Minimal model for intracellular calcium oscillations and electrical bursting in melanotrope cells of Xenopus Laevis

L. Niels Cornelisse*, Wim J.J.M. Scheenen, Werner J.H. Koopman, Eric W. Roubos, Stan C.A.M. Gielen

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

A minimal model is presented to explain changes in frequency, shape, and amplitude of Ca2+ oscillations in the neuroendocrine melanotrope cell of Xenopus Laevis. It describes the cell as a plasma membrane oscillator with influx of extracellular Ca2+ via voltage-gated Ca2+ channels in the plasma membrane. The Ca2+ oscillations in the Xenopus melanotrope show specific features that cannot be explained by previous models for electrically bursting cells using one set of parameters. The model assumes a KCa-channel with slow Ca2+-dependent gating kinetics that initiates and terminates the bursts. The slow kinetics of this channel cause an activation of the KCa-channel with a phase shift relative to the intracellular Ca2+ concentration. The phase shift, together with the presence of a Na+ channel that has a lower threshold than the Ca2+ channel, generate the characteristic features of the Ca2+ oscillations in the Xenopus melanotrope cell.

Original languageEnglish
Pages (from-to)113-137
Number of pages25
JournalNeural Computation
Volume13
Issue number1
DOIs
Publication statusPublished - 1 Jan 2001
Externally publishedYes

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