC. This pathway represents a likely substrate for autonomic components of orienting responses that are mediated by dSC neurons and suggests a mechanism through which physiological and motor components of orienting behaviours may be integrated without the involvement of higher centres that mediate affective components of defensive responses. KEY POINTS: Neurons in the deep superior colliculus (dSC) integrate multimodal sensory signals to elicit context-dependent innate behaviours that are accompanied by stereotypical cardiovascular and respiratory activities. The pathways responsible for mediating the physiological components of colliculus-mediated orienting behaviours are unknown. We show that optogenetic dSC stimulation evokes transient orienting, respiratory and autonomic effects in awake rats which persist under urethane anaesthesia. Anterograde tracing from the dSC identified projections to spinally projecting neurons in the medullary gigantocellular reticular nucleus (GiA). Stimulation of this pathway recapitulated autonomic effects evoked by stimulation of dSC neurons. Electrophysiological recordings from putative GiA sympathetic premotor neurons confirmed short latency excitatory input from dSC neurons. This disynaptic dSC-GiA-spinal sympathoexcitatory pathway may underlie autonomic adjustments to salient environmental cues independent of input from higher centres.
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Affiliation(s)
- Erin Lynch
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Bowen Dempsey
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Christine Saleeba
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Eloise Monteiro
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Anita Turner
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Peter G R Burke
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Andrew M Allen
- Department of Physiology, University of Melbourne, Victoria, Australia
| | - Roger A L Dampney
- School of Medical Sciences (Physiology), University of Sydney, Sydney, New South Wales, Australia
| | - Cara M Hildreth
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Jennifer L Cornish
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Ann K Goodchild
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Simon McMullan
- Macquarie Medical School, Faculty of Medicine, Health & Human Sciences, Macquarie University, Sydney, New South Wales, Australia
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5
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Schottelkotte KM, Crone SA. Forebrain control of breathing: Anatomy and potential functions. Front Neurol 2022; 13:1041887. [PMID: 36388186 PMCID: PMC9663927 DOI: 10.3389/fneur.2022.1041887] [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: 09/11/2022] [Accepted: 10/11/2022] [Indexed: 01/25/2023] Open
Abstract
The forebrain plays important roles in many critical functions, including the control of breathing. We propose that the forebrain is important for ensuring that breathing matches current and anticipated behavioral, emotional, and physiological needs. This review will summarize anatomical and functional evidence implicating forebrain regions in the control of breathing. These regions include the cerebral cortex, extended amygdala, hippocampus, hypothalamus, and thalamus. We will also point out areas where additional research is needed to better understand the specific roles of forebrain regions in the control of breathing.
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Affiliation(s)
- Karl M. Schottelkotte
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Steven A. Crone
- Division of Pediatric Neurosurgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States,Department of Neurosurgery, University of Cincinnati College of Medicine, Cincinnati, OH, United States,*Correspondence: Steven A. Crone
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6
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Ujita A, Seekford Z, Kott M, Goncherenko G, Dias NW, Feuerbacher E, Bergamasco L, Jacobs L, Eversole DE, Negrão JA, Mercadante VRG. Habituation Protocols Improve Behavioral and Physiological Responses of Beef Cattle Exposed to Students in an Animal Handling Class. Animals (Basel) 2021; 11:ani11082159. [PMID: 34438617 PMCID: PMC8388410 DOI: 10.3390/ani11082159] [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: 05/30/2021] [Revised: 07/02/2021] [Accepted: 07/12/2021] [Indexed: 11/17/2022] Open
