视网膜神经节细胞凋亡对延迟整流钾电流的影响  

Effects of retinal ganglion cell apoptosis on delayed rectifier K^+ currents

作　　者：赵瑛[1] 徐亚吉[2] 路雪婧[1] 段俊国[1] 

机构地区：[1]成都中医药大学视觉生理重点实验室,四川成都610075 [2]成都大学生理教研室,四川成都610106

出　　处：《中国病理生理杂志》2016年第8期1403-1407,共5页Chinese Journal of Pathophysiology

基　　金：国家科技部重大新药创制资助项目(No.2009ZX09103-369);四川省教育厅重点项目(No.200ZD013)

摘　　要：目的:观察视网膜神经节细胞(retinal ganglion cells,RGCs)凋亡对延迟整流钾电流(delayed rectifier K^+ currents,I_K)的影响。方法:将原代培养2~3 d的SD乳大鼠RGCs分为对照组、加压0.5 h组、加压1 h组、加压1.5 h组和加压2 h组,对照组为常规培养6 d;其它各组常规培养6 d后用自行设计的加压装置加压80 mmHg,时间分别为0.5 h、1 h、1.5 h和2 h,通过连续波长多功能微孔板检测仪检测各组RGCs线粒体的荧光强度;通过全细胞膜片钳技术观察各组细胞膜电容(membrane capacitance,C_m)的变化,观察对照组与加压1 h组I_K、V_(1/2)、k和G_(max)的变化。结果:对照组RGCs线粒体的荧光强度与加压0.5 h组比较差异无统计学显著性,而加压1 h、1.5 h和2 h各组RGCs线粒体的荧光强度显著低于对照组(P<0.05);对照组RGCs的细胞Cm与加压0.5 h组比较差异无统计学显著性,其余各组RGCs的细胞C_m显著低于对照组(P<0.05)。与对照组比较,加压1 h能使电流幅度显著增加,在刺激电位为-10 m V^60 m V时,加压1 h组的电流密度明显大于对照组(P<0.05)。加压1 h组的G_(max)值明显高于对照组(P<0.05),V_(1/2)显著小于对照组(P<0.01),两组间比较k值的差异无统计学显著性。结论:视网膜神经节细胞凋亡伴有I_K通道电导增加,I_K增大。AIM： To investigate the effects of rat retinal ganglion cell（RGC） apoptosis on delayed rectifier K＋currents（ I_K）. METHODS： The retinas of 2 ~ 3 d newborn Sprague-Dawley rats were dissociated into cell suspension by trypsin digestion. The RGCs were cultured and divided into control group,pressure 0. 5 h group,pressure 1 h group,pressure 1. 5 h group and pressure 2 h group. The cells were cultured regularly for 6 d in control group,and the cells in other groups were cultured regularly for 6 d and gave pressure of 80 mm Hg for 0. 5 h,1 h,1. 5 h and 2 h,respectively.The rhodamine 123 fluorescence from labeled RGC mitochondrion was detected by continuous wavelength multifunctional microplate detection instrument. The membrane capacitance（ C_m） in different groups and I_Kin the pressure 1 h group were recorded from the RGCs by whole-cell patch-clamp technique. RESULTS： No difference of rhodamine 123 fluorescence in the RGC mitochondria between control group and pressure 0. 5 h group was observed. Rhodamine 123 fluorescence in the other 3 groups was significantly lower than that in control group（ P 0. 05）. No difference of the C_m between control group and pressure 0. 5 h group was found,and the C_min the other 3 groups was significantly lower than that in control group（P 0. 05）. The amplitudes of I_Kwere higher than that in control group. At the test potential from- 10 m V to 60 m V,the current density in pressure 1 h group was significantly higher than that in control group（ P 0. 05）. The maximal conduction（ G_max） in pressure 1 h group was significantly higher than that in control group. The voltage for I_Kchannel half-activation（ V_（1 /2）） in pressure 1 h group declined comparison with control group（P 0. 01）,and the k value had no significant difference between the 2 groups. CONCLUSION： Retinal ganglion cell apoptosis accompanies with delayed rectifier K~＋ current enhancement.

关 键 词：延迟整流钾电流 视网膜神经节细胞 加压 细胞凋亡 

分 类 号：R774.6[医药卫生—眼科] R339.14[医药卫生—临床医学]