Acetylcholine raises excitability by inhibiting the fast transient potassium current in cultured hippocampal neurons.
Acetylcholine raises excitability by inhibiting the fast transient potassium current in cultured hippocampal neurons.
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DOI：
10.1073/pnas.83.9.3022
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发表时间：
1986-05
影响因子：
11.1
通讯作者：
Y. Nakajima;S. Nakajima;R. Leonard;K. Yamaguchi
中科院分区：
文献类型：
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作者：
Y. Nakajima;S. Nakajima;R. Leonard;K. Yamaguchi
用全细胞膜片钳技术研究乙酰胆碱对培养的海马神经元的影响。从幼年大鼠(12-19日龄)的脑片中取出海马区CA1区，在木瓜蛋白酶溶液中孵育，然后分离。将神经元接种在神经胶质饲养层上。实验主要在培养2-6天的神经元上进行。在电压钳下去极化时，这些细胞表现出一种快速瞬时外向电流(A-电流)，该电流可被2.5 mM的4-氨基吡啶抑制。乙酰胆碱(0.1微米)也抑制这一A电流，就像M受体激动剂胆碱和M胆碱一样。不出所料，乙酰胆碱和4-氨基吡啶均能增加动作电位的幅度，延长动作电位的时程。我们的结论是，抑制A电流是乙酰胆碱对海马神经元产生兴奋作用的一种机制。
The effects of acetylcholine on cultured hippocampal neurons were investigated by using the whole-cell version of the patch-clamp technique. The CA1 region of the hippocampus was excised from brain slices of young rats (12-19 day old), incubated in a papain solution, and dissociated. Neurons were plated on a glial feeder layer. The experiments were conducted mostly on neurons cultured for 2-6 days. Upon depolarization under voltage clamp, these cells exhibited a fast transient outward current (A-current), which was inhibited by 4-aminopyridine (2.5 mM). Acetylcholine (0.1 microM) also inhibited this A-current, as did the muscarinic agonists bethanechol and muscarine. As expected from their inhibition of the A-current, acetylcholine and 4-aminopyridine both increased the amplitude of the action potential and prolonged its duration. We conclude that the inhibition of the A-current constitutes a mechanism by which acetylcholine exerts its excitatory influence on hippocampal neurons.