Preliminary study of retinal pathological features in preterm birth pups exposed to an animal model of oxygen-induced retinopathy in mice

• Published in: Graefe's archive for clinical and experimental ophthalmology 2013-08, Vol.251 (8), p.1937-1943
• Main Authors: Chu, Zhao-jie, Dou, Guo-rui, Wang, Yu-sheng, Qu, Xiao-jie, Zhang, Ye
• Format: Article
• Language: English
• Subjects: Animals; Animals, Newborn; Basic Science; Capillary Permeability; Dextrans - metabolism; Disease Models, Animal; Female; Fluorescein-5-isothiocyanate - analogs & derivatives; Fluorescein-5-isothiocyanate - metabolism; Medicine; Medicine & Public Health; Mice; Mice, Inbred C57BL; Microscopy, Confocal; Ophthalmology; Oxygen - toxicity; Pregnancy; Real-Time Polymerase Chain Reaction; Retinal Hemorrhage - diagnosis; Retinal Hemorrhage - genetics; Retinal Neovascularization - chemically induced; Retinal Neovascularization - diagnosis; Retinal Neovascularization - genetics; Retinal Vessels - metabolism; Retinal Vessels - pathology; Retinopathy of Prematurity - chemically induced; Retinopathy of Prematurity - diagnosis; Retinopathy of Prematurity - genetics; RNA, Messenger - metabolism; Vascular Endothelial Growth Factor A - genetics; Vascular Endothelial Growth Factor A - metabolism
• ISSN: 0721-832X; 1435-702X
• DOI: 10.1007/s00417-013-2366-8

Background The main risk factors of retinopathy of prematurity (ROP) are low gestational age and low birth weight, which are mainly caused by preterm birth. Currently, the animal model of oxygen-induced retinopathy (OIR) in mice is the most widely used model in ROP-associated studies. However, the experimental mice are normal-term pups, and may not mimic the pathogenic status of human ROP patients. In this study, we investigated the retinal pathological features in preterm birth pups exposed to an animal model of oxygen-induced retinopathy in mice. Methods Preterm-birth mice were obtained from pregnant C57BL/6J mice that were induced by an intraperitoneal injection of lipopolysaccharide (LPS). The preterm and control mice were treated with high oxygen (75 %) from postnatal day 7 (P7) to P12. The mice were perfused with high-molecular-weight FITC-dextran on P12, P15 and P17, and the retinas were whole-mounted and imaged. Vascular endothelial growth factor (VEGF) mRNA was also detected. Cross-sections of the retina were stained with hematoxylin and eosin (H&E) to identify preretinal neovascular tufts. For general observation, whole retinal images were also obtained using a microscope. Results Leakage of the retinal blood vessels was aggravated in the preterm mice, particularly on P12 and P15. The non-perfused areas of the retina (pixel value, 183,673 ± 28,148 vs 132,110 ± 23,732, P  = 0.009) and the number of preretinal endothelial cell nuclei were smaller (30.17 ± 8.33 vs 22.17 ± 6.74, P