Objective: To study the neuroprotection by nerve growth factor (NGF) in retina in experimental retinal detachment (RD).
Methods: Thirty one Sprague-Dawley rats were used as RD animal model by injected 0.1% sodium hyaluronate into the sub-neuroretina space. Those rats were divided into NGF experimental group, placebo group, normal control groups and pathologic control group. NGF 1 g/L/eye was injected into vitreous every 4 days in NGF experimental group and 5 micro l of PBS intravitreal injection was used as control after RD. On postoperative time 1/2 d, 1 d, 2 d, 4 d, 8 d, 16 d, 32 d, rats were sacrificed and eyes were enucleated. The effect of NGF on retina was assessed by electron, light microscopy and cell counters.
Results: Histology studies showed markedly changes in photoreceptor cells, bipolar cells and ganglion cells after RD, included depletion and shorten of inner and outer segments, disturbance and thinness of inner and outer nuclear layer and swelling of ganglion cells in NGF treated group and control. Changes in the microscopic examination in NGF group showed significantly less than that in control groups, especially in inner and outer segments of photoreceptor cells. In reattached retina, the tissue structure and cell morphology showed more close to normal in NGF group than that in RD control groups. Cell counters showed the cell numbers decreased both in NGF groups and RD control groups. When retina reattached, the cell number in experimental groups showed significantly lower than that in normal control group (P < 0.05). Nuclear number of outernuclear layer and ganglion cell layer in NGF groups was greater than that in RD control groups (P < 0.05).
Conclusion: Intravitreal injection exogenous NGF partly protects retinal cells from degeneration in experimental RD and help recovery of retinal cells after retina reattached.