The Effects of Chronic Nitrate Supplementation and the Use of Strong and Weak Antibacterial Agents on Plasma Nitrite Concentration and Exercise Blood Pressure.
Chlorhexidine-containing mouthwash (STRONG), which disturbs oral microflora, has been shown to diminish the rise in plasma nitrite concentration ([NO2-]) and attenuate the reduction in resting blood pressure (BP) typically seen after acute nitrate (NO3-) ingestion. We aimed to determine whether STRONG and weaker antiseptic agents attenuate the physiological effects of chronic NO3- supplementation using beetroot juice (BR). 12 healthy volunteers mouth-rinsed with STRONG, non-chlorhexidine mouthwash (WEAK) and deionised water (CON) 3 times a day, and ingested 70 mL BR (6.2 mmol NO3-), twice a day, for 6 days. BP (at rest and during 10 min of treadmill walking) and plasma and salivary [NO3-] and [NO2-] were measured prior to and on day 6 of supplementation. The change in salivary [NO3-] 4 h post final ingestion was higher (P<0.05) in STRONG (8.7±3.0 mM) compared to CON (6.3±0.9 mM) and WEAK (6.0±3.0 mM). In addition, the rise in plasma [NO2-] at 2 h was lower in STRONG compared with WEAK (by 89±112 nM) and CON (by 200±174 nM) and in WEAK compared with CON (all P<0.05). Changes in resting BP were not different between conditions (P>0.05). However, during treadmill walking, the increase in systolic and mean arterial BP was higher 4 h after the final nitrate bolus in STRONG compared with CON (P<0.05) but not WEAK. The results indicate that both strong and weak antibacterial agents suppress the rise in plasma [NO2-] observed following the consumption of a high NO3- diet and the former can influence the BP response during low-intensity exercise.
Sport and Health Sciences, University of Exeter, Exeter, United Kingdom.
S T J
ST
McDonagh
Sport and Health Sciences, University of Exeter, Exeter, United Kingdom.
L J
LJ
Wylie
University of Exeter Medical School, University of Exeter, Exeter, United Kingdom.
P G
PG
Winyard
Sport and Health Sciences, University of Exeter, Exeter, United Kingdom.
A
A
Vanhatalo
Sport and Health Sciences, University of Exeter, Exeter, United Kingdom.
A M
AM
Jones
D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D027461:Beta vulgaris; D001794:Blood Pressure / Q000187:drug effects*; D002710:Chlorhexidine / Q000008:administration & dosage / Q000494:pharmacology*; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology*; D005260:Female; D000067030:Fruit and Vegetable Juices; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D009067:Mouthwashes; D009566:Nitrates / Q000032:analysis / Q000097:blood / Q000494:pharmacology*; D009573:Nitrites / Q000032:analysis / Q000097:blood*; D063177:Pulse Wave Analysis; D012463:Saliva / Q000737:chemistry; D059289:Vascular Stiffness / Q000187:drug effects; D055815:Young Adult
D000900:Anti-Bacterial Agents; D009067:Mouthwashes; D009566:Nitrates; D009573:Nitrites; D002710:Chlorhexidine