Chuman Hideki, Sugimoto Takako, Nao-I Nobuhisa
Department of Ophthalmology, Faculty of Medicine, University of Miyazaki, 5200 Kihara Kiyotake, Miyazaki City, Miyazaki Prefecture, 889-1692, Japan.
Graefes Arch Clin Exp Ophthalmol. 2017 Dec;255(12):2381-2388. doi: 10.1007/s00417-017-3824-5. Epub 2017 Oct 23.
This study aimed to clarify the vasodilatory effect of L-arginine on isolated rabbit and human posterior ciliary arteries (PCAs) and to investigate changes in optic disc blood flow after an infusion of L-arginine in vivo.
Vascular ring segments were mounted on a double myograph system. After obtaining maximal contraction following administration of high-K solution, L-arginine was administrated. Six volunteers received an intravenous drip infusion of 100 ml of L-arginine or saline. Changes in optic disc blood flow were measured by laser speckle flowgraphy.
L-arginine relaxed high-K solution-induced contracted rabbit PCAs. Carboxy-PTIO (nitric oxide scavenger) and L-NAME (nitric oxide synthase inhibitor) inhibited L-arginine-induced relaxation in rabbit PCAs. After removal of the endothelium of the rabbit PCAs, L-arginine still relaxed rabbit PCAs. L-arginine relaxed human PCAs, despite the lack of nitric oxide production. In the L-arginine infusion group, the mean blur rate was significantly greater than that of the control group in vivo.
L-arginine has both nitric oxide-dependent and independent vasodilatory effect on high K- induced contractions in isolated rabbit and human PCAs. L-arginine increased optic disc blood flow in vivo.
本研究旨在阐明L-精氨酸对离体兔和人睫状后动脉（PCA）的血管舒张作用，并研究体内输注L-精氨酸后视盘血流的变化。
将血管环段安装在双肌动描记系统上。在给予高钾溶液后获得最大收缩后，给予L-精氨酸。六名志愿者接受了100毫升L-精氨酸或生理盐水的静脉滴注。通过激光散斑血流图测量视盘血流的变化。
L-精氨酸使高钾溶液诱导收缩的兔PCA舒张。羧基-PTIO（一氧化氮清除剂）和L-NAME（一氧化氮合酶抑制剂）抑制L-精氨酸诱导的兔PCA舒张。去除兔PCA的内皮后，L-精氨酸仍使兔PCA舒张。尽管不产生一氧化氮，L-精氨酸仍使人类PCA舒张。在L-精氨酸输注组中，体内平均模糊率显著高于对照组。
L-精氨酸对离体兔和人PCA中高钾诱导的收缩具有一氧化氮依赖性和非依赖性血管舒张作用。L-精氨酸可增加体内视盘血流。
