Okuno T, Sugiyama T, Kohyama M, Kojima S, Oku H, Ikeda T
Department of Ophthalmology, Osaka Medical College, Takatsuki, Osaka, Japan.
Eye (Lond). 2006 Jul;20(7):796-800. doi: 10.1038/sj.eye.6702004. Epub 2005 Jul 8.
To investigate control mechanisms for ocular blood flow changes after dynamic exercise using two different methods.
Changes over time in the tissue blood flow in the retina and choroid-retina of healthy volunteers were determined after dynamic exercise (Master's double two-step test), using scanning laser Doppler flowmetry (SLDF) and laser speckle flowgraphy (LSFG). Changes in intraocular pressure (IOP), blood pressure, plasma CO(2) gas concentration (pCO(2)), and levels of nitric oxide (NO) metabolites were examined.
Retinal blood flow measured by SLDF increased significantly only at 15 min after exercise. In contrast, normalized blur (NB) values in the choroid-retina, obtained by LSFG, increased significantly up to 60 min after exercise. Ocular perfusion pressure (OPP), calculated from IOP and blood pressure, increased significantly immediately and 15 min after exercise. The plasma NO metabolite levels increased significantly, although pCO(2) levels were unchanged.
Dynamic exercise changes OPP and produces increased tissue blood flow in the retina in the immediate postexercise period, while blood flow increases more persistently in the choroid-retina. Difference in control of blood flow in these two regions may be related to stronger autoregulatory mechanism of blood flow in the retina. Nitric oxide may play a role in the regulation of blood flow.
使用两种不同方法研究动态运动后眼血流变化的控制机制。
在健康志愿者进行动态运动（Master氏双二步试验）后，采用扫描激光多普勒血流仪（SLDF）和激光散斑血流图仪（LSFG）测定视网膜及脉络膜 - 视网膜组织血流随时间的变化。检测眼内压（IOP）、血压、血浆二氧化碳气体浓度（pCO₂）及一氧化氮（NO）代谢产物水平的变化。
通过SLDF测量的视网膜血流仅在运动后15分钟显著增加。相比之下，通过LSFG获得的脉络膜 - 视网膜归一化模糊（NB）值在运动后60分钟内显著增加。由IOP和血压计算得出的眼灌注压（OPP）在运动后即刻和15分钟显著升高。血浆NO代谢产物水平显著升高，尽管pCO₂水平未变。
动态运动可改变OPP，并在运动后即刻使视网膜组织血流增加，而脉络膜 - 视网膜血流增加更为持久。这两个区域血流控制的差异可能与视网膜更强的血流自身调节机制有关。一氧化氮可能在血流调节中起作用。
