Nuclear calcium transients: Hermes Propylaios in the heart.

O cunning guide, son of Maia, I fear that you might steal my lyre and my curved bow. For you hold the office from Zeus to establish deeds of exchange among men throughout the fertile earth. But if you would suffer to swear the great oath of the gods for me, either by nodding your head or by the mighty water of the Styx, you would accomplish everything pleasing to my own heart. —Homeric Hymnes 1 I n Greek Mythology, Hermes (Greek: Ἑρμῆς), son of Zeus and the pleiad Maia, was perhaps the most complex deity of transitions and boundaries, contemporarily simplified as a messenger god that moved freely between the higher worlds at Olympus, our world with human mortals, and the grim underworld of the deceased. As the second youngest of the Olympian gods and symbolizing Hermes' function as divine messenger, he is often sculptured as a youngster with winged sandals and winged cap and holding his symbolic herald's staff, the Greek kerykeion, consisting of 2 snakes wrapped around a winged staff. Hermes received multiple epithets including Propylaios, freely translated as " at the gateway, " reflecting a deeper philosophical significance of Hermes. As with all imaginary Greek deities, Hermes' actions do not describe a uniformly positive character. Tales rather tell of a complex, 3-layered personality, ranging from a truly uplifting spirit, as would be expected from his divine roots, to a character with an innocent yet cunning nature, but at times he also displayed unexpected evil. With these 3 faces, Hermes likely symbolized how our Greek ancestors segmented the universe, consisting of a noble and divine upper world physically located at Mount Olympus; planet Earth with all its living creatures including mankind; and finally, the dark side of disease, suffering, and death, represented by the underworld. The multifaceted roles that calcium plays in the heart may well bear analogy to the mythological character Hermes. First and foremost, for the maintenance of cardiac contraction, there may be no more important ion than calcium. During each heartbeat, a small leak of calcium through voltage-dependent L-type calcium channels triggers massive calcium release from the sarcoplasmatic reticulum (SR) through SR-bound ryanodine receptors (RyR2) into the cytoplasm of heart muscle cells, which triggers muscle contraction in a process referred to as excitation-contraction coupling. 2 Cardiac relaxation is initiated by the concerted action of the sodium-calcium exchanger and muscle-specific SR calcium ATPase-2 (SERCA2), which …