Haydon D A, Urban B W
J Physiol. 1983 May;338:435-50. doi: 10.1113/jphysiol.1983.sp014682.
The effects of the n-alkanes propane to hexane, cyclopropane, cyclopentane and cyclohexane and carbon tetrachloride on the ionic currents and electrical capacity of the squid giant axon membrane have been examined. Both the peak inward and steady-state outward currents were reduced reversibly by each substance, though propane at 1 atm had very little effect. The membrane capacity at 100 kHz was reduced by all substances except propane at 1 atm. Na currents were recorded in intracellularly perfused axons before and during exposure to the hydrocarbons and the records were fitted with equations similar to those proposed by Hodgkin & Huxley (1952). Shifts in the curves of the steady-state activation and inactivation parameters (m infinity and h infinity) against membrane potential, changes in the peak heights of the activation and inactivation time constants (tau m and tau h) and reductions in the maximum Na conductance (gNa) have been tabulated. The effects of the various hydrocarbons and carbon tetrachloride on the parameters of the Hodgkin-Huxley equations suggest that the suppression of the Na current by these substances originates from several different phenomena. The underlying physico-chemical events are considered in the light of the observed capacity changes and of information on artificial pore-containing membranes.
研究了正构烷烃丙烷至己烷、环丙烷、环戊烷和环己烷以及四氯化碳对乌贼巨大轴突膜离子电流和电容的影响。每种物质都能使内向峰值电流和稳态外向电流可逆性降低，不过1个大气压下的丙烷影响极小。除1个大气压下的丙烷外，所有物质都能降低100kHz时的膜电容。在细胞内灌注轴突暴露于碳氢化合物之前和期间记录钠电流，记录结果用类似于霍奇金和赫胥黎（1952年）提出的方程进行拟合。已将稳态激活和失活参数（m无穷大和h无穷大）相对于膜电位的曲线位移、激活和失活时间常数（τm和τh）峰值高度的变化以及最大钠电导（gNa）的降低制成表格。各种碳氢化合物和四氯化碳对霍奇金-赫胥黎方程参数的影响表明，这些物质对钠电流的抑制源于几种不同的现象。根据观察到的电容变化以及关于含人工孔膜的信息，对潜在的物理化学事件进行了考虑。
