TY - JOUR
T1 - Blood temperature and perfusion to exercising and non-exercising human limbs
AU - González-Alonso, José
AU - Calbet, José A. L.
AU - Boushel, Robert
AU - Helge, Jørn W.
AU - Søndergaard, Hans
AU - Munch-Andersen, Thor
AU - van Hall, Gerrit
AU - Mortensen, Stefan P.
AU - Secher, Niels H.
N1 - © 2015 The Authors Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.
PY - 2015/10/1
Y1 - 2015/10/1
N2 - New Findings: What is the central question of this study? Temperature-sensitive mechanisms are thought to contribute to blood-flow regulation, but the relationship between exercising and non-exercising limb perfusion and blood temperature is not established. What is the main finding and its importance? The close coupling among perfusion, blood temperature and aerobic metabolism in exercising and non-exercising extremities across different exercise modalities and activity levels and the tight association between limb vasodilatation and increases in plasma ATP suggest that both temperature- and metabolism-sensitive mechanisms are important for the control of human limb perfusion, possibly by activating ATP release from the erythrocytes. Temperature-sensitive mechanisms may contribute to blood-flow regulation, but the influence of temperature on perfusion to exercising and non-exercising human limbs is not established. Blood temperature (TB), blood flow and oxygen uptake (V˙O2) in the legs and arms were measured in 16 healthy humans during 90 min of leg and arm exercise and during exhaustive incremental leg or arm exercise. During prolonged exercise, leg blood flow (LBF) was fourfold higher than arm blood flow (ABF) in association with higher TB and limb V˙O2. Leg and arm vascular conductance during exercise compared with rest was related closely to TB (r2 = 0.91; P < 0.05), plasma ATP (r2 = 0.94; P < 0.05) and limb V˙O2 (r2 = 0.99; P < 0.05). During incremental leg exercise, LBF increased in association with elevations in TB and limb V˙O2, whereas ABF, arm TB and V˙O2 remained largely unchanged. During incremental arm exercise, both ABF and LBF increased in relationship to similar increases in V˙O2. In 12 trained males, increases in femoral TB and LBF during incremental leg exercise were mirrored by similar pulmonary artery TB and cardiac output dynamics, suggesting that processes in active limbs dominate central temperature and perfusion responses. The present data reveal a close coupling among perfusion, TB and aerobic metabolism in exercising and non-exercising extremities and a tight association between limb vasodilatation and increases in plasma ATP. These findings suggest that temperature and V˙O2 contribute to the regulation of limb perfusion through control of intravascular ATP.
AB - New Findings: What is the central question of this study? Temperature-sensitive mechanisms are thought to contribute to blood-flow regulation, but the relationship between exercising and non-exercising limb perfusion and blood temperature is not established. What is the main finding and its importance? The close coupling among perfusion, blood temperature and aerobic metabolism in exercising and non-exercising extremities across different exercise modalities and activity levels and the tight association between limb vasodilatation and increases in plasma ATP suggest that both temperature- and metabolism-sensitive mechanisms are important for the control of human limb perfusion, possibly by activating ATP release from the erythrocytes. Temperature-sensitive mechanisms may contribute to blood-flow regulation, but the influence of temperature on perfusion to exercising and non-exercising human limbs is not established. Blood temperature (TB), blood flow and oxygen uptake (V˙O2) in the legs and arms were measured in 16 healthy humans during 90 min of leg and arm exercise and during exhaustive incremental leg or arm exercise. During prolonged exercise, leg blood flow (LBF) was fourfold higher than arm blood flow (ABF) in association with higher TB and limb V˙O2. Leg and arm vascular conductance during exercise compared with rest was related closely to TB (r2 = 0.91; P < 0.05), plasma ATP (r2 = 0.94; P < 0.05) and limb V˙O2 (r2 = 0.99; P < 0.05). During incremental leg exercise, LBF increased in association with elevations in TB and limb V˙O2, whereas ABF, arm TB and V˙O2 remained largely unchanged. During incremental arm exercise, both ABF and LBF increased in relationship to similar increases in V˙O2. In 12 trained males, increases in femoral TB and LBF during incremental leg exercise were mirrored by similar pulmonary artery TB and cardiac output dynamics, suggesting that processes in active limbs dominate central temperature and perfusion responses. The present data reveal a close coupling among perfusion, TB and aerobic metabolism in exercising and non-exercising extremities and a tight association between limb vasodilatation and increases in plasma ATP. These findings suggest that temperature and V˙O2 contribute to the regulation of limb perfusion through control of intravascular ATP.
U2 - 10.1113/EP085383
DO - 10.1113/EP085383
M3 - Journal article
C2 - 26268717
SN - 0958-0670
VL - 100
SP - 1118
EP - 1131
JO - Experimental Physiology
JF - Experimental Physiology
IS - 10
ER -
