Figure 2. AdA is a potent agonist of all three IP₃ receptor subtypes.

(A) Concentration-dependent effects of AdA on Ca²⁺ release from the intracellular stores of cells expressing IP₃R1, IP₃R2 or IP₃R3. All results are expressed as percentages of the Ca²⁺ release evoked by ionomycin. The same colour codes are used in all subsequent figures. (B) Comparison, for each IP₃R subtype, of the Ca²⁺ release evoked by IP₃ and AdA. Results are means ± SEM from the number of independent experiments given in Table 1. Here, and in many subsequent figures, some error bars are smaller than the symbols.