Influences of levodopa on expression of N-methyl-D-aspartate receptor-1-subunit in the visual cortex of monocular deprivation rats

Abstract

AIM: To detect expression of N-methyl-D-aspartate receptor-1-subunit(NMDAR1)in visual cortex of monocular deprivation rats during sensitive period and compare with that of normal group, to explore the site of NMDAR1 action in improving visual acuity and its molecular mechanism. METHODS: Sixty 14-day-old healthy SD rats were randomly divided into 4 groups including normal group, monocular deprivation(MD)group, normal saline(NS)group, levodopa(LD)group, 15 rats for each. All the rats except those in the normal group were performed monocular deprivation surgery to establish monocular deprivation animal models and were raised in normal sunlight to 45-day-old. Rats in the MD group and normal group were killed and then marked by immunohistochemical and immune protein printing, respectively. The expression of NMDAR1 in visual cortex of these two groups were measured by quantitative real time PCR method. LD and NS groups were administered with levodopa(40mg/kg)and normal saline for 28d. The expression of NMDAR1 was examined with the same method.RESULTS:NMDAR1 expression in visual cortex of MD group was lower than that in normal group. NMDAR1 expression in visual cortex of LD group was higher than that in NS group.CONCLUSION: NMDAR1 is associated with the plasticity of visual development. Levodopa may revert the reduction of expression of NMDAR1 caused by monocular deprivation. This mechanism may be related with NMDAR1 capacity of improving visual function whose site of action may lie in the parts of the visual cortex.

Keywords

• levodopa
• N-methyl-D-aspartate receptor
• monocular deprivation