Fig. 4.
Components of the CCh-induced [Ca2+]i transient: successive cumulative inhibitions of RyRs, IP3Rs and VGCCs. The fluo-4 loaded SMC was stimulated with 10 μM CCh (600-ms pulse) and imaged at 31 Hz. A 10-min period was allowed between CCh pulses. The time course of the normalized fluo-4 fluorescence averaged within seven sub-PM regions (outlined) was plotted in control (a), and following successive cumulative inhibitions by 50 μM tetracaine (b), 2 μM xestospongin C (c) and 5 μM nicardipine (d). The galleries below the plot show sequential images (after rotation by 90°) taken during the highlighted period.