Glial calcium signaling in physiology and pathophysiology

Neuronal-glial circuits underlie integrative processes in the nervous system. Function of glial syncytium is, to a very large extent, regulated by the intracellular calcium signaling system. Glial calcium signals are triggered by activation of multiple receptors, expressed in glial membrane, which regulate both Ca²⁺ entry and Ca²⁺ release from the endoplasmic reticulum. The endoplasmic reticulum also endows glial cells with intracellular excitable media, which is able to produce and maintain long-ranging signaling in a form of propagating Ca²⁺ waves. In pathological conditions, calcium signals regulate glial response to injury, which might have both protective and detrimental effects on the nervous tissue.