Figure 6.

Linear relationship between mean of IPIs and $1/N_{\text{IPR}}$, the reciprocal of the number of IP₃R at a puff site. $N_{\text{IPR}}$ is chosen to be 3 ∼ 15, 20, and 25. For each value of $N_{\text{IPR}}$, means of IPIs for two different [IP₃]s, 0.1 μM and 0.2 μM, are computed and expressed as mean ± SE. For each [IP₃], a least-square linear fitting is performed and plotted using a solid line. We set $a_{h_{42}}=1$ s⁻¹.