Zegarra-Moran O, Porcelli A M, Rugolo M
Lab. di Genetica Molecolare, Genova, Italy.
Biochim Biophys Acta. 2001 Feb 14;1535(2):120-7. doi: 10.1016/s0925-4439(00)00089-2.
In mouse mammary epithelial C127 cells expressing wild-type cystic fibrosis transmembrane conductance regulator (CFTR), chloride efflux, measured with the Cl(-)-sensitive dye 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ), was stimulated by activation of protein kinase A with cyclic AMP elevating agents forskolin plus 3-isobutyl-1-methyl-xanthine (IBMX) and, to a less extent, by activation of protein kinase C with the phorbol 12-myristate 13-acetate (PMA). Conversely, bicarbonate influx, determined by intracellular alkalinization of cells incubated with the pH-sensitive dye 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluoresceintetraacetoxymethyl ester (BCECF-AM), was stimulated by cyclic AMP elevation, but not by PMA. Patch clamp analysis revealed that PMA activated a Cl(-) current with the typical biophysical characteristics of swelling-activated current and not of CFTR.
在表达野生型囊性纤维化跨膜传导调节因子（CFTR）的小鼠乳腺上皮C127细胞中，用氯离子敏感染料6-甲氧基-N-（3-磺丙基）喹啉鎓（SPQ）测量的氯离子外流，可通过用环磷酸腺苷升高剂福斯可林加3-异丁基-1-甲基黄嘌呤（IBMX）激活蛋白激酶A来刺激，并且在较小程度上可通过用佛波酯12-肉豆蔻酸酯13-乙酸酯（PMA）激活蛋白激酶C来刺激。相反，用pH敏感染料2'，7'-双（2-羧乙基）-5（6）-羧基荧光素四乙酰氧基甲基酯（BCECF-AM）孵育细胞后的细胞内碱化所测定的碳酸氢根内流，可通过环磷酸腺苷升高来刺激，但不能通过PMA来刺激。膜片钳分析显示，PMA激活了一种具有肿胀激活电流而非CFTR典型生物物理特性的氯离子电流。