Abstract
Simple Summary Students in agricultural programs have the opportunity to interact with animals during different teaching activities. However, students’ interactions with livestock may be distressing to the animals and can affect the students’ and animals’ safety. We investigate whether two human-animal habituation strategies, one with positive tactile stimulation and one without, would improve behavioral and physiological responses of beef heifers during a livestock handling class. Overall, heifers that received a habituation treatment had more positive behavior responses, and decreased physiological stress responses in comparison to heifers that were not exposed to habituation. Furthermore, the heifers exposed to the habituation with a positive tactile stimulation had the greatest improvements in behavior in comparison to control and non-stimulated heifers, exhibiting more positive behaviors when interacting with humans. Strategies to habituate cattle to human interaction with positive stimulation aligned with training humans that handle and interact with cattle on best practices and cattle behavior can improve behavior, reduce stress-related physiological responses and enhance safety for both humans and animals. Abstract Our objective was to determine the impact of different habituation protocols on beef cattle behavior, physiology, and temperament in response to human handling. Beef heifers were exposed to three habituation strategies: (1) tactile stimulation (brushing) in the working chute for seven consecutive days (STI; n = 18); (2) passage through the working chute for seven consecutive days (CHU; n = 19) and; (3) no habituation (CON; n = 19). Individual heifer respiratory rate (RR; n/min), internal vaginal temperature (VAGT; °C), and blood cortisol were measured. Further, behavior parameters were observed to generate a behavior score, and heifer interaction with students and their behavioral responses were recorded. Habituation with STI and CHU resulted in improved numerical behavioral scores compared to CON, and greater (p ≤ 0.05) handling latencies. Vaginal temperature was decreased in STI compared to CHU and CONT (p ≤ 0.05). Cortisol concentration did not differ among treatments, but decreased (p ≤ 0.05) from the start of the experiment to 14 days after treatment initiation. Both habituation protocols showed benefits, but heifers that received the positive tactile stimulation in the chute had the greatest behavior improvements. Furthermore, these heifers responded more calmly during student-animal interactions in class, which is beneficial for the students’ and animals’ safety.
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Affiliation(s)
- Aska Ujita
- Basic Science Department, Faculty of Animal Science and Food Engineering, University of São Paulo, Pirassununga, SP 13635-900, Brazil; (A.U.); (J.A.N.)
| | - Zachary Seekford
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA; (Z.S.); (M.K.); (N.W.D.); (E.F.); (L.B.); (L.J.); (D.E.E.)
| | - Michelle Kott
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA; (Z.S.); (M.K.); (N.W.D.); (E.F.); (L.B.); (L.J.); (D.E.E.)
| | - Guillermo Goncherenko
- Polo Agroflorestal CENUR-Noroeste, Faculdad de Veterinaria, Universidad de la Republica, Melo, CL 91500, Uruguay;
| | - Nicholas W. Dias
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA; (Z.S.); (M.K.); (N.W.D.); (E.F.); (L.B.); (L.J.); (D.E.E.)
| | - Erica Feuerbacher
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA; (Z.S.); (M.K.); (N.W.D.); (E.F.); (L.B.); (L.J.); (D.E.E.)
| | - Luciana Bergamasco
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA; (Z.S.); (M.K.); (N.W.D.); (E.F.); (L.B.); (L.J.); (D.E.E.)
| | - Leonie Jacobs
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA; (Z.S.); (M.K.); (N.W.D.); (E.F.); (L.B.); (L.J.); (D.E.E.)
| | - Dan E. Eversole
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA; (Z.S.); (M.K.); (N.W.D.); (E.F.); (L.B.); (L.J.); (D.E.E.)
| | - João A. Negrão
- Basic Science Department, Faculty of Animal Science and Food Engineering, University of São Paulo, Pirassununga, SP 13635-900, Brazil; (A.U.); (J.A.N.)
| | - Vitor R. G. Mercadante
- Department of Animal and Poultry Sciences, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA 24060, USA; (Z.S.); (M.K.); (N.W.D.); (E.F.); (L.B.); (L.J.); (D.E.E.)
