Fig. 3.

VSMC during aging. (A) Chemotatic response to a PDGF-BB gradient is increased in early passage VSMC from the aortic media of old rats compared with those from younger rats. VSMC within the older aorta are primed to respond to the growth factor. (From Pauly RR, Passaniti A, Crow M, et al. Experimental models that mimic the differentiation and dedifferentiation of vascular cells. Circulation 1992;86(Suppl):III68–73; with permission.) (B) Growth curves of VSMC cultured from young and old rat aortae. The number of VSMC obtained from old rats was significantly higher at days 3, 7, and 14. (From Li Z, Cheng H, Lederer WJ, et al. Enhanced proliferation and migration and altered cytoskeletal proteins in early passage smooth muscle cells from young and old rat aortic explants. Exp Mol Pathol 1997;64(1):1–11; with permission.)