Hernández C, Lecube A, Segura R M, Sararols L, Simó R
Diabetes Unit, Endocrinology Division, Hospital General Universitari Vall d'Hebron, Pg. Vall d'Hebron 119-129, 08035 Barcelona, Spain.
Diabet Med. 2002 Aug;19(8):655-60. doi: 10.1046/j.1464-5491.2002.00768.x.
Several reports have implicated nitric oxide (NO) in the angiogenic process. The assessment of NO stable end products, nitrite and nitrate (NOx), is commonly used as a measure of NO production in biological fluids. The aims of the study were to investigate NOx concentrations in the vitreous fluid of patients with proliferative diabetic retinopathy (PDR) and to evaluate the relationship between NOx and vascular endothelial growth factor (VEGF).
Serum and vitreous fluid samples were obtained simultaneously at the time of vitreoretinal surgery from 23 patients with PDR, and 17 control non-diabetic patients with non-proliferative ocular disease. NOx was determined by using the Griess reaction and VEGF levels were assessed by ELISA.
The intravitreous concentration of NOx was significantly elevated in patients with PDR in comparison with the control group (31.6 +/- 2.96 micromol/l vs. 18 +/- 2.46 micromol/l; P = 0.01). However, we did not detect any differences between NOx serum concentrations. We observed a correlation between serum and vitreous levels of NOx in diabetic patients (r = 0.79; P < 0.001), but not in the control group. Intravitreous levels of VEGF in patients with PDR were higher than those obtained in serum (1.42 ng/ml (0.12-7.62) vs. 0.12 ng/ml (0.03-0.42); P < 0.01). Vitreal levels of VEGF were strikingly higher in patients with PDR than in the control subjects (1.42 ng/ml (0.12-7.62) vs. 0.009 ng/ml (0.009-0.04); P < 0.001). No correlation between vitreal concentrations of NOx and VEGF was observed, either in diabetic patients or in the control group.
NOx and VEGF are increased but not related in the vitreous fluid of diabetic patients with PDR. Our results suggest that serum diffusion could play a significant role in explaining the increase of NOx. By contrast, intraocular production seems to be the main factor responsible for the intravitreous enhancement of VEGF.
多项报告表明一氧化氮（NO）参与血管生成过程。评估NO的稳定终产物亚硝酸盐和硝酸盐（NOx），通常用于衡量生物体液中NO的生成量。本研究的目的是调查增殖性糖尿病视网膜病变（PDR）患者玻璃体液中的NOx浓度，并评估NOx与血管内皮生长因子（VEGF）之间的关系。
在玻璃体视网膜手术时，同时采集23例PDR患者以及17例非糖尿病性非增殖性眼病对照患者的血清和玻璃体液样本。采用格里斯反应测定NOx，通过酶联免疫吸附测定法评估VEGF水平。
与对照组相比，PDR患者玻璃体内NOx浓度显著升高（31.6±2.96微摩尔/升对18±2.46微摩尔/升；P = 0.01）。然而，我们未检测到NOx血清浓度之间存在任何差异。我们观察到糖尿病患者血清和玻璃体内NOx水平之间存在相关性（r = 0.79；P < 0.001），但对照组未观察到这种相关性。PDR患者玻璃体内VEGF水平高于血清中的水平（1.42纳克/毫升（0.12 - 7.62）对0.12纳克/毫升（0.03 - 0.42）；P < 0.01）。PDR患者的玻璃体内VEGF水平显著高于对照组（1.42纳克/毫升（0.12 - 7.62）对0.009纳克/毫升（0.009 - 0.04）；P < 0.001）。在糖尿病患者或对照组中，均未观察到玻璃体内NOx浓度与VEGF之间存在相关性。
PDR糖尿病患者玻璃体液中NOx和VEGF升高，但两者无相关性。我们的结果表明，血清扩散可能在解释NOx升高方面起重要作用。相比之下，眼内生成似乎是玻璃体内VEGF升高的主要因素。