- Department of Large Animal Clinical Sciences, VA-MD College of Veterinary Medicine, Virginia Tech. Blacksburg, VA 24060, USA
- Correspondence:
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Mendonça MM, Costa AN, Moraes GCA, Martins GM, Almeida AF, Rincon GCN, Siqueira JPR, Padilha DM, Moya MI, Ferreira-Neto ML, Gomes RM, Pedrino GR, Fontes MAP, Colombari E, Crestani CC, Fajemiroye JO, Xavier CH. Centrally acting antihypertensives change the psychogenic cardiovascular reactivity. Fundam Clin Pharmacol 2021; 35:892-905. [PMID: 33465820 DOI: 10.1111/fcp.12648] [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: 11/03/2020] [Revised: 12/21/2020] [Accepted: 01/15/2021] [Indexed: 11/27/2022]
Abstract
Clonidine (CL) and Rilmenidine (RI) are among the most frequently prescribed centrally acting antihypertensives. Here, we compared CL and RI effects on psychogenic cardiovascular reactivity to sonant, luminous, motosensory, and vibrotactile stimuli during neurogenic hypertension. The femoral artery and vein of Wistar (WT - normotensive) and spontaneously hypertensive rats (SHR) were catheterized before (24 h interval) i.p. injection of vehicle (NaCl 0.9%, control - CT group), CL (10 µg/kg), or RI (10 µg/kg) and acute exposure to luminous (5000 lm), sonant (75 dB sudden tap), motor (180° cage twist), and air-jet (10 L/min - restraint and vibrotactile). Findings showed that: (i) CL or RI reduced the arterial pressure of SHR, without affecting basal heart rate in WT and SHR; (ii) different stimuli evoked pressor and tachycardic responses; (iii) CL and RI reduced pressor response to sound; (iv) CL or RI reduced pressor responses to luminous stimulus without a change in peak tachycardia in SHR; (v) cage twist increased blood pressure in SHR, which was attenuated by CL or RI; (vi) air-jet increased pressure and heart rate; (vii) CL or RI attenuated the pressor responses to air-jet in SHR while RI reduced the chronotropic reactivity in both strains. Altogether, both antihypertensives relieved the psychogenic cardiovascular responses to different stimuli. The RI elicited higher cardioprotective effects through a reduction in air-jet-induced tachycardia.
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Affiliation(s)
- Michelle M Mendonça
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil
| | - Amanda N Costa
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil
| | - Gean C A Moraes
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil
| | - Gustavo M Martins
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil.,School of Medicine, Federal University of Goias, Goiania, Brazil
| | - Aline F Almeida
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil.,School of Medicine, Federal University of Goias, Goiania, Brazil
| | - Gabriel C N Rincon
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil.,School of Medicine, Federal University of Goias, Goiania, Brazil
| | - João P R Siqueira
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil.,School of Medicine, Federal University of Goias, Goiania, Brazil
| | - Daniella M Padilha
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil.,School of Medicine, Federal University of Goias, Goiania, Brazil
| | - Marcela I Moya
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil.,School of Medicine, Federal University of Goias, Goiania, Brazil
| | | | - Rodrigo Mello Gomes
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil
| | | | | | - Eduardo Colombari
- School of Dentistry, São Paulo State University (UNESP), Araraquara, Brazil
| | - Carlos C Crestani
- School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, Brazil
| | - James O Fajemiroye
- Institute of Biological Sciences, Federal University of Goias, Goiania, Brazil
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8
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Moreira TS, Sobrinho CR, Falquetto B, Oliveira LM, Lima JD, Mulkey DK, Takakura AC. The retrotrapezoid nucleus and the neuromodulation of breathing. J Neurophysiol 2020; 125:699-719. [PMID: 33427575 DOI: 10.1152/jn.00497.2020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Breathing is regulated by a host of arousal and sleep-wake state-dependent neuromodulators to maintain respiratory homeostasis. Modulators such as acetylcholine, norepinephrine, histamine, serotonin (5-HT), adenosine triphosphate (ATP), substance P, somatostatin, bombesin, orexin, and leptin can serve complementary or off-setting functions depending on the target cell type and signaling mechanisms engaged. Abnormalities in any of these modulatory mechanisms can destabilize breathing, suggesting that modulatory mechanisms are not overly redundant but rather work in concert to maintain stable respiratory output. The present review focuses on the modulation of a specific cluster of neurons located in the ventral medullary surface, named retrotrapezoid nucleus, that are activated by changes in tissue CO2/H+ and regulate several aspects of breathing, including inspiration and active expiration.
