Distribution and expression of RhoA in rat retina after optic nerve injury

BACKGROUND: RhoA is a small guanosine triphosphatase which participates in signaling pathways of axonal repellents or inhibitors. However, the distribution and expression of RhoA in the rat retina after optic nerve injury has not been elucidated yet. OBJECTIVES: To study the distribution and expression of RhoA in the rat retina after optic nerve injury. METHODS: Immunohistochemistry was used to determine the distribution of RhoA in rat retina after optic nerve injury. The expression of RhoA was analyzed by Western blot. RESULTS: In normal retina and the retina 1 day after optic nerve injury, RhoA was distributed in the retinal ganglion cell (RGC) layer. Three days after optic nerve injury, it existed in RGCs and the inner plexiform layer. However, 7 days after surgery its immunoreactivity was abundant not only in the RGC and inner plexiform layers but also in the inner nuclear and outer plexiform layers. Western blot analysis showed that the expression of RhoA increased significantly in the retina after optic nerve injury in comparison with normal retina. CONCLUSION: These results indicate that the distribution and expression of RhoA were extended and enhanced after optic nerve injury, and that RhoA plays an important role in optic nerve regeneration.