Ogden D C, Gray P T, Colquhoun D, Rang H P
Pflugers Arch. 1984 Jan;400(1):44-50. doi: 10.1007/BF00670535.
The acetylcholine activated conductance of chick ciliary ganglion neurones grown in tissue culture was studied by the patch clamp method. Single channel currents at 30 degrees C had a conductance of 38-42 pS, a reversal potential near + 10 mV and an average open lifetime of 1.08 ms (range 0.74 - 1.54 ms) at the resting potential. The presence of a single component in the distributions of amplitudes and open lifetimes, and also in the noise spectrum of voltage clamp currents, suggests that acetylcholine channels have uniform characteristics in these cells. Evidence of a desensitised state of the receptor was obtained from the distribution of gap intervals and the decline of voltage clamp current. These properties are similar to those of acetylcholine channels at the vertebrate neuromuscular junction. However, two important differences were found. (a) The acetylcholine concentrations used here were 10-25 times higher than those required to produce a similar degree of channel activation at the endplate. (b) When the membrane was hyperpolarised the mean open lifetime of the channel showed no change or a slight reduction.
采用膜片钳技术研究了在组织培养中生长的鸡睫状神经节神经元的乙酰胆碱激活电导。在30℃时，单通道电流的电导为38 - 42 pS，反转电位接近 +10 mV，在静息电位时平均开放寿命为1.08 ms（范围0.74 - 1.54 ms）。幅度和开放寿命分布以及电压钳电流噪声谱中单一成分的存在表明，乙酰胆碱通道在这些细胞中具有统一的特性。从间隙间隔分布和电压钳电流下降中获得了受体脱敏状态的证据。这些特性与脊椎动物神经肌肉接头处的乙酰胆碱通道相似。然而，发现了两个重要差异。(a) 这里使用的乙酰胆碱浓度比在终板产生类似程度通道激活所需的浓度高10 - 25倍。(b) 当膜超极化时，通道的平均开放寿命没有变化或略有降低。
