Abstract
Tetrahydrobiopterin‐mediated nitric oxide bioavailability contributes to the variability in vascular endothelial function in healthy middle‐aged/older sedentary adults
The FASEB journal, Vol.22(S2), pp.52-52
04/2008
DOI: 10.1096/fasebj.22.2_supplement.52
Abstract
Aging is associated with impaired endothelial function (endothelium‐dependent dilation, EDD) mediated by decreased nitric oxide (NO) bioavailability. However, there is marked variability in EDD among healthy middle‐aged/older (MA/O) adults. We hypothesized that tetrahydropbiopterin (BH4), a key cofactor for endothelial NO synthase activity, contributes to the variability in NO‐mediated EDD in MA/O adults. MA/O adults (n=25; age 62 ± 1yrs, 16F/9M) with LOW (n=13) and HIGH (n=12) EDD (forearm blood flow, FBF, response to incremental brachial artery infusion of acetylcholine, ACh) differed in plasma C‐reactive protein (Low: 1.8 ± 0.5 vs. High: 0.7 ± 0.1 mg/L) and arterial endothelial NFκB p65 protein expression (Low: 0.75 ± 0.10 vs. High: 0.53 ± 0.07 mg/L, quantitative immunofluorescence) (both P<0.05). In LOW EDD, co‐infusion of BH4 increased the FBF response to ACh by 49% (peak FBF 10.6 ± 1.0 to 15.7 ± 1.5 ml/100 ml/min, P<0.05) compared with ACh alone, but had no effect in HIGH EDD (peak FBF 22.7 ± 1.4 to 23.9 ± 2.7 ml/100 ml/min, P>0.05). Co‐infusion of NO inhibitor NG‐monomethyl‐L‐arginine with BH4 decreased the FBF response to ACh in LOW (peak FBF −44%, P<0.05) and HIGH (peak FBF −53%, P<0.01) EDD such that after NO inhibition EDD was not different between groups (P>0.05). BH4‐mediated NO bioavailability contributes to the variability in vascular endothelial function in healthy MA/O sedentary adults, and increased systemic and vascular inflammation may be intermediary mechanisms involved. Supported by NIH AG013038.
Details
- Title: Subtitle
- Tetrahydrobiopterin‐mediated nitric oxide bioavailability contributes to the variability in vascular endothelial function in healthy middle‐aged/older sedentary adults
- Creators
- Tara N. Fay - University of Colorado BoulderDouglas R. Seals - University of Colorado BoulderIratxe Eskurza - University of Colorado BoulderThomas LaRocca - University of Colorado BoulderAdam J. Bergquist - University of Colorado BoulderGary L. Pierce - University of Colorado Boulder
- Resource Type
- Abstract
- Publication Details
- The FASEB journal, Vol.22(S2), pp.52-52
- Publisher
- Federation of American Societies for Experimental Biology
- DOI
- 10.1096/fasebj.22.2_supplement.52
- ISSN
- 0892-6638
- eISSN
- 1530-6860
- Number of pages
- 1
- Grant note
- NIH (AG013038)
- Language
- English
- Date published
- 04/2008
- Academic Unit
- Health and Human Physiology; Internal Medicine
- Record Identifier
- 9984267257902771
Metrics
6 Record Views