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Affiliation(s)
- Thiago S Moreira
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo (USP), São Paulo, Brazil
| | - Cleyton R Sobrinho
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo (USP), São Paulo, Brazil
| | - Barbara Falquetto
- Department of Pharmacology, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo (USP), São Paulo, Brazil
| | - Luiz M Oliveira
- Department of Pharmacology, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo (USP), São Paulo, Brazil
| | - Janayna D Lima
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo (USP), São Paulo, Brazil
| | - Daniel K Mulkey
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut
| | - Ana C Takakura
- Department of Pharmacology, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo (USP), São Paulo, Brazil
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9
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Poole EI, McGavin JJ, Cochkanoff NL, Crosby KM. Stereotaxic surgery for implantation of guide cannulas for microinjection into the dorsomedial hypothalamus in young rats. MethodsX 2019; 6:1652-1659. [PMID: 31372353 PMCID: PMC6660514 DOI: 10.1016/j.mex.2019.07.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 07/03/2019] [Indexed: 11/30/2022] Open
Abstract
Stereotaxic surgery to implant guide cannulas into the rodent brain is a frequently used technique to deliver drugs to targeted brain regions in awake, freely moving animals. There are limited reports, however, of central injections in young animals, and no information on cannula implantation for drug administration into the dorsomedial hypothalamus (DMH) in young rats. Our protocol describes a simple and successful method for implanting guide cannulas in the brains of young, male Sprague-Dawley rats and outlines newly developed stereotaxic coordinates to accurately target the dorsomedial hypothalamus. Stereotaxic surgical procedure for guide cannula implantation in the DMH in young rats. Development of stereotaxic coordinates of the DMH in young rats. Microinjection of drugs into the young rat brain.
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Affiliation(s)
- Emily I Poole
- Biology Department, Mount Allison University, 63B York Street, Sackville, New Brunswick, E4L 1G7, Canada
| | - Jacob J McGavin
- Biology Department, Mount Allison University, 63B York Street, Sackville, New Brunswick, E4L 1G7, Canada
| | - Nicholas L Cochkanoff
- Biology Department, Mount Allison University, 63B York Street, Sackville, New Brunswick, E4L 1G7, Canada
| | - Karen M Crosby
- Biology Department, Mount Allison University, 63B York Street, Sackville, New Brunswick, E4L 1G7, Canada
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10
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Fukushi I, Yokota S, Okada Y. The role of the hypothalamus in modulation of respiration. Respir Physiol Neurobiol 2018; 265:172-179. [PMID: 30009993 DOI: 10.1016/j.resp.2018.07.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 06/17/2018] [Accepted: 07/10/2018] [Indexed: 01/18/2023]
Abstract
The hypothalamus is a higher center of the autonomic nervous system and maintains essential body homeostasis including respiration. The paraventricular nucleus, perifornical area, dorsomedial hypothalamus, and lateral and posterior hypothalamus are the primary nuclei of the hypothalamus critically involved in respiratory control. These hypothalamic nuclei are interconnected with respiratory nuclei located in the midbrain, pons, medulla and spinal cord. We provide an extensive review of the role of the above hypothalamic nuclei in the maintenance of basal ventilation, and modulation of respiration in hypoxic and hypercapnic conditions, during dynamic exercise, in awake and sleep states, and under stress. Dysfunction of the hypothalamus causes abnormal breathing and hypoventilation. However, the cellular and molecular mechanisms how the hypothalamus integrates and modulates autonomic and respiratory functions remain to be elucidated.
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Affiliation(s)
- Isato Fukushi
- Clinical Research Center, Murayama Medical Center, 2-37-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan.
