Mechanism of conduction block in amphibian myelinated axon induced by biphasic electrical current at ultra-high frequency.
Summary of "Mechanism of conduction block in amphibian myelinated axon induced by biphasic electrical current at ultra-high frequency."
The mechanism of axonal conduction block induced by ultra-high frequency (â‰¥20Â kHz) biphasic electrical current was investigated using a lumped circuit model of the amphibian myelinated axon based on Frankenhaeuser-Huxley (FH) equations. The ultra-high frequency stimulation produces constant activation of both sodium and potassium channels at the axonal node under the block electrode causing the axonal conduction block. This blocking mechanism is different from the mechanism when the stimulation frequency is between 4Â kHz and 10Â kHz, where only the potassium channel is constantly activated. The minimal stimulation intensity required to induce a conduction block increases as the stimulation frequency increases. The results from this simulation study are useful to guide future animal experiments to reveal the different mechanisms underlying nerve conduction block induced by high-frequency biphasic electrical current.
Department of Urology, University of Pittsburgh, 700 Kaufmann Building, Pittsburgh, PA, 15213, USA, firstname.lastname@example.org.
This article was published in the following journal.
Name: Journal of computational neuroscience
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/21523417
- DOI: http://dx.doi.org/10.1007/s10827-011-0329-9
Medical and Biotech [MESH] Definitions
Impaired conduction of cardiac impulse that can occur anywhere along the conduction pathway, such as between the SINOATRIAL NODE and the right atrium (SA block) or between atria and ventricles (AV block). Heart blocks can be classified by the duration, frequency, or completeness of conduction block. Reversibility depends on the degree of structural or functional defects.
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Impaired impulse conduction from HEART ATRIA to HEART VENTRICLES. AV block can mean delayed or completely blocked impulse conduction.
Nerve Fibers, Myelinated
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