TY - JOUR
T1 - Blood viscosity and hemodynamics during exercise
AU - Connes, Philippe
AU - Pichon, Aurélien
AU - Hardy-Dessources, Marie Dominique
AU - Waltz, Xavier
AU - Lamarre, Yann
AU - Simmonds, Michael J.
AU - Tripette, Julien
PY - 2012
Y1 - 2012
N2 - We tested the effects of submaximal exercise on blood viscosity (η b), nitric oxide production (NO) and hemodynamics. Relationships between the exercise-induced changes that occurred in these parameters were investigated. Nine subjects performed exercise for 15 min at 105% of the first ventilatory threshold. Mean arterial pressure (MAP) and cardiac output (Qc) were measured, allowing the determination of systemic vascular resistance (SVR). Blood was sampled at rest and at the end of exercise. The η b was determined at high shear rate and was used to calculate systemic vascular hindrance (VH). NO production was estimated by measuring plasma concentrations of NO stable end products (NOx). Qc, MAP, η b and NOx, increased with exercise, whereas SVR and VH decreased. The changes between rest and exercise were calculated and tested for correlations. We observed: 1) a positive correlation between the increase in η b and the increase in NOx; 2) a negative correlation between the increase in NOx and the decrease in VH; 3) a negative correlation between the increase in η b and the decrease in SVR. Although the increase in Qc and blood flow during exercise probably promoted NO production due to shear dependent stimulation of the endothelium, the present results also support that the rise in η b during exercise may be necessary for NO production and adequate vasodilation.
AB - We tested the effects of submaximal exercise on blood viscosity (η b), nitric oxide production (NO) and hemodynamics. Relationships between the exercise-induced changes that occurred in these parameters were investigated. Nine subjects performed exercise for 15 min at 105% of the first ventilatory threshold. Mean arterial pressure (MAP) and cardiac output (Qc) were measured, allowing the determination of systemic vascular resistance (SVR). Blood was sampled at rest and at the end of exercise. The η b was determined at high shear rate and was used to calculate systemic vascular hindrance (VH). NO production was estimated by measuring plasma concentrations of NO stable end products (NOx). Qc, MAP, η b and NOx, increased with exercise, whereas SVR and VH decreased. The changes between rest and exercise were calculated and tested for correlations. We observed: 1) a positive correlation between the increase in η b and the increase in NOx; 2) a negative correlation between the increase in NOx and the decrease in VH; 3) a negative correlation between the increase in η b and the decrease in SVR. Although the increase in Qc and blood flow during exercise probably promoted NO production due to shear dependent stimulation of the endothelium, the present results also support that the rise in η b during exercise may be necessary for NO production and adequate vasodilation.
KW - Exercise
KW - hemorheology
KW - nitric oxide
KW - vascular resistance
KW - vasodilation
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UR - http://www.scopus.com/inward/citedby.url?scp=84861976316&partnerID=8YFLogxK
U2 - 10.3233/CH-2011-1515
DO - 10.3233/CH-2011-1515
M3 - Article
C2 - 22240371
AN - SCOPUS:84861976316
SN - 1386-0291
VL - 51
SP - 101
EP - 109
JO - Clinical hemorheology and microcirculation
JF - Clinical hemorheology and microcirculation
IS - 2
ER -