| | - Shigefumi Yokota
- Department of Anatomy and Neuroscience, Shimane University School of Medicine, 89-1 Enya-cho, Izumo 693-8501, Japan
| | - Yasumasa Okada
- Clinical Research Center, Murayama Medical Center, 2-37-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan
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11
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Martin-Fardon R, Cauvi G, Kerr TM, Weiss F. Differential role of hypothalamic orexin/hypocretin neurons in reward seeking motivated by cocaine versus palatable food. Addict Biol 2018; 23:6-15. [PMID: 27558790 DOI: 10.1111/adb.12441] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 07/28/2016] [Indexed: 01/31/2023]
Abstract
Hypothalamic orexin/hypocretin (Orx/Hcrt) neurons are thought to mediate both food-reinforced behaviors and behavior motivated by drugs of abuse. However, the relative role of the Orx/Hcrt system in behavior motivated by food versus drugs of abuse remains unclear. This investigation addressed this question by contrasting hypothalamic Orx/Hcrt neuronal activation associated with reinstatement of reward seeking induced by stimuli conditioned to cocaine (COC) versus highly palatable food reward, sweetened condensed milk (SCM). Orx/Hcrt neuronal activation in the lateral hypothalamus, dorsomedial hypothalamus and perifornical area, determined by dual c-fos/orx immunocytochemistry, was quantified in rat brains, following reinstatement of reward seeking induced by a discriminative stimulus (S+ ) conditioned to COC or SCM. The COC S+ and SCM S+ initially produced the same magnitude of reward seeking. However, over four subsequent tests, behavior induced by the SCM S+ decreased to extinction levels, whereas reinstatement induced by the COC S+ perseverated at undiminished levels. Following both the first and fourth tests, the percentage of Orx/Hcrt cells expressing Fos was significantly increased in all hypothalamic subregions in rats tested with the COC S+ but not rats tested with the SCM S+ . These findings point toward a role for the Orx/Hcrt system in perseverating, compulsive-like COC seeking but not behavior motivated by palatable food. Moreover, analysis of the Orx/Hcrt recruitment patterns suggests that failure of Orx/Hcrt neurons in the lateral hypothalamus to respond to inhibitory inputs from Orx/Hcrt neurons in the dorsomedial hypothalamus/perifornical area may contribute to the perseverating nature of COC seeking.
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Affiliation(s)
- Rémi Martin-Fardon
- Molecular and Cellular Neuroscience Department; The Scripps Research Institute; La Jolla CA USA
| | - Gabrielle Cauvi
- Molecular and Cellular Neuroscience Department; The Scripps Research Institute; La Jolla CA USA
| | - Tony M. Kerr
- Molecular and Cellular Neuroscience Department; The Scripps Research Institute; La Jolla CA USA
| | - Friedbert Weiss
- Molecular and Cellular Neuroscience Department; The Scripps Research Institute; La Jolla CA USA
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12
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A hypothalamo-midbrain-medullary pathway involved in the inhibition of the respiratory chemoreflex response induced by potassium cyanide in rodents. Neuropharmacology 2017; 128:152-167. [PMID: 28987939 DOI: 10.1016/j.neuropharm.2017.09.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/07/2017] [Accepted: 09/26/2017] [Indexed: 01/05/2023]
Abstract
Recent studies have demonstrated that a mild stimulation of the dorsomedian nucleus of the hypothalamus (DMH), a defense area, induces the inhibition of the carotid chemoreflex tachypnea. DMH activation reduces the cardiac chemoreflex response via the dorsolateral part of the periaqueductal grey matter (dlPAG) and serotonin receptors (5-HT3 subtype) in the nucleus tractus solitarius (NTS). The objectives of this study were to assess whether dlPAG and subsequent NTS 5-HT3 receptors are involved in chemoreflex tachypnea inhibition during mild activation of the DMH. For this purpose, peripheral chemoreflex was activated with potassium cyanide (KCN, 40 μg/rat, i.v.) during electrical and chemical minimal supra-threshold (mild) stimulation of the dlPAG or DMH. In both situations, changes in respiratory frequency (RF) following KCN administration were reduced. Moreover, pharmacological blockade of the dlPAG prevented DMH-induced KCN tachypnea inhibition. Activation of NTS 5-HT3 receptors also reduced chemoreflex tachypnea in a dose-dependent manner. In addition, blockade of NTS 5-HT3 receptors with granisetron (2.5 but not 1.25 mM), or the use of mice lacking the 5-HT3a receptor (5-HT3a KO), prevented dlPAG-induced KCN reductions in RF. A respiratory hypothalamo-midbrain-medullary pathway (HMM) therefore plays a crucial role in the inhibition of the hyperventilatory response to carotid chemoreflex.
