Fