NOS1−/− mice show attenuated CaMKII-dependent leak.

A) Matched data such that [Ca]SRT was the same for all treatments (left) an resultant SR Ca leaks (right, n = 10–22). B) Matched data such that [Ca]SRT was the same in NOS1−/− and NOS1−/−+SNAP (left) and the resultant SR Ca leaks (right), demonstrates that SNAP restores the leak/load relationship in NOS1−/− myocytes. C) Summary data (top, n = 4 hearts each) and representative immunoblot (bottom) of phosphorylated RyR at CaMKII-specific residue, Ser2814, and total RyR expression in WT and NOS1−/− heart lysates. D) Western blots showing total CaMKII normalized to GAPDH (left) and CaMKII phosphorylated at T286 (right, n = 5) in WT and NOS1−/− hearts. Representative blot showing at bottom. E) Summary data (top) and representative immunoblot (bottom) of oxidize CaMKII after ISO stimulation in WT and NOS1−/− heart lysates. *Statistically different from control, # different from WT+ISO (t-test, p