Fig. 6.
Folic acid ([FA] 80 μg/kg intraperitoneally) markedly increases the number of (Fluorogold-positive) retinal ganglion cells that regenerate axons (protocol 3b) compared with no folic acid control retinal ganglion cells (protocol 3a), and to serial 80% N2O exposure retinal ganglion cells (protocol 3c). Serial exposure to 80% N2O (protocol 3d) reverses the benefit of serial folic acid administration. Table 4 provides the number of animals used to compare the regenerating retinal ganglion cells after sharp optic nerve injury.