Zhao Weidong, Cui Wei, Xu Shujun, Cheong Ling-Zhi, Wang Deyu, Shen Cai
Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences 1219 Zhongguan Road Ningbo Zhejiang China
Ningbo Key Laboratory of Behavioral Neuroscience, Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University Ningbo Zhejiang China.
Nanoscale Adv. 2018 Nov 19;1(2):537-545. doi: 10.1039/c8na00202a. eCollection 2019 Feb 12.
Electrical related properties play important roles in biological structures and functions. Herein, the capacitance gradient and local contact potential difference (CPD) of cell bodies and processes of PC12 cells (representative cells of the sympathetic nervous system), hippocampal neurons (representative cells of the central nervous system) and spines were investigated by Electrostatic Force Microscopy (EFM) and Kelvin Probe Force Microscopy (KPFM) at high lateral spatial resolution directly. The results demonstrate that the capacitance gradients of cell bodies, processes and spines of PC12 cells and hippocampal neurons are very close (in the range of 19-23 zF nm) and fit well with the theoretical calculation results (21.7 zF nm). This indicates that the differences of nerve signal activities and functions of the sympathetic and central nervous systems are not related to the electric polarization properties. The CPD of cell bodies and processes of PC12 cells is smaller than that of hippocampal neurons. The CPD of spines is much more negative than that of the cell bodies and processes. These results reveal that the surface potential is closely related to the neural signal transduction functions, and spines play vital roles in neural signal transmission. This work indicates the similarity (capacitance gradient) and differences (surface potential) of the electrical properties between the sympathetic and central nervous systems for the first time. The methods and results of this work are useful in the further study of the electrical properties in cellular activities and physiological processes.
电学相关特性在生物结构和功能中发挥着重要作用。在此，通过静电 force 显微镜（EFM）和开尔文探针力显微镜（KPFM）直接在高横向空间分辨率下研究了 PC12 细胞（交感神经系统的代表性细胞）、海马神经元（中枢神经系统的代表性细胞）及其树突棘的细胞体和突起的电容梯度和局部接触电位差（CPD）。结果表明，PC12 细胞和海马神经元的细胞体、突起和树突棘的电容梯度非常接近（在 19 - 23 zF nm 范围内），并且与理论计算结果（21.7 zF nm）拟合良好。这表明交感神经系统和中枢神经系统的神经信号活动和功能差异与电极化特性无关。PC12 细胞的细胞体和突起的 CPD 小于海马神经元的。树突棘的 CPD 比细胞体和突起的更负得多。这些结果揭示了表面电位与神经信号转导功能密切相关，并且树突棘在神经信号传递中起着至关重要的作用。这项工作首次表明了交感神经系统和中枢神经系统电学特性的相似性（电容梯度）和差异（表面电位）。这项工作的方法和结果有助于进一步研究细胞活动和生理过程中的电学特性。
