Rols M P, Teissié J
Centre de Recherche de Biochimie et de Génétique Cellulaires du CNRS, Toulouse, France.
Biophys J. 1990 Nov;58(5):1089-98. doi: 10.1016/S0006-3495(90)82451-6.
Transient membrane permeabilization by application of high electric field intensity pulses on cells (electropermeabilization) depends on several physical parameters associated with the technique (pulse intensity, number, and duration). In the present study, electropermeabilization is studied in terms of flow of diffusing molecules between cells and external medium. Direct quantification of the phenomenon shows that electric field intensity is a critical parameter in the induction of permeabilization. Electric field intensity must be higher than a critical threshold to make the membrane permeable. This critical threshold depends on the cell size. Extent of permeabilization (i.e., the flow rate across the membrane) is then controlled by both pulse number and duration. Increasing electric field intensity above the critical threshold needed for permeabilization results in an increase membrane area able to be permeabilized but not due to an increase in the specific permeability of the field alterated area. The electroinduced permeabilization is transient and disappears progressively after the application of the electric field pulses. Its life time is under the control of the electric field parameters. The rate constant of the annealing phase is shown to be dependent on both pulse duration and number, but is independent of electric field intensity which creates the permeabilization. The phenomenon is described in terms of membrane organization transition between the natural impermeable state and the electro-induced permeable state, phenomenon only locally induced for electric field intensities above a critical threshold and expanding in relation to both pulse number and duration.
通过对细胞施加高电场强度脉冲实现的瞬时膜通透性改变（电通透化）取决于与该技术相关的几个物理参数（脉冲强度、数量和持续时间）。在本研究中，从扩散分子在细胞与外部介质之间的流动角度对电通透化进行了研究。对该现象的直接定量表明，电场强度是诱导通透性改变的关键参数。电场强度必须高于临界阈值才能使膜具有通透性。这个临界阈值取决于细胞大小。然后，通透性改变的程度（即跨膜流速）由脉冲数量和持续时间共同控制。将电场强度提高到通透性改变所需的临界阈值以上，会导致可通透化的膜面积增加，但这并非是由于电场改变区域的比通透性增加所致。电诱导的通透性改变是短暂的，在施加电场脉冲后会逐渐消失。其持续时间受电场参数控制。退火阶段的速率常数显示既取决于脉冲持续时间和数量，又与产生通透性改变的电场强度无关。该现象被描述为膜在自然不可渗透状态和电诱导可渗透状态之间的组织转变，这种现象仅在电场强度高于临界阈值时局部诱导产生，并随着脉冲数量和持续时间的增加而扩展。
