Figure 4. MCa effect on RyR2 gating properties.

Representative current traces of control and MCa-induced RyR2 channel activity. Purified RyR2 was incorporated in a planar lipid bilayer and its single-channel activity recorded as described in the Experimental section. The holding potential was −80 mV in (A) and +80 mV in (B). The conductance of RyR2 was approx. 500 pS. The time duration of each record is 20 s. The closed and opened states of the channel are designated by C and O respectively. MCa was applied at a concentration of 500 nM in the cis chamber containing a free Ca²⁺ concentration of 472 nM.