ME/CVS-patiënten produceren aanzienlijk meer nitraten tijdens een inspanningsproef.
Nitraten zijn stoffen die tijdens de stofwisseling wordt gevormd uit stikstofoxide.
Teneinde de zuurstoftoevoer te maximaliseren tijdens een inspanning maakt het
lichaam meer stikstofoxide aan,
waardoor de bloedvaten verwijden (vasodilatatie).
Daarom neemt de concentratie stikstofoxide bij een fysieke of mentale inspanning toe.
Bij ME/CVS-patiënten is die toename echter veel groter,
mogelijk in een uiterste poging om de bloedtoevoer (zuurstofaanvoer!) op gang te houden.
Een nadelig gevolg van dit verschijnsel:
de hoeveelheid antioxidanten (glutathione, vitamine C etc.) zal eerder uitgeput raken.
Nitric oxide metabolite production during exercise in chronic fatigue syndrome:
a case-control study.
J Womens Health (Larchmt). 2010 May 14. doi:10.1089/jwh.2008.1255.
Suárez A, Guillamo E, Roig T, Blázquez A, Alegre J, Bermúdez J, Ventura JL, García-Quintana AM, Comella A, Segura R, Javierre C.
Abstract
Background:
Chronic fatigue syndrome (CFS)
is a disabling illness of unknown etiology
that is characterized by fatigue
associated with a reduced ability to work,
lasting for more than 6 months, and
accompanied by a specific set of symptoms.
The diagnosis remains difficult
because of the absence of laboratory tests and
is, therefore, made largely on the basis of the symptoms reported by the patient.
The aim of this study was to analyze differences
in blood nitrate levels in CFS patients and a matched control group
after a physical exercise test.
Methods:
Forty-four consecutive female patients with CFS and 25 healthy women
performed an exercise test
using a cycle ergometer with monitoring of cardiopulmonary response.
Blood samples were obtained
for biochemical analyses of glucose, lactate, and nitrates
at the beginning (under resting conditions) and after the maximal and supramaximal tests.
Results:
Plasma nitrates differed between the groups,
with higher values in the CFS group (F = 6.93, p = 0.003).
Nitrate concentration increased in relation to workload and
reached higher values in the CFS group,
the maximum difference with respect to the control group being 295% (t = 4.88, p < 0.001).
Conclusions:
The main result of the present study is that
nitric oxide (NO) metabolites (nitrates)
showed a much higher increase
after a maximal physical test
in CFS patients than in a group of matched subjects.
This combination (exercise plus NO response evaluation)
may be useful in the assessment of CFS.
PMID: 20469961 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/20469961
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