金丝桃素对视神经损伤大鼠视网膜节细胞的保护作用

Protective effect of hypericin on retinal ganglion cells in rats after the optic nerve was crushed

目的观察金丝桃素对视神经损伤大鼠视网膜节细胞的保护作用。方法24只SD大鼠随机分为正常对照组、单纯夹伤组、生理盐水对照组、金丝桃素治疗组4组，每组6只（12眼）。对所有大鼠行双上丘注射2％荧光金逆行标记节细胞，7d后，对单纯夹伤组、生理盐水对照组、金丝桃素治疗组进行球后视神经钳夹．同时在生理盐水对照组、金丝桃素治疗组玻璃体内分别注入生理盐水和金丝桃素5ul，14d后进行视网膜节细胞的计数。采用SPSS13．0统计软件对所得数据进行t检验。结果视神经夹伤后14d，存活的视网膜节细胞显著减少。单纯夹伤组节细胞存活率为50％，生理盐水对照组节细胞存活率为52％，金丝桃素治疗组节细胞存活率为68％。金丝桃素治疗组相比单纯夹伤组和生理盐水对照组，存活的节细胞明显要多（P〈0．05）。结论玻璃体内注射金丝桃素能减少大鼠视神经损伤后视网膜神经节细胞的死亡率．对视网膜节细胞有保护作用。

Objective To investigate the neuroprotective effect of hypericin on retinal ganglion cells （RGCs） in a rat optic nerve crush model. Methods Eighteen rats underwent bilateral optic nerve crush. These rats were divided into an untreated group, a saline-treated group, and a hypericin-treated group with 6 rats （12 eyes） in each group. Six normal rats acted as controls. 2 % fluorogold （FG） was injected into both sides of the superior colliculus to label RGCs retrogradely. The optic nerves were crushed 7 days after labeling. Rats bad either no additional treatment or the vitreous cavity was injected with either saline or 5 ul of hypericin. RGCs were counted 14 days later. Results The densities of RGCs decreased sharply 14 days after injury. The survival rate of RGCs in the optic nerve crush groups was 50%, 52% and 68% for the untreated, saline and hypericin-treated groups, respectively. The number of RGCs in the saline-treated group and optic nerve crush group was lower than that in hypericin-treated group. Conclusion Intravitreal injection of hypericin can protect the retinal ganglion cells in a rat optic nerve crush model.