ArticleThe Journal of physiology2010
Localized tyrosine or tetrahydrobiopterin supplementation corrects the age-related decline in cutaneous vasoconstriction.
Article in The Journal of physiology, 2010. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
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Who cites it
9 citing papers in PubMed, 27 citations in OpenAlex.
- Oral sapropterin augments reflex vasoconstriction in aged human skin through noradrenergic mechanisms.Journal of applied physiology (Bethesda, Md. : 1985) · 2013Trial
- Oral sapropterin acutely augments reflex vasodilation in aged human skin through nitric oxide-dependent mechanisms.Journal of applied physiology (Bethesda, Md. : 1985) · 2013Trial
- Edward F. Adolph Distinguished Lecture: Skin-deep insights into vascular aging.Journal of applied physiology (Bethesda, Md. : 1985) · 2017Review
- Sympathetic control of reflex cutaneous vasoconstriction in human aging.Journal of applied physiology (Bethesda, Md. : 1985) · 2015Review
- Impaired increases in skin sympathetic nerve activity contribute to age-related decrements in reflex cutaneous vasoconstriction.The Journal of physiology · 2015Article
- Tetrahydrobiopterin improves endothelial function in cardiovascular disease: a systematic review.Evidence-based complementary and alternative medicine : eCAM · 2014Review
- Tetrahydrobiopterin does not affect end-organ responsiveness to norepinephrine-mediated vasoconstriction in aged skin.American journal of physiology. Regulatory, integrative and comparative physiology · 2010Article
- Peripheral mechanisms of thermoregulatory control of skin blood flow in aged humans.Journal of applied physiology (Bethesda, Md. : 1985) · 2010Review
- Thermal provocation to evaluate microvascular reactivity in human skin.Journal of applied physiology (Bethesda, Md. : 1985) · 2010Review
Corrections and comments
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Authors and funding
3 authors at 2 institutions in 1 country.
Funding
Abstract
The attenuated reflex vasoconstriction in aged skin may be partly mediated by oxidant-induced reduction in functional substrate and cofactor availability for noradrenaline biosynthesis. We hypothesized that localized supplementation of tyrosine and tetrahydrobiopterin (BH(4)) in aged human skin could augment reflex- (whole-body cooling) and pharmacologically (tyramine, which displaces noradrenaline from axon terminals) induced vasoconstriction. Four microdialysis fibres were placed in the forearm skin of 10 young and 10 older subjects for infusion of (1) Ringer solution (control), (2) 0.5 mm L-tyrosine, (3) 5 mm BH(4), and (4) BH(4) + L-tyrosine. Cutaneous vascular conductance (CVC) was calculated (laser Doppler flux/mean arterial pressure) and normalized to baseline (% Delta CVC(base)). Vasoconstriction was attenuated at the control site in the older subjects during both whole-body cooling (young: 39 +/- 3, older: 17 +/- 3% Delta CVC(base); P < 0.01) and tyramine infusion (young: 41 +/- 3, older: 21 +/- 4% Delta CVC(base); P < 0.01). BH(4) (cold, young: 37 +/- 3, older: 36 +/- 3; tyramine, young: 41 +/- 2, older: 36 +/- 3% Delta CVC(base)) and tyrosine (cold, young: 37 +/- 4, older: 34 +/- 4; tyramine, young: 40 +/- 4, older: 45 +/- 4% Delta CVC(base)) both resolved the age-related decrease in cutaneous vasoconstriction, but BH(4) + tyrosine did not further augment vasoconstriction (cold, young: 38 +/- 4, older: 31 +/- 3; tyramine, young: 36 +/- 3, older: 36 +/- 5 Delta %CVC(base)). These data are consistent with the concept that reduced bioavailability of BH(4) and/or tyrosine may impair noradrenaline synthesis and contribute to the attenuated vasoconstrictor response in aged skin.
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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.