Told Reinhard, Palkovits Stefan, Boltz Agnes, Schmidl Doreen, Napora Katarzyna J, Werkmeister René M, Haslacher Helmuth, Frantal Sophie, Popa-Cherecheanu Alina, Schmetterer Leopold, Garhöfer Gerhard
Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria; Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
Acta Ophthalmol. 2014 Nov;92(7):e540-5. doi: 10.1111/aos.12433. Epub 2014 May 26.
The complement factor H (CFH) tyrosine 402 histidine (Y402H, rs1061170) variant is known to be significantly associated with age-related macular degeneration (AMD). Whether this genetic variant may impact retinal blood flow regulation is largely unknown. This study investigated whether flicker-induced vasodilation, an indicator for the coupling between neural activity and blood flow, is altered in subjects carrying the rs1061170 risk allele.
One hundred healthy subjects (aged between 18 and 45 years) were included in this study. Retinal blood flow regulation was tested by assessing retinal vessel calibres in response to stimulation with diffuse flicker light. Retinal vascular flicker responses were determined with a Dynamic Vessel Analyzer (DVA). In addition, genotyping for rs1061170 was performed.
Eighteen subjects were homozygous for the risk allele C, 50 were homozygous for the ancestral allele T, and 31 subjects were heterozygous (CT). One subject had to be excluded from data evaluation, as no genetic analysis could be performed due to technical difficulties. Baseline diameters of retinal arteries (p = 0.39) and veins (p = 0.64) were comparable between the three groups. Flicker-induced vasodilation in both retinal arteries (p = 0.38) and retinal veins (p = 0.62) was also comparable between the three studied groups.
Our data indicate that homozygous healthy young carriers of the C risk allele at rs1061170 do not show abnormal flicker-induced vasodilation in the retina. This suggests that the high-risk genetic variant of CFH polymorphism does not impact neuro-vascular coupling in healthy subjects.
已知补体因子H（CFH）酪氨酸402组氨酸（Y402H，rs1061170）变异与年龄相关性黄斑变性（AMD）显著相关。该基因变异是否会影响视网膜血流调节在很大程度上尚不清楚。本研究调查了携带rs1061170风险等位基因的受试者中，闪烁诱导的血管舒张（神经活动与血流之间耦合的一个指标）是否发生改变。
本研究纳入了100名健康受试者（年龄在18至45岁之间）。通过评估视网膜血管直径对弥漫性闪烁光刺激的反应来测试视网膜血流调节。使用动态血管分析仪（DVA）测定视网膜血管闪烁反应。此外，对rs1061170进行基因分型。
18名受试者为风险等位基因C的纯合子，50名受试者为祖先等位基因T的纯合子，31名受试者为杂合子（CT）。1名受试者因技术困难无法进行基因分析而被排除在数据评估之外。三组之间视网膜动脉（p = 0.39）和静脉（p = 0.64）的基线直径具有可比性。三组研究对象中，视网膜动脉（p = 0.38）和视网膜静脉（p = 0.62）的闪烁诱导血管舒张也具有可比性。
我们的数据表明，rs1061170处C风险等位基因的纯合健康年轻携带者在视网膜中未表现出异常的闪烁诱导血管舒张。这表明CFH多态性的高风险基因变异不会影响健康受试者的神经血管耦合。
