Plasma and platelet catecholamine and catecholamine sulfate response to various exercise tests
Strobel, G.; Friedmann, B.; Jost, J.; Bärtsch, P.
American Journal of Physiology 267(4 Pt 1): E537-E543
1994
ISSN/ISBN: 0002-9513 PMID: 7943302 Document Number: 424954
We tested the hypothesis that platelet and plasma catecholamine sulfates (CA-S) and platelet catecholamines (CA) reflect the overall sympathoadrenergic activation by exercise of 1 h duration. Ten well-trained subjects performed a low-intensity (62% maximum 02 consumption ( ovrhdot VO-2max); LI) and a high-intensity exercise test (77% ovrhdot VO-2max; HI) and two tests at a similar average power output that consisted of 20 min at 77% ovrhdot VO-2max and 40 min at 62% ovrhdot VO-2max (HI/LI) and vice versa (LI/HI). Plasma norepinephrine sulfate (NE-S) increased to higher levels after HI than after LI exercise (15.5 +- 2.1 vs. 8.9 +- 0.7 nmol/1). Immediately after HI/LI and LI/HI plasma NE-S was similarly increased (9.59 +- 1.1 vs. 9.96 +- 1.3 nmol/1), whereas norepinephrine was higher after LI/HI than after HI/LI (23.0 +- 3.2 vs. 15.7 +- 2.3 nmol/l). Platelet CA and CA-S were increased only after HI. In conclusion, the plasma NE-S response to exercise parallels the overall sympathetic activation. These results support the hypothesis that plasma NE-S measured immediately after exercise reflects the overall sympathoadrenergic activity over prolonged periods of exercise. Platelet CA and CA-S poorly reflect sympathoadrenergic activation.