The morphology of single muscle fibre potentials - part I: simulation study of the distortion introduced by the distant-interfering potentials

Some morphologic aspects of human single fibre action potentials (SFAPs) are not sufficiently well-known. This uncertainty especially concerns the declining negative phase and the final positive phase (third phase) of SFAPs, as these parts are significantly affected by distant electrical activity. T...

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Detalles Bibliográficos
Autores: Rodríguez Falces, Javier, Gila Useros, Luis, Dimitrova, Nonna Alexandrovna
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2013
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/55592
Acceso en línea:https://hdl.handle.net/2454/55592
Access Level:acceso abierto
Palabra clave:Single fibre action potential
SFAP morphology
SFAP third phase
Intracellular action potential
IAP spike duration
Descripción
Sumario:Some morphologic aspects of human single fibre action potentials (SFAPs) are not sufficiently well-known. This uncertainty especially concerns the declining negative phase and the final positive phase (third phase) of SFAPs, as these parts are significantly affected by distant electrical activity. The incomplete characterisation of the SFAP shape is also explained by the limited knowledge of human intracellular action potentials (IAPs). The objectives of this study are to assess the morphologic features of human SFAPs and to derive information about the characteristics of human IAPs. To achieve this, the study has been divided into two parts. The present paper, Part I, aims to analyse the changes in the SFAP time-course introduced by distant-interfering potentials and to evaluate how these changes depend on the spike duration of the corresponding IAP. It was found that, for fibre-to-electrode distances shorter than about 0.2 mm, SFAPs generated by short-spike IAPs have a declining negative phase with a steep approximately constant slope that is largely unaffected by the potentials from distant fibres. For the same distances, SFAPs resulting from wide-spike IAPs have a declining negative phase with a slow return towards the baseline that is highly sensitive to distant-interfering potentials. The third phase of an SFAP is considerably distorted by distant potentials irrespective of the spike duration of the IAP.