Mersel M, Malviya A N, Hindelang C, Mandel P
Biochim Biophys Acta. 1984 Nov 21;778(1):144-54. doi: 10.1016/0005-2736(84)90458-9.
Rat astrocytes in primary cultures were employed to isolate the plasma membrane. The method for the isolation of plasma membrane was based on the capacity of the cytoskeleton to adhere to the substratum entrapping intracellular organelles during freezing-thawing cycle performed on the cell. By washing the 'surface adherent framework', the untrapped plasma membrane were recovered and density equilibrium centrifugation resulted in the isolated membrane. The isolated plasma membrane was characterized on the basis of a variety of marker enzymes positive to the plasma membrane such as (Na+ + K+)-ATPase or 5'-nucleotidase as well as the lack of conventional markers of other endomembranes. Ultrastructurally the membranes, as isolated here, were mainly vesicular in nature. The isolated plasma membrane was devoid of the dehydrogenase responsible for NADH-cytochrome c reductase activity. However, NADH-ferricyanide reductase activity and the dehydrogenase system catalyzing the transfer of reducing equivalents from NADH or NADPH to dichloroindophenol seems plasma membrane redox system. The identical specific activity employing dichloroindophenol as an electron acceptor with NADH or NADPH as donor indicate a DT-diaphorase (EC 1.6.99.2) like activity in the astrocytes plasma membrane.
原代培养的大鼠星形胶质细胞被用于分离质膜。质膜分离方法基于细胞骨架在细胞冻融循环过程中黏附于包埋细胞内细胞器的基质的能力。通过洗涤“表面黏附框架”，回收未被包埋的质膜，经密度平衡离心得到分离的膜。分离的质膜通过多种对质膜呈阳性反应的标记酶如（Na+ + K+）-ATP酶或5'-核苷酸酶以及缺乏其他内膜的传统标记物来表征。从超微结构来看，此处分离得到的膜本质上主要是囊泡状。分离的质膜缺乏负责NADH-细胞色素c还原酶活性的脱氢酶。然而，NADH-铁氰化物还原酶活性以及催化还原当量从NADH或NADPH转移至二氯靛酚的脱氢酶系统似乎是质膜氧化还原系统。以二氯靛酚作为电子受体、NADH或NADPH作为供体时相同的比活性表明星形胶质细胞质膜中存在类似DT-黄递酶（EC 1.6.99.2）的活性。
