Inhibitory effects of plasminogen fragment on experimentally induced neovascularization of rat corneas.
BACKGROUND
Corneal neovascularization plays an important role in the pathogenesis of a number of corneal disorders. Recently a polypeptide was demonstrated, generated by the primary tumor, that inhibited angiogenesis and growth in metastases. This polypeptide is similar to a 38-kDa plasminogen fragment.


METHODS
We surgically implanted into rat corneal stroma a slow-release ethylene-vinyl-acetate (EVA) copolymer pellet containing basic fibroblast growth factor (bFGF) to induce corneal neovascularization. Then we applied aqueous solution containing plasminogen fragment to the rat cornea in order to observe the degree of inhibition of angiogenesis.


RESULTS
In the eyes of control rats, neovascularization from the limbus to the pellet occurred, graded 4+ in all five animals. In plasminogen fragment-treated rats, there was virtually complete inhibition of the neovascular response to the pellet. Of five treated rats, three showed no neovascularization and two demonstrated grade 1+ neovascularization. The difference in the degree of neovascularization between control and plasminogen fragment treatment was statistically significant (P < 0.05).


CONCLUSIONS
Our studies provide the first direct evidence that rat corneal neovascularization is inhibited by instillation of plasminogen fragment. This agent may prove useful in the treatment of corneal angiogenic disorder.
Murata
M
M
Department of Ophthalmology, Yamagata University School of Medicine, Japan.
Nakagawa
M
M
Takahashi
S
S
D000287:Administration, Topical; D000818:Animals; D016510:Corneal Neovascularization / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D003692:Delayed-Action Preparations; D004195:Disease Models, Animal; D005343:Fibrinolytic Agents / Q000494:pharmacology*; D016222:Fibroblast Growth Factor 2 / Q000008:administration & dosage; D009883:Ophthalmic Solutions; D010958:Plasminogen / Q000494:pharmacology*; D051381:Rats; D011921:Rats, Inbred WKY
D003692:Delayed-Action Preparations; D005343:Fibrinolytic Agents; D009883:Ophthalmic Solutions; D016222:Fibroblast Growth Factor 2; D010958:Plasminogen