Endotoxin, PAF and arterial thrombosis.

Using an optoelectronic device, we demonstrated that endotoxin modulates platelet-activating factor (PAF)-induced arterial thrombosis in a mesenteric artery of the guinea-pig. Indeed, topical superfusion by PAF induces the generation of platelet-vessel wall interactions, invariably followed by thrombus formation. A low dose of endotoxin markedly increased, while a high dose significantly reduced thrombus formation. The reducing effect of the high dose can be completely offset by indometacin, indicating the involvement of prostaglandin I2.