Fig. 4.

Elementary Ca²⁺ release events evoked by IP₃. Ca²⁺ release occurs in three major events: blip, puff, and wave. Blips represent release of Ca²⁺ through a single IP₃R channel, which can be lone or part of the cluster. Puffs are characterized by coordinated opening of multiple channels organized into the cluster. Regenerative Ca²⁺ waves are attributed to activation of IP₃R across the entire cell. Both IP₃ and Ca²⁺ ignite Ca²⁺ release form neighboring IP₃R clusters