Fig. 5.
Exogenous PA stimulates cell growth in SMCs. Quiescent SMCs were incubated with 100 μmol/l PA. A: cell number was counted 4 days after the PA treatment. B: DNA synthesis was determined 24 h after PA treatment by monitoring [3H]thymidine incorporation as noted in materials and methods. C: growth-arrested SMCs were preincubated with 100 μmol/l PA in the presence or absence of 0.3% 1-butanol for 30 min. Cells were then treated with 1 μmol/l 5-HT for 6 h. Cyclin D1 expression was detected by Western blot. Bar graphs represent means ± SD for n = 3. In A and B, * denotes a significant difference from the untreated controls at P < 0.05. In C, * denotes a significant difference from the untreated controls at P < 0.05. **Significant difference from 5-HT treated control and #significant difference from 5-HT + 1-butanol-treated cells.