Impulse responses of automaticity in the Purkinje fiber.

Abstract:

:We examined the effects of brief current pulses on the pacemaker oscillations of the Purkinje fiber using the model of McAllister , Noble, and Tsien (1975. J. Physiol. [Lond.]. 251:1-57). This model was used to construct phase-response curves for brief electric stimuli to find "black holes," where rhythmic activity of the Purkinje fiber ceases. In our computer simulation, a brief current stimulus of the right magnitude and timing annihilated oscillations in membrane potential. The model also revealed a sequence of alternating periodic and chaotic regimes as the strength of a steady bias current is varied. We compared the results of our computer simulations with experimental work on Purkinje fibers and pointed out the importance of modeling results of this kind for understanding cardiac arrhythmias.

journal_name

Biophys J

journal_title

Biophysical journal

authors

Chay TR,Lee YS

doi

10.1016/S0006-3495(84)84228-9

subject

Has Abstract

pub_date

1984-04-01 00:00:00

pages

841-9

issue

4

eissn

0006-3495

issn

1542-0086

pii

S0006-3495(84)84228-9

journal_volume

45

pub_type

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