Objective: To observe the effects of the L-dopa methyl ester (L-DME) on the pattern visual evoked potentials (PVEP) and expression of NGF in neurons of the visual cortex of kittens with strabismic amblyopia

and explore the therapeutic effect of L-dopa methyl ester on amblyopia and its action mechanism. Method : Thirty normal kittens were randomly divided into 6 groups: normal control

model control group

positive control (L-dopa

40 mg ·kg-1)

low dose of L-dopa methyl ester (20 mg ·kg-1)

medium dose of L-dopa methyl ester (40 mg ·kg-1)

and high dose of L-dopa methyl ester (80 mg ·kg-1). The surgery for producing iatrogenic convergent strabismus was performed on 4 week old kittens (normal control group excluded). After the confirmation of the development of amblyopia by pattern visual evoked potential

L-dopa methyl ester

L-dopa and normal saline were given to the corresponding animals respectively. The PVEP of amblyopia eyes was observed after one month

and the technique of immunohistochemical determination was used to detect the expression of nerve growth factor (NGF). Result : Compared with the normal control group

the P100 wave latency delay and the amplitude of PVEP were decreased in the model control group and the number of positive cells in the model control group was significantly reduced (P<0.05). Compared with the model control group

P100 wave latency was shortened and amplitude increased and immune-positive cells in the treatment group increased (P<0.05). Conclusion : L-dopa methyl ester can significantly improve conduction and sensory function in model of strabismic amblyopia kittens. The mechanism may be related to the increased amount of L-dopa methyl ester into the cerebral cortex and regulation of the expression of NGF.