Lindner P, Neumann E, Rosenheck K
J Membr Biol. 1977 Apr 22;32(3-4):231-54. doi: 10.1007/BF01905221.
Electric field pulses, ranging in intensity from 20 to 50 kV/cm and in duration from 10 to 40 micronsec, caused a transient increase in the membrane permeability of chromaffin granules from the bovine adrenal medulla, that led to partial release of granule soluble constituents. This transient permeability change was long-lived, as compared to the pulse duration, and the main part of material efflux occurred after the termination of the pulse. During the latter phase the temporarily increased permeability decayed to its original value, in the absence of the electric field. This indicated that the structural perturbation induced in the membrane was transient and apparently reversible. The release event was characterized by a field-dependent permeability coefficient ranging from 2x10(-4) cm/sec at 30 kV/cm to 3x10(-3) cm/sec at 50 kV/cm. The resealing process of the membrane could be described by two relaxation times, both of which decreased with increasing field strength. Tau1 varied from about 3.0 msec at 30 kV/cm to less than 2.0 msec at 50 kV/cm, while tau2 varied from about 100 to about 40 msec in the same interval of field strength. The distribution in the degree of filling of granules that had been partially depleted by an electric field pulse indicated that the population could be considered homogeneous with respect to release.
强度在20至50 kV/cm之间、持续时间在10至40微秒之间的电场脉冲，导致来自牛肾上腺髓质的嗜铬颗粒膜通透性出现短暂增加，进而导致颗粒可溶性成分部分释放。与脉冲持续时间相比，这种短暂的通透性变化持续时间较长，且物质外流的主要部分发生在脉冲终止后。在后期阶段，在没有电场的情况下，暂时增加的通透性衰减至其原始值。这表明膜中诱导的结构扰动是短暂的且显然是可逆的。释放事件的特征是场依赖的通透性系数，在30 kV/cm时为2×10⁻⁴ cm/sec，在50 kV/cm时为3×10⁻³ cm/sec。膜的重新封闭过程可以用两个弛豫时间来描述，这两个弛豫时间都随场强增加而减小。τ1在30 kV/cm时约为3.0毫秒，在50 kV/cm时小于2.0毫秒，而τ2在相同场强区间内从约100毫秒变化到约40毫秒。经电场脉冲部分耗尽的颗粒的填充程度分布表明，就释放而言，群体可被视为均匀的。
