Intrapulmonary Carbon Dioxide Sensitive Receptors: Amphibians to Mammals
Direct neural recordings have been made from intrapulmonary CO2-sensitive receptors in all classes of tetrapods. Specific characteristics of these receptors, such as their relative sensitivity to chemical (CO2, O2, and several drugs) and mechanical stimuli, the responsiveness to static and dynamic CO2 concentrations in their microenvironment, their location in the lung, and the influence of intracellular H+ in controlling their discharge have been studied in detail in some animals.
Amphibian lungs, as exemplified by the bullfrog, possess both rapidly and slowly adapting CO2-sensitive mechanoreceptors, but no receptors whose sole physiological stimulus is CO2 concentration. Reptilian lungs, at least in turtles and Tegu lizards, possess CO2-sensitive mechanoreceptors as well as receptors strikingly sensitive to CO2 but not to stretch of the lung. The CO2 receptors respond to static concentration of CO2 in the lungs as well as to rapid changes in intrapulmonary CO2 concentration. Avian lungs apparently possess only CO2 receptors without mechanical sensitivity. Mammalian lungs seemingly have only CO2-sensitive mechanoreceptors (slowly adapting pulmonary stretch receptors).
In all vertebrate classes studied, the discharge from both CO2 receptors and CO2-sensitive mechanoreceptors inhibits respiratory neuronal output from the brain. Intensive investigations in many laboratories are currently in progress to determine the importance of these receptors in controlling breathing.
Unable to display preview. Download preview PDF.
- Adrian, E.D.: Afferent impulses in the vagus and th eir effect on respiration. J. Physiol. (London) 79, 332–357 (1933)Google Scholar
- Banzett, R.B., Coleridge, H.M., Coleridge, J.C.G.: Effect of CO2 on pulmonary vagal afferents in dogs. Physiologist 19, 115 (1976)Google Scholar
- Barnas, G.M.: Relationship between the discharge of avian intrapulmonary CO2 receptors and bronchial smooth muscle contraction. M.S. thesis, Univ. Nebraska, Lincoln, Nebraska 1977Google Scholar
- Bartoli, A., Cross, B.A., Guz, A., Jain, S.K., Noble, M.I.M., Trenchard, D.W.: The effect of carbon dioxide in the airways and alveoli on ventilation; a vagal reflex studied in the dog. J. Physiol. (London) 240, 91–109 (1974)Google Scholar
- Bitensky, L., Chambers, D.J., Chayen, J., Cross, B.A., Guz, A., Jain, S.K., Johnston, J.J.: Evidence concerning the site of receptors mediating the Hering-Breuer inflation reflex. J. Physiol. (London) 249, 30–31 (1975)Google Scholar
- Boelaert, R.B.: Sur la physiologie de la respiration de lacentiens. Arch. Int. pharmacodyn. Ther. 51, 379–436 (1941)Google Scholar
- Sordoni, L.: Sull’apnea spermentale. Sperimentale 61, 113–132 (1888)Google Scholar
- Bradley, G.W., Noble, M.I.M., Trenchard, D.: The direct effect of pulmonary stretch receptor discharge produced by changing lung carbon dioxide concentration in dogs on cardiopulmonary bypass and its action on breathing. J. Physiol. (London) 261 359–373 (1976)Google Scholar
- Burger, R.E.: Pulmonary chemosensitivity in the domestic fowl. Federation Proc. 27, 328 (1968)Google Scholar
- Dickinson, C.J., Paintal, A.S.: Stimulation of type-J pulmonary receptors in the cat by carbon dioxide. Clin. Sci. 38, 33P (1970)Google Scholar
- Dooley, M.S., Koppanyi, T.: The control of respiration in the domestic duck (Anas. boscos). J. Pharmac. Exp. Ther. 36, 507–518 (1929)Google Scholar
- Downing, S.E., Torrance, R.W.: Vagal baroreceptors of the bull-frog. J. Physiol. (London) 156, 13P (1961)Google Scholar
- Duke, G.E., Kuhlmann, W.D., Fedde, M.R.: Evidence for mechanoreceptors in the muscular stomach of the chicken. Poultry Sci. 56, 297–299 (1977)Google Scholar
- Fedde, M.R., Burger, R.E., Kitchell, R.L.: Localization of vagal afferents involved in the maintenance of normal avian respiration. Poultry Sci. 42, 1224–1236 (1963)Google Scholar
- Fedde, M.R., Peterson, D.F.: Intrapulmonary receptor response to changes in airway- gas composition in Gallus domesticus. J. Physiol. (London) 209, 609–625 (1970)Google Scholar
- Foa, C.: Recherches sur l’apnée des oiseaux. Archs. ital. Biol. 55, 412–422 (1911)Google Scholar
- Molony, V.: A study of vagal afferent activity in phase with breathing and its role in the control of breathing in Gallus domesticus. Ph.D. thesis, Univ. Liverpool, Liverpool, England 1972Google Scholar
- Nielsen, B.: On the regulation of the respiration in reptiles. I. The effect of temperature and CO2 on the respiration of lizards (Lacerta). J. exp. Biol. 38, 301–314 (1961)Google Scholar
- Nye, P.C.G.: Stimulus-response relations and location of intrapulmonary chemoreceptors in the lung of Gallus domesticus. Ph.D. thesis, Univ. California, Davis, California 1977Google Scholar
- Osborne, J.L., Burger, R.E.: Static and dynamic response characteristics of CO2-sensitive chemoreceptors in the avian lung. Physiologist 14, 205 (1971)Google Scholar
- Perkins, J.F., Jr.: Historical development of respiratory physiology. In: Handbook of Physiology, Section 3, Respiration, Vol. I. Fenn, W.A., Rahn, H. (eds.). Washington, D.C.: Am. Physiol. Soc., 1964, pp. 1–62Google Scholar
- Saalfeld, E. von: Die nervöse Regulierung der Atembewegungen bei Uromastix. Pflügers Arch. ges. Physiol. 233 449–468 (1934)Google Scholar
- Smyth, D.H.: The central and reflex control of respiration in the frog. J. Physiol. (London) 95, 305–327 (1939)Google Scholar
- Templeton, J.R., Dawson, W.R.: Respiration in the lizard Crolophytus collaris. Physiol. Zool. 36, 104–121 (1963)Google Scholar