Effects of l-dopa methyl ester on visual cortex injury induced by amblyopia and its underlying mechanism

Amblyopia is related to the impairment of visual system, especially visual cortex. l-Dopa has been reported to treat the disease, but the effect of its derived methyl ester has not been investigated. Therefore this study assessed the anatomic and physiologic effects of 30 days' treatment of l-dopa methyl ester at different doses on visual cortex area 17 in feline model with amblyopia induced by monocular vision deprivation. Immunohistochemical staining and Western blot were used to examine the structural changes of nerve cells and the expression of nerve growth factor (NGF), respectively. Comparing to the control, l-dopa methyl ester intervention significantly increased the number and density of NGF-immunoreactive cells, elevated endogenous NGF expression in visual cortex and promoted neural regeneration. The results suggest that l-dopa methyl ester can effectively inhibit amblyopia process via a mechanism that may involve increasing endogenous NGF expression and promoting neural repairment in visual cortex area 17.