Figure 2.

Astrocytes form an interconnected network through calcium. Astrocytes utilize the propagation of intercellular calcium (Ca²⁺) waves to achieve long-distance communication. There are two routes by which Ca²⁺ is mobilized through astrocytes: i) one pathway involves the passage of either IP₃ (orange dots) or Ca²⁺ (purple dots) through gap junction channels (green connexon) and ii) the other route depends on the release of ATP (green dots) through hemichannels (orange connexon), and subsequent activation of purinergic receptors (purple pore) in the same (autocrine) or in neighboring (paracrine) cells, which promote Ca²⁺ uptake.