Williams Stephen R, Mitchell Simon J
Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK.
Nat Neurosci. 2008 Jul;11(7):790-8. doi: 10.1038/nn.2137. Epub 2008 Jun 15.
The somatic voltage clamp technique has revolutionized understanding of synaptic physiology and the excitability of neurons. Although computer simulations have indicated that the somatic voltage clamp poorly controls voltage in the dendritic tree of neurons, where the majority of synaptic contacts are made, there has not been an experimental description of the performance of the somatic voltage clamp. Here, we directly quantify errors in the measurement of dendritic synaptic input by the somatic voltage clamp using simultaneous whole-cell recordings from the soma and apical dendrite of rat neocortical pyramidal neurons. The somatic voltage clamp did not control voltage at sites other than the soma and distorted measurement of the amplitude, kinetics, slope conductance and reversal potential of synaptic inputs in a dendritic distance-dependent manner. These errors question the use of the somatic voltage clamp as a quantitative tool in dendritic neurons.
体细胞电压钳技术彻底改变了人们对突触生理学和神经元兴奋性的理解。尽管计算机模拟表明，体细胞电压钳对神经元树突棘（大多数突触连接发生的部位）的电压控制不佳，但尚未有关于体细胞电压钳性能的实验描述。在这里，我们通过对大鼠新皮层锥体神经元的胞体和顶端树突进行同步全细胞记录，直接量化了体细胞电压钳测量树突突触输入时的误差。体细胞电压钳除了胞体部位外，无法控制其他部位的电压，并且以树突距离依赖的方式扭曲了突触输入的幅度、动力学、斜率电导和反转电位的测量。这些误差对将体细胞电压钳用作树突神经元的定量工具提出了质疑。
