摘要
荧光探针Ｆｌｕｏｒｅｓｃｅｉｎ－ＰＥ在８ｍｍｏｌ／ＬＣａ２＋促进下，能够标记于艾氏腹水癌细胞质膜表面。在不影响膜结构的条件下，利用微量ＴｒｉｔｏｎＸ－１００消除膜表面与介质之间的质子浓度差，通过酸滴定实验，能够得到膜表面ｐＨ与ＦＰＥ荧光强度之间的相关曲线。根据此曲线测定了艾氏腹水癌细胞质膜表面ｐＨ：当介质ｐＨ为７．２时，其膜表面ｐＨ为６．７，其质子浓度大约为介质中的３倍，质子跨膜转运抑制剂ＣＣＣＰ和尼日利亚菌素均能消除膜表面与介质之间的质子浓度差。表明质子跨膜转运确实能够引起艾氏腹水癌细胞质膜表面质子化。
Fluorescein-PE was labelled into the plasma-membrane of Ehrlich ascites cells under the promotion of 8mmol/L Ca2+. Under the condition which did not influence the membrane structure, trace Triton X-100 could eliminate the pH difference between the membrane sarface and the medium. The standard curve of correlation between membrane surface and fluorescence intensity of FPE was obtained by acid titration. The membrane surface pH was measured according to this curve. When the medium pH was 7.2, the plasma membrane surface pH of Ehrlich ascites cells was 6.7 and the proton concentration on the membrane surface was three times as much as that of the medium. CCCP and nigericin which were shown to eliminate proton tanslocation of the plasma-membrane of Ehrlich ascites cells, also dissipate the pH difference existed between the membrane surface and the medium. The results mentioned above showed that the proton translocation can induce plasma-membrane protonation of Ehrlich ascies cells.
出处
《生物物理学报》
CAS
CSCD
北大核心
1995年第2期185-190,共6页
Acta Biophysica Sinica
基金
国家自然科学基金
关键词
膜表面质子化
质子跨膜转运
艾氏腹水癌细胞
Membrane surface protonation Proton translocation Membrane fusion Ehrlich ascites cells
