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Measuring Fast Calcium Fluxes in Cardiomyocytes
12:10

Measuring Fast Calcium Fluxes in Cardiomyocytes

Published on: November 29, 2011

[Regulation of intracellular calcium signaling in cardiac muscle]

T Tanaka1, R Araki

  • 1Department of Molecular and Cellular Pharmacology, Mie University School of Medicine.

Nihon Rinsho. Japanese Journal of Clinical Medicine
|June 1, 1993
PubMed

Insights

Cardiac drugs alter heart muscle contraction by changing calcium sensitivity. Protein phosphorylation and novel calcium-binding proteins like S100C are key to modulating these effects.

Area of Science:

  • Cardiology
  • Molecular Biology
  • Biochemistry

Context:

  • Cardiac contractile force is regulated by intracellular calcium levels.
  • Various signaling pathways and drugs influence the sensitivity of cardiac contractile proteins to calcium.
  • Understanding these mechanisms is crucial for treating heart conditions.

Purpose:

  • To investigate how different stimuli and drugs modulate the calcium sensitivity of cardiac contractile proteins.
  • To explore the role of protein phosphorylation in regulating myocardial contractility.
  • To identify and characterize novel calcium-binding proteins in the heart.

Summary:

  • Beta-adrenoceptor stimulation decreases calcium sensitivity via cAMP-dependent phosphorylation.
  • Alpha 1-adrenergic agonists, endothelin, and angiotensin II increase calcium sensitivity.
  • Phorbol esters decrease calcium sensitivity through troponin T phosphorylation.
  • Myocardial contractile force can be modulated by drugs affecting calcium affinity of proteins like troponin C and calmodulin.
  • A new calcium-binding protein, S100C, was isolated from porcine heart and its cDNA cloned.

Impact:

  • Provides insights into the molecular mechanisms of cardiac contractility regulation.
  • Identifies potential drug targets for modulating heart function.
  • Highlights the role of protein phosphorylation and calcium-binding proteins in cardiac physiology.
  • Suggests further research into S100C and its role in cardiac signaling.

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