The Effect of Middle Cardiac Nerve Stimulation Upon the Respiratory Response to \({\operatorname{Pa} _{{{\operatorname{CO} }_2}}}\) in the Chicken

  • J. A. Estavillo
  • M. L. Youther
Part of the Proceedings in Life Sciences book series (LIFE SCIENCES)


Respiratory movements in 13 thoracotomized cockerels were recorded. The pulmonary circulation of the right lung was blocked, and the left perfused lung was denervated in order to determine the effects on respiratory movements of intrapulmonary CO2 tension,\({\operatorname{P} _{{{\operatorname{iCO} }_2}}}\), arterial CO2 tension (\({\operatorname{P} _{{{\operatorname{aCO} }_2}}}\)) and electrical stimulation of the left middle carciac nerve. At low \({\operatorname{P} _{{{\operatorname{iCO} }_2}}}\) respiratory movements changed little with varying \({\operatorname{P} _{{{\operatorname{aCO} }_2}}}\) ; conversely, at low \({\operatorname{P} _{{{\operatorname{aCO} }_2}}}\) respiratory movements changed little with varying \({\operatorname{P} _{{{\operatorname{aCO} }_2}}}\) . At 70-torr \({\operatorname{P} _{{{\operatorname{aCO} }_2}}}\), respiratory movements were maximal at \({\operatorname{P} _{{{\operatorname{iCO} }_2}}}\) of 33 torr or higher. Stimulation of the middle cardiac nerve (MCN) produced a reduction in respiratory movements at most levels but showed greater sensitivity at low intrapulmonary \({\operatorname{P} _{{{\operatorname{iCO} }_2}}}\) and \({\operatorname{P} _{{{\operatorname{aCO} }_2}}}\) levels. Receptors with axons in the MCN may be important in the control of avian respiration.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Banzett, R.B., Burger, R.E.: Response of avian intrapulmonary chemoreceptors to venous CO2 and ventialtory gas flow. Respir. Physiol. 29, 63–72 (1977)Google Scholar
  2. Burger, R.E., Osborne, J.L., Banzett, R.B.: Intrapulmonary chemoreceptors in Gallus domesticus: adequate stimulus and functional localization. Respir. Physiol. 22, 87–97 (1974)PubMedCrossRefGoogle Scholar
  3. Estavillo, J.A.: Fiber size and sensory endings of the middle cardiac nerve of the domestic fowl Gallus domesticus. Acta Anatomica in press (1977)Google Scholar
  4. Estavillo, J.A., Burger, R.E.: Cardiac afferent activity in the depressor nerve of the chicken. J. Appl. Physiol. 225, 1063–1066 (1973a)Google Scholar
  5. Estavillo, J.A., Burger, R.E.: Avain cardiac receptors: activity changes by blood pressure, carbon dioxide and pH. J. Appl. Physiol. 225, 1067–1071 (1973b)Google Scholar
  6. Estavillo, J.A., Youther, M.L., Burger, R.E.: Respiratory control by the middle cardiac nerve in the chicken: effects of blood pressure. Respir. Physiol. submitted (1977)Google Scholar
  7. Jones, D.R.: The control of breathing in birds with particular reference to the initiation and maintenance of diving apnea. Federation Proc. 35, 1975–1982 (1976)Google Scholar
  8. Kostreva, D.R., Czarnecki, D., Zuperku, E.J., Cook, R.L., Kampine, J.P.: Cardiac vagal afferent reflex alteration of respiratory drive. Federation Proc. 36, 489 (1977)Google Scholar
  9. Kuhlman, W.D., Fedde, M.R.: Upper respiratory dead space in the chicken, its frac-tion of tidal volume. Comp. Biochem. and Physiol. 54A, 409–411 (1976)CrossRefGoogle Scholar
  10. Peterson, D.F., Nightingale, T.E.: Functional significance of thoracic vagal branches in the chickens. Respir. Physiol. 27, 267–275 (1976)PubMedCrossRefGoogle Scholar
  11. Ray, P.J., Fedde, M.R.: Responses to alterations in respiratory \({\operatorname{P} _{{{\operatorname{o} }_2}}}\) and \({\operatorname{P} _{{{\operatorname{co} }_2}}}\) in the chicken. Respir. Physiol. 6, 135–143 (1969)PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1978

Authors and Affiliations

  • J. A. Estavillo
    • 1
  • M. L. Youther
    • 1
  1. 1.Department of Basic Medical Education, School of MedicineSouthern Illinois UniversityCarbondaleUSA

Personalised recommendations