Dresden 2006 – wissenschaftliches Programm
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AKB: Biologische Physik
AKB 30: Poster Session I
AKB 30.27: Poster
Montag, 27. März 2006, 15:30–18:00, P1
Microscopic fluctuations determine global behavior of cells — •Alexander Skupin and Martin Falcke — Hahn-Meitner-Institut, Glienicker Str. 100, 14109 Berlin
In the last years, the understanding of the influence and importance of noise in biological systems has substantially increased. Here we show how thermal fluctuations on a microscopic level, i.e. the stochastic manner of ion channels, effect the global behavior of cells. Therfore we present biological experiments which have been done and analyzed in a physical way to characterize the underlying stochastic process and to show the importance of noise. In this context astrocytes are ideal objects of interest. These cells represents the majority of cells in the brain and show spontaneous oscillations of the cytosolic Ca2+ concentration. They are caused by the stochastic opening of ion channels releasing Ca2+ from internal stores into the cytosol. This liberated Ca2+ can activate adjoining channels resulting in a global Ca2+ wave within the cell. We analyzed the periods of these oscillation and the influence of Ca2+ buffer to specify this stochastic mechanism, which seems to be a general one in cells. Due to their coupling to neurons and their role for the genesis of synapses astrocytes might influence the self evolution of the brain in a significant way. Thus, microscopic fluctuations can determine macroscopic biological objects like the brain.