Although much is known about the control of both cardiac output and pulmonary ventilation, the mechanisms which precisely match both responses to the metabolic demands of exercise remain incompletely understood. These mechanisms are known to involve an interaction of feed-back and feed-forward (command signal) pathways. To obtain further insight into this interaction, this project is designed to study the degree of cardiopulmonary control coupling associated with the major mechanical changes present during normal exercise. In particular, the effect of the feed- forward drop in lung functional residual capacity (FRC) will be studied in terms of the cardiopulmonary reflexes involved in the awake dog. The basic question to be answered is whether this feed-forward lung volume pathway in combination with the known feed-back mechanisms can explain exercise responses. The role played by vagal afferents in mediating these responses will be determined by reversible cold block in awake dog.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL016390-19
Application #
3335206
Study Section
Respiratory and Applied Physiology Study Section (RAP)
Project Start
1977-01-01
Project End
1994-03-31
Budget Start
1992-04-01
Budget End
1994-03-31
Support Year
19
Fiscal Year
1992
Total Cost
Indirect Cost
Name
University of Southern California
Department
Type
Schools of Engineering
DUNS #
041544081
City
Los Angeles
State
CA
Country
United States
Zip Code
90089
Cha, E J; Chow, E; Vega, D M et al. (1988) Automated temperature control system for vagal cooling. J Appl Physiol 65:469-72
Chow, E; Cha, E J; Yamashiro, S M (1988) Ventilatory responses to increased blood flow and decreased lung volume in awake dogs. J Appl Physiol 65:714-20
Cha, E J; Chow, E; Chang, H K et al. (1988) Lung hyperinflation in isolated dog lungs during high-frequency oscillation. J Appl Physiol 65:1172-9
Hwang, W W; Yamashiro, S M; Sedlock, D et al. (1988) Ventilatory response to CO2 and O2 near eupnea in awake dogs. J Appl Physiol 65:788-96
Lin, C K; Levenson, H; Yamashiro, S M (1987) Optimization of coronary blood flow during cardiopulmonary resuscitation (CPR). IEEE Trans Biomed Eng 34:473-81
Ghazanshahi, S D; Yamashiro, S M; Marmarelis, V Z (1987) Use of a random forcing for high-frequency ventilation. J Appl Physiol 62:1201-5
Cha, E J; Sedlock, D; Yamashiro, S M (1987) Changes in lung volume and breathing pattern during exercise and CO2 inhalation in humans. J Appl Physiol 62:1544-50