Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark.
Acta Ophthalmol. 2011 Dec;89(8):764-8. doi: 10.1111/j.1755-3768.2009.01847.x. Epub 2010 Mar 19.
Diabetic retinopathy is characterized by morphological changes in the retina secondary to disturbances in retinal blood flow. It has been shown that antihypertensive treatment has a protective effect on the development of diabetic retinopathy, and evidence suggests that inhibitors of the renin-angiotensin system have a protective effect beyond the antihypertensive effect. The background for this additional effect is unknown but might be related to an effect on retinal autoregulation.
In a double-blinded, two-way cross-over study, 25 normotensive patients with type 1 diabetes (T1D) aged 20.6-33.9 (mean 27.9) with mild retinopathy were randomized to receive either 5 mg of the calcium channel blocker (CCB) amlodipine for 14 days followed by a washout period and treatment with 10 mg of the angiotensin converting enzyme (ACE) inhibitor lisinopril for another 14 days or the two treatments in the reverse order. Using a Dynamic Vessel Analyzer (DVA), the diameter response of retinal arterioles during an acute increase in the blood pressure induced by isometric exercise, during flicker stimulation and during both stimulus conditions simultaneously was studied before and during the two treatments periods.
Amlodipine and lisinopril induced a similar non-significant decrease in the arterial blood pressure. At baseline, the arterial diameter decreased by 2.4 ± 0.9% (p = 0.004) during isometric exercise, increased by 2.2 ± 0.9% (p = 0.019) during flicker stimulation and increased by 1.8 ± 0.9% (p = 0.03) during the combined stimulus conditions. Neither of the antihypertensive drugs amlodipine (p = 0.76) or lisinopril (p = 0.11) changed the diameter response of retinal vessels significantly; however, the two treatments induced a different response in the veins during combined exercise and flicker (p = 0.021).
Short-term treatment with amlodipine and lisinopril had no significant effect on retinal autoregulation in young normotensive patients with T1D and mild retinopathy, and this lack of effect was similar for the two drugs. A possible normalizing effect of antihypertensive treatment on retinal autoregulation was not observed; however, it might take longer time to improve autoregulation than to reduce the arterial blood pressure.
糖尿病视网膜病变的特征是视网膜形态发生变化，这是由于视网膜血流紊乱引起的。已经表明，降压治疗对糖尿病视网膜病变的发展具有保护作用，并且有证据表明，肾素-血管紧张素系统抑制剂除了具有降压作用外，还具有保护作用。这种额外作用的背景尚不清楚，但可能与视网膜自身调节的作用有关。
在一项双盲、双向交叉研究中，25 名年龄在 20.6-33.9 岁（平均 27.9 岁）、患有轻度视网膜病变的 1 型糖尿病（T1D）的非高血压患者被随机分为两组，分别接受 14 天的 5mg 钙通道阻滞剂（CCB）氨氯地平治疗，然后进行洗脱期，再接受 14 天的 10mg 血管紧张素转换酶（ACE）抑制剂赖诺普利治疗，或者两种药物以相反的顺序进行治疗。使用动态血管分析仪（DVA），在两种治疗期间，在等长运动引起的血压急性升高期间、在闪烁刺激期间以及在两种刺激条件同时进行期间，研究了视网膜小动脉的直径反应。
氨氯地平和赖诺普利均引起动脉血压的非显著性降低。在基线时，等长运动期间动脉直径降低 2.4±0.9%（p=0.004），闪烁刺激期间增加 2.2±0.9%（p=0.019），联合刺激条件下增加 1.8±0.9%（p=0.03）。两种降压药物氨氯地平（p=0.76）或赖诺普利（p=0.11）均未显著改变视网膜血管的直径反应；然而，两种治疗方法在联合运动和闪烁刺激期间对静脉产生了不同的反应（p=0.021）。
短期应用氨氯地平和赖诺普利对年轻的、患有 1 型糖尿病和轻度视网膜病变的非高血压患者的视网膜自身调节没有显著影响，这两种药物的作用相似。没有观察到降压治疗对视网膜自身调节的正常化作用；然而，改善自身调节可能需要比降低动脉血压更长的时间。
