A total of 48 guinea pigs were randomly divided into control group， model group， low concentration of NGF group and high concentration of NGF group（n=12）. In addition to control group， the FDM models of guinea pigs in other groups were established by wearing lens with 10.0 diopter （D） in the right eyes， and the left eyes were not treated. The guinea pigs in low and high concentrations of NGF groups were respectively injected with 500 and 1 000 BU NGF in the right eyes for 21 d. The D and axial lengths of eyes of the guinea pigs in various groups were measured by infrared eccentric optometer and ophthalmic A/B ultrasound diagnostic apparatus. HE staining was used to observe the pathomophology of scleral tissue of the guinea pigs in various groups. Real-time fluorescence quantificative PCR （RT-qPCR） method was used to detect the expression levels of glycogen synthase kinase-3β（GSK-3β），β-catenin， and vascular endothelial growth factor （VEGF） mRNA in scleral tissue of the guinea pigs in various groups. Immunohistochemistry was used to detect the rates of GSK-3β and β-catenin positive cells in scleral tissue of the guinea pigs in various groups.Western blotting method was used to detect the expression levels of GSK-3β and β-catenin proteins in scleral tissue of the guinea pigs in various groups.

Compared with model group， the D of right eyes of the guinea pigs in low and high concentrations of NGF groups were increased significantly （P<0.05）， while the axial lengths of eyes were decreased significantly （P<0.05）.The HE staining results showed that the thickness of scleral tissue of the guinea pigs in model group were decreased， the collagen fibers were disordered， and the obvious interstitial spaces appeared between the fibers； the thickness of sclera tissue of the guinea pigs in low and high concentrations of NGF groups were increased， and the structures were relatively clear. Compared with model group， the expression levels of GSK-3β mRNA and protein in scleral tissue of right eyes of the guinea pigs in low and high concentrations of NGF groups were significantly decreased （P<0.05）， while the expression levels of VEGF and β-catenin mRNA and protein were significantly increased （P<0.05）.

The exogenous NGF can protect the scleral tissue of the guinea pigs with FDM by regulating the Wnt/β-catenin signaling pathway， inhibiting the expression of GSK-3β and increasing the expression of β-catenin.