影响心肌细胞所受电场应力和膜内电能的因素  

Factors affecting electric field stress on cardiomyocyte and electrical energy stored in cell membrane

作　　者：张辉[1] 张小娣[1] ZHANG Hui;ZHANG Xiaodi(College of Physics and Electronic Engineering,Xianyang Normal University,Xianyang 712000,China)

机构地区：[1]咸阳师范学院物理与电子工程学院,陕西咸阳712000

出　　处：《中国医学物理学杂志》2022年第2期252-256,共5页Chinese Journal of Medical Physics

基　　金：国家教育部产学协同育人项目(201901260024);陕西省科技厅科研基金(2019KRM026)。

摘　　要：目的:研究影响心肌细胞所受电场应力及细胞膜内储存电能改变的因素。方法:通过求解边值问题,得到细胞内外区域电势分布,并应用生物电磁学理论、电场应力张量法分析影响细胞膜内储存电能以及心肌细胞应力分布因素。结果:细胞半径越大,作用在细胞上的拉力与压力交界点对应极角越大,电场法向、切向应力随胞外介质介电常数变化率越大。在细胞半径较小范围内,电场引起的应力和膜内储存的电能随半径增加变化较大;否则,应力和电能随半径变化较小。结论:心肌细胞直径、胞外介质的介电常数均影响细胞所受的电场应力和细胞膜内储存的电能;半径较小的细胞,外加直流电场的影响更为明显;直流电场可引起细胞的形变、融合、旋转、离子跨膜迁移量的改变,产生细胞生物学效应。Objective To explore the factors affecting the electric field stress on myocardial cells and the electrical energy stored in the cell membrane.Methods By solving the boundary value problem,the potential distributions inside and outside the cells were obtained,and the factors affecting the energy stored in the cell membrane and the electric field stress distribution on cardiomyocyte were analyzed by the theory of bio-electromagnetics and the electric field stress tensor method.Results With larger cell radius,the polar angle corresponding to the junction point of the pulling force and pressure acting on the cell was larger,and the change rates of the electric field normal and tangential stresses with the dielectric constant of the extracellular medium were also larger.The stress caused by the electric field and the electric energy stored in the cell membrane changed obviously within a small cell radius;otherwise,the stress and the change rate changed little with cell radius.Conclusion Both the radius of cardiomyocyte and the dielectric constant of extracellular medium affect the electric field stress and the electric energy stored in the cell membrane,and the cells with smaller radius are more easily affected by the additional direct-current electric field.Direct-current electric field can lead to cell deformation,fusion,rotation,and the changes of the ion trans-membrane migration,thereby resulting in cell biological effects.

关 键 词：心肌细胞 电场应力 膜内电能 介电常数 

分 类 号：R318[医药卫生—生物医学工程]