CORRELATION BETWEEN HUMAN VASCULAR SMOOTH-MUSCLE CELL-PROLIFERATION AND PROTEIN-KINASE C-ALPHA-EXPRESSION - EFFECT OF D-ALPHA-TOCOPHEROL

Population doublings of four different human aortic vascular smooth mu scle cell strains correlate with the amount of protein kinase C alpha present in these cells. d-alpha-Trocopherol inhibits, at different ext ents, protein kinase C activity in all cells studied. Furthermore, the extent of inhibition positively correlates with the amount of protein kinase C alpha expression and not with that of the other isoforms. It is suggested that, in human aortic smooth muscle cells, protein kinas e C alpha modulates cell proliferation and serves as a target for d-al pha-tocopherol inhibition.