Expression of bFGF and TGF-beta 2 in experimental myopia in chicks

PURPOSE To determine factors that control ocular enlargement in experimental form-deprivation myopia and to clarify the mechanism of form-deprivation myopia. METHODS After the left eyes of 20 chicks were monocularly occluded for 2 weeks, protein, basic fibroblast growth factor (bFGF) and transforming growth factor (TGF)-beta 2 contents in samples of constant area (circular button, diameter = 8.5 mm) in the retina-retinal pigment epithelium (RPE)-choroid and the sclera in the posterior region of control and myopic eyes were determined by enzyme-linked immunosorbent assay. RESULTS The bFGF content (per circular button) and bFGF concentration (per mg protein) were significantly lower in the sclera in the posterior region of the myopic eyes than in control eyes. The bFGF content and concentration were similar in the retina-RPE-choroid in myopic and control eyes. The TGF-beta 2 content and concentration were significantly higher in myopic eyes in both the retina-RPE-choroid and the sclera (P < 0.05). CONCLUSIONS These results are consistent with the possibility that bFGF and TGF-beta 2 regulate ocular enlargement or respond to myopiagenic mechanisms in form-deprivation myopia.