Intracellular Ca²⁺ ions play an important role in transmitting and interpreting information that cells obtain from ambient environment. Having received an external signal, the cell may increase the intracellular Ca²⁺ concentration within fractions of second by a factor of several hundreds. This phenomenon triggers activation of various cellular systems that generate a response to the external stimulus. The Ca²⁺ concentration increases in many cells under the effect of an external signal and, apart from it, starts oscillating. Both the frequency and amplitude of those oscillations are influenced by the external signal strength. There are reasons to hypothesize that the conversion of the external signal into the oscillating intracellular signal has some important informational meaning. Methods to measure dynamics of the intracellular Ca²⁺ concentration and mechanisms that generate those oscillations are reviewed, and the hypotheses how the cell decodes Ca²⁺ concentration oscillations are presented. The consideration is focused on the platelet, the cell that pays a key role in arrest of hemorrhage. If a vessel is damaged, the platelet is rapidly activated. Identical platelets are divided in the process of arresting hemorrhage into three populations with quite different missions. The platelet seems to somehow 'interpret' the set of external signals and uses the Ca²⁺ concentration oscillations to 'choose' the population to which it will belong. Owing to the platelet's relative simplicity, there are hopes that the studies of that cell will shortly enable deciphering of the 'code' that drives the Ca²⁺ concentration oscillations.

Keywords: intracellular calcium concentration oscillations, platelets, coding, decoding, Poincaré—Andronov—Hopf bifurcation PACS: 87.10.Ed, 87.16.−b, 87.19.−j (all) DOI: 10.3367/UFNe.2018.05.038335 URL: https://ufn.ru/en/articles/2019/7/c/ 000492057500003 2-s2.0-85076769073 2019PhyU...62..660S Citation: Shakhidzhanov S S, Balabin F A, Obydennyi S I, Ataullakhanov F I, Sveshnikova A N "Calcium oscillations in blood platelets and their possible role in 'interpreting' extracellular information by cells" Phys. Usp. 62 660–674 (2019) BibTexBibNote ® (generic)BibNote ® (RIS)MedlineRefWorks Received: 8th, May 2018, accepted: 10th, May 2018 Оригинал: Шахиджанов С С, Балабин Ф А, Обыденный С И, Атауллаханов Ф И, Свешникова А Н «Кальциевые осцилляции в тромбоцитах крови и их возможная роль в "интерпретации" клеткой информации из внешнего мира» УФН 189 703–719 (2019); DOI: 10.3367/UFNr.2018.05.038335