20.500.12556/DKUM-35707 Establishing the stochastic nature of intracellular calcium oscillations from experimental data Calcium has been established as a key messenger in both intra- and intercellular signaling. Experimentally observed intracellular calcium responses to different agonists show a variety of behaviors from simple spiking to complex oscillatory regimes. Here we study typical experimental traces of calcium oscillations in hepatocytes obtained in response to phenylephrine and ATP. The traces were analyzed with methods of nonlinear time series analysis in order to determine the stochastic/deterministic nature of the intracellular calcium oscillations. Despite the fact that the oscillations appear, visually, to be deterministic yet perturbed by noise, our analyses provide strong evidence that the measured calcium traces in hepatocytes are prevalently of stochastic nature. In particular, bursting calcium oscillations are temporally correlated Gaussian series distorted by a monotonic, instantaneous, time-independent function, whilst the spiking behavior appears to have a dynamical nonlinear component whereby the overall determinism level is still low. The biological importance of this finding is discussed in relation to the mechanisms incorporated in mathematical models as well as the role of stochasticity and determinism at cellular and tissue levels which resemble typical statistical and thermodynamic effects in physics. dynamic systems stochastic processes cellular signaling calcium oscillations time series analyses noise temporal correlation dinamični sistemi stohastični procesi celični sistemi kalcijeve oscilacije analize časovnih zaporedij hrup časovne korelacije true true false Angleški jezik Slovenski jezik Članek v reviji 2012-06-07 12:08:56 2012-06-07 12:08:56 2024-05-27 13:37:45 2019-07-10 14:00:27 2008 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 539.2:519.216 15744008 0301-4622 URN:SI:UM:DK:8TFS75PU http://dx.doi.org/10.1016/j.bpc.2007.10.002 1 https://dk.um.si/Dokument.php?lang=slv&id=46701 Fakulteta za naravoslovje in matematiko 0 0 0