Mechanism of cutaneous vasodilation following acupuncture stimulation-Investigation using microdialysis-

本研究旨在通过观察一氧化氮（NO）和轴突反射性血管舒张反应在针刺刺激皮肤血管舒张中的作用，阐明针刺刺激皮肤血管舒张的机制。通过比较利多卡因乳膏治疗部位和未治疗部位，研究感觉神经元轴突反射血管舒张的作用。尽管利多卡因乳膏治疗部位的机械刺激感觉阈值增加，但皮肤血管传导性（CVC）和面积随时间的变化在治疗部位和未治疗部位之间无显著差异。然后，我们研究了NO的作用，通过皮内给药N^G-硝基-L-精氨酸甲酯盐酸盐（L-NAME 20 mM），一种NO合成酶抑制剂，使用皮内微透析。与对照组（给予林格氏溶液）相比，给予L-NAME的部位在针刺刺激后随时间推移显示CVC显著降低。这些结果表明，机制以外的轴突反射血管扩张的感觉神经元参与皮肤血管扩张针刺刺激后，和NO是部分参与。

We aimed to elucidate the mechanism of cutaneous vasodilation following acupuncture stimulation by investigating the roles of nitrogen monoxide (NO) and axon reflex vasodilation. The role of axon reflex vasodilation by sensory neurons was investigated by comparing sites treated with lidocaine cream with untreated sites. Although the sensory threshold for mechanical stimulation increased in sites treated with lidocaine cream, changes over time in cutaneous vascular conductance (CVC) and area did not significantly differ between treated and untreated sites. We then investigated the role of NO by intradermally administering N^G-nitro-L-arginine methyl ester hydrochloride (L-NAME 20 mM), an NO synthase inhibitor, using intradermal microdialysis. Compared to controls (administered Ringer's solution), sites administered L-NAME showed a significant reduction in CVC over time following acupuncture stimulation. These findings suggest that mechanisms other than axon reflex vasodilation by sensory neurons are involved in cutaneous vasodilation following acupuncture stimulation, and that NO is partially involved.