Repair of outer blood-retinal barrier after severe ocular blunt trauma in rabbits.
Retinal contusion is a leading cause of visual loss in ocular blunt trauma. However, its pathogenesis remains controversial. We established a rabbit model of severe retinal contusion with energy of about 2.87 J. Typical retinal edema and sometimes subretinal hemorrhage reproducibly occurred at the posterior pole after injury. These subsided 1 week later with depigmentation in the lesion. Histopathological examination revealed severe damage of the outer layer of retina, for example, disruption of retinal pigment epithelium (RPE) and photoreceptors. Electroretinography showed a decrease in the b wave by 38-47% in amplitudes (P < 0.01) during the first 3 days and then returned, although not to normal level. To investigate the damage and repair of blood-retinal barrier (BRB), 5 ml 2% lanthanum solution (La) was injected via the common carotid artery 1-2 min before enucleation. La diffused in the interphotoreceptor space through the damaged junctions of RPE 1 h-3 days after injury. La also reached the nuclei level of photoreceptors up to 14 days after injury. Although a glial scar with scattered RPE cells attached to Bruch's membrane in the severely damage area, no La diffusion was found in the retina 4 weeks after trauma. These results showed incomplete repair of outer BRB after severe blunt trauma.
Hui
Y N
YN
Eye Center, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China.
Wu
Y Q
YQ
Xiao
Q S
QS
Kirchhof
B
B
Heimann
K
K
D000818:Animals; D001813:Blood-Retinal Barrier; D004195:Disease Models, Animal; D004596:Electroretinography; D005131:Eye Injuries / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D005451:Fluorescein Angiography; D008297:Male; D010786:Photoreceptor Cells / Q000293:injuries / Q000648:ultrastructure; D010857:Pigment Epithelium of Eye / Q000293:injuries / Q000648:ultrastructure; D011817:Rabbits; D012160:Retina / Q000293:injuries* / Q000648:ultrastructure; D014945:Wound Healing