氯离子通道2对压力应激状态下人眼小梁细胞功能的影响

Effect of chloride channel 2 on trabecular meshwork cells under pressure stress condition

目的探讨分布于小梁细胞上的氯离子通道2(ClC-2)与小梁细胞数量及功能之间的关系,以进一步了解原发性开角型青光眼的形成机制。方法首先分别利用反转录聚合酶链反应、台盼蓝染色、末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法检测不同压力,以及不同压力作用时间下小梁细胞ClC-2mRNA表达、小梁细胞活力及凋亡情况的变化;再利用RNAi技术抑制ClC-2mRNA的表达,观察一定压力及作用时间下小梁细胞活力、凋亡情况的变化。结果与0mm Hg(1mm Hg=0.133kPa)、20mm Hg相比,30mmHg及40mm Hg时,随压力作用时间的增加,ClC-2mRNA的表达明显增高,差异有统计学意义;表达最高点为24h;60mm Hg时,各时间点下ClC-2mRNA的表达较30mm Hg、40mm Hg时明显降低,差异有统计学意义,且随时间延长,ClC-2mRNA的表达逐渐下降。当40mm Hg及60mm Hg的压力持续作用一段时间后,小梁细胞活力明显降低,凋亡指数明显增加,差异有统计学意义。抑制ClC-2mRNA表达后,压力应激状态下小梁细胞活力下降及凋亡增加更显著,差异有统计学意义。结论压力应激条件下,ClC-2表达的变化与小梁细胞的活力及凋亡有一定的相关性,提示ClC-2对小梁细胞存在保护作用。

Objective To study the relationship between chloride channel 2 （CIC-2） and the number and func- tion of trabecular meshwork cells （HTC） for further understanding the occurrence and development of primary open angle glaucoma（POAG）. Methods In the first part, reverse transcriptional polymerase chain reaction,Trypan Blue Staining and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling was applied respectively to detect the changes of CIC-2 mRNA expression, viability and apoptosis in HTC pretreated with different pressures and time. The following step was to repeat the above procedures on HTC after its CIC-2 mRNA expression had heen suppressed. Results ThemRNA expression of CIC-2 on HTC significantly increased as the time going under the pressures of 30 mm Hg and 40 mm Hg, compared with 0 mm Hg and 20 mm Hg. There was a top expression when HTC had been treated for 24 h un- der the pressures of 30 mm Hg and 40 mm Hg. There was a statistical difference in CIC-2 mRNA expression between 60 mm Hg and 30 mm Hg and between 60 mm Hg and 40 mm Hg at any time-point. CIC-2 mRNA expression gradually de- clined with the time under the pressure of 60 mm Hg. The viability and apoptosis of HTC had a significant change when the pressure was above 40 mm Hg. Under some pressure stress, the viability and apoptosis of HTC which had been trans- fected with CIC-2 siRNA decreased and increased respectively. Conclusions There was some relationship between mRNA expression of CIC-2 and the viability and the apoptosis of HTC under different introcular pressure for different time. （ Chin J Ophthalmol and Otorhinolaryngo1,2012,12：26-29）