Development of posterior capsule opacification in the rabbit.
OBJECTIVE
The aim of the present study was to characterize the development of after-cataract in the rabbit by measuring its wet weight, protein, DNA and glycosaminoglycan (GAG) contents and using Scheimpflug and slitlamp analysis. Further, aqueous humor (AqH) leukocytes, protein and lens epithelial cell proliferation activity were determined.


METHODS
AqH was collected and capsular bags including after-cataract were dissected free on days 0, 1, 7, 14, 28 and 56 after cataract surgery. The wet weights were determined and the contents of DNA, protein and GAG in the capsular bags including after-cataract were analyzed. AqH was analyzed for leukocytes, protein and proliferative activity. In another set of experiments, rabbit eyes were analyzed by the Scheimpflug technique and slitlamp examination on days 0, 1, 7, 14, 28 and 56 after cataract surgery. The wet weight of the capsular bag with the after-cataract was also determined.


RESULTS
An increase was found in the wet weight (480%) and the contents of protein (221%), DNA (945%) and GAG (336%) of the capsular bags including after-cataract during the experimental period. In the AqH, all 3 variables measured, leukocytes, protein and proliferative activity, reached their highest levels on day 1 after surgery. In the second set of experiments, the wet weight of the capsular bag including after-cataract increased by 391% during the 56-day experimental period. Posterior capsule opacification (PCO), as measured by Scheimpflug analysis, increased from 0.8 to 81.7% and the scores of Elschnig's pearls as well as fibrosis, analyzed by slitlamp, increased from 0.0 to 2.8 and 3.0, respectively.


CONCLUSIONS
This study shows that the same components that are reported to be important in human PCO are also components of PCO in the rabbit. Thus, the rabbit model seems to accurately reflect human PCO development, and because PCO develops much faster in rabbits that would make the rabbit model suitable for studies to elucidate human PCO development.
Wallentin
N
N
Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden. niklas_wallentin@merck.com
Lundgren
B
B
Holmén
J B
JB
Lundberg
C
C
D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism; D019923:Capsulorhexis; D002386:Cataract / Q000209:etiology* / Q000378:metabolism; D002455:Cell Division; D003459:Crystallins / Q000378:metabolism; D004247:DNA / Q000032:analysis; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology; D006025:Glycosaminoglycans / Q000378:metabolism; D007903:Lens Capsule, Crystalline / Q000378:metabolism / Q000473:pathology*; D019654:Lens Implantation, Intraocular; D007958:Leukocyte Count; D009929:Organ Size; D018918:Phacoemulsification; D011183:Postoperative Complications / Q000378:metabolism / Q000473:pathology*; D011817:Rabbits
D003459:Crystallins; D006025:Glycosaminoglycans; D004247:DNA