Neural Control of Respiration Pharmacology > Neuropsychiatric System > Neuropsychiatric System

Total Page:16

File Type:pdf, Size:1020Kb

Neural Control of Respiration Pharmacology > Neuropsychiatric System > Neuropsychiatric System Neural Control of Respiration Pharmacology > Neuropsychiatric System > Neuropsychiatric System NEURAL CONTROL OF RESPIRATION OVERVIEW Medulla • The medulla is the primary brainstem mediator of respiration. • Via the dorsal respiratory group (DRG), the dorsal (posterior) medulla controls sensory integration. - For its location, think: solitary tract nucleus. • Via the ventral respiratory group (VRG), the ventral (anterior) medulla controls motor output. - For its location, think: nucleus ambiguus. Phrenic nerve • C3, C4, C5 supply the phrenic nerve, which innervate the diaphragm: C3, C4, C5 "keep the diaphragm alive". BRAINSTEM CIRCUITRY Ventral respiratory group (VRG) • Within the medulla, anteriorly, lies the ventral respiratory group (VRG), which lies within the ventrolateral medulla. - It provides innervation for motor output. - It is involved in the activation of both inspiration and expiration. Dorsal respiratory group (DRG) • Within the dorsal medulla (in the solitary tract nucleus), lies the dorsal respiratory group (DRG). - It provides sensory integration. - It receives sensory input related to the inspiration phase of respiration. PERIPHERAL CHEMORECEPTORS Peripheral chemoreceptors act on the dorsal respiratory group 1 / 4 • Peripheral innervation involves the aortic bodies (shown here in the arch of the aorta) and the carotid bodies in the carotid bifurcation. - The carotid and aortic bodies are chemoreceptors. - They respond to levels of arterial oxygen and carbon dioxide levels and blood acidity. Innervation to the brainstem respiratory center • Both cranial nerves 9 and 10 (we treat them jointly for simplicity) pass through the jugular foramen within the skull base across from the brainstem to innervate the dorsal respiratory group. SECONDARY INSPIRATORY MUSCLES Key structures • Anterior face, tongue, pharynx, and larynx. Innervation • Cranial nerves 9, 10, and 12 innervate the secondary inspiratory muscles (again, we treat them jointly for simplicity). VRG innervation of CNs 9 and 10 • The ventral respiratory group acts upon these cranial nerves. PRIMARY INSPIRATORY MUSCLES Key structures • Thoracic cage, diaphragm, and intercostal muscles. Innervation • The ventral respiratory group innervates C3, C4, C5 motor neurons in the anterior horn of the spinal cord gray matter, which supply the phrenic nerve, which innervates the diaphragm (again: C3, C4, C5 "keep the diaphragm alive"). Intercostal nerves • Intercostal nerves innervate the intercostal muscles. DETAILED ANATOMY OF THE DRG & VRG Dorsal respiratory group (DRG) 2 / 4 • The dorsal respiratory group lies within the solitary tract nucleus of cranial nerves 9 and 10. Ventral respiratory group (VRG) Simplification of VRG microanatomy • First, add nucleus ambiguus of CNs 9 and 10. - This will help us continue to recall the important of CNs 9 and 10 and thus the medulla itself in respiratory control. • There are many subnuclei that constitute the ventral respiratory group; we'll only address the Bötzinger nuclei, here. • The Bötzinger complex lies within the superior aspect of the ventral respiratory group (some authors distinguish it from the ventral respiratory group, entirely). • The pre-Bötzinger complex is considered the "respiratory pacemaker." - Notably, it contains mu receptors, which makes it sensitive to opioids. - Thus, we can see one of the ways in which opioids (such as morphine) can depress our drive to breathe. CLINICAL CORRELATION: ONDINE'S CURSE • Ondine's curse is the clinical eponym for the failure of automatic breathing during sleep. - It typically occurs from lower medullary or high cervical spinal cord lesions. - These patients are dependent on a ventilator when they sleep to survive. PONTINE RESPIRATORY CONTROL CENTERS Apneustic center • The apneustic center is a nonspecific region in the posterior lower pons. - It promotes apneusis: a prolonged inspiratory pause. - It comprises diffuse lower pontine nuclei. Pneumotaxic center • The pneumotaxic center (aka the pontine respiratory group). - It prevents apneusis: it promotes regular breathing. - The pneumotaxic center comprises the medial parabrachial nucleus and the Kölliker-fuse nucleus. Functions Whereas these centers where formerly thought to be well-defined and to perform unique functions, now they are understood to be diffuse and their functions are no longer thought to be unique (the pneumotaxic center is not the only 3 / 4 site to prevent apneusis, for instance*). BREATHING PATTERNS We can use breathing patterns in comatose patients to localize the level of the CNS lesion, as follows: Patterns • Cerebral hemispheric lesions cause Cheyne-Stokes respirations. – Illustrate Cheyne-Stokes respirations as periods of hyperpnea (deep breathing) with apneas (cessation of breathing) • Midbrain lesions cause hyperventilation. - Illustrate hyperventilation as rapid, deep breathing. • High pontine lesions cause apneustic breathing. - Illustrate apneustic breathing as periods of long inspiratory pauses before release of air. • Low pontine lesions cause cluster breathing. - Illustrate cluster breathing as irregular clusters of breaths. • Medullary lesions cause ataxic breathing. - Illustrate ataxic breathing as a completely irregular breathing pattern. Limitations • Although these localizations are notoriously unreliable, they still give us a simple heuristic to follow when we examine comatose patients, which is essential. Powered by TCPDF (www.tcpdf.org) 4 / 4.
