Noninvasive Measure of Microvascular Nitric Oxide Function in Humans Using Very Low‐Frequency Cutaneous Laser Doppler Flow Spectra

Abstract

The data suggest that VLF oscillations in the laser Doppler signal are NO dependent, increase with cholinergic stimulation, and have potential as a noninvasive marker for NO-dependent microvascular reactivity.

The contribution of sensory nerves to cutaneous vasodilatation of the forearm and leg to local skin heating

“…While it has been reported that ~90 min is sufficient time to allow for needle insertion trauma to subside in the skin of the forearm following microdialysis fibre placement (Cracowski et al 2011;Anderson et al 1994;Hodges et al 2009), this might not be sufficient for the skin of the leg, resulting in our previously reported higher basal CVC. However, this is unlikely as others have used microdialysis fibres in the legs and reported no such differences in LDF or CVC (Yamazaki and Yuge 2011) or power spectra (Stewart et al 2007). Differences in acclimatization may play a role, as cutaneous blood flow responsiveness is increased with heat acclimation without affecting the maximal (plateau) skin blood flow response (Taylor 2014;Nielsen et al 1993;Rowell et al 1967).…”

To reheat, or to not reheat: that is the question: The efficacy of a local reheating protocol on mechanisms of cutaneous vasodilatation

“…While a strength of this approach is that the protocol does appear to improve the problem of inter-site variability associated with the laser-Doppler (Johnson et al, 1984), it has been suggested that desensitization to local heating may occur at skin sites that have been previously heated (Ciplak et al, 2009;Frantz et al, 2012). The data are equivocal, but it is important to note that these laboratories have examined different skin sites, one using the forearm (Ciplak et al, 2009;Frantz et al, 2012) and the other using the calf (Medow et al, 2008;Stewart et al, 2007b). Additionally, differing rates of skin heating were employed and previous work has clearly demonstrated that the rate of skin heating affects how the cutaneous vasculature responds (Hodges et al, 2009b).…”

“…These mechanisms have been studied at length, with heating protocols remaining relatively homogenous (Hodges and Johnson, 2009;Holowatz, 2008;Holowatz and Kenney, 2010;Johnson and Kellogg, 2010a;Johnson and Kellogg, 2010b;Johnson et al, 2014;Minson, 2010). However, some recently published studies have employed a heat then reheat protocol allowing for each individual skin site to serve as its own control (Medow et al, 2008;Stewart et al, 2007b). While a strength of this approach is that the protocol does appear to improve the problem of inter-site variability associated with the laser-Doppler (Johnson et al, 1984), it has been suggested that desensitization to local heating may occur at skin sites that have been previously heated (Ciplak et al, 2009;Frantz et al, 2012).…”

Role of elasticity of blood vessels in formation of highly amplitude oscillations of a blood flow with frequency of 0.1 Hz

“…В настоящее время принято выделять несколько частотных диапазонов, формирующих колебательную кинетику течения крови. Известно, что формирование колебаний с характерными частотами обусловлено различными ритмическими физиологическими процессами в организме, в частности, сердечными сокращениями [2,3], движениями грудной клетки в процессе дыхания [4,5], миогенной активностью гладкомышечных клеток стенок сосудов [6] [7] и сосудодвигательной активностью эндотелия сосудов [3,[8][9][10].…”