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PubMed · 9697219

Coarse-grained entropy rates quantify fast Ca2+ dynamics modulated by pharmacological stimulation.

M Palus·C Schöfl·A von zur Mühlen·G Brabant·K Prank
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Abstract

Calcium (Ca2+) is an ubiquitous intracellular messenger which regulates cellular processes, such as secretion, contraction, and cell proliferation. A variety of cell types respond to hormonal stimuli with periodic oscillations of the intracellular free Ca2+ concentration ([Ca2+]i) which can be modulated in their frequency in a dose-dependent manner. The period of these well-studied oscillations varies normally between 30 sec and a couple of minutes. Here we study [Ca2+]i oscillations in clonal beta cells (hamster insulin secreting cells, HIT) under pharmacological stimulation. Besides the well-known high-amplitude low frequency oscillations we try to analyze for the first time low-amplitude high frequency oscillations of [Ca2+]i under pharmacological stimulation which have not been explored in experimental approaches to date. Using coarse-grained entropy rates computed from information-theoretic functionals we demonstrate differences in temporal complexity of the fast low-amplitude [Ca2+]i dynamics corresponding to different phases of pharmacological stimulation which are additional to the well-known dose-dependent pattern of low-frequency high amplitude [Ca2+]i dynamics.

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AlgorithmsAnimalsArginine VasopressinCalciumCalcium SignalingCell LineComputer SimulationCricetinaeEntropyIslets of LangerhansKineticsModels, BiologicalOscillometrySecond Messenger SystemsTime FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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M Palus, C Schöfl, A von zur Mühlen, G Brabant, K Prank. 1998. Coarse-grained entropy rates quantify fast Ca2+ dynamics modulated by pharmacological stimulation.. https://pubmed.ncbi.nlm.nih.gov/9697219/

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