Influence of destruction of retina-RPE complex on the proliferation of scleral chondrocytes in chicks

We studied the role of the retina-retinal pigment epithelium (RPE) complex in the proliferation of scleral chondrocytes in chicks. Seventy-two chicks were allocated to one of four groups: intravitreal gentamicin (400 mu g) in jection (destruction of retina-RPE complex); intravitreal gentamicin inject ion with goggling; goggling only (form-deprivation myopia); and intravitrea l saline injection (control). The chicks were killed and retina-RPE complex es were harvested under a microscope. Retina-RPE complexes were then co-cul tured with primary culture of first day scleral chondrocytes in Transwell-C OL co-culture systems (Costar), with two different pore sizes (0.4 and 3.0 mu m) and serum-deprivation medium. An MTT assay was performed at A(550) af ter 4 days. In the 0.4 mu m pore size system, the absorbency at A(550) show ed no differences between groups. However, in the 3.0 mu m pore size system , the absorbency at A(550s) (p<0.05), indicating that destruction of the re tina-RPE complex inhibited chondrocyte proliferation. The absorbency in the goggle group was higher than in the control group (p<0.05). These results indicate that the retina-RPE complex exerts a positive effect on the prolif eration of scleral chondrocytes via a molecule sized between 0.4 and 3.0 mu m in diameter.