Staurosporine, a protein kinase C inhibitor interferes with proliferation of arterial smooth muscle cells.

Staurosporine (10 ng/ml and more), a protein kinase C inhibitor, inhibited the serum-stimulated growth of smooth muscle cells. This inhibitory effect proved to be linked to the inhibition of transition from the G0 to the S phase of the cell cycle, as measured by 5-bromodeoxyuridine incorporation into the nuclei. As this inhibitory effect of staurosporine was restricted to the first 10 hours of the stimulation, reactions which are essential for the signal transduction may be associated with actions of protein kinase C. The possibility that staurosporine may inhibit cell growth via inhibition of this step warrants further attention.