Kiryu J, Asrani S, Shahidi M, Mori M, Zeimer R
Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, USA.
Invest Ophthalmol Vis Sci. 1995 Jun;36(7):1240-6.
To study the response of the macular circulation to a local increase in metabolic demand created by a flickering source of illumination.
Laser-targeted angiography (release of a fluorescent dye from heat-sensitive liposomes using a laser pulse) was used to study, in subhuman primates, changes in hemodynamic parameters of the retinal circulation that were induced by a flickering source of illumination. Changes in the macular macrocirculation were compared with those in the macular microcirculation and were evaluated at various distances from the foveola.
In response to monochromatic light flicker, the blood flow in retinal arteries increased by 30%. The response of the microcirculation was not homogeneous. It showed a maximum increase in the mid-perifoveal region where there is an increase in ganglion cells and nerve fibers. Interestingly, the maximum change in the index representing capillary blood flow exceeded the blood flow change in the artery (P < 0.08).
A stimulus expected to cause increased metabolic demand results in a regulatory response by the retinal microcirculation. This response shows spatial variations that correspond with known variations in retinal anatomy. The authors propose that a redistribution of blood can occur between the capillary layers to fulfill high metabolic demands by neuronal tissue remote from the choroid.
研究黄斑循环对闪烁光源所产生的局部代谢需求增加的反应。
在非人灵长类动物中，使用激光靶向血管造影术（利用激光脉冲从热敏脂质体中释放荧光染料）来研究闪烁光源引起的视网膜循环血流动力学参数变化。将黄斑大循环的变化与黄斑微循环的变化进行比较，并在距中央凹不同距离处进行评估。
对单色光闪烁的反应中，视网膜动脉血流增加了30%。微循环的反应并不均匀。在神经节细胞和神经纤维增加的中央凹周围中部区域，血流增加最为明显。有趣的是，代表毛细血管血流的指标的最大变化超过了动脉血流变化（P < 0.08）。
预期会导致代谢需求增加的刺激会引发视网膜微循环的调节反应。这种反应表现出与视网膜解剖结构已知变化相对应的空间差异。作者提出，血液可在毛细血管层之间重新分布，以满足远离脉络膜的神经元组织的高代谢需求。
