Rossi M, Carpi A, Di Maria C, Franzoni F, Galetta F, Santoro G
Department of Internal Medicine, University of Pisa, Via Roma 67, 56100 Pisa, Italy.
Microvasc Res. 2007 Jul;74(1):9-14. doi: 10.1016/j.mvr.2007.02.006. Epub 2007 Feb 27.
The aim of this study was to clarify whether the post-ischaemic amplification of skin blood flowmotion (SBF) influences the extent of skin post-ischaemic hyperaemia. Forearm skin perfusion was measured by means of laser Doppler flowmetry (LDF) and forearm SBF was examined using Fourier analysis of LDF signal, under basal conditions and following forearm ischaemia in 50 healthy subjects. Power spectral density (PSD) of SBF total spectrum (0.009-1.6 Hz), as well of the frequency intervals (FI) related to endothelial (0.009-0.02 Hz), sympathetic (0.02-0.06 Hz), myogenic (0.06-0.2 Hz), respiratory (0.2-0.6 Hz) and cardiac (0.6-1.6 Hz) activity was measured in PU(2) (LDF perfusion unit)/Hz. Multiple regression analysis evaluated whether post-ischaemic peak-flow, as an indicator of shear stress, or post-ischaemic SBF independently affected the post-peak-flow hyperaemia calculated as corrected area under the LDF curve (C-AUC). Following ischaemia, we observed a statically significant increase in skin perfusion (from basal of 11.7+/-5.8 PU to peak flow of 62.3+/-41.4 PU, p<0.0000005) and in PSD of SBF total spectrum (p<0.01) as well of the different FI considered (p<0.005 for the endothelial and myogenic FI; p<0.05 for the sympathetic, respiratory and cardiac FI) compared to baseline. Multiple regression analysis showed that peak flow and post-ischaemic SBF component of myogenic origin were significant independent variables for the C-AUC (p=0.0000001 and p=0.009, respectively). These findings suggest that not only increased shear stress but also post-ischaemic amplification of myogenic SBF component independently contributes to the more prolonged phase of post-ischaemic skin re-perfusion in healthy subjects.
本研究的目的是阐明缺血后皮肤血流运动（SBF）的增强是否会影响皮肤缺血后充血的程度。在50名健康受试者的基础状态下以及前臂缺血后，通过激光多普勒血流仪（LDF）测量前臂皮肤灌注，并使用LDF信号的傅里叶分析来检测前臂SBF。以PU(2)（LDF灌注单位）/Hz为单位，测量SBF总频谱（0.009 - 1.6 Hz）以及与内皮（0.009 - 0.02 Hz）、交感神经（0.02 - 0.06 Hz）、肌源性（0.06 - 0.2 Hz）、呼吸（0.2 - 0.6 Hz）和心脏（0.6 - 1.6 Hz）活动相关的频率区间（FI）的功率谱密度（PSD）。多元回归分析评估缺血后峰值血流（作为剪切应力的指标）或缺血后SBF是否独立影响以LDF曲线下校正面积（C - AUC）计算的峰值血流后充血。缺血后，我们观察到皮肤灌注（从基础状态的11.7±5.8 PU增加到峰值血流的62.3±41.4 PU，p<0.0000005）以及SBF总频谱的PSD（p<0.01）和所考虑的不同FI（内皮和肌源性FI的p<0.005；交感神经、呼吸和心脏FI的p<0.05）与基线相比有统计学意义的增加。多元回归分析表明，峰值血流和肌源性起源的缺血后SBF成分是C - AUC的显著独立变量（分别为p = 0.0000001和p = 0.009）。这些发现表明，不仅增加的剪切应力，而且肌源性SBF成分的缺血后增强独立地导致了健康受试者缺血后皮肤再灌注的更持久阶段。
