ARC/Arg3.1 expression in the lateral geniculate body of monocular form deprivation amblyopic kittens

Abstract

Purpose: The present study compared the expression of activity-regulated cytoskeleton-associated protein (ARC/Arg3.1) in the lateral geniculate body between form deprivation amblyopia kittens and normal kittens to examine the significance of ARC/Arg3.1 in the lateral geniculate body in the pathogenesis of amblyopia.

Methods: Twenty kittens were randomly divided into an experimental group (n = 10) and a control group (n = 10). Black opaque covering cloth was used to cover the right eye of kittens in the experimental group. Pattern visual evoked potentials (PVEP) were detected weekly in all kittens. The expression of the ARC/Arg3.1 gene was detected by immunohistochemistry and in situ hybridization, and apoptosis of lateral geniculate body cells was detected by TUNEL.

Results: PVEP detection showed that at the age of 5 and 7 weeks, the latency of P100 in the right eye of the experimental group was higher than that of the other three groups (P < 0.05), and the amplitude of P100 was lower than that of the other three groups (P < 0.05). The expression of ARC/Arg3.1 protein (P < 0.05) and mRNA (P < 0.05) in the lateral geniculate body of the experimental group was significantly lower than that of the control group. The level of neuronal apoptosis in the experimental group was higher than that in the control group (P < 0.05). The expression of the ARC/Arg3.1 gene was negatively correlated with the apoptosis level of lateral geniculate body neurons.

Conclusions: The expression of ARC/Arg3.1 is associated with monocular form deprivation amblyopia and apoptosis of lateral geniculate body cells.

Keywords: Activity-regulated cytoskeleton-associated (ARC/Arg3.1); Amblyopia; Form deprivation; Lateral geniculate body.

Fig. 1

Anatomical schematic diagram of the lateral geniculate body. According to the direction of the optic tract (blue arrow), the lateral geniculate body (black arrow) can be seen and separated

Fig. 2

The latency and amplitude trend of P100 waves in 3-week-old to 7-week-old kittens. With the increase of age, the latency showed an upward trend (A) and the amplitude of each group showed a downward trend (B). At 5 and 7 weeks of age, the latency and amplitude of the right eye in the experimental group were statistically different from those in the other three groups

Fig. 3

PVEP waves of each group of kittens after covering the right eye of the experiential group for 4 weeks. The latency in the right eye of the experimental group (C) was longer, and the amplitude was lower than in the right eye of the control group (A), the left eye of the control group (B), and the left eye of the experimental group (D)

Fig. 4

Immunohistochemical performance in the lateral geniculate body in each group (DAB X400). The black arrow in the picture indicates positive cells. The protein of ARC/Arg3.1 positive expression in the cytoplasm of neurons was brown-yellow. At the age of 7 weeks, there were more positive cells in the control group (A) and fewer in the experimental group (B)

Fig. 5

In situ hybridization performance in the lateral geniculate body in each group (DAB X400). The black arrow in the picture indicates positive cells. The protein of ARC/Arg3.1 positive expression in the cytoplasm of neurons was brown-yellow. At the age of 7 weeks, there were more positive cells in the control group (A) and fewer in the experimental group (B)

Fig. 6

TUNEL performance in the lateral geniculate body in each group (DAB X400). TUNEL-positive cells were brown-yellow, while TUNEL-negative cells were blue. The black arrow in the picture indicates the positive cells. At 7 weeks of age, there were fewer TUNEL-positive cells in the control group (A) and more TUNEL-positive cells in the experimental group (B)