Expression of collapsin response mediator protein 2 in visual cortex of form deprivation amblyopic rats

Abstract

Objective To study the expression of collapsin response mediator protein 2 (CRMP-2) in the visual cortex of monocular form deprivation amblyopia rats. Methods Sixty-four 14-day-old rats were randomly divided into monocular deprivation amblyopia group and normal control group by random number table method.Right eyelid margin suture was performed at 14 days after birth in the monocular deprivation amblyopia group.Eight rats in the monocular deprivation amblyopia group and the normal control group were observed at 14, 21, 45 and 120 days after birth, respectively.Flash visual evoked potential (F-VEP) was used to dectect the latency and amplitude of P1 wave.The expression of CRMP-2 in visual cortex was observed by immunohistochemical method.The use and care of the animals complied with Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission.This study protocol was approved by Ethic Committee of the University of South China (No.20140228). Results F-VEP results showed that the amplitudes of P1 were decreased and latent periods of P1 were prolonged in the monocular deprivation amblyopia group compared with the normal control group (t=16.760, P=0.000; t=-22.919, P=0.000). CRMP-2 expression levels in the visual cortex of monocular deprivation amblyopia groups and normal control groups were compared at different time points after birth, and the differences were statistically significant (Fgroup=8.855, P=0.010; Ftime=63.091, P=0.000). Compared with normal control groups, the expressions of CRMP-2 at the postnatal 21, 45 and 120 days were obviously decreased in the monocular deprivation amblyopia groups, the differences were statistically significant (all at P<0.05). Conclusions CRMP-2 may be involved in the occurrence and development of amblyopia. Key words: Collapsin response mediator protein 2; Form deprivation amblyopia; Rat; Visual cortex