Recommended publications
  • Hypoxia and Hypercapnia: Sensory and Effector Mechanisms
    ISSN: 2574-1241 Volume 5- Issue 4: 2018 DOI: 10.26717/BJSTR.2018.08.001692 Kulchitsky Vladimir. Biomed J Sci & Tech Res Opinion Open Access Hypoxia and Hypercapnia: Sensory and Effector Mechanisms Kulchitsky Vladimir1*, Zamaro Alexandra1 and Koulchitsky Stanislav2 1Institute of Physiology, National Academy of Sciences, Minsk, Belarus, Europe 2Liege University, Liege, Belgium, Europe Received: Published: *Corresponding September author: 03, 2018; September 05, 2018 Kulchitsky Vladimir, Institute of Physiology, National Academy of Sciences, Minsk, Belarus, Europe Keywords: + Abbreviations:Central Chemoreceptors; Peripheral Chemoreceptors;2 Regulation of Respiration2 ATP: Adenosine Triphosphate; CО : Carbon Dioxide; H : Hydrogen Ions; О : Oxygen Introduction Human life is determined by plenty of factors, and normal Central and Peripheral Mechanisms of Breathing oxygen environment is one of the most important. Mammals and Regulation These receptors are located in blood vessels and tissues and in situations when discrepancy between amount of arriving O and human have obtained specific receptors during the evolution. Which mechanism helps living organism make timely decisions2 react on hypoxic stimulus [1-3]. Arterial system has the highest energy needs in brain’s nerve tissue develops? The mechanism of density of peripheral chemoreceptors which react on oxygen + precise control of carbon dioxide (CO2) and hydrogen ions (H ) - but (O ) content change in the internal milieu [1]. Chemoreceptors 2 not O2- in brain tissue has been evolutionally chosen. Such receptor located in carotid body in the area of carotid arteries bifurcation mechanisms (central chemoreceptors) were formed close to neural heads via carotid and vertebral arteries to brain, and strategically are the most important [2-5]. Significant part of cardiac output vital localization of those receptors in carotid body allows them networks of respiratory center - at caudal brain stem [7-9].
    [Show full text]
  • For Pneumograph
    For Pneumograph: Central chemoreceptors are primarily sensitive to changes in the pH in the blood, (resulting from changes in the levels of carbon dioxide) and they are located on the medulla oblongata near to the medullar respiratory groups of the respiratory center (1. Pneumotaxic center - various nuclei of the pons and 2. Apneustic center -nucleus of the pons). The peripheral chemoreceptors that detect changes in the levels of oxygen and carbon dioxide are located in the arterial aortic bodies and the carotid bodies. Information from the peripheral chemoreceptors is conveyed along nerves to the respiratory groups of the respiratory center. There are four respiratory groups, two in the medulla and two in the pons. From the respiratory center, the muscles of respiration, in particular the diaphragm, are activated to cause air to move in and out of the lungs. Hyperventilation: When a healthy person takes several deep and fast breaths (hyperventilation), PCO2 in the lungs and blood falls. As a result there is an increase in diffusion of CO2 to the alveolar air from dissolved state in blood. As the conc. of H2CO3 is in equilibrium with that of dissolved CO2 in blood, hyperventilation increases the [HCO3]/ [H2CO3] ratio by falling of CO2 conc. Thus there is a rise of blood pH (greater than pH 7.4). The breathing centre detects this change and stops or reduces stimulation and work of the respiratory muscles (called apnea). (Blood leaving the lungs is normally fully saturated with oxygen, so hyperventilation of normal air cannot increase the amount of oxygen available.) Breath-holding: The person naturally holds their breath until the CO2 level reaches the initially pre- set value.
