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Excitation-contraction coupling of the mouse embryonic cardiomyocyte.

ABSTRACT: In the mammalian embryo, the primitive tubular heart starts beating during the first trimester of gestation. These early heartbeats originate from calcium-induced contractions of the developing heart muscle cells. To explain the initiation of this activity, two ideas have been presented. One hypothesis supports the role of spontaneously activated voltage-gated calcium channels, whereas the other emphasizes the role of Ca(2+) release from intracellular stores initiating spontaneous intracellular calcium oscillations. We show with experiments that both of these mechanisms coexist and operate in mouse cardiomyocytes during embryonic days 9-11. Further, we characterize how inositol-3-phosphate receptors regulate the frequency of the sarcoplasmic reticulum calcium oscillations and thus the heartbeats. This study provides a novel view of the regulation of embryonic cardiomyocyte activity, explaining the functional versatility of developing cardiomyocytes and the origin and regulation of the embryonic heartbeat.

SUBMITTER: Rapila R

PROVIDER: S-EPMC2553387 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Excitation-contraction coupling of the mouse embryonic cardiomyocyte.

Rapila Risto R Korhonen Topi T Tavi Pasi P

The Journal of general physiology 20080915 4

In the mammalian embryo, the primitive tubular heart starts beating during the first trimester of gestation. These early heartbeats originate from calcium-induced contractions of the developing heart muscle cells. To explain the initiation of this activity, two ideas have been presented. One hypothesis supports the role of spontaneously activated voltage-gated calcium channels, whereas the other emphasizes the role of Ca(2+) release from intracellular stores initiating spontaneous intracellular ...[more]

PMID: 18794377

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Dataset Information

Excitation-contraction coupling of the mouse embryonic cardiomyocyte.

Publications

Excitation-contraction coupling of the mouse embryonic cardiomyocyte.

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