Enhanced endothelial activity reflected in cutaneous blood flow oscillations of athletes

Abstract

Functional alterations of vascular endothelial cells may be evaluated by analysing differences in effects of endothelium-dependent [acetylcholine (ACh)] and endothelium-independent [sodium nitroprusside (SNP)] vasodilators. We evaluated whether a dynamic approach using spectral analysis of the blood flow signal, resulting from the cutaneous red cell flux and recorded by the technique of laser Doppler flowmetry (LDF), can detect higher endothelial responsiveness in trained versus less trained individuals. There was a 1.6 times higher ACh-induced cutaneous perfusion in athletes than in controls ( P<0.05), both when evaluated as a mean value of the LDF signal or as the amplitudes of its spectral components. In the frequency interval from 0.009 to 1.6 Hz, ACh induced a 1.6 times higher average spectral amplitude ( P<0.01) in athletes compared with controls. ACh also induced a 1.6 times higher absolute spectral amplitude of the oscillator at around 0.01 Hz ( P<0.05) in the athletes compared with the controls, whereas the endothelial oscillation at around 0.01 Hz during basal unstimulated perfusion was 1.5 times higher ( P<0.01). There were no significant differences in absolute or relative amplitude during iontophoresis with SNP. These results indicate that athletes have higher endothelial activity than less trained individuals.

Assessment of Human Skin Microcirculation and Its Endothelial Function Using Laser Doppler Flowmetry

“…Another interesting approach was by Rossi et al: by performing spectral analysis of the LDF signal, they showed an augmented amplitude of the low frequency band presumably reflecting endothelial function in the trained (Rossi et al, 2006). Similar observations were found in the study performed by Kvernmo et al (Kvernmo et al, 2003).…”

“…It has been postulated that low frequencies around 0.01 Hz might reflect endothelial function, the frequencies at arround 0.04 Hz might reflect the neurogenic influence on the vessel wall, the ones around 0.1 Hz myogenic activity, whereas oscillations of higher frequencies at around 0.3 Hz and 1 Hz reffer to respiratory and heart beat activity, respectively (Kvandal et al, 2006). This is one of the tools used to assess endothelial function in physiologic (Kvernmo et al, 2003) and pathologic (Rossi et al, 2011) conditions. The most widely used spectral methods are fast Fourier transform, autoregressive modeling and wavelet analysis.…”

The 7th European Federation of Autonomic Societies (EFAS) Meeting

“…Results: In group I there were only 4 patients with pathological finding, and the number increased in group II [5] and group III [11]. In spite of expectations, group IV (MSA) did not have the highest percent of patients with OH.…”

“…An overview of recent experiments related to their physiological origin will be presented. The contribution of each of the cardiovascular oscillatory processes can be expected to change with age, after exercise [5] or in diabetes [6], congestive heart failure and acute myocardial infarction. Results of large clinical, multi-center studies will be presented and potentials of the coupled oscillators approach in gaining clinical and physiological insight will be discussed.…”

“…This common behaviour of indices gives a theoretical portrayal of the manoeuvre with 5 major phases: confounded decrease of SP&PSP (1), increase of SP&PSP with first increase of PSP (2), PSP activity above SP, after a peak for PSP (3), SP activity crosses above PSP, following a peak for SP (maximum activity reached throughout the manoeuvre, 3), PSP level of activity becomes constant, yet above a short draw-down and back-up of SP (4) and slight increase of both SP and PSP, with SP above PSP and nearly confounded by two times (5).…”