Diet-induced hypercholesterolemia inhibits the recovery of prostacyclin production by injured rabbit aorta.

The effect of diet-induced hypercholesterolemia on the recovery of prostacyclin (PGI2) synthetic capacity was assessed at the luminal surface of previously injured rabbit aorta. Prostacyclin synthesis and release were measured by radioimmunoassay following arachidonic acid stimulation of deendothelialized and reendothelialized aortas of hypercholesterolemic rabbits. Assay of PGI2 production by aorta was performed at 15, 35, and 70 days following removal of endothelium with a balloon catheter. Prostacyclin production by both deendothelialized and reendothelialized areas of aorta from normocholesterolemic rabbits was initially low following injury and increased with time, reaching levels at 70 days equal to uninjured aortas. Prostacyclin production by both deendothelialized and reendothelialized areas of aorta from rabbits with moderately elevated serum cholesterol concentrations (203 to 350 mg/dl) was also initially low, but in contrast to normocholesterolemic rabbits, it did not increase with time. Results indicate that hypercholesterolemia like that seen in humans inhibits the recovery of PGI2 production in deendothelialized and reendothelialized areas of previously injured rabbit aorta.