Passive leg movement-induced vasodilation and exercise-induced sympathetic vasoconstriction

The role of nitric oxide (NO) as a modulator of functional sympatholysis has been debated in the literature, but the preponderance of evidence suggests that the magnitude of NO-mediated dilation is restrained by sympathetic vasoconstriction. Therefore, we hypothesized that passive leg movement (PLM)-induced vasodilation, which is predominantly NO-mediated, would be attenuated by an exercise-induced increase in muscle sympathetic nerve activity (MSNA). To test this hypothesis, MSNA, leg blood flow (LBF), and mean arterial blood pressure (MAP) were measured and leg vascular conductance (LVC) calculated in 9 healthy subjects (30  ± 3 yr), during PLM with and without sympathoexcitation evoked by arm-cranking exercise (ACE), at 25, 50, and 75% of maximal capacity.

Source: Autonomic Neuroscience: Basic and Clinical - March 4, 2022 Category: Neuroscience Authors: Massimo Venturelli, Matthew J. Rossman, Stephen J. Ives, Joshua C. Weavil, Markus Amann, D. Walter Wray, Russell S. Richardson Source Type: research