目的：研究增殖性糖尿病视网膜病变(proliferative diabetic retinopathy，PDR)患者血液、房水、玻璃体中血管内皮生长因子(vascular endothelial growth factor，VEGF)含量的变化，探讨VEGF与PDR的关系，为抗VEGF药物治疗的给药途径及剂量等提供理论依据。

方法：采用双抗体夹心酶联免疫吸附测定法定量检测无糖尿病视网膜病变(NDR)组，单纯性糖尿病视网膜病变(BDR)组，增殖性糖尿病视网膜病变(PDR)组患者和正常对照组血浆中VEGF含量，还检测PDR患者房水、玻璃体中和正常对照组房水、玻璃体中VEGF含量，并进行综合分析。试剂盒购自美国R&D公司，其质量和灵敏度相对较高。

结果：PDR组房水中VEGF含量有增高趋势，但与正常对照组比较，无统计学差异(P>0.05)。PDR患者玻璃体中VEGF含量明显增高，与正常对照组比较差异非常显著(P<0.01)。PDR组自身血浆、房水、玻璃体中VEGF含量比较有逐渐增高趋势，三者之间有显著性差异(P<0.01)。正常对照组血浆、房水、玻璃体中VEGF含量三者之间无显著性差异(P>0.05)。血浆VEGF含量在正常对照组中最高，而玻璃体中VEGF含量在PDR患者中最高。

结论：PDR患者眼内尤其是玻璃体中VEGF含量大幅度增高，可能对促进DR发展恶化起了关键性的作用。在正常人，VEGF更多地存在于血浆中发挥其生物学效应。在严重DR患者中，玻璃体中异常地出现大量VEGF，推测来自缺血缺氧的视网膜，并可能有向眼前段扩散的趋势。

AIM: To determine the relations between the changes of vascular endothelial growth factor(VEGF)concentration in plasma, aqueous humor and vitreous of patients with diabetic retinopathy(DR)and proliferative diabetic retinopathy(PDR), as well as to find if the condition of metabolism control of patients with DR may affect the VEGF level.

METHODS: Double antibody sandwich enzyme-linked immunosorbent assay was used to measure the levels of VEGF concentration in plasma of non-diabetic retinopathy(NDR)patients group, background diabetic retinopathy(BDR)patients group, and proliferative diabetic retinopathy(PDR)patients group. The levels of HbAlc in plasma of patients in above three groups were measured at the same time. The VEGF concentration in aqueous humor, vitreous of PDR patients group and normal group was also measured for further comprehensive analysis. Human VEGF immunoassay Quantikine with high sensibility and quality was imported from R& D Co. LTD., USA.

RESULTS: There was an increasing tendency in the VEGF concentration in aqueous humor of PDR patients group. There was no statistically significant difference as it was compared with normal group(P>0.05). The VEGF concentration in vitreous of PDR patients group was obviously increased, there was significant difference as it was compared with normal group(P<0.01). It showed an increasing tendency of VEGF concentration in turn in plasma, aqueous humor and vitreous of the 3 PDR patients selves. It showed that there was significant difference among VEGF concentration in plasma, aqueous humor and vitreous of all the PDR patients(P<0.01). In normal group there was no significant difference among VEGF concentration in plasma, aqueous humor and vitreous(P>0.05). In normal group the VEGF concentration in plasma was the highest, but in PDR patients group the VEGF concentration in vitreous was the highest.

CONCLUSION: The significantly increased VEGF concentration in eyes, especially in vitreous of PDR patients may play an important role in development and deterioration of DR. It was clear that VEGF played its normal biological functions mainly in plasma in normal human. In severe DR patients, abnormal high may come from ischemic and VEGF concentration in vitreous suggested that it hypoxic retina and there was a tendency to diffuse towards the front of eyes.