Laropiprant Attenuates EP3 and TP Prostanoid Receptor-Mediated Thrombus Formation
Figure 6
Laropiprant at 10 µmol/L and niacin inhibit in vitro thrombus formation.
Whole blood was incubated with the fluorescent dye 3,3′-dihexyloxacarbocyanine iodide, perfused over collagen-coated channels, and thrombus formation was recorded by fluorescence microscopy. The images were taken 3 minutes after the start of the perfusion and are representative of 4 different experiments. (A) Vehicle-treated samples showed pronounced and rapid thrombogenesis over collagen. Treatment of whole blood with acetylsalicylic acid (1 mmol/L), laropiprant 10 µmol/L and niacin 3 mmol/L for 30 min, caused a marked reduction of thrombus formation, while laropiprant 1 µmol/L had no effect. The antithrombotic effect of niacin was not influenced by pretreatment of blood with acetylsalicylic acid or laropiprant. Thrombus-covered area was calculated by computerized image analysis and is expressed as percent of control (vehicle) response. (B) Original fluorescence images. Values are shown as mean+SEM. *P<0.05 versus vehicle.