Neuroprotective effects of saturated hydrogen water on retinal ganglion cells in rat optic nerve crush model

Objective: To investigate the protective effect of saturated hydrogen water on the retinal ganglion cells (RGC) of the rat optic nerve crush model. Design: Experimental study. Participants: Eighteen healthy adult male SD rats. Methods: Eighteen SD rats were randomly divided into the A, B and C group. There were 6 rats in each group. All the right eyes were selected as the experimental eyes, the left eyes served as controls. And the optic nerve crush model was established by using a micro optic nerve forceps with the clipping pressure of 40 g to crush the exposed optic nerve for 60 s at 2 mm from the optic disc. The rats of group A were given saturated hydrogen water by intraperitoneal injection with a dose of 5 ml/kg/d; those of group B were given saturated hydrogen water by dropping three times a day; and those of group C were given saline by dropping three times a day for consecutive two weeks. At the 9th days after injury, 3% fluorogold injection to both superior colliculus for labeling RGC under anesthesia. At the 14th days after injury, the rats were sacrificed, and RGCs were photographed and counted with mask method. Main Outcome Measures: Survival percentages of RGCs. Results: The average survival percentage of RGCs in A, B and C group was 40.35% ± 13.04%, 58.34% ± 14.00%, and 43.07% ± 7.80%, respectively(F=3.965, P=0.041). A significant difference was found between group B and A(P=0.020), between group B and C (P=0.042). The difference between group A and C was no significant (P=0.698). Conclusion: Dropping saturated hydrogen water into eyes for 14 days may play a protective role for RGCs in rat optic nerve crush model.