Effect of vascular endothelial growth factor on retinal ganglion cells of rats with chronic intraocular hypertension.

AIM: To investigate the effect of vascular endothelial growth factor (VEGF) on the expression of pigment epithelium-derived factor (PEDF) in retina and the protective effect of VEGF on retinal ganglion cells (RGCs) of rats with chronic elevated intraocular pressure (EIOP) and it's potential mechanism.

METHODS

30 females Sprague-Dawley rats were randomly divided into three groups: EIOP + VEGF group (A), EIOP + vehicle group (B) and sham operated + VEGF group (C). The EIOP was introduced by obstructing episcleral veins in Group A and Group B. In the Group C, only the bulber conjunctiva was opened without obstructing episcleral veins. Immediately after surgery, rats in the Group A and Group C were intravitreously injected with 2 μL of VEGF. In the Group B, rats were intravitreously treated with 2 μL of normal saline. At 3 and 14 days after injection, animals were sacrificed and the eyes were collected for preparation of frozen sections.

RESULTS

After surgery, the IOP increased significantly in the Group A and Group B. There was no significant difference in the IOP at day 3 and day 14 after operation. The PEDF expression in the Group A and Group B was higher than that in the Group C. TUNEL staining showed the apoptotic RGCs markedly reduced after VEGF treatment when compared with rats without treatment.

CONCLUSION

Intravitreal treatment with VEGF may reduce the apoptosis of RGCs in rats with chronic intraocular hypertension.