Stimulation of prostacyclin synthesis by nizofenone

The effect of nizofenone on prostacyclin synthesis was investigated using rat arterial walls. Incubation of arterial walls with [14C] arachidonic acid resulted in a time-dependent formation of prostacyclin, which was radiochromatographically detected as the stable breakdown product, 6-keto prostaglandin F1 alpha. The addition of nizofenone dose-dependently stimulated the prostacyclin formation, and significant increases of 47 and 106% were observed at 0.1 and 0.3 mM, respectively. No stimulation of prostaglandin E2 and thromboxane A2 synthesis was observed in the experiments with ram seminal vesicle microsomes and human platelet microsomes. These findings suggest that nizofenone has a selective stimulatory action on prostacyclin synthesis.