Figure 2. Diastolic SR Ca²⁺ leak over the ryanodine receptor (RyR2).

(A) Diastolic SR Ca²⁺ leak in normal HEPES 1.8 Ca²⁺ concentration solution in LCR and HCR rats. (B) Exemplary recordings of diastolic SR Ca²⁺-leak in a LCR rat. (C) After incubation by AIP and (D), after inhibition by H-89. Note that LCR rats had significantly more diastolic SR Ca²⁺-leak than HCR rats in vehicle situation. In addition, inhibition of CamKII by AIP reduced the leak to of the LCR to equal that of HCR rats, but AIP had no further effect on HCR rats. PKA inhibition by H-89 did not have any significant effect in either of the groups. Number of rats used for cell experiments: LCR=5, HCR=5.