López-Vancell R, Beaty G, Stefani E, Rodríguez-Boulan E E, Cereijido M
J Membr Biol. 1984;81(3):171-80. doi: 10.1007/BF01868711.
MDCK cells (epithelioid line derived from the kidney of a normal dog) form monolayers which retain the properties of transporting epithelia. In these cells viruses bud asymmetrically: influenza from the apical, and vesicular stomatitis (VSV from the basolateral membrane (E. Rodríguez-Boulán and D.D. Sabatini, Proc. Natl. Acad. Sci. USA 75: 5071-5075, 1978; E. Rodríguez-Boulán and M. Pendergast, Cell 20: 45-54, 1980). In the present study, we analyzed whether these viruses affect specific ion-translocating mechanisms located in the plasma membrane. We studied the effect of infection on membrane and transepithelial conductance, passive and active unidirectional fluxes of Na+ and K+, intracellular potentials, cellular content of Na+ and K+, and formation of blisters which, in these preparations, are due to the vectorial transport of fluid. Two main observations are derived from these studies. First, infection with VSV caused an increase in transepithelial electrical conductance, due to the opening of tight junctions, 5 to 6 hr after the start of infection, coincident with the accumulation of envelope protein in the cell surface and with the rise in the curve of virus budding. Infection with influenza, on the other hand, increased the transepithelial conductance only late in the infection (12 to 14 hr) when virus production has already stopped. Second, viruses did affect membrane permeability. Yet, the changes observed may not be ascribed to a perturbation of the specific translocating mechanisms for Na+ and K+ which operate in the same region of the plasma membrane that the viruses use to penetrate and leave MDCK cells. The methods used in the present study are not suitable to decide whether the nonspecific changes in permeability elicited by the viruses occur over the whole cell membrane or are restricted to a given region.
MDCK细胞（源自正常犬肾脏的上皮样细胞系）形成的单层细胞保留了转运上皮细胞的特性。在这些细胞中，病毒以不对称方式出芽：流感病毒从顶端出芽，水泡性口炎病毒（VSV）从基底外侧膜出芽（E. Rodríguez-Boulán和D.D. Sabatini，《美国国家科学院院刊》75: 5071 - 5075，1978；E. Rodríguez-Boulán和M. Pendergast，《细胞》20: 45 - 54，1980）。在本研究中，我们分析了这些病毒是否影响位于质膜上的特定离子转运机制。我们研究了感染对膜和跨上皮电导、Na⁺和K⁺的被动和主动单向通量、细胞内电位、细胞内Na⁺和K⁺含量以及水泡形成的影响，在这些制剂中，水泡形成是由于液体的向量运输所致。这些研究得出了两个主要观察结果。首先，感染VSV会导致跨上皮电导增加，这是由于在感染开始后5至6小时紧密连接打开，这与包膜蛋白在细胞表面的积累以及病毒出芽曲线的上升同时发生。另一方面，感染流感病毒仅在感染后期（12至14小时）病毒产生已经停止时才会增加跨上皮电导。其次，病毒确实影响膜通透性。然而，观察到的变化可能不能归因于在病毒用于穿透和离开MDCK细胞的质膜相同区域中起作用的Na⁺和K⁺特定转运机制的扰动。本研究中使用的方法不适合确定病毒引起的通透性非特异性变化是发生在整个细胞膜上还是仅限于特定区域。
