细胞酸化对K562／A02耐药细胞株中P-糖蛋白的影响  

Effect of Intracellular Acidification on P-glycoprotein in Drug-resistant K562/A02 Cells

作　　者：芦颖 李庆华 马丽 李彬 袁文肃 茹永新 王建祥 庞天翔 

机构地区：[1]中国医学科学院、北京协和医学院血液学研究所、血液病医院,实验血液学国家重点实验室,天津300020

出　　处：《中国实验血液学杂志》2009年第3期568-573,共6页Journal of Experimental Hematology

基　　金：国家自然科学基金资助项目(No30570358);天津自然科学基金资助项目(No08JCZDJC19100)

摘　　要：本研究探讨细胞酸化对K562/A02细胞中P-糖蛋白(P-glycoprotein,P-gp)的影响,为抗白血病多药耐药(multidrug resistance,MDR)提供新方法。利用高钾缓冲液对细胞进行酸化,应用激光共聚焦显微镜测定K562及K562/A02细胞内pH值(intracellularp H,pHi);采用MTT法观察细胞酸化对细胞活力的影响;应用流式细胞术检测细胞酸化对K562/A02细胞中P-gp功能的影响;分别采用Western blot及实时定量RT-PCR技术检测P-gp的蛋白表达水平和mRNA表达水平的变化。结果表明:细胞酸化3小时对K562及K562/A02细胞的活力影响较小。在K562/A02细胞中,P-gp的功能随pHi的降低而减弱,细胞酸化明显增加了细胞对罗丹明123(Rhodamine123,Rh123)的累积,并抑制了P-gp介导的Rh123外排。细胞酸化还分别在蛋白水平和mRNA水平抑制了K562/A02细胞中P-gp的表达,并且这种抑制具有pHi及时间的依赖性。结论:细胞酸化能够抑制K562/A02耐药细胞株中P-gp的表达和功能。The aim of this study was to investigate the effect of intracellular acidification on the P-gp in K562/A02 cells. Confocal laser microscope was used to determine the intracellular acidification. MTF assay was used to detect the cytotoxicity of intracellular acidification on K562 and K562/A02 cells. Flow cytometry was applied to measure the influence of intracellular acidification on the activity of P-gp. The P-gp expression at protein and mRNA levels were determined by Western blot and real-time RT-PCR respectively. The results indicated that intracellular acidification had no obvious cytotoxicity on K562 and K562/A02 cells. The function of P-gp in K562/A02 cells weakened along with decrease of intracelhitar acidification, the intracellnlar acidification significantly increased the accumulation of Rhodamine 123 （Rh 123 ） and suppressed the efflux of Rh 123 mediated by P-gp. The intracellular acidification also inhibited the expression of P-gp in K562/A02 cells at protein and mRNA levels which showed intracellular acidification with time- dependence. It is concluded that the intracellular acidification can inhibit the expression and function of P-gp in K562/ A02 cells.

关 键 词：细胞酸化 细胞内PH值 P一糖蛋白 多药耐药 

分 类 号：R733.7[医药卫生—肿瘤]