    [Show full text]
  • Regulation of Respiration
    Regulation of respiration Breathing is controlled by the central neuronal network to meet the metabolic ddfthbddemands of the body – Neural regulation – Chemical regulation Respiratory center Definition: – A collection of functionally similar neurons that help to regulate the respiratory movement Respiratory center Medulla Basic respiratory center: produce and control the respiratory Pons rhythm Higher respiratory center: cerebral cortex, hypotha la mus & limb ic syste m Spinal cord: motor neurons Neural regulation of respiration Voluntary breathing center – Cerebral cortex Automatic (involuntary) breathing center – Medulla – Pons Neural generation of rhythmical breathing The discharge of medullary inspiratory neurons provides rhythmic input to the motor neurons innervating the inspiratory muscles. Then the action pottiltential cease, the inspiratory muscles relax, and expiration occurs as the elastic lungs recoil. Inspiratory neurons Exppyiratory neurons Respiratory center Dorsal respiratory group (medulla) – mainly causes inspiration Ventral respiratory group (medulla) – causes either exp itiiration or insp itiiration Pneumotaxic center ((pppupper pons ) – inhibits apneustic center & inhibits inspiration,helps control the rate and pattern of breathing Apneustic center (lower pons) – to promote inspiration Hering-Breuer inflation reflex (Pulmonary stretch reflex) The reflex is originated in the lungs and media te d by the fibers o f the vagus nerve: – Pulmonary inflation reflex: inflation of the lungs, eliciting expiration.
    [Show full text]
  • Math1 Is Essential for the Development of Hindbrain Neurons Critical for Perinatal Breathing
    Neuron Article Math1 Is Essential for the Development of Hindbrain Neurons Critical for Perinatal Breathing Matthew F. Rose,1,7 Jun Ren,6,7 Kaashif A. Ahmad,2,7 Hsiao-Tuan Chao,3 Tiemo J. Klisch,4,5 Adriano Flora,4 John J. Greer,6 and Huda Y. Zoghbi1,2,3,4,5,* 1Program in Developmental Biology 2Department of Pediatrics 3Department of Neuroscience 4Department of Molecular and Human Genetics 5Howard Hughes Medical Institute Baylor College of Medicine, Houston, TX 77030, USA 6Department of Physiology, University of Alberta, Edmonton, Canada 7These authors contributed equally to this work *Correspondence: [email protected] DOI 10.1016/j.neuron.2009.10.023 SUMMARY died of SIDS appear to have been unable to arouse from sleep in response to hypoxia (Kato et al., 2003). A more complete Mice lacking the proneural transcription factor Math1 understanding of the respiratory network in the hindbrain could (Atoh1) lack multiple neurons of the proprioceptive provide insight into the pathogenesis of these disorders. and arousal systems and die shortly after birth from Respiratory rhythm-generating neurons reside within the an apparent inability to initiate respiration. We ventral respiratory column (VRC) of the medulla. The pre-Bo¨ t- sought to determine whether Math1 was necessary zinger complex (preBo¨ tC) generates the inspiratory rhythm for the development of hindbrain nuclei involved in (Smith et al., 1991) and receives modulatory input from adjacent nuclei, including a region located around the facial motor nucleus respiratory rhythm generation, such as the parafacial just rostral to the preBo¨ tC. Different investigators refer to respiratory group/retrotrapezoid nucleus (pFRG/ neurons in this region either as the parafacial respiratory group RTN), defects in which are associated with congen- (pFRG) or as the retrotrapezoid nucleus (RTN).