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13
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Dampney RAL. Central neural control of the cardiovascular system: current perspectives. ADVANCES IN PHYSIOLOGY EDUCATION 2016; 40:283-296. [PMID: 27445275 DOI: 10.1152/advan.00027.2016] [Citation(s) in RCA: 147] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 05/23/2016] [Indexed: 06/06/2023]
Abstract
This brief review, which is based on a lecture presented at the American Physiological Society Teaching Refresher Course on the Brain and Systems Control as part of the Experimental Biology meeting in 2015, aims to summarize current concepts of the principal mechanisms in the brain that regulate the autonomic outflow to the cardiovascular system. Such cardiovascular regulatory mechanisms do not operate in isolation but are closely coordinated with respiratory and other regulatory mechanisms to maintain homeostasis. The brain regulates the cardiovascular system by two general means: 1) feedforward regulation, often referred to as "central command," and 2) feedback or reflex regulation. In most situations (e.g., during exercise, defensive behavior, sleep, etc.), both of these general mechanisms contribute to overall cardiovascular homeostasis. The review first describes the mechanisms and central circuitry subserving the baroreceptor, chemoreceptor, and other reflexes that work together to regulate an appropriate level of blood pressure and blood oxygenation and then considers the brain mechanisms that defend the body against more complex environmental challenges, using dehydration and cold and heat stress as examples. The last section of the review considers the central mechanisms regulating cardiovascular function associated with different behaviors, with a specific focus on defensive behavior and exercise.
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Affiliation(s)
- Roger A L Dampney
- School of Medical Sciences (Physiology) and Bosch Institute, The University of Sydney, Sydney, New South Wales, Australia
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Brouillard C, Carrive P, Camus F, Bénoliel JJ, Similowski T, Sévoz-Couche C. Long-lasting bradypnea induced by repeated social defeat. Am J Physiol Regul Integr Comp Physiol 2016; 311:R352-64. [DOI: 10.1152/ajpregu.00021.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 05/18/2016] [Indexed: 12/17/2022]
Abstract
Repeated social defeat in the rat induces long-lasting cardiovascular changes associated with anxiety. In this study, we investigated the effects of repeated social defeat on breathing. Respiratory rate was extracted from the respiratory sinus arrhythmia (RSA) peak frequency of the ECG in rats subjected to social defeat for 4 consecutive days. Respiratory rate was recorded under anesthesia 6 days (D+10) or 26 days (D+30) after social defeat. At D+10, defeated (D) rats spent less time in the open arms of the elevated plus maze test, had heavier adrenal glands, and displayed bradypnea, unlike nondefeated animals. At D+30, all signs of anxiety had disappeared. However, one-half of the rats still displayed bradypnea (DL rats, for low respiratory rate indicated by a lower RSA frequency), whereas those with higher respiratory rate (DH rats) had recovered. Acute blockade of the dorsomedial hypothalamus (DMH) or nucleus tractus solitarii (NTS) 5-HT3 receptors reversed bradypnea in all D rats at D+10 and in DL rats at D+30. Respiratory rate was also recorded in conscious animals implanted with radiotelemetric ECG probes. DH rats recovered between D+10 and D+18, whereas DL rats remained bradypneic until D+30. In conclusion, social stress induces sustained chronic bradypnea mediated by DMH neurons and NTS 5-HT3 receptors. These changes are associated with an anxiety-like state that persists until D+10, followed by recovery. However, bradypnea may persist in one-half of the population up until D+30, despite apparent recovery of the anxiety-like state.
