Related Experiment Video
Updated: Apr 22, 2026
Oxygen-Induced Retinopathy Model for Ischemic Retinal Diseases in Rodents
Published on: September 16, 2020
Influence of the difference of breastfeeding volume on a rat model of oxygen-induced retinopathy
Michiko Matsubara1, Yuta Saito1, Takako Nakanishi-Ueda2
1Department of Ophthalmology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan.
Insights
Abundant breast milk intake improved body weight gain and retinal development in oxygen-induced retinopathy (OIR) rat models. However, excess milk had minimal impact on retinal vascularization in this study.
Area of Science:
- Neonatal physiology
- Ophthalmology
- Developmental biology
Background:
- Oxygen-induced retinopathy (OIR) is a significant cause of vision impairment in premature infants.
- Breast milk composition and intake levels can influence neonatal development and disease outcomes.
- Understanding the impact of milk intake on OIR is crucial for potential therapeutic strategies.
Purpose of the Study:
- To investigate the effects of abundant breast milk intake on an OIR rat model.
- To assess the impact of litter size, reflecting milk availability, on OIR progression.
- To evaluate key physiological and ocular parameters in response to varying milk intake.
Main Methods:
- Neonatal Sprague-Dawley rats were divided into litters of 7 or 14 pups.
- Rats were exposed to 80% oxygen from postnatal day 0 to 12 to induce OIR.
- Body weight, serum insulin-like growth factor-1 (IGF-1), retinal vascular endothelial growth factor (VEGF), and retinal morphometrics (neovascularization score, total retinal area, avascular area, vascularized area) were analyzed.
Main Results:
- Rats in smaller litters (7 pups/litter) exhibited significantly greater body weight gain from postnatal day 2.
- Serum IGF-1 levels were significantly higher in the 7-rats group at postnatal days 13 and 18.
- Retinal VEGF and total retinal area at postnatal day 18 were significantly larger in the 7-rats group; neovascularization score tended to be higher, while vascularized area showed no significant difference.
Conclusions:
- Abundant breast milk intake, simulated by smaller litter sizes, promotes body weight gain and enhances overall retinal development in OIR rat pups.
- While promoting growth and development, excess milk intake demonstrated a limited effect on the extent of retinal vascularization in this OIR model.
- Further research is needed to elucidate the precise mechanisms and potential clinical implications of milk intake on OIR pathogenesis and management.
Abstract:
This study aimed to investigate the effects of abundant breast milk intake on rats model of oxygen-induced retinopathy (OIR). Neonatal Sprague-Dawley rats were randomly assigned to expand litters of 7 pups/litter (7-rats group) and 14 pups/litter (14-rats group). They were exposed to 80% oxygen from postnatal day (P) 0 to P12. Body weights were measured daily. At P13 and 18, rats were sacrificed, and the blood and eyes were collected. Retinal neovascularization (NV) score, total retinal area (TRA), avascular area (AVA), and vascularized area (VA) were measured in ADPase stained retinas. Retinal vascular endothelial growth factor (VEGF) and serum insulin-like growth factor (IGF-1) were measured using ELISA. Body weight gain was significantly greater in 7-rats group from P2. Serum IGF-1 levels at P13 and 18 were significantly higher in 7-rats group. Retinal VEGF and TRA at P18 were significantly larger in 7-rats group. NV score at P18 tended to be higher in 7-rats group. There was no significant difference in VA between the 2 groups at P13 and 18. Excess breast milk intake in OIR rat pups caused body weight gain and retinal development, whereas there was less effect on retinal vascularization in our study.
