AIM: To make a rat model of optic nerve injury by using the transverse quantitative traction method, and to evaluate the survival rate of retinal ganglion cells(RGCs)of the model using the method of fluorogold retrograde labeling.

METHODS:Twenty-five Wistar rats were randomly divided into five groups: sham operation group, 1d, 3d, 7d and 14d after tractive optic nerve injury group. The model groups pulled the left optic nerve with lateral tensiometer; the sham operation group only exposed the optic nerve but not pulled. The right eyes of each group were served as normal control eyes. The RGCs density of the five groups was observed by fluorogold retrograde labeling.

RESULTS:In the normal control group, the RGCs labeled by the fluorescent gold were round or oval, clear boundary, no obvious fluorescent dye leakage and partially visible cell processes. However, in the optic nerve traction groups, the number of RGCs decreased with time increasing and the cell distribution was not uniform. Lots of fluorescent leakages and microglial cells were observed. Compared with the normal control group, there was no significant difference in the morphology and density of RGCs of sham operation group(P>0.05). In 1d, 3d, 7d and 14d after traction of the optic nerve groups, the number of RGCs were reduced progressively and the density of RGCs of the left eye was significantly lower than that in the normal control group(P<0.01). The survival rates of RGCs in the groups of 1d, 3d, 7d and 14d after optic nerve traction were(78.94±0.92)%,(60.07±0.90)%,(38.92±1.42)% and(17.31±0.97)% respectively.

CONCLUSION:The transverse quantitative traction method can establish a model of easily quantifiable optic nerve injury, which can provide a powerful tool for further study on the treatment of optic nerve injury.