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Affiliation(s)
- Charly Brouillard
- Centre de Recherche de l'Institut du Cerveau et de la Moelle Epinière, Institut National de la Santé et de la Recherche Médicale, UMR-S 975, Centre National de la Recherche Scientifique, UMR 7225, Faculté de Médecine University Pierre and Marie Curie, Site Pitié-Salpêtrière, Paris, France
- Sorbonne Universités, University Pierre and Marie Curie University Paris 06, Institut National de la Santé et de la Recherche Médicale, UMRS1158, Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France
| | - Pascal Carrive
- Blood Pressure, Brain and Behavior Laboratory, School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Françoise Camus
- Centre de Recherche de l'Institut du Cerveau et de la Moelle Epinière, Institut National de la Santé et de la Recherche Médicale, UMR-S 975, Centre National de la Recherche Scientifique, UMR 7225, Faculté de Médecine University Pierre and Marie Curie, Site Pitié-Salpêtrière, Paris, France
| | - Jean-Jacques Bénoliel
- Centre de Recherche de l'Institut du Cerveau et de la Moelle Epinière, Institut National de la Santé et de la Recherche Médicale, UMR-S 975, Centre National de la Recherche Scientifique, UMR 7225, Faculté de Médecine University Pierre and Marie Curie, Site Pitié-Salpêtrière, Paris, France
| | - Thomas Similowski
- Sorbonne Universités, University Pierre and Marie Curie University Paris 06, Institut National de la Santé et de la Recherche Médicale, UMRS1158, Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France
- Assistance Publique-Hôpitaux de Paris, Groupe Hospitalier Pitié-Salpêtrière, Charles Foix, Service de Pneumologie et Réanimation Médicale, Paris, France; and
| | - Caroline Sévoz-Couche
- Centre de Recherche de l'Institut du Cerveau et de la Moelle Epinière, Institut National de la Santé et de la Recherche Médicale, UMR-S 975, Centre National de la Recherche Scientifique, UMR 7225, Faculté de Médecine University Pierre and Marie Curie, Site Pitié-Salpêtrière, Paris, France
- Sorbonne Universités, University Pierre and Marie Curie University Paris 06, Institut National de la Santé et de la Recherche Médicale, UMRS1158, Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France
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15
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Müller-Ribeiro FC, Goodchild AK, McMullan S, Fontes MA, Dampney RA. Coordinated autonomic and respiratory responses evoked by alerting stimuli: Role of the midbrain colliculi. Respir Physiol Neurobiol 2016; 226:87-93. [DOI: 10.1016/j.resp.2015.10.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 10/21/2015] [Accepted: 10/23/2015] [Indexed: 10/22/2022]
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16
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Zafar T, Brouillard C, Sévoz-Couche C. Respiratory chemoreflex response inhibition by dorsomedian hypothalamic nucleus activation in rats. Respir Physiol Neurobiol 2015; 247:188-191. [PMID: 26590324 DOI: 10.1016/j.resp.2015.11.001] [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: 08/24/2015] [Revised: 10/26/2015] [Accepted: 11/02/2015] [Indexed: 10/22/2022]
Abstract
Recent observations from our group seem to indicate that repeated stress-evoked dorsomedian hypothalamic nucleus (DMH) activation in rats can lead to persistent bradypnea. One possibility was that respiratory responses to peripheral chemoreceptor activation were reduced by DMH stimulation. In the present study, we therefore investigated the effect of minimal supra-threshold DMH stimulation on respiratory carotid chemoreflex responses. For this purpose, the chemoreflex was activated by potassium cyanide (KCN, 40μg/rat, i.v.) during electrical and chemical stimulation of the DMH. In both situations, changes in breathing frequency but not tidal volume responses to KCN administration were reduced. These findings suggest that low DMH neurotransmission negatively affects respiratory chemoreflex responses and may be involved in stress-induced bradypnea.
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Affiliation(s)
- Tabinda Zafar
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMR_S 1158, Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France; APHP, Groupe Hospitalier Pitié-Salpêtrière, Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3J), 75013 Paris, France
| | - Charly Brouillard
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMR_S 1158, Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France; APHP, Groupe Hospitalier Pitié-Salpêtrière, Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3J), 75013 Paris, France
| | - Caroline Sévoz-Couche
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMR_S 1158, Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France; APHP, Groupe Hospitalier Pitié-Salpêtrière, Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3J), 75013 Paris, France.
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17
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Dampney RAL. Central mechanisms regulating coordinated cardiovascular and respiratory function during stress and arousal. Am J Physiol Regul Integr Comp Physiol 2015; 309:R429-43. [DOI: 10.1152/ajpregu.00051.2015] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 05/28/2015] [Indexed: 02/07/2023]
Abstract
Actual or potentially threatening stimuli in the external environment (i.e., psychological stressors) trigger highly coordinated defensive behavioral responses that are accompanied by appropriate autonomic and respiratory changes. As discussed in this review, several brain regions and pathways have major roles in subserving the cardiovascular and respiratory responses to threatening stimuli, which may vary from relatively mild acute arousing stimuli to more prolonged life-threatening stimuli. One key region is the dorsomedial hypothalamus, which receives inputs from the cortex, amygdala, and other forebrain regions and which is critical for generating autonomic, respiratory, and neuroendocrine responses to psychological stressors. Recent studies suggest that the dorsomedial hypothalamus also receives an input from the dorsolateral column in the midbrain periaqueductal gray, which is another key region involved in the integration of stress-evoked cardiorespiratory responses. In addition, it has recently been shown that neurons in the midbrain colliculi can generate highly synchronized autonomic, respiratory, and somatomotor responses to visual, auditory, and somatosensory inputs. These collicular neurons may be part of a subcortical defense system that also includes the basal ganglia and which is well adapted to responding to threats that require an immediate stereotyped response that does not involve the cortex. The basal ganglia/colliculi system is phylogenetically ancient. In contrast, the defense system that includes the dorsomedial hypothalamus and cortex evolved at a later time, and appears to be better adapted to generating appropriate responses to more sustained threatening stimuli that involve cognitive appraisal.