    [Show full text]
  • Integrative Actions of the Reticular Formation the Reticular Activating System, Autonomic Mechanisms and Visceral Control
    University of Nebraska Medical Center DigitalCommons@UNMC MD Theses Special Collections 5-1-1964 Integrative actions of the reticular formation The reticular activating system, autonomic mechanisms and visceral control George A. Young University of Nebraska Medical Center This manuscript is historical in nature and may not reflect current medical research and practice. Search PubMed for current research. Follow this and additional works at: https://digitalcommons.unmc.edu/mdtheses Part of the Medical Education Commons Recommended Citation Young, George A., "Integrative actions of the reticular formation The reticular activating system, autonomic mechanisms and visceral control" (1964). MD Theses. 69. https://digitalcommons.unmc.edu/mdtheses/69 This Thesis is brought to you for free and open access by the Special Collections at DigitalCommons@UNMC. It has been accepted for inclusion in MD Theses by an authorized administrator of DigitalCommons@UNMC. For more information, please contact [email protected]. THE INTEGRATIVE ACTIONS OF THE RETICULAR FORlVIATION The Reticular Activating System, Autonomic Mechanisms and Visceral Control George A. Young 111 Submitted in Partial Fulfillment for the Degree of Doctor of Medicine College of Medicine, University of Nebraska February 3, 1964 Omaha, Nebraska TABLE OF CONTENTS Page I. Introduction. ~4'~ •••••••••••• *"' ••• " ••• "' ••• 1I •• 1 II. The Reticula.r Activa.ting System (a) Historical Review •••.....•..•.•. · ••••• 5 (1) The Original Paper~ ..•.••...••.••••. 8 (2) Proof For a R.A.S •.•...•.....•••.• ll (b) ,The Developing Concept of the R.A.S ••• 14 (1) R.A.S. Afferents •..•.•......••..• 14 (2) The Thalamic R.F •••.••.......••.••. 16 (3) Local Cortical Arousal •••••••.•.••• 18 (4) The Hypothalamus end the R.A.S ••••• 21 (5) A Reticular Desynchronizing System.
    [Show full text]
  • Brainstem Dysfunction in Critically Ill Patients
    Benghanem et al. Critical Care (2020) 24:5 https://doi.org/10.1186/s13054-019-2718-9 REVIEW Open Access Brainstem dysfunction in critically ill patients Sarah Benghanem1,2 , Aurélien Mazeraud3,4, Eric Azabou5, Vibol Chhor6, Cassia Righy Shinotsuka7,8, Jan Claassen9, Benjamin Rohaut1,9,10† and Tarek Sharshar3,4*† Abstract The brainstem conveys sensory and motor inputs between the spinal cord and the brain, and contains nuclei of the cranial nerves. It controls the sleep-wake cycle and vital functions via the ascending reticular activating system and the autonomic nuclei, respectively. Brainstem dysfunction may lead to sensory and motor deficits, cranial nerve palsies, impairment of consciousness, dysautonomia, and respiratory failure. The brainstem is prone to various primary and secondary insults, resulting in acute or chronic dysfunction. Of particular importance for characterizing brainstem dysfunction and identifying the underlying etiology are a detailed clinical examination, MRI, neurophysiologic tests such as brainstem auditory evoked potentials, and an analysis of the cerebrospinal fluid. Detection of brainstem dysfunction is challenging but of utmost importance in comatose and deeply sedated patients both to guide therapy and to support outcome prediction. In the present review, we summarize the neuroanatomy, clinical syndromes, and diagnostic techniques of critical illness-associated brainstem dysfunction for the critical care setting. Keywords: Brainstem dysfunction, Brain injured patients, Intensive care unit, Sedation, Brainstem
    [Show full text]
  • Brainstem Dysfunction in Critically Ill Patients
    Benghanem et al. Critical Care (2020) 24:5 https://doi.org/10.1186/s13054-019-2718-9 REVIEW Open Access Brainstem dysfunction in critically ill patients Sarah Benghanem1,2 , Aurélien Mazeraud3,4, Eric Azabou5, Vibol Chhor6, Cassia Righy Shinotsuka7,8, Jan Claassen9, Benjamin Rohaut1,9,10† and Tarek Sharshar3,4*† Abstract The brainstem conveys sensory and motor inputs between the spinal cord and the brain, and contains nuclei of the cranial nerves. It controls the sleep-wake cycle and vital functions via the ascending reticular activating system and the autonomic nuclei, respectively. Brainstem dysfunction may lead to sensory and motor deficits, cranial nerve palsies, impairment of consciousness, dysautonomia, and respiratory failure. The brainstem is prone to various