Journal article
The catecholamines strike back. What NO does not do
Circulation journal : official journal of the Japanese Circulation Society, Vol.73(10), pp.1783-1792
10/2009
DOI: 10.1253/circj.CJ-09-0559
PMCID: PMC3760385
PMID: 19729859
Abstract
The discovery of endothelial-derived relaxing factor, and later nitric oxide (NO), as a biologically active substance led to intense focus on the vascular endothelium as a major site of physiological regulation and pathophysiological dysfunction. NO is clearly a potent vasodilator and plays a key role in establishing both whole body and regional "vascular tone". In this context, skeletal muscle and human skin have the remarkable capacity to increase their blood flow 50-100-fold and this increase is caused almost exclusively by local vasodilation. In general, the mechanisms responsible for these vasodilator phenomena have been poorly understood. In the early 1990s, investigators started to ask if NO might explain the "unexplained" vasodilator responses seen in skeletal muscle and skin. They also asked how "NO tone" interacted with "sympathetic tone" and whether NO can override the vasoconstrictor responses normally generated when sympathetic nerves release norepinephrine. Surprisingly, it was found that NO plays only a modest (non-obligatory) role in exercise hyperemia, reactive hyperemia and the neurally mediated rise in skin blood flow during whole body heat stress. By contrast, NO plays a major role in the skeletal muscle vasodilator responses to mental stress and the skin dilator responses to local heating. In animals, but not humans, NO can limit the ability of the sympathetic nerves to cause vasoconstriction in exercising muscles. Thus the role of NO in two of the most extreme dilator responses seen in nature is limited and in muscle the sympathetic nerves can restrain the dilation to defend arterial blood pressure.
Details
- Title: Subtitle
- The catecholamines strike back. What NO does not do
- Creators
- Michael J Joyner - Department of Anesthesiology, Mayo Clinic,Rochester, MN 55905, USA. joyner.michael@mayo.eduDarren P Casey
- Resource Type
- Journal article
- Publication Details
- Circulation journal : official journal of the Japanese Circulation Society, Vol.73(10), pp.1783-1792
- Publisher
- Japan
- DOI
- 10.1253/circj.CJ-09-0559
- PMID
- 19729859
- PMCID
- PMC3760385
- ISSN
- 1346-9843
- eISSN
- 1347-4820
- Grant note
- P50 NS032352 / NINDS NIH HHS AR55819 / NIAMS NIH HHS N01NS32352 / NINDS NIH HHS F32 AR055819 / NIAMS NIH HHS HL46493 / NHLBI NIH HHS R01 HL046493 / NHLBI NIH HHS HL83947 / NHLBI NIH HHS R01 HL083947 / NHLBI NIH HHS
- Language
- English
- Date published
- 10/2009
- Academic Unit
- Physical Therapy and Rehabilitation Science; Fraternal Order of Eagles Diabetes Research Center
- Record Identifier
- 9984047714002771
Metrics
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