Effects of DPI on GTN-triggered activation of sGC in the presence of purified ALDH2. Purified sGC was incubated at 37°C for 10 min with 4 µg of ALDH2 in the presence of 0.5 mM [α-32P]GTP, 1,000 units/ml SOD, and 1 mM NAD+ with DPI, GTN or DEA/NO as indiacted, followed by isolation of 32P-cGMP and determination of radioactivity by liquid scintillation counting. A: Effects of the indicated concentrations of DPI on sGC activity determined in the presence of GTN or DEA/NO (1 µM each). B: Activation of sGC by increasing concentrations of GTN in the absnece and presence of 10 µM DPI. The data are mean values ± S.E.M. (n=3-4).