Stable analogues of prostacyclin and thromboxane A2 display contradictory influences on atherosclerotic properties of cells cultured from human aorta. The effect of calcium antagonists.

We examined the influence of stable prostacyclin analogues (carbacyclin) and thromboxane A2 (U46619) on atherosclerotic properties of cells: [3H]thymidine incorporation and intracellular cholesterol content. A primary culture of human aortic subendothelial cells derived from atherosclerotic plaques was used. Carbacyclin exerted a direct anti-atherosclerotic effect, significantly reducing atherosclerotic manifestations of cells, while agent U46619 stimulated proliferation and cholesterol accumulation, i.e. demonstrated atherogenic potency in culture. Calcium antagonists (verapamil and diltiazem) markedly enhanced anti-atherosclerotic properties of carbacyclin and restricted the atherogenicity of U46619.