Fear E C, Stuchly M A
Department of Electrical and Computer Engineering, University of Victoria, BC, Canada.
IEEE Trans Biomed Eng. 1998 Oct;45(10):1259-71. doi: 10.1109/10.720204.
Gap junctions are channels through the cell membrane that electrically connect the interiors of neighboring cells. Most cells are connected by gap junctions, and gaps play an important role in local intercellular communication by allowing for the exchange of certain substances between cells. Gap communication has been observed to change when cells are exposed to electromagnetic (EM) fields. In this work, we examine the behavior of cells connected by gap junctions when exposed to electric fields, in order to better understand the influence of the presence of gap junctions on cell behavior. This may provide insights into the interactions between biological cells and weak, low-frequency EM fields. Specifically, we model gaps in greater detail than is usually the case, and use the finite element method (FEM) to solve the resulting geometrically complex cell models. The responses of gap-connected cell configurations to both dc and time harmonic fields are investigated and compared with those of similarly shaped (equivalent) cells. To further assess the influence of the gap junctions, properties such as gap size, shape, and conductivity are varied. Our findings indicate that simple models, such as equivalent cells, are sufficient for describing the behavior of small gap-connected cell configurations exposed to dc electric fields. With larger configurations, some adjustments to the simple models are necessary to account for the presence of the gaps. The gap junctions complicate the frequency behavior of gap-connected cell assemblies. An equivalent cell exhibits low-pass behavior. Gaps effectively add a bandstop filter in series with the low-pass behavior, thus lowering the relaxation frequency. The characteristics of this bandstop filter change with changes to gap properties. Comparison of the FEM results to those obtained with simple models indicates that more complex models are required to represent gap-connected cells.
间隙连接是穿过细胞膜的通道，它将相邻细胞的内部电连接起来。大多数细胞通过间隙连接相连，间隙通过允许细胞间某些物质的交换，在局部细胞间通讯中发挥重要作用。当细胞暴露于电磁场（EM）时，已观察到间隙通讯会发生变化。在这项工作中，我们研究了通过间隙连接相连的细胞在暴露于电场时的行为，以便更好地理解间隙连接的存在对细胞行为的影响。这可能为深入了解生物细胞与微弱、低频电磁场之间的相互作用提供线索。具体而言，我们比通常情况更详细地对间隙进行建模，并使用有限元方法（FEM）来求解由此产生的几何形状复杂的细胞模型。研究了间隙连接的细胞构型对直流和时谐场的响应，并与形状相似（等效）的细胞的响应进行了比较。为了进一步评估间隙连接的影响，改变了间隙大小、形状和电导率等特性。我们的研究结果表明，简单模型，如等效细胞，足以描述暴露于直流电场的小间隙连接细胞构型的行为。对于更大的构型，需要对简单模型进行一些调整，以考虑间隙的存在。间隙连接使间隙连接的细胞集合的频率行为变得复杂。等效细胞表现出低通行为。间隙有效地在低通行为上串联添加了一个带阻滤波器，从而降低了弛豫频率。该带阻滤波器的特性随间隙特性的变化而变化。将有限元方法的结果与简单模型得到的结果进行比较表明，需要更复杂的模型来表示间隙连接的细胞。
