CONTROL OF HUMAN VASCULAR SMOOTH-MUSCLE CELL-PROLIFERATION BY SERA DERIVED FROM EXPERIMENTALLY STRESSED INDIVIDUALS

Recently we reported that individuals with high scores in standardized hostility evaluation tests, when placed in a 'relaxed' environment, m ay have an association with increases in a blood-borne mitogenic subst ance(s) for arterial smooth muscle cells. To further investigate the m olecular basis for such an association, PDS [plasma derived serum with platelet derived growth factor (PDGF) removed] from individuals showi ng the greatest differential pre/post-stress mitogenic activity, were tested for ability to modulate changes in the steady state of the c-my c mRNA in cultured VSMC (vascular smooth muscle cells) by Northern blo t analysis. Post-stress PDS resulted in a significant increase in c-my c mRNA, when compared with pre-stress PDS of the same individual. Thes e results give further experimental support for the notion that stress (even in the form of transient, episodic psychological challenges) ma y affect the cardiovascular system via rapid elicited rises in serum m itogenic activity for VSMC.