Impact of shear rate pattern on post-occlusive near-infrared spectroscopy microvascular reactivity

Publication date: March 2018 Source:Microvascular Research, Volume 116 Author(s): M. Ramos Gonzalez, J.T. Caldwell, P.A. Branch, G.C. Wardlow, C.D. Black, J. Campbell, R.D. Larson, C.J. Ade The primary aim of the present study was to determine the impact of acute changes in shear rate patterns, in particular retrograde shear rate, on microvascular function in 15 healthy, young men and women as determined via the post-occlusive near-infrared spectroscopy (NIRS) microvascular reactivity response. Microvascular reactivity, via NIRS-derived measurements of post-occlusion tissue saturation index (TSI%) and total microvascular hemoglobin+myoglobin concentration ([Hb]total), were assessed in each participant before and immediately after exposure to a 30min retrograde shear treatment. Retrograde shear was achieved via a blood pressure cuff placed below the knee inflated to 75mmHg. One leg was exposed to the retrograde shear (Treatment leg) and the contralateral leg served as a non-treatment control. In the Treatment leg, significant increases in retrograde shear rate occurred during the retrograde intervention. Following the intervention, the area under the TSI% post-occlusion response curve, which represents the total microvascular reactivity response, and the absolute peak TSI% response were significantly increased compared to pre-intervention in the Treatment leg, but not the Control leg. The absolute peak [Hb]total response was significantly increased post-intervention ...

Source: Microvascular Research - November 6, 2017 Category: Biochemistry Source Type: research