Abstract: Objective To observe the change of retinal ganglion cells(RGCs)and the expression of Bad after optic nerve injury, so as to study the changes of optic function level on morphology and molecular. Methods The experimental models of optic nerve crush were established in fifty Wistar rats. At the different time after injuries (from one to twenty-eight day), the changes of RGCs were observed under microscope. Immunohistochemiscal technique and computer image analysis methods were performed to observe the changes of Bad in RGCs in rats. Results The number of RGCs was reduced significantly according to partial lesion of optic nerve crush. An initial loss of RGCs densities was accelerated in one week after nerve crush, two weeks later the trend mitigated. After four weeks, no obvious change were observed. The expression of Bad increased in 3 days, reached peak in 5 days, and declined one week later. No obvious changes were observed after two weeks. Conclusion The expression of Bad lead to the loss of RGCs following optic nerve crush. This is the important reason of loss optic function. The identification on optic nerve injuries should be done at least four weeks later.

Key words: optic nerve crush, retinal ganglion cells(RGCs), Bad, visual function