caa a22 4500 465783554 CHVBK 20180323112002.0 cr unu---uuuuu 170327e19900701xx s 000 0 eng 10.1007/BF02446148 doi (NATIONALLICENCE)springer-10.1007/BF02446148 Plonsey R. Department of Biomedical Engineering, Cell Biology, Duke University, 27706, Durham, NC, USA aut Effect of intracellular anisotropy on electrical source determination in a muscle fibre [Elektronische Daten] [R. Plonsey] Expressions are available for describing, quantitatively, the source associated with an action potential propagating along an excitatble fibre. For a nerve fibre one such expression defines an equivalent volume dipole density function τ(x) = − ∂/∂x (σi φi(x) − σe φe(x))ax (where x is the axial co-ordinate, i is the intracellular and e the extracellular region, σi and σe are isotropic conductivities, ϕ the potential at the membrane, while axial symmetry is assumed), and this source fills the intracellular region. This source, as distinct from transmembrane current formulations, lies in a uniform, isotropic, extracellular, medium. Consequently, for a fibre bundle a simple superposition of sources, all lying in a uniform, isotropic, extracellular space, can be accomplished. However, for muscle fibres the presence of non-conducting myofibrils causes the intracellular space to be anisotropic. The paper describes the modification in the aforementioned expressions for the case of longitudinal and transverse propagation and extrapolation to an arbitrary angle of propagation. The resultant source continues to be expressed relative to a uniform, isotropic, extracellular medium. IFMBE, 1990 Action potentials nationallicence Anisotropic nationallicence Electrical source nationallicence Muscle fibres nationallicence Myofibrils nationallicence Medical and Biological Engineering and Computing Kluwer Academic Publishers 28/4(1990-07-01), 312-316 0140-0118 28:4<312 1990 28 11517 https://doi.org/10.1007/BF02446148 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02446148 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Plonsey R. Department of Biomedical Engineering, Cell Biology, Duke University, 27706, Durham, NC, USA aut NATIONALLICENCE 773 0- Medical and Biological Engineering and Computing Kluwer Academic Publishers 28/4(1990-07-01), 312-316 0140-0118 28:4<312 1990 28 11517 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer