Stretch induces HASMC hypertrophy and hyperplasia. HASMCs were stimulated with a 1-h stretch for every 12-h period, and then cell size, DNA synthesis, protein synthesis (A), protein/DNA ratio (B), and cell count (C) were analyzed for the indicated periods. *, p < 0.05 versus control without stretch (white bar) for the indicated time point. Each bar indicates mean ± S.E. (n = 3).