primary and secondary insults, resulting in acute or chronic dysfunction. Of particular importance for characterizing brainstem dysfunction and identifying the underlying etiology are a detailed clinical examination, MRI, neurophysiologic tests such as brainstem auditory evoked potentials, and an analysis of the cerebrospinal fluid. Detection of brainstem dysfunction is challenging but of utmost importance in comatose and deeply sedated patients both to guide therapy and to support outcome prediction. In the present review, we summarize the neuroanatomy, clinical syndromes, and diagnostic techniques of critical illness-associated brainstem dysfunction for the critical care setting. Keywords: Brainstem dysfunction, Brain injured patients, Intensive care unit, Sedation, Brainstem
    [Show full text]
  • The Respiratory Control Mechanisms in the Brainstem and Spinal Cord: Integrative Views of the Neuroanatomy and Neurophysiology
    J Physiol Sci (2017) 67:45–62 DOI 10.1007/s12576-016-0475-y REVIEW The respiratory control mechanisms in the brainstem and spinal cord: integrative views of the neuroanatomy and neurophysiology 1 2 3 4 Keiko Ikeda • Kiyoshi Kawakami • Hiroshi Onimaru • Yasumasa Okada • 5 6 7 3 Shigefumi Yokota • Naohiro Koshiya • Yoshitaka Oku • Makito Iizuka • Hidehiko Koizumi6 Received: 15 March 2016 / Accepted: 22 July 2016 / Published online: 17 August 2016 Ó The Physiological Society of Japan and Springer Japan 2016 Abstract Respiratory activities are produced by medullary Introduction respiratory rhythm generators and are modulated from various sites in the lower brainstem, and which are then Respiration is crucial for animal survival. In the last 10 output as motor activities through premotor efferent net- years, the cytoarchitecture of the respiratory control center works in the brainstem and spinal cord. Over the past few has been analyzed at the single-cell and genetic levels. The decades, new knowledge has been accumulated on the respiratory center is located in the medulla oblongata and is anatomical and physiological mechanisms underlying the involved in the minute-to-minute control of breathing. generation and regulation of respiratory rhythm. In this Unlike the cardiac system, respiratory rhythm is not pro- review, we focus on the recent findings and attempt to duced by a homogeneous population of pacemaker cells. elucidate the anatomical and functional mechanisms Rather, it can be explained with two oscillators: the underlying respiratory control in the lower brainstem and parafacial respiratory group (pFRG; Sect. 1) and the pre- spinal cord. Bo¨tzinger complex (preBo¨tC, inspiratory pacemaker pop- ulation; Sects.
    [Show full text]
  • SAY: Welcome to Module 1: Anatomy & Physiology of the Brain. This
    12/19/2018 11:00 AM FOUNDATIONAL LEARNING SYSTEM 092892-181219 © Johnson & Johnson Servicesv Inc. 2018 All rights reserved. 1 SAY: Welcome to Module 1: Anatomy & Physiology of the Brain. This module will strengthen your understanding of basic neuroanatomy, neurovasculature, and functional roles of specific brain regions. 1 12/19/2018 11:00 AM Lesson 1: Introduction to the Brain The brain is a dense organ with various functional units. Understanding the anatomy of the brain can be aided by looking at it from different organizational layers. In this lesson, we’ll discuss the principle brain regions, layers of the brain, and lobes of the brain, as well as common terms used to orient neuroanatomical discussions. 2 SAY: The brain is a dense organ with various functional units. Understanding the anatomy of the brain can be aided by looking at it from different organizational layers. (Purves 2012/p717/para1) In this lesson, we’ll explore these organizational layers by discussing the principle brain regions, layers of the brain, and lobes of the brain. We’ll also discuss the terms used by scientists and healthcare providers to orient neuroanatomical discussions. 2 12/19/2018 11:00 AM Lesson 1: Learning Objectives • Define terms used to specify neuroanatomical locations • Recall the 4 principle regions of the brain • Identify the 3 layers of the brain and their relative location • Match each of the 4 lobes of the brain with their respective functions 3 SAY: Please take a moment to review the learning objectives for this lesson. 3 12/19/2018 11:00 AM Directional Terms Used in Anatomy 4 SAY: Specific directional terms are used when specifying the location of a structure or area of the brain.
