Szabo G, Rédai I, Bacso Z, Hevessy J, Damjanovich S
Department of Biophysics, Medical University School of Debrecen, Hungary.
Biochim Biophys Acta. 1989 Mar 13;979(3):365-70. doi: 10.1016/0005-2736(89)90258-7.
Merocyanine 540 (M540) is a potential-sensitive, hydrophobic dye that preferentially incorporates into the 'fluid' domains of cellular membranes, distinguishing between hemopoietic cells according to their differentiation state. A bright staining with M540 is usually achieved by UV illumination of the cells during staining. We show by flow cytometric analysis that: (1) staining is greatly enhanced by UV illumination of mouse spleen cells before addition of the dye; (2) UV treatment causes an increased permeability toward propidium iodide and intracellular fluorescein as well; (3) the increment in M540 fluorescence precedes permeabilization to propidium iodide, while the latter precedes leakage of fluorescein. We also describe an overshoot and accelerated recovery of M540 fluorescence after photobleaching by a 514 nm laser beam. It is suggested that penetration of M540 to the more fluid inner membrane structures explains the fluorescence increment in both experiments.
部花青540（M540）是一种对电位敏感的疏水性染料，它优先掺入细胞膜的“流体”结构域，根据造血细胞的分化状态对其进行区分。在染色过程中，通常通过紫外线照射细胞来实现用M540进行明亮染色。我们通过流式细胞术分析表明：（1）在添加染料之前，对小鼠脾细胞进行紫外线照射可大大增强染色效果；（2）紫外线处理还会导致细胞对碘化丙啶和细胞内荧光素的通透性增加；（3）M540荧光的增加先于碘化丙啶的通透，而碘化丙啶的通透先于荧光素的泄漏。我们还描述了用514nm激光束进行光漂白后，M540荧光的过冲和加速恢复。有人认为，M540渗透到流动性更强的内膜结构中解释了这两个实验中的荧光增加现象。
