Iloprost is a synthetic analogue of prostacyclin PGI2. Iloprost commonly employed in the treatment of peripheral vascular disease and also indicated in the treatment of patients affected by systemic sclerosis (SSc) in the presence of severe Raynaud's phen

Iloprost dilates systemic and pulmonary arterial vascularbeds. Iloprost also affects platelet aggregation but the relevance of this effect to the treatment of pulmonary hypertension is unknown. The two diastereoisomers of iloprost differ in their potency in dilating blood vessels, with the 4S isomer substantially more potent than the 4R isomer.[2] Infusion of ZK 36374 (100 ng/kg/min, n = 6) had no effect on heart rate and cardiac output, but caused a 20% reduction in mean arterial blood pressure by peripheral vasodilation. In animals receiving solvent or no drug prior to thrombosis induction, the time to occlusive coronary artery thrombosis (TOT) was 30 +/- 2 minutes (mean +/- SEM, n = 17). Pretreatment with ZK 36374 (i.v. infusion; 100 ng/kg/min) prolonged TOT by 50% to 47 +/- 7 minutes (p less than 0.005, n = 6). This prolongation of TOT was not due to the lower blood pressure in the ZK 36374 group, as dihydralazine in a dose that lowered arterial blood pressure to the same extent had no effect on TOT (32 +/- 4 minutes, n = 4). The results indicate that ZK 36374 may be useful in delaying (or preventing) occlusive coronary artery thrombi[3].