石斛散对人视网膜神经细胞钙离子变化的影响

目的通过观察石斛散对人视网膜神经细胞内钙离子持续升高导致的细胞凋亡的保护作用,探讨其在治疗视网膜变性类疾病方面的作用及机制,为临床治疗同类疾病提供药理学依据。设计实验性研究。研究对象体外培养的人眼视网膜神经细胞。方法利用体外培养的贴壁、伸展以及生长良好人视网膜神经细胞,用Fluo3／AM标记,通过激光共焦扫描显微镜动态观察和记录石斛散和维拉帕米对细胞内钙离子水平以及谷氨酸引起的钙超载的影响。主要指标细胞内钙离子水平(荧光强度)。结果加入谷氨酸后,荧光强度较原基础值增加88％;而石斛散可使荧光强度降低14．8％;维拉帕米降低幅度为57．3％。对先用谷氨酸干预的细胞,石斛散不能降低胞内钙离子水平,但预先用石斛散干预的细胞,谷氨酸升高胞内钙离子30％,与未干预组比较有统计学差异(P=O．000)。结论石斛散具有降低体外培养人视网膜神经细胞内钙离子的作用,同时可以抵抗谷氨酸损伤细胞后引起的胞内钙离子升高,提示其具有抵抗钙超载,抑制视网膜细胞凋亡的作用。

The effect of Shihusan on intracellular free calcium of human retinal neural cells

Objective To explore the effects of Shihusan on the intracellular free calcium of human retina cells and the protection from the damage of glutamate. To investigate its function and mechanism in retinal degeneration diseases, and to offer the basis on which to treat the similar disease clinically. Design Experimental study. Participants Retinal cells from normal human eye. Methods Cultivation of human retinal neural cells was perfonned. The changes of fluorescent density of intracellular free calcium of cultured cells labeled with Fluo3/AM before and after adding Shihusan and verapamil were detected with laser scanning confocal microscopy. In addition, the effect of Shihusan on calcium overload provoked by glutamic acid was observed. Main Outcome Measures The level of intracellular free calcium of retinal cells. Results The retinal cells adhered, spread and grew well in vitro. The fluorescence intensity increased 88% in glutamic acid group, decreased 14.8% and 57.3% in Shihusan group and verapamil group respectively. Shihusan couldn't decrease the intracellular Ca2+ that was increased by glutamic acid, but could inhibit the increasing tendency induced by glutamic acid. The difference was significant compared to control group (P=0.000). Conclusions Shihusan might decrease the level of intracellular free calcium in cultured human retinal cells, and resist the damage of glutamate. Its mechanism was related possibly to resisting calcium overload and inhibiting apoptosis.