Figure 5. Percentage response of antiaggregation against the concentration of authentic nitric oxide (NO) (A) (n = 7) or prostacyclin (PGI²) (B) (n = 7). (C) The synergic effect of NO and PGI²on antiaggregation. Simultaneous application of subthreshold concentrations of NO (200 nM) and PGI²(100 nM) enhanced the antiaggregation to 77.0 plus/minus 7.6% (n = 4). *Significantly different from separate application of NO or PGI².