PDE3 inhibitor milrinone reverses ODQ-induced decrease of cAMP. RBC from day 11 were incubated for 15 minutes at 37°C with 10 μmol/L NE (control); 10 μmol/L NE + 30 μmol/L ODQ; 10 μmol/L NE and 20 μmol/L milrinone (MIL); and 10 μmol/L NE, 30 μmol/L ODQ, and 20 μmol/L milrinone, respectively. Data are the mean values and SD from 5 experiments in each case. *Significant difference from control (P < .01).