TY - JOUR
T1 - Ventilatory response to carbon monoxide during exercise in hypoxia and hypercapnia
AU - Crocker, George H.
AU - Kwon, Jenny
AU - Kass, Philip H
AU - Jones, James H
PY - 2017/12/1
Y1 - 2017/12/1
N2 - We tested if the addition of CO to inspired gases with different inspired O2 and CO2 fractions (FIO2 and FICO2) stimulates ventilation at rest or during submaximal exercise. We measured minute ventilation (VE) in goats breathing combinations of FIO2 ranging from 0.21 to 0.06 and FICO2 from 0 to 0.05, both with and without inspired CO resulting in carboxyhemoglobin fractions (FHbCO) of 0.02 (no CO added), 0.15, or 0.45. We did this while they stood on a treadmill, walked at 1.4, or trotted at 2.5 m s−1. Hypoxia, hypercapnia, and exercise, alone and in combination, increased ventilation compared to breathing air at rest. Both elevated FHbCO increased VE compared with ambient FHbCO during exercise (increases of 1.50 and 5.53 ml s−1 kg−1 for FHbCO 0.15 and 0.45, respectively; P = 0.035), but not at rest (P = 0.958), when the ventilatory effects of FIO2 and FICO2 are factored out. Additionally, FHbCO 0.45 (but not 0.15) increased VE compared to FHbCO 0.02 for all FIO2 and FICO2 when the ventilatory effects of exercise are factored out. Taken together, these data suggest that exercise intensity and FHbCO dose interact to stimulate ventilation during exercise.
AB - We tested if the addition of CO to inspired gases with different inspired O2 and CO2 fractions (FIO2 and FICO2) stimulates ventilation at rest or during submaximal exercise. We measured minute ventilation (VE) in goats breathing combinations of FIO2 ranging from 0.21 to 0.06 and FICO2 from 0 to 0.05, both with and without inspired CO resulting in carboxyhemoglobin fractions (FHbCO) of 0.02 (no CO added), 0.15, or 0.45. We did this while they stood on a treadmill, walked at 1.4, or trotted at 2.5 m s−1. Hypoxia, hypercapnia, and exercise, alone and in combination, increased ventilation compared to breathing air at rest. Both elevated FHbCO increased VE compared with ambient FHbCO during exercise (increases of 1.50 and 5.53 ml s−1 kg−1 for FHbCO 0.15 and 0.45, respectively; P = 0.035), but not at rest (P = 0.958), when the ventilatory effects of FIO2 and FICO2 are factored out. Additionally, FHbCO 0.45 (but not 0.15) increased VE compared to FHbCO 0.02 for all FIO2 and FICO2 when the ventilatory effects of exercise are factored out. Taken together, these data suggest that exercise intensity and FHbCO dose interact to stimulate ventilation during exercise.
KW - Aerobic capacity
KW - Goat
KW - Hypercapnia
KW - Hypoxia
UR - http://www.scopus.com/inward/record.url?scp=85028411325&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85028411325&partnerID=8YFLogxK
U2 - 10.1016/j.resp.2017.08.012
DO - 10.1016/j.resp.2017.08.012
M3 - Article
C2 - 28843676
AN - SCOPUS:85028411325
VL - 246
SP - 86
EP - 91
JO - Respiratory Physiology and Neurobiology
JF - Respiratory Physiology and Neurobiology
SN - 1569-9048
ER -