Pericytes are correlated with the permeability of rat corneal neovascular vessels induced by alkali burn.
BACKGROUND
Corneal neovascular leakage can lead to edema and secondary scarring. Previous studies have shown that pericytes play a key role in maturation of angiogenesis. The present studies investigate the relationship between vascular permeability and pericyte coverage of endothelial cells in rat corneal neovascular induced by alkali burns.


METHODS
Corneal neovascular vessels induced by alkali burns was performed in Sprague-Dawley rats. Corneas were excised on 1, 2, 3, 5, 7 and 10 days after cauterization. The vascular permeability rate was measured by the Evans blue method. The microvessel pericyte coverage index (MPI) was applied to quantify the pericyte coverage through double immunofluorescent staining of frozen sections of corneas with CD31 as the endothelial and alpha-smooth muscle actin (alpha-SMA) as the pericyte markers. The correlation between permeability rate and MPI was analyzed. Pericyte coverage was confirmed ultrastructually using transmission electron microscopy.


RESULTS
The vascular permeability rate was (1.14 +/- 0.17), (0.24 +/- 0.08), (0.29 +/- 0.16), (0.14 +/- 0.10), (0.09 +/- 0.06) and (0.05 +/- 0.04) microg x ml(-1) x mm(-2) respectively on 1, 2, 3, 5, 7 and 10 days after cauterization. The MPI was 0, 16.07%, 11.95%, 43.84%, 73.97% and 86.21% respectively at the above mentioned time points. The correlation coefficient between MPI and the permeability rate was -0.943 (P = 0.005).


CONCLUSIONS
Pericyte recruitment was significantly correlated with the permeability of corneal neovascularization induced by alkali burns in rats. Therapeutic strategies aiming at anti-leakage should be most effective if they promote pericytes proliferation in the course of corneal neovascularization.
Zhao
Wei
W
Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China.
Jiang
Ai-hua
AH
Li
Chao-yang
CY
Yang
Wen-zhao
WZ
Xu
Chuan-chao
CC
Liu
Zu-guo
ZG
D000468:Alkalies; D000818:Animals; D002057:Burns, Chemical / Q000503:physiopathology*; D002199:Capillary Permeability; D002465:Cell Movement; D003315:Cornea / Q000098:blood supply / Q000648:ultrastructure; D016510:Corneal Neovascularization / Q000503:physiopathology*; D005126:Eye Burns / Q000139:chemically induced / Q000503:physiopathology*; D005260:Female; D005455:Fluorescent Antibody Technique; D020286:Pericytes / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D000468:Alkalies