Impulse activity in afferent vagal C-fibres with endings in the intrapulmonary airways of dogs

https://doi.org/10.1016/0034-5687(77)90086-XGet rights and content

Abstract

We recorded impulses from afferent vagal C-fibres (conduction velocities 0.8–2.4 m/sec) arising from endings in the lungs of anesthetized dogs with open chest. Endings were of two types (‘pulmonary’ and ‘bronchial’) distinguished by their response and accessibility to capsaicin and phenyl diguanide injected into the right or left atrium. ‘Pulmonary’ endings, stimulated only by capsaicin and accessible through the pulmonary circulation, have been described previously. ‘Bronchial’ endings were stimulated by both capsaicin and phenyl diguanide and were accessible through the bronchial circulation. Eight of 28 ‘bronchial’ endings were located in large airways within 4 cm of the hilum, and two were in small airways near the edge of the lung. The precise location of the remaining ‘bronchial’ endings was not determined but we think that many were in the airways. ‘Bronchial’ endings had a sparse and irregular spontaneous discharge. They were stimulated by the inhalation of 5% histamine aerosol, the evoked discharge having no obvious relation to the phase of ventilation. A few were weakly stimulated by hyperinflating the lungs; deflation was without effect. The function of these endings is unknown.

References (25)

  • D.J. Armstrong et al.

    A comparative study of irritant and type J receptors in the cat

    Respir. Physiol.

    (1974)
  • H.M. Coleridge et al.

    The effect of four volatile anaesthetic agents on the impulse activity of two types of pulmonary receptor

    Brit. J. Anaest.

    (1968)
  • S.R. Sampson et al.

    Properties of ‘irritant’ receptors in canine lung

    Respir. Physiol.

    (1975)
  • E. Agostoni et al.

    Functional and histological studies of the vagus nerve and its branches to the heart, lungs and abdominal viscera in the cat

    J. Physiol.(London)

    (1957)
  • H.M. Coleridge et al.

    Role of the pulmonary arterial baroreceptors in the effects produced by capsaicin in the dog

    J. Physiol. (London)

    (1964)
  • H.M. Coleridge et al.

    Pulmonary afferent fibres of small diameter stimulated by capsaicin and by hyperinflation of the lungs

    J. Physiol. (London)

    (1965)
  • H.M. Coleridge et al.

    Impulses in slowly conducting vagal fibers from afferent endings in the veins, atria, and arteries of dogs and cats

    Circulat. Res.

    (1973)
  • H.M. Coleridge et al.

    Afferent vagal C-fibers in the dog lung: their discharge during spontaneous breathing, and their stimulation by alloxan and pulmonary congestion

  • I.de B. Daly et al.

    Pulmonary and Bronchial Vascular Systems

    (1966)
  • G.S. Dawes et al.

    Respiratory and cardiovascular reflexes from the heart and lungs

    J. Physiol. (London)

    (1951)
  • G.S. Dawes et al.

    Chemoreceptor reflexes in the dog and the action of phenyl diguanide

    Arch. Int. Pharmacodyn. Ther.

    (1952)
  • M. Fillenz et al.

    Receptors of the lungs and airways

  • Cited by (163)

    • Neurokinin 1 and 2 receptors are involved in PGE<inf>2</inf>- and citric acid-induced cough and ventilatory responses

      2022, Respiratory Physiology and Neurobiology
      Citation Excerpt :

      Exposure to aerosolized citric acid (CA) or capsaicin (CAP) provokes individual loud coughs (Type I), while prostaglandin E2 (PGE2) induces bouts of smaller coughing with a weak coughing sound (Type II). Type I and II coughs are evoked primarily by stimulation of transient receptor potential cation channel subfamily V member 1 (TRPV1) and EP3 (a PGE2 receptor) of bronchopulmonary C-fibers (PCFs) respectively (Coleridge and Coleridge, 1977; Forsberg et al., 1988; Gao et al., 2021; Lalloo et al., 1995; Satoh et al., 1993). PCFs contain tachykinin neuropeptides, including substance P (SP) and neurokinin A (NKA) (Lee et al., 2013; Lundberg et al., 1984).

    • Abraham Guz memorial: Still unresolved hypotheses: Lung reflexes and perceptions of breathing

      2015, Respiratory Physiology and Neurobiology
      Citation Excerpt :

      Those in the larger bronchi are more chemosensitive; they may cause cough, but also stimulate hyperventilation, augmented breaths (as in Head’s paradoxical reflex), mucus secretion, bronchoconstriction and laryngeal closure. The third group of vagal lung afferents to be considered are the J (juxtacapillary) receptors which transmit impulses through the unmyelinated, slowly conducting C fibres of the afferent vagus (Paintal, 1953; Coleridge and Coleridge, 1977, 1984). Why juxtacapillary?

    • Peripheral neural circuitry in cough

      2015, Current Opinion in Pharmacology
    View all citing articles on Scopus

    This work was supported by U.S. Public Health Service Grants HL-13875 and HL-06285 from the National Heart and Lung Institute.

    View full text