Premium
Heterogenous vasodilator pathways underlie flow‐mediated dilation in men and women
Author(s) -
Parker Beth A.,
Tschakovsky Michael E.,
Augeri Amanda L.,
Polk Donna M.,
Thompson Paul D.,
Kiernan Francis J.
Publication year - 2011
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.25.1_supplement.818.4
Purpose To investigate sex differences in the contribution of nitric oxide (NO) and prostaglandins (PG) to flow‐mediated dilation (FMD). Methods Radial artery (RA) FMD, assessed as the dilatory response to 5 minutes distal cuff occlusion, was repeated after three separate brachial artery infusions of saline (SAL), N(G)‐monomethyl‐L‐arginine (L‐NMMA), and L‐NMMA + ketorolac (KETO) in healthy younger men (M; n=7) and women (W; n=8). RA FMD was calculated as the peak dilatory response observed relative to baseline (%D) and normalized to the corresponding area under the curve shear rate (AUCSR). Results L‐NMMA reduced %D similarly (p=0.94 for sex*time interaction) in M and W (M:8.1±3.3 to 5.7±3.2% and W:12.1±3.5 to 9.5±5.4%; p<0.05); the effect was no longer significant when %D was normalized to AUCSR (p=0.11). There were no time or sex effects of KETO on %D or %D/AUCSR (all p>0.32). Moreover, KETO administration evoked large inter‐individual differences as 7 subjects (3M,4W) exhibited −6 to −77% reductions in %D/AUCSR and 8 subjects (4M,4W) exhibited 15 to 106% increases in %D/AUCSR. Conclusions These findings suggest that NO is not obligatory for RA FMD in either men or women, and multiple pathways influence the conduit dilatory response to ischemia.