THE IONIC REQUIREMENTS FOR THE PRODUCTION OF ACTION POTENTIALS IN CRUSTACEAN MUSCLE FIBRES
THE IONIC REQUIREMENTS FOR THE PRODUCTION OF ACTION POTENTIALS IN CRUSTACEAN MUSCLE FIBRES
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DOI：
10.1113/jphysiol.1958.sp006034
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发表时间：
1958-01-01
影响因子：
5.5
通讯作者：
GINSBORG, BL
中科院分区：
文献类型：
--
作者：
FATT, P;GINSBORG, BL
用细胞内电极研究了小龙虾四肢肌纤维的电特性。对向外脉冲电流的正常反应是局部电位变化，其中包括早期的振荡成分。膜电阻也出现延迟下降，从而使电位从其初始值的位移减小；这种延迟作用是膜电位由内向电流升高时的正常反应。在含有四乙基铵离子的溶液中长时间浸泡后，某些纤维在去除该物质后可诱发出动作电位。在这些情况下发生的动作电位依赖于钙的存在，而不依赖于钠和镁。本文还研究了不同浓度锶、钡离子溶液中肌纤维的动作电位。结果表明，在锶和钡溶液中出现的动作电位是由于肌纤维膜对这些离子具有高度通透性所致。浴液中锶离子浓度的变化与这一解释是一致的。四乙基铵和其他取代铵化合物的不可逆作用归因于它们对通透性变化机制的作用，延长了钙通过膜所需的时间。
The electrical properties of muscle fibers in limb muscles of the crayfish were studied by means of intracellular electrodes. The normal response to an out-ward pulse of current was a local potential change which included an early oscillatory component. A delayed decrease of membrane resistance also occurred which reduced the displacement of potential from its initial value; this delayed action was the normal response when the membrane potential was raised by an inward current. Following prolonged soaking in a solution containing tetraethylammonium ions, action potentials could be elicited in some fibers after removal of this substance. The action potential occurring in these circumstances depended on the presence of Ca and was independent of Na and Mg. Action potentials of muscle fibers in solutions of varying concentrations of Sr and Ba ions were also studied. It is suggested that the action potential occurring in solutions of Sr and Ba result from the muscle fiber membrane becoming highly permeable to these ions. The effect of variation in the concentration of Sr ions in the bathing solution is consistent with this explanation. The irreversible action of tetraethylammonium and other substituted ammonium compounds is attributed to their having an action on the mechanism of permeability change and prolonging the time required for Ca to cross the membrane.