Trial reportThe Journal of physiology2005
Impaired modulation of sympathetic alpha-adrenergic vasoconstriction in contracting forearm muscle of ageing men.
Trial report in The Journal of physiology, 2005. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 74 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
74 citing papers in PubMed, 122 citations in OpenAlex.
- Impaired modulation of postjunctional αThe Journal of physiology · 2018Trial
- No Evidence of Racial Differences in Endothelial Function and Exercise Blood Flow in Young, Healthy Males Following Acute Antioxidant Supplementation.International journal of sports medicine · 2017Trial
- Aging is associated with altered vasodilator kinetics in dynamically contracting muscle: role of nitric oxide.Journal of applied physiology (Bethesda, Md. : 1985) · 2015Trial
- Acute ascorbic acid ingestion increases skeletal muscle blood flow and oxygen consumption via local vasodilation during graded handgrip exercise in older adults.American journal of physiology. Heart and circulatory physiology · 2015Trial
- Acute dietary nitrate supplementation enhances compensatory vasodilation during hypoxic exercise in older adults.Journal of applied physiology (Bethesda, Md. : 1985) · 2015Trial
- Altered neurovascular control of the resting circulation in human metabolic syndrome.The Journal of physiology · 2012Trial
- Oxidative stress and enhanced sympathetic vasoconstriction in contracting muscles of nitrate-tolerant rats and humans.The Journal of physiology · 2012Trial
- Alpha-adrenergic control of blood flow during exercise: effect of sex and menstrual phase.Journal of applied physiology (Bethesda, Md. : 1985) · 2010Trial
- Ageing reduces nitric-oxide- and prostaglandin-mediated vasodilatation in exercising humans.The Journal of physiology · 2007Trial
- Wearable-derived skin temperature dynamics during sleep reveal cardiovascular perfusion deficits through mechanistic modeling.NPJ digital medicine · 2026Article
- Ageing exacerbates the adverse effects of respiratory muscle fatigue on vascular function, locomotor muscle fatigue and exercise performance in males.Experimental physiology · 2026Article
- Role of overweight and obesity on vascular responses to the cold pressor test and hypoxia in women.Journal of applied physiology (Bethesda, Md. : 1985) · 2025Article
- Endogenous muscarinic acetylcholine receptor signaling blunts αAmerican journal of physiology. Regulatory, integrative and comparative physiology · 2025Article
- Vascular dysfunction in COPD with and without chronic respiratory failure: a cross-sectional study.Frontiers in physiology · 2025Article
- Effects of aging on diaphragm hyperemia and blood flow distribution in male and female Fischer 344 rats.American journal of physiology. Regulatory, integrative and comparative physiology · 2024Article
- α-Adrenergic regulation of skeletal muscle blood flow during exercise in patients with heart failure with preserved ejection fraction.The Journal of physiology · 2024Article
- Evidence of impaired functional sympatholysis in patients with heart failure with preserved ejection fraction.American journal of physiology. Heart and circulatory physiology · 2023Article
- Matching of OFrontiers in physiology · 2022Review
- Reduced Endothelial Leptin Signaling Increases Vascular Adrenergic Reactivity in a Mouse Model of Congenital Generalized Lipodystrophy.International journal of molecular sciences · 2021Article
- Sex differences in the vascular response to sympathetic activation during acute hypoxaemia.Experimental physiology · 2021Article
14 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors at 2 institutions in 1 country.
Funding
Abstract
Recent evidence indicates that older healthy humans demonstrate greater vasoconstrictor tone in their active muscles during exercise compared with young adults. Therefore, we tested the hypothesis that the normal ability of muscle contractions to blunt sympathetic alpha-adrenergic vasoconstriction (functional sympatholysis) is impaired with age in healthy humans. We measured forearm blood flow (FBF; Doppler ultrasound) and calculated the forearm vascular conductance (FVC) responses to alpha-adrenergic receptor stimulation during rhythmic handgrip exercise (15% maximum voluntary contraction) and during a control non-exercise vasodilator condition (intra-arterial adenosine infusion) in seven young (25 +/- 2 years) and eight healthy older men (65 +/- 2 year). FVC responses to intra-arterial tyramine (evokes endogenous noradrenaline release), phenylephrine (alpha1-agonist) and clonidine (alpha2-agonist) were assessed. In young men, the vasoconstrictor responses to tyramine (-25 +/- 1 versus -56 +/- 6%), phenylephrine (-11 +/- 4 versus -39 +/- 4%) and clonidine (-12 +/- 4 versus -38 +/- 5%; all P < 0.005) were blunted during exercise compared with adenosine. In contrast, exercise did not significantly blunt the response to tyramine (-30 +/- 2 versus -36 +/- 7%; P = 0.4) or phenylephrine (-16 +/- 2 versus -19 +/- 3%; P = 0.3) in older men, but did attenuate the response to clonidine (-22 +/- 3 versus -37 +/- 6%; P < 0.05). The magnitude of functional sympatholysis, calculated as the difference in the vasoconstrictor responses during adenosine infusion and exercise, was significantly lower in older compared with young men in the presence of tyramine (-6 +/- 7 versus -31 +/- 6%), phenylephrine (-3 +/- 3 versus -28 +/- 4%) and clonidine (-15 +/- 4 versus -26 +/- 3%; all P < 0.05). We conclude that ageing is associated with impaired functional sympatholysis in the vascular beds of contracting forearm muscle in healthy men. These findings might help explain the greater skeletal muscle vasoconstrictor tone and reduced blood flow during large muscle dynamic exercise in older adults.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.