Following granulocyte colony-stimulating factor (G-CSF) treatment, the growth of processes in cultured rat retinal ganglion cells (RGCs) in vitro, expression of growth associated protein 43, and expression of microtubule-associated protein 2 mRNA expression were significantly increased. In contrast, RhoA/Rock protein content was significantly reduced by G-CSF treatment. These results indicate that G-CSF promotes the growth of processes in RGCs and increases the expression of growth-associated protein 43 and microtubule-associated protein 2 mRNA by inhibiting the RhoA/Rock pathway, thereby benefiting axonal repair in RGCs exposed to hypoxia.rn