Acid-Base Characteristics of Steady-State Exercise in Rats Adapted to Simulated Altitude

  • Norberto C. Gonzalez
  • Susan Dolezal
  • Richard L. Clancy
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 277)


Acclimation to altitude hypoxia results in adaptive changes which ultimately lead to an improvement in tissue oxygen delivery (for review, see Bouverot, 1985). Some of these adaptations produce changes in systems not directly related to oxygen transport. An example of this are the changes in the acid-base balance that follow prolonged exposure to altitude. The hyperventilation leads to hypocapnia and extra- and intracellular bicarbonate depletion (Freeman and Fenn, 1953, Olson and Dempsey, 1979, Bouverot, 1985, Gonzalez and Clancy, 1986 a,b) which tends to lower the buffer value of extra- and intracellular fluids. On the other hand, the increased hemoglobin concentration associated with hypoxia results in an increase in the non-bicarbonate buffer value of blood (Gonzalez and Clancy, 1986a). These features, coupled with differences in the rate of renal excretion of acid-base equivalents (Widener et al., 1986), modify the responses of hypoxia-adapted animals to challenges in the acid-base balance.


Blood Lactate Concentration Lactic Acid Concentration Simulated Altitude Prolonged Hypoxia Hypobaric Chamber 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Bouverot, P., 1985, Adaptation to Altitude Hypoxia in Vertebrates, Springer Verlag, Berlin.Google Scholar
  2. Bradley, A.F., M. Stupfel and J.W. Severinghaus, 1956, Effect of temperature on Pco2 and Po2 of blood in vitro,J. Appl.. Physiol, 9: 201–204.PubMedGoogle Scholar
  3. Cerretelli, P., 1980, Gas exchange in altitude, in: “Pulmonary Gas Exchange,” J.B. West, ed., Vol. II: Organism and Environment, pp. 97–147, Academic Press, New York.Google Scholar
  4. Flaim, S.F., Minteer, W.J., Clark, D.P. and Zelis, R., 1979, Cardiovascular response to acute aquatic and treadmill exercise in the untrained rat,J. Appl.. Physiol: Respir. Environm. Exercise Physiol, 46: 302–308.Google Scholar
  5. Freeman, J.W. and Fenn, W.O., 1953, Changes in carbon dioxide stores of rats due to atmospheres low in oxygen or rich in carbon dioxide, Am. J. Physiol, 174: 422–430.PubMedGoogle Scholar
  6. Fregosi, R.F. and Dempsey, J.A., 1984, Arterial blood acid-base regulation during exercise in rats,J. Appl. Physiol: Respir. Environm. Exercise Physiol, 57: 396–402.Google Scholar
  7. Gonzalez, N.C. and Clancy, R.L., 1986a, Acid-base regulation in prolonged hypoxia: Effects of increased Pco2, Respir. Physiol., 64: 213–22.PubMedCrossRefGoogle Scholar
  8. Gonzalez, N.C. and Clancy, R.L., 1986b, Intracellular pH regulation during prolonged hypoxia in rats, Respir. Physiol., 65: 331–339.PubMedCrossRefGoogle Scholar
  9. Hansen, J.E., Stelten, G.P. and Vogel, J.A., 1967, Arterial pyruvate, lactate, pH and Pco2 during work at sea level and at high altitude,J. Appl. Physiol., 23: 523–530.PubMedGoogle Scholar
  10. Laughlin, M.H. and Armstrong, R.B., 1982, Muscular blood flow distribution patterns as a function of running speed in rats, Am. J. Physiol. 243 (Heart Circ. Physiol. 12): H296–H306.PubMedGoogle Scholar
  11. Olson, E.B. and Dempsey, J.A., 1978, Rat as a model of humanlike ventilatory adaptation to chronic hypoxia, J. Appl. Physiol.: Respir. Environm. Exercise Physiol., 44: 763–769.Google Scholar
  12. Otis, A.B., 1964, Quantitative relationships in steady-state gas exchange, in: “Handbook of Physiology,” Section 3: Respiration, Vol. I., W.O. Fenn and H. Rann, ed., pp. 681–698, American Physiological Society, Washington, D.C.Google Scholar
  13. Parkhouse, W.S. and McKenzie, D.C., 1984, Possible contribution of skeletal muscle buffers to enhanced anaerobic performance: a brief review. Med. Sci. Sports Exerc, 16: 328–338.PubMedGoogle Scholar
  14. Pugh, L.G.C.E., Gill, M.B., Lahiri, S., Müledge, J.S., Ward, M.P. and West, J.B., 1964, Muscular exercise at great altitudes, J. Appl. Physiol., 19: 431–440.PubMedGoogle Scholar
  15. Wagner, P.D., Sutton, J.R., Reeves, J.T., Cymerman, A., Groves, B.M. and Malconian, M.K., 1987, Operation Everest II: Pulmonary gas exchange during a simulated ascent to Mount Everest,J. Appl. Physiol.: Respir. Environm. Exercise Physiol., 63: 2348–2359.Google Scholar
  16. West, J.B., Lahiri, S., GUI, M.B., Müledge, J.S., Pugh, L.G.C.E. and Ward, M.P., 1962, Arterial oxygen saturation during exercise at high altitude,J. Appl. Physiol., 17: 617–621.PubMedGoogle Scholar
  17. Widener, G., Sullivan, L.P., Clancy, R.L. and Gonzalez, N.C., 1986, Renal compensation of hypercapnia during prolonged hypoxia, Respir. Physiol., 65: 341–350.PubMedCrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • Norberto C. Gonzalez
    • 1
  • Susan Dolezal
    • 1
  • Richard L. Clancy
    • 1
  1. 1.Department of PhysiologyUniversity of Kansas Medical CenterKansas CityUSA

Personalised recommendations