Differences in inhibition of PGI2 production by aspirin in rabbit artery and vein segments

We have studied the prostaglandin I2 production by endothelial and subendothelial cells of rabbit aortae and vena cavae. Rabbits were injected intravenously with 0, 10 or 100 mg/kg aspirin. One, 3, 6 or 30 hours later, segments of thoracic aorta or inferior vena cava were removed and their capacity to produce prostaglandin I2 was measured, using a bioassay system. Both endothelial and subendothelial cells of the arteries and veins produced …