Ca2+-activated K+ channels in erythrocytes and excitable cells.
Ca2+-activated K+ channels in erythrocytes and excitable cells.
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红细胞和可兴奋细胞中的 Ca2 激活 K 通道。
DOI：
10.1146/annurev.ph.45.030183.002043
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发表时间：
1983
影响因子：
18.2
通讯作者：
H. Passow
中科院分区：
文献类型：
--
作者：
W. Schwarz;H. Passow
许多生理功能的正常执行，如神经和肌肉冲动的恢复，心脏和神经元起搏器的活动，光的接收，分泌和受精，通常需要精确定时和选择性的K+渗透性变化。这些变化是由不同通道的激活引起的，这些通道可分为两类：由膜电位变化激活的通道，以及由Ca 2+激活并由膜电位调节的通道（5，9，22，29，37，47，70，84 a）。在神经轴突中，仅发现了电位激活的K+通道（66）。然而，在神经元的索马和迄今为止研究的大多数其他类型的细胞中，发现了单独或与潜在的钙激活通道一起的钙激活通道。其他细胞甚至包括不可兴奋的细胞，如巨噬细胞、L细胞和红细胞。本文仅对钙激活的钾离子选择性通道进行综述（表I）。Ca 2+激活的K+选择性通道首先在红细胞中发现，其功能似乎在任何程度上不依赖于K+渗透性的变化或相关的膜电位变化。Wilbrandt（99）在20世纪30年代后期进行的研究表明，葡萄糖分解抑制剂氟化物和碘乙酸盐可以诱导K+ emux的选择性增加，超过了K-Na泵能量供应中断后预期的增加。Gw-dos（26）证实并扩展了这些观察结果，他表明代谢抑制必须伴随着Ca 2+的存在才能获得响应。后来的研究表明，某些药物的存在[如普萘洛尔（19，83）]使细胞对
The proper execution of many physiological functions, such as the conduc tion of impulses in nerve and muscle, the activities of cardiac and neuronal _.pacemakers, light reception, secretion, and fertilization, usually requires accurately timed and selective changes of K+ permeability. These changes are brought about by the activation of distinct channels that can be divided into two classes: those activated by variations in the membrane potential, and others activated by Ca2+ (5,9,22,29,37,47,70, 84a) and modulated by the membrane potential. In nerve axons, only the potential-activated K+ channels have been found (66). However, in the soma of neurons and in most other types of cells that have been studied so far, Ca2+-activated channels were discovered, either alone or together with the potential activated channels. The other cells include even nonexcitable cells such as macrophages, L-cells, and erythrocytes. Only the Ca2+-activated K+-selec tive channels form the subject of the present review (Table I). Ca2+-activated, K+-selective channels were first discovered in red cells, whose functions do not seem to depend to any extent on variations of K+ permeability or the associated variations of membrane potential. Ob servations made by Wilbrandt (99) in the late 1930s showed that the glucolytic inhibitors fluoride and iodoacetate could induce a selective increase of K+ emux that exceeded the increment expected to occur after an interruption of the energy supply to the K-Na pump. These observa tions were confirmed and extended by Gw-dos (26), who showed that the inhibition of metabolism must be accompanied by the presence of Ca2+ to obtain the response. Later work has shown that the presence of cer tain drugs [e.g. propranolol (19, 83)] renders the cells sensitive to