ABSTRACT
Background Glaucoma is the second leading cause of blindness,which is characterized by processing retinal ganglion cells (RGCs) loss and optic nerve dystrophy.Clinical study showed that lowing IOP can not arrest the glaucomatous damage of RGCs.To seek a neuroprotective drug is an urgent need.Objective This present study focused on the effect of triptolide,a natural biologically active compound extracted from Tripterygium wilfordii,on RGCs in glaucomatous eyes. Methods Glaucoma animal models were established in the right eyes of 80 clean Wistar rats by combination with aspiration of aqueous humor and phtocoagulation on anterior chamber angle.Wistar rats were assigned to two groups at random.Triptolide (5μg/kg) was intraperitoneally injected daily from three days before photocoagulation through scarification of animals (total 8 weeks),and same amount of physiologic saline solution was used at the same way.IOP was measured with a Tonopen XL tonometer at at 1day,3,5,7 days and weekly for 8-week duration after phtocoagulation.RGCs numbers was calculated by retinal Nissl staining.Morphology of retina in frozen section was examined under the light microscope.The experiment followed the Standard of Association for Research in Vision and Ophthalmology. Results The IOP was elevated in model eyes from 1 day through 3 weeks after operation with statistically different in comparison with before operation(P0.05).The numbers of RGCs of model eyes in normal saline group decreased gradually after operation,but no evident decline of numbers of RGCs in model eyes in triptolide group. RGCs in triptolide group were considerably more than those of normal saline group in various time points after operation ( P<0. 05). However,no obvious difference in RGCs numbers was found between model eyes and control eyes in Triptolide group. Conclusion Triptolide could protect RGCs in glaucomatous eyes,and its effect does not depend on IOP in chronic glaucoma model.