| Objectives: To evaluate the effects of ES eyedrops on the corneal neovascularization and corneal allograft rejection by topical installition on the rat model of penetrating keratoplasty, and to investigate its possible mechanism and its clinical signification.Methods: Penetrating keratoplasty(PKP) was proformed orthotopically from Wistar rats to SD rat'recipients. 60 SD rats were randomly assigned to two groups-experimental group and control group after PKP. The experimental group was treated with ES eyedrops, the control group was treated with escipient eyedrops. The rejection time and survival time were recorded and compared by the biomicroscope examination. The corneal opacity, edema and CNV were also recorded and compared, and then calculate the animals'rejection index. The area of CNV was calculated quantitatively. 6 animals in both groups were killed respectively at the 1st week, 2nd week, 3rd week, 1st month and 2nd month postoperatively. CNV and inflammation were evaluated with HE staining. ES and VEGF expression was examined by immunohistochemistry. Corneal ultrastructural morphology was observed by TEM. FCM analysis was used to identify the kinetic variation of the peripheral T cell population CD4~+, CD8~+ and CD4~+/CD8~+ ratio.Results: 1. The mean survival time of the allografts in the control group was 13.3±3.3 days, but the mean survival time of the allografts in the experimental group was 23.2±4.3 days, which was obviously longed as compared with the control group (P<0.01). 2. The area of CNV was inhibited by 1 week, 2 weeks, 3 weeks, 1 month and 2 months (P<0.05 or P<0.01). 3. The rejection index of the experimental group was lower obviously than the control group by 1 week, 2 weeks, 3 weeks, 1 month and 2 months (P<0.05 or P<0.01). 4. The experimental group has less neovascularization and inflammatory infiltration than the control group,but more apoptosis of vascular endothelial cell . 5. Significantly increased ES expression was observed in the experimental group compared with the control group by immunohistochemistry staining. 6. Significantly decreased VEGF expression was observed in the experimental group compared with the control group by immunohistochemistry staining. 7. In comparing with the control group, the peripheral CD4+ and CD4+/CD8+ ratio in the experimental group were decreased significantly. Conclusions: 1. Topical application of ES eyedrops can prolong survival time of the allografts. 2. The area of CNV was decreased by topical application of ES eyedrops and ES can prevent vascular growth of corneal allografts. Then ES eyedrops suppressed effectively the postoperative corneal allograft rejection according to the rejection index. 3. ES eyedrops can enhance ES expression in corneal allografts. 4. ES eyedrops can reduce VEGF expression in corneal allografts and then suppress the corneal allograft rejection. 5. The peripheral CD4~+ and CD4~+/CD8~+ ratio was decreased obviously by the application of ES eyedrops.
|
PDF Full Text Request