Influence of nanomaterial on cardiac function
Leader: Andreas Stampfl
Background
Nanomaterials are defined as particles which have at least 2 dimensions smaller than 100 nm, for example nanotubes with a diameter smaller than 100nm. Particles smaller than 100 nm are called ultrafine particles (UFP). Chemically they are elements, anorganic compounds, organic compounds or composites. Epidemiological studies show a correlation between elevated concentrations of UFP in the ambient air and heart dysfunctions. It is already known that UFP are deposited partially in the lung. A small amount of the particles is translocated into the bloodstream and to the organs.
Methods
The epidemiological findings are experimentally verified. This is done in a common project of the HelmholtzZentrum Munich and the EPA (USA). To study the direct effect of UFP on the heart in vitro a so called Langendorff heart was modified. From the isolated heart of a rodent the ECG was recorded. The impact of UFP on the heart can be studied by analyzing the ECG.
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Isolated heart of a rodent with ECG electrodes | Comparison of electrocardiograms (ECG)Upper panel: ECG of living animalMiddle panel: ECG of the isolated heart of the same animalLower panel: human ECG |
- Cardiac cell Transmission picture; Contracting cell calcium concentration in pseudo color
In another approach we investigate the influence of UFP on the calcium regulation in isolated cardiac myocytes using fast live cell fluorescence imaging. The cells are loaded with the calcium sensitive fluorescence dye Fura 2 and electrically stimulated. Morphological changes were observed using transmission pictures and the free intracellular calcium concentration is measured by a fast fluorescence microscopy also during the contraction. Furthermore is it possible to register simultaneously the shortening of the cell with the same method.