Figure 3. Cav-1 KO ASMCs cultured in the presence but not absence of polyamine show higher DNA synthesis rate than WT cells.

DNA synthesis was assessed by measuring incorporation of [³H]thymidine into newly synthesized DNA. The experiments were performed using 5% of dialysed FBS (A) lacking polyamines or non-dialysed 5% FBS containing polyamines, as demonstrated by HPLC (B). The molecular weight cut-off for the dialysed FBS was 6 kDa. Treatment with exogenous putrescine (Put, 50 μM) for 2 h enhances DNA synthesis in Cav-1 KO, but not WT cells cultured in dialysed FBS (B). Values are presented as the means±S.E.M. n=6–9 for each group. Three replicate cultures were performed.*and ** represent P<0.05 and P<0.01, respectively.