Possible Involvement of Nitric Oxide in the Progression of Diabetic Retinopathy

• Published in: Ophthalmologica (Basel) Vol. 217; no. 5; pp. 342 - 346
• Main Authors: Tsai, Der-Chong, Chiou, Shih-Hwa, Lee, Fenq-Lih, Chou, Ching-Kuang, Chen, Shih-Jen, Peng, Chi-Hsien, Kuo, Yao-Haur, Chen, Chieh-Fu, Ho, Larry L.-T., Hsu, Wen-Ming
• Format: Journal Article
• Language: English
• Published: Basel, Switzerland Karger 01.09.2003; S. Karger AG
• Subjects: Aged; Aqueous Humor - metabolism; Associated diseases and complications; Biological and medical sciences; Cataract - metabolism; Diabetes. Impaired glucose tolerance; Diabetic Retinopathy - metabolism; Diabetic Retinopathy - physiopathology; Disease Progression; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Humans; Luminescent Measurements; Medical sciences; Middle Aged; Nitric Oxide - metabolism; Original Paper; Retinal Neovascularization - metabolism; Retinal Neovascularization - physiopathology; Diabetic retinopathy; Plasma; Chemiluminescence; Aqueous humor; Nitric oxide; Endocrinopathy; Human; Concentration factor; Retinopathy; Pathophysiology; Diabetes mellitus; Blood plasma; Eye disease
• ISSN: 0030-3755; 1423-0267
• DOI: 10.1159/000071349

Abnormal nitric oxide (NO) synthesis has been implicated in the pathogenesis of diabetes mellitus. The aim of our study was to elucidate the relationship between the stages of diabetic retinopathy (DR) and the NO levels in aqueous humor and plasma. Using the chemiluminescence assay, we measured the concentrations of NO in aqueous humor and plasma samples obtained during intraocular surgery from 45 diabetic patients and 19 nondiabetic cataract patients. The patients with diabetes were classified into 4 groups: proliferative DR (PDR) with active neovascularization (active PDR; 9 cases), PDR with quiescent neovascularization (regressed PDR; 6 cases), background DR (BDR; 16 cases) and no DR (14 cases). We found that the aqueous NO levels (mean ± SE) of the active PDR group (83.2 ± 13.9 µM) were significantly higher than those of the BDR group (45.8 ± 6.0 µM, p = 0.049) and the diabetics without DR (33.3 ± 5.2 µM, p = 0.011), and, although not statistically significantly, they were also higher than those of the regressed PDR group (52.1 ± 10.3 µM, p = 0.224). However, no significant differences were observed between any of the diabetic subgroups in the plasma NO levels (p = 0.345). We therefore concluded that NO present in the ocular tissues may play important roles in the progression of DR.