Persistence of functional sympatholysis post-exercise in human skeletal muscle
Open Access
- 1 January 2013
- journal article
- research article
- Published by Frontiers Media SA in Frontiers in Physiology
- Vol. 4, 131
- https://doi.org/10.3389/fphys.2013.00131
Abstract
Blunting of sympathetic vasoconstriction in exercising muscle is well-established. Whether it persists during the early post-exercise period is unknown. This study tested the hypothesis that it persists in human skeletal muscle during the first 10 min of recovery from exercise. Eight healthy young males (21.4 ± 0.8 yrs, SE) performed 7 min of forearm rhythmic isometric handgrip exercise at 15% below forearm critical force (fCF). In separate trials, a cold pressor test (CPT) of 2 min duration was used to evoke forearm sympathetic vasoconstriction in each of Rest (R), Steady State Exercise (Ex), 2–4 min Post-Exercise (PEearly), and 8–10 min Post-Exercise (PElate). A 7 min control exercise trial with no CPT was also performed. Exercising forearm brachial artery blood flow, arterial blood pressure, cardiac output (CO), heart rate (HR), forearm deep venous catecholamine concentration, and arterialized venous catecholamine concentration were obtained immediately prior to and following the CPT in each trial. CPT resulted in a significant increase in forearm venous plasma norepinephrine concentration in all trials (P = 0.007), but no change in arterialized plasma norepinephrine (P = 0.32). CPT did not change forearm venous plasma epinephrine (P = 0.596) or arterialized plasma epinephrine concentration (P = 0.15). As assessed by the %reduction in forearm vascular conductance (FVC) the CPT evoked a robust vasoconstriction at rest that was severely blunted in exercise (R = −39.9 ± 4.6% vs. Ex = 5.5 ± 7.4%, P < 0.001). This blunting of vasoconstriction persisted at PEearly (-12.3 ± 10.1%, P = 0.02) and PElate (-18.1 ± 8.2%, P = 0.03) post-exercise. In conclusion, functional sympatholysis remains evident in human skeletal muscle as much as 10 min after the end of a bout of forearm exercise. Persistence of functional sympatholysis may have important implications for blood pressure regulation in the face of a challenge to blood pressure following exercise.Keywords
This publication has 50 references indexed in Scilit:
- Inefficient functional sympatholysis is an overlooked cause of malperfusion in contracting skeletal muscleJournal Of Physiology-London, 2012
- Oxidative stress and enhanced sympathetic vasoconstriction in contracting muscles of nitrate‐tolerant rats and humansJournal Of Physiology-London, 2012
- Graded sympatholytic effect of exogenous ATP on postjunctional α‐adrenergic vasoconstriction in the human forearm: implications for vascular control in contracting muscleJournal Of Physiology-London, 2008
- Muscle metabolic responses to exercise above and below the “critical power” assessed using31P-MRSAmerican Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 2008
- Intravascular ADP and soluble nucleotidases contribute to acute prothrombotic state during vigorous exercise in humansJournal Of Physiology-London, 2007
- α‐Adrenergic Vascular Responsiveness during Postexercise Hypotension in HumansJournal Of Physiology-London, 2003
- Erythrocyte and the Regulation of Human Skeletal Muscle Blood Flow and Oxygen DeliveryCirculation Research, 2002
- NEURAL CONTROL OF MUSCLE BLOOD FLOW: IMPORTANCE DURING DYNAMIC EXERCISEClinical and Experimental Pharmacology and Physiology, 1997
- Metabolic and respiratory profile of the upper limit for prolonged exercise in manErgonomics, 1988
- Effect of cold pressor stimulation on plasma norepinephrine, dopamine-β-hydroxylase, and renin activityLife Sciences, 1977