Prostacyclin, thromboxane A2 and calcium antagonists: effects on atherosclerotic characteristics of vascular cells.

We investigated the effects of stable analogues of prostacyclin (carbacyclin) and thromboxane A2 (U46619) and various calcium antagonists on atherosclerotic cellular indices, intracellular cholesterol content and [3H]thymidine incorporation. Primary culture of human subendothelial cells derived from atherosclerotic plaques of aorta was used. Carbacyclin reduced cholesterol accumulation and cell proliferation. U46619 in opposite to carbacyclin stimulated this processes. In general, carbacyclin exerted a direct antiatherosclerotic and U46619 - atherogenic action in culture. Calcium antagonists: dihydropyridines, verapamil derivatives and diltiazem demonstrated antiatherosclerotic properties themselves and potentiated carbacyclin effect but restricted atherogenicity of U46619.