Journal of Applied Physiology, Vol 42, Issue 3 403-407, Copyright © 1977 by American Physiological Society

ARTICLES

Cardiovascular, respiratory, and metabolic adjustments to exercise in dogs

J. A. Wagner, S. M. Horvath and T. E. Dahms

Cardiovascular and metabolic parameters were studied in dogs anesthetized with pentobarbital sodium, and while awake resting or exercising for 30 min at either 6.4 km/h, 10% grade (32% VO2 max) or 8.0 km/h, 16% grade (50% VO2 max). The anesthetized dogs had lower cardiac outputs, stroke volumes, arterial-mixed venous oxygen differences, oxygen uptakes, rectal temperatures, and higher diastolic and mean arterial pressures than awake resting dogs. Heart rates and arterial systolic pressures were similar in the two conditions. The increased oxygen uptakes during exercise were associated with approximately equal percentage increments in cardiac outputs and oxygen extractions. Cardiac output increases during exercise were largely due to increases in heart rates. Arterial CO2 tension and CO2 contents as well as venous O2 and CO2 gas tensions and contents declined, and pH and rectal temperatures increased during exercise. The dogs became alkalotic during exercise. Elevated central body temperatures appeared to be the major factor controlling respiration.

This article has been cited by other articles:

				P. L. Entin, D. Robertshaw, and R. E. Rawson Thermal drive contributes to hyperventilation during exercise in sheep J Appl Physiol, July 1, 1998; 85(1): 318 - 325. [Abstract] [Full Text] [PDF]

				C. M. Montefusco, S. Feinstein, T. Sabita Rao, and F. J. Veith Pulmonary and Hemodynamic Function in Dogs During Exercise: Effects of Lung Autotransplantation Angiology, May 1, 1983; 34(5): 340 - 354. [Abstract] [PDF]