The idea of the special role of calcium in biology dates back to the 19th century when almost immediately aft er the discovery of calcium as an inorganic element (Davy, 1808), its role was established in the formation of mammalian bones, as well as other mineralized tissues found in the biological diversity of the animal world. Th e next stage was the observation by the prominent English physiologist Sydney Ringer (S. Ringer), which he made closer to the end of the XIX century. Ringer found that isolated frog heart survives much better while maintaining contractile activity in tap water compared to distilled. It turned out that the reason for such a "life-giving" action of water from the London water supply system was its high calcium content (in a concentration, as it turned out, of the order of a millimole). Th e next breakthrough in understanding the role of calcium occurred already in the 40s of the last century when Heilbrunn (L. Heilbrunn) introduced calcium into muscle fi bers through their trimmed ends and thus caused muscle contraction. In 1942, K. Bailey explained this phenomenon, showing that the ATPase activity of myosin is critically activated by calcium. Further research allowed the discoverer of the transmitter role of acetylcholine O. Levy (O. Loewy) to joke in 1959: "Calcium is everything!". However, it took another couple of decades to establish how this "everything" is everything.