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Affiliation(s)
- Roger A. L. Dampney
- School of Medical Sciences (Physiology) and Bosch Institute, University of Sydney, New South Wales, Australia
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18
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Zhang J, Luo H, Pace E, Li L, Liu B. Psychophysical and neural correlates of noised-induced tinnitus in animals: Intra- and inter-auditory and non-auditory brain structure studies. Hear Res 2015; 334:7-19. [PMID: 26299842 DOI: 10.1016/j.heares.2015.08.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 08/04/2015] [Accepted: 08/17/2015] [Indexed: 12/19/2022]
Abstract
Tinnitus, a ringing in the ear or head without an external sound source, is a prevalent health problem. It is often associated with a number of limbic-associated disorders such as anxiety, sleep disturbance, and emotional distress. Thus, to investigate tinnitus, it is important to consider both auditory and non-auditory brain structures. This paper summarizes the psychophysical, immunocytochemical and electrophysiological evidence found in rats or hamsters with behavioral evidence of tinnitus. Behaviorally, we tested for tinnitus using a conditioned suppression/avoidance paradigm, gap detection acoustic reflex behavioral paradigm, and our newly developed conditioned licking suppression paradigm. Our new tinnitus behavioral paradigm requires relatively short baseline training, examines frequency specification of tinnitus perception, and achieves sensitive tinnitus testing at an individual level. To test for tinnitus-related anxiety and cognitive impairment, we used the elevated plus maze and Morris water maze. Our results showed that not all animals with tinnitus demonstrate anxiety and cognitive impairment. Immunocytochemically, we found that animals with tinnitus manifested increased Fos-like immunoreactivity (FLI) in both auditory and non-auditory structures. The manner in which FLI appeared suggests that lower brainstem structures may be involved in acute tinnitus whereas the midbrain and cortex are involved in more chronic tinnitus. Meanwhile, animals with tinnitus also manifested increased FLI in non-auditory brain structures that are involved in autonomic reactions, stress, arousal and attention. Electrophysiologically, we found that rats with tinnitus developed increased spontaneous firing in the auditory cortex (AC) and amygdala (AMG), as well as intra- and inter-AC and AMG neurosynchrony, which demonstrate that tinnitus may be actively produced and maintained by the interactions between the AC and AMG.
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Affiliation(s)
- Jinsheng Zhang
- Department of Otolaryngology-Head and Neck Surgery, Wayne State University, School of Medicine, 4201 Saint Antoine, Detroit, MI 48201, USA; Department of Communication Sciences & Disorders, Wayne State University, College of Liberal Arts & Sciences, 60 Farnsworth St., Detroit, MI 48202, USA.
| | - Hao Luo
- Department of Otolaryngology-Head and Neck Surgery, Wayne State University, School of Medicine, 4201 Saint Antoine, Detroit, MI 48201, USA
| | - Edward Pace
- Department of Otolaryngology-Head and Neck Surgery, Wayne State University, School of Medicine, 4201 Saint Antoine, Detroit, MI 48201, USA
| | - Liang Li
- Department of Psychology, McGovern Institute for Brain Research at PKU, Key Laboratory on Machine Perception (Ministry of Education), Peking University, Beijing, 100080, China
| | - Bin Liu
- Department of Otolaryngology-Head and Neck Surgery, Wayne State University, School of Medicine, 4201 Saint Antoine, Detroit, MI 48201, USA
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