    [Show full text]
  • Noeud Vital and the Respiratory Centers Eelco F
    Neurocrit Care (2019) 31:211–215 https://doi.org/10.1007/s12028-019-00686-8 NEUROCRITICAL CARE THROUGH HISTORY Noeud Vital and the Respiratory Centers Eelco F. M. Wijdicks* © 2019 Springer Science+Business Media, LLC, part of Springer Nature and Neurocritical Care Society Abstract We now recognize that the main breathing generator resides principally in the medulla oblongata. Vivisectionists— specifcally, Julien Legallois—discovered “the respiratory center.” Cutting through the brainstem stops respiration but not if the medulla remains intact and the brain is sliced in successive portions. Pierre Flourens localized surgical ablation experiments further identifed a 1-mm area in the medulla, which he called vital knot or node (noeud vital). Detailed characterization had to wait until the 1920s, when Lumsden carried out more specifc transection experi- ments to improve morphological diferentiation of the respiratory center into inspiratory and expiratory divisions. Keywords: Noeud vital, Respiratory centers, Brainstem, Animal research Te respiratory center in the brainstem and its three result of vivisection experiments undertaken to discover classes of neural mechanisms (the chemorefexes, the the structures (and organs) needed to sustain life [1]. His central drive, and neuronal feedback from the muscles of decapitation experiments involved a heart–lung prepara- respiration) were identifed and characterized in fts and tion ligating the inferior vena cava, aorta, carotid arter- starts in the late 1800s and early 1900s. Te regulation ies, and jugular vein while ventilating the lungs through of PaCO2 at a physiologic set point maintains vigilance, a syringe inserted in a decapitated rabbit (Fig. 1) [1]. which changes with large increases in PaCO2.
    [Show full text]
  • Introduction to the Respiratory System
    C h a p t e r 15 The Respiratory System PowerPoint® Lecture Slides prepared by Jason LaPres Lone Star College - North Harris Copyright © 2010 Pearson Education, Inc. Copyright © 2010 Pearson Education, Inc. Introduction to the Respiratory System • The Respiratory System – Cells produce energy: • For maintenance, growth, defense, and division • Through mechanisms that use oxygen and produce carbon dioxide Copyright © 2010 Pearson Education, Inc. Introduction to the Respiratory System • Oxygen – Is obtained from the air by diffusion across delicate exchange surfaces of the lungs – Is carried to cells by the cardiovascular system, which also returns carbon dioxide to the lungs Copyright © 2010 Pearson Education, Inc. 15-1 The respiratory system, composed of conducting and respiratory portions, has several basic functions Copyright © 2010 Pearson Education, Inc. Functions of the Respiratory System • Provides extensive gas exchange surface area between air and circulating blood • Moves air to and from exchange surfaces of lungs • Protects respiratory surfaces from outside environment • Produces sounds • Participates in olfactory sense Copyright © 2010 Pearson Education, Inc. Components of the Respiratory System • The Respiratory Tract – Consists of a conducting portion • From nasal cavity to terminal bronchioles – Consists of a respiratory portion • The respiratory bronchioles and alveoli The Respiratory Tract Copyright © 2010 Pearson Education, Inc. Components of the Respiratory System • Alveoli – Are air-filled pockets within the lungs:
    [Show full text]
  • Regulation of Ventilation
    CHAPTER 1 Regulation of Ventilation © IT Stock/Polka Dot/ inkstock Chapter Objectives By studying this chapter, you should be able to do 5. Describe the chemoreceptor input to the brain the following: stem and how it modifi es the rate and depth of breathing. 1. Describe the brain stem structures that regulate 6. Explain why it is that the arterial gases and pH respiration. do not signifi cantly change during moderate 2. Defi ne central and peripheral chemoreceptors. exercise. 3. Explain what eff ect a decrease in blood pH or 7. Discuss the respiratory muscles at rest and carbon dioxide has on respiratory rate. during exercise. How are they infl uenced by 4. Describe the Hering–Breuer reflex and its endurance training? function. 8. Describe respiratory adaptations that occur in response to athletic training. Chapter Outline Passive and Active Expiration Eff ects of Blood PCO 2 and pH on Ventilation Respiratory Areas in the Brain Stem Proprioceptive Refl exes Dorsal Respiratory Group Other Factors Ventral Respiratory Group Hering–Breuer Refl ex Apneustic Center Ventilation Response During Exercise Pneumotaxic Center Ventilation Equivalent for Oxygen () V/EOV 2 Chemoreceptors Ventilation Equivalent for Carbon Dioxide Central Chemoreceptors ()V/ECV O2 Peripheral Chemoreceptors Ventilation Limitations to Exercise Eff ects of Blood PO 2 on Ventilation Energy Cost of Breathing Ventilation Control During Exercise Chemical Factors Copyright ©2014 Jones & Bartlett Learning, LLC, an Ascend Learning Company Content not final. Not for sale or distribution. 17097_CH01_Pass4.indd 3 10/12/12 2:13 PM 4 Chapter 1 Regulation of Ventilation Passive and Active Expiration Ventilation is controlled by a complex cyclic neural process within the respiratory Brain stem Th e lower part centers located in the medulla oblongata of the brain stem .
    [Show full text]