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PubMed · 10024137

Positive sharp wave and fibrillation potential modeling.

D Dumitru·J C King·W E Rogers·D F Stegeman
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Abstract

A finite muscle fiber simulation program which calculates the extracellular potential for any given intracellular action potential (IAP) was used to model a fibrillation potential and a positive sharp wave. This computer model employs the core conductor model assumptions for an active muscle fiber and allows two distinct types of end effects: a cut or a crush. A "cut end" is defined as a membrane segment with the termination of both active and passive ion channels. The "crush end" is simulated as a focal membrane segment which blocks action potential propagation, and is connected to a region of normal membrane on either side of it so that a normal transmembrane potential is maintained beyond the crush zone. A prototypical positive sharp wave of appropriate amplitude and duration could only be detected extracellularly by using an IAP of the configuration found in denervated rat muscle recorded from a muscle fiber terminating in a crush segment of membrane.

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Action PotentialsAnimalsAxotomyDiaphragmIn Vitro TechniquesModels, BiologicalMuscle ContractionMuscle Fibers, SkeletalNerve CrushRatsSignal Processing, Computer-AssistedJournal Article

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D Dumitru, J C King, W E Rogers, D F Stegeman. 1999. Positive sharp wave and fibrillation potential modeling.. https://doi.org/10.1002/(sici)1097-4598(199902)22%3A2%3C242%3A%3Aaid-mus12%3E3.0.co%3B2-j

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