Figure 3.
Effect of putrescine or ornithine on the cytostatic actions of DETA/NO, SNAP, and DFMO in RASMC. Cell proliferation was assessed by thymidine incorporation into DNA during a 24-h incubation, as described in Materials and Methods. Putrescine (100 μM) or ornithine (100 μM) was added to cells at the same time as test agents. Data were calculated as dpm/105 cells and expressed as percent of control (assigned 100%), where control represents cells grown in the absence of added test agents. *, significantly different (P < 0.05) from corresponding control (no additions). Data represent mean ± SE of duplicate determinations from five experiments.