Nitrate pharmacokinetics: Taking note of the difference.
It is now recognised that administration of oral nitrate (NO3(-)), in its various forms, increases the level of nitric oxide (NO) metabolites in the circulation of humans. Its application to modulate physiology and alleviate cardiovascular dysfunction in some patients is now recorded and shows particular promise in hypertension, in modifying platelet activation/aggregation, and in conditions where tissue ischaemia prevails. The potential of oral NO3(-) to modify exercise/performance via elevation of plasma nitrite concentration ([NO2(-)]) has been applied across a range of human test systems. Herein we discuss how the choice of NO3(-) source, route of administration and resulting pharmacokinetics might influence the outcome of physiological measures and potentially contribute to discrepancies in performance trials. There are but a few examples of detailed pharmacokinetic data on which the majority of researchers base their test protocols in different cohorts/settings. We compare and contrast the results of key publications with the aim of highlighting a consensus of our current understanding and critical considerations for those entering the field.
Wales Heart Research Institute, Cardiff University Medical School, Heath Park, Cardiff CF14 4XN, United Kingdom. Electronic address: jamespp@cardiff.ac.uk.
Philip E
PE
James
Wales Heart Research Institute, Cardiff University Medical School, Heath Park, Cardiff CF14 4XN, United Kingdom.
Gareth R
GR
Willis
Clinical Exercise Science Research Program, Institute of Sport, Exercise and Active Living (ISEAL), Victoria University, Melbourne, Australia.
Jason D
JD
Allen
University of Exeter Medical School, St. Luke's Campus, Heavitree Road, Exeter EX1 2LU, United Kingdom.
Paul G
PG
Winyard
Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, St Luke's Campus, Heavitree Road, Exeter EX1 2LU, United Kingdom.
Andrew M
AM
Jones
D000284:Administration, Oral; D015444:Exercise / Q000502:physiology*; D006801:Humans; D009566:Nitrates / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D010809:Physical Fitness; D012107:Research Design; D014675:Vegetables / Q000737:chemistry*
D009566:Nitrates
Exercise; Nitrate; Nitrite; Pharmacokinetics