Figure 3

Toxicity towards HT29 cells of putrescine and cadaverine. HT29 cells were grown in flat-bottomed microplates for 20 h, and then exposed to increasing amounts of (A) putrescine (5, 20, 40, 60 and 100 mM) or (B) cadaverine (5, 20, 40, 70 and 90 mM) for 24 h. Cells were observed using an inverted optical microscope (magnification 40x).