Induction of chromatin condensation of VSMCs by piolitazone. A. Pioglitazone induced chromatin condensation in the nuclei of VSMCs. VSMCs were seeded on top of coverslips and transfected with vector, wt-PPARγ, or siRNA-PPARγ, respectively. Cells (non-transduced and transduced) were then treated with different drugs as shown followed by Hoechst staining. Arrows indicate the nuclei with condensed chromatin. B. Quantification of condensed chromatin from apoptotic VSMCs. The numbers of VSMCs from different treatments were counted. The percentage of condensed-chromatin positive cells was determined. **P < 0.001, *P < 0.01. Values are presented as the mean ± SEM of three different fields. Each experiment has been repeated three times.