Abstract：
Iontophoresis of vasoactive agents is commonly used to assess cutaneous microvascular reactivity. However, it is known that iontophoresis can be limited by confounding non-specific vasodilatory effects. Despite this, there is still no standardization of protocols or data expression. Therefore, this study evaluated commonly used protocols of iontophoresis by assessing each for evidence of non-specific vasodilatory effects and examined the reproducibility of those protocols that are free of non-specific responses.
Twelve healthy participants were administered doses of acetylcholine (ACh) 1-2% and sodium nitroprusside (SNP) 1%, diluted in sodium chloride 0.9% or deionized water, and insulin 100U/mL in a sterile diluent using iontophoresis coupled with laser speckle contrast imaging (LSCI). Increases in blood flux at a control electrode, containing the diluent only, indicated a non-specific response. Reproducibility of iontophoresis protocols that were free of non-specific vasodilatory effects were subsequently compared to that of post-occlusive reactive hyperemia (PORH), used as a standard, in 20 healthy participants.
Iontophoresis of ACh or SNP in sodium choloride (0.02mA for 200 and 400s, respectively) and ACh in deionized water (0.1mA for 30s) mediated the least non-specific vasodilatory effects. Microvascular responses to insulin were mediated mainly by non-specific effects. Compared to PORH, the intraday and interday reproducibility for iontophoresis of ACh and SNP (0.02mA for 200 and 400s, respectively) with LSCI was weaker, but still deemed good to excellent when data was expressed, in perfusion units or cutaneous vascular conductance, as the absolute peak blood flux response to the vascular reactivity test or as the change in blood flux between peak and baseline values.
This study provides updated recommendations for assessing cutaneous microvascular function with iontophoresis.
Twelve healthy participants were administered doses of acetylcholine (ACh) 1-2% and sodium nitroprusside (SNP) 1%, diluted in sodium chloride 0.9% or deionized water, and insulin 100U/mL in a sterile diluent using iontophoresis coupled with laser speckle contrast imaging (LSCI). Increases in blood flux at a control electrode, containing the diluent only, indicated a non-specific response. Reproducibility of iontophoresis protocols that were free of non-specific vasodilatory effects were subsequently compared to that of post-occlusive reactive hyperemia (PORH), used as a standard, in 20 healthy participants.
Iontophoresis of ACh or SNP in sodium choloride (0.02mA for 200 and 400s, respectively) and ACh in deionized water (0.1mA for 30s) mediated the least non-specific vasodilatory effects. Microvascular responses to insulin were mediated mainly by non-specific effects. Compared to PORH, the intraday and interday reproducibility for iontophoresis of ACh and SNP (0.02mA for 200 and 400s, respectively) with LSCI was weaker, but still deemed good to excellent when data was expressed, in perfusion units or cutaneous vascular conductance, as the absolute peak blood flux response to the vascular reactivity test or as the change in blood flux between peak and baseline values.
This study provides updated recommendations for assessing cutaneous microvascular function with iontophoresis.
摘要：
血管活性剂的离子电渗疗法通常用于评估皮肤微血管反应性。然而,已知离子电渗疗法可以通过混淆非特异性血管舒张作用而受到限制。尽管如此,协议或数据表达仍然没有标准化。因此,本研究通过评估常用的离子电渗疗法方案的非特异性血管舒张作用的证据来评估常用的离子电渗疗法方案,并检查那些没有非特异性反应的方案的可重复性.
12名健康参与者服用乙酰胆碱（ACh）1-2％和硝普钠（SNP）1％的剂量，用0.9%氯化钠或去离子水稀释，和胰岛素100U/mL在无菌稀释剂使用离子电渗结合激光散斑对比成像（LSCI）。控制电极的血液通量增加，只含有稀释剂，表示非特异性反应。随后将没有非特异性血管舒张作用的离子电渗疗法的可重复性与闭塞后反应性充血（PORH）进行比较，用作标准，20名健康参与者。
ACh或SNP在胆酸钠中的离子导入（200和400s时为0.02mA，分别）和去离子水中的ACh（30秒为0.1mA）介导的非特异性血管舒张作用最小。对胰岛素的微血管反应主要由非特异性作用介导。与猪肉相比,ACh和SNP离子电渗疗法的日内和日间重现性(200和400s时为0.02mA，分别)，LSCI较弱，但当数据被表达时，仍然被认为是好到优秀的，在灌注单位或皮肤血管电导中，作为对血管反应性测试的绝对峰值血通量响应或作为峰值和基线值之间的血通量变化。
本研究为离子电渗疗法评估皮肤微血管功能提供了最新建议。
12名健康参与者服用乙酰胆碱（ACh）1-2％和硝普钠（SNP）1％的剂量，用0.9%氯化钠或去离子水稀释，和胰岛素100U/mL在无菌稀释剂使用离子电渗结合激光散斑对比成像（LSCI）。控制电极的血液通量增加，只含有稀释剂，表示非特异性反应。随后将没有非特异性血管舒张作用的离子电渗疗法的可重复性与闭塞后反应性充血（PORH）进行比较，用作标准，20名健康参与者。
ACh或SNP在胆酸钠中的离子导入（200和400s时为0.02mA，分别）和去离子水中的ACh（30秒为0.1mA）介导的非特异性血管舒张作用最小。对胰岛素的微血管反应主要由非特异性作用介导。与猪肉相比,ACh和SNP离子电渗疗法的日内和日间重现性(200和400s时为0.02mA，分别)，LSCI较弱，但当数据被表达时，仍然被认为是好到优秀的，在灌注单位或皮肤血管电导中，作为对血管反应性测试的绝对峰值血通量响应或作为峰值和基线值之间的血通量变化。
本研究为离子电渗疗法评估皮肤微血管功能提供了最新建议。
