Abstract
Abstract: :
Purpose:To investigate the neuroprotective effect of Ginexin (Ginkgo biloba extract) on rat retinal ganglion cells in an optic nerve crush injury model. Methods:From one week before the optic nerve injury, Ginexin 100mg/kg/day (100mg group), 200mg/kg/day (200mg group) or the vehicle, carboxymethylcellulose, as a control group (CMC group) was administrated orally for 4 weeks in Spraque-Dawley rats. Three weeks after the optic nerve injury, the retrograde labeling of the retinal ganglion cells (RGCs) was accomplished by dextran tetramethylrhodamine. The labeled RGCs were counted using fluorescence microscopy. The vitreous was separated at the time of enucleation and the intravitreal glutamate concentration was measured. Results:The RGC density of the CMC group (103 ± 22 cells/mm2 , n=10) was significantly lower than that of the 100mg (182 ± 39 cells/mm2, n=10) and the 200 mg group (201 ± 63 cells/mm2, n=7) (p<0.01). The RGC density of the 100mg group and 200mg group was similar. The normal RGC density was 1.185 ± 168/mm2. The invtravitreal glutamate concentration in the normal (792 ± 226 pmol/µl), the CMC group (971 ± 335 pmol/µl;), the 100mg group (884 ± 199 pmol/µl;) and the 200mg group (875 ± 134 pmol/µl) was similar (p>0.05). Conclusions:Ginexin increased the survival of the retinal ganglion cell in the rat optic nerve crush injury model. However, it did not significantly influence the intravitreal glutamate concentration.
Keywords: ganglion cells • neuroprotection • drug toxicity/drug effects