[Hyperoxia-induced retinal peroxidative injury in immature rats].
OBJECTIVE
To investigate the role of oxidative stress in the pathogenesis of retinal injury induced by hyperoxia.


METHODS
Sixty immature Sprague-Dawley (SD) rats born at a gestational age of 21 days, were randomly exposed to room air (air group, n=30) or 95% oxygen (hyperoxia group, n=30) immediately after birth. Plasma 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha) levels were determined by ELISA. The ultrastructures of the retina were observed under a transmission electron microscope.


RESULTS
The plasma 8-iso-PGF2alpha contents of the air group were 19.09 +/-5.57, 18.24+/-5.91 and 17.00 +/- 5.58 pg/mL on the 3rd, 7th and 14th days after birth, respectively (F=1.024, P> 0.05). The plasma 8-iso-PGF2 contents in the hyperoxia group on the 3rd (28.33 +/- 5.59 pg/mL), the 7th day (51.20 +/- 15.01 pg/mL) and 14th day (84.54 +/- 14.85 pg/mL) after birth were significantly higher than those of the air group (t=2.863, P< 0.05; t=5.073, P< 0.01; t=11.006, P< 0.01). Moreover, the plasma 8-iso-PGF2 contents in the hyperoxia group increased with the prolonged hyperoxia exposure (F=150.7, P < 0.01). The ultrastructures of retina in the air group were normal. Hyperoxia exposure resulted in abnormalities of the ultrastructures of retina, manifesting as the membrane discs rarefied, twisted and disrupted and mitochondrial swelling.


CONCLUSIONS
Oxidative stress can results in retinal injury in immature rats. An increased plasma level of 8-iso-PGF2alpha is related to the injury degree of retina.
Zhou
Dong
D
Department of Neonatology, First Affiliated Hospital of Jinan University, Guangzhou, China.
Zhong
Jing-Xiang
JX
Xiao
Xin
X
Liu
Xiu-Xiang
XX
Zhu
Chun-Ling
CL
D000818:Animals; D015237:Dinoprost / Q000031:analogs & derivatives / Q000097:blood; D006801:Humans; D018496:Hyperoxia / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D007231:Infant, Newborn; D015227:Lipid Peroxidation; D018384:Oxidative Stress; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D012178:Retinopathy of Prematurity / Q000209:etiology
C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost