川芎嗪对慢性高眼压大鼠视网膜神经节细胞凋亡的影响

Effects of tetramethylpyrazine on retinal ganglion cells apoptosis induced by chronic elevated intraocular pressure in rats

目的研究川芎嗪对慢性高眼压大鼠视网膜神经节细胞(retina ganglion cells,RGC)凋亡的保护作用。方法健康SD大鼠30只,随机分为正常组、高眼压组和川芎嗪治疗组,每组10只。高眼压组和治疗组分别采用上巩膜静脉烧灼法制作高眼压模型,正常对照组不做处理。造模成功后7d治疗组给予川芎嗪腹腔注射,正常组与高眼压组给予等量的生理盐水腹腔注射。造模3周后取三组大鼠眼球,行视网膜HE染色、TUNEL原位细胞凋亡检测和Bcl-2免疫组织化学检测。结果造模后高眼压组、川芎嗪治疗组各时间点眼压与正常组比较,差异均有统计学意义(均为P<0.05),而两组间各时间点比较,差异均无统计学意义(均为P>0.05)。正常组、高眼压组、川芎嗪治疗组大鼠视网膜RGC层TUNEL阳性细胞数分别为0、9.00±0.89、3.50±1.89,三组间差异有统计学意义(F=86.160,P=0.000);三组间两两比较,差异均有统计学意义(均为P=0.000)。三组大鼠RGC层Bcl-2阳性表达光密度值分别为0.373±0.090、0.375±0.146、0.390±0.268,三组差异有统计学意义(F=84.658,P=0.000);三间组两两比较,差异均有显著统计学意义(均为P=0.000)。结论川芎嗪通过上调Bcl-2蛋白的表达可明显抑制慢性高眼压大鼠RGC凋亡,从而发挥RGC保护作用。

Objective To observe the protective effects of tetramethylpyrazine （TMP） on retinal ganglion cells（RGC） apoptosis induced by chronic elevated intraocu- lar pressure （IOP） in rats. Methods Thirty Sprague Dawley rats were randomly and evenly divided into three groups （ control group, elevated IOP group, treatment group）. The ocular hypertention rat model was made by cauterizating the episcleral veins. Ele- vated IOP group and treatment group were treated with obstructing three episcleral veins. Control group never got any treatment. TMP was given to the treatment group by intraperitoneal injections after IOP elevated continuously for 7 days, while the elevated IOP group and control group were given to physiological saline of the same quantity by intraperitoneal injections. The rat eyes were made into eyeball samples after being mod- eled for 3 weeks. They were stained with hematoxylin and eosin. The apoptosis of gan- glion cell layer was inspected by TUNEL staining. The Bcl-2 expression was inspected by immunohistochemlstry. Results The IOP of elevated IOP group and treatment group were significantly different from that of control group at different time points（ all P 〈 0.05 ）, while differences of elevated IOP group and treatment group were not signifi- cant（ all P 〉 0.05 ）. The counts of TUNEL-positive cells in control group （0）, the elevat- ed IOP group（9. 00 ±0.89） ,and treatment group（3.50 ± 1.89） were significantly differ- ent（F = 85. 150,P = 0. 000）. Density values of Bcl-2 positive expression in RGC layer （0. 373 ± 0.090,0. 375 ± 0. 145,0. 390 ±0. 258, respectively） were significantly different （F = 85. 150 ,P = 0.000）. The proteinum level in elevated IOP group was significantly dif- ferent from that in control group （P = 0.000）. Conclusion TMP may inhibit the apop- tosis of RGC in chronic elevated IOP by upregrulating the expression of Bcl-2, and play the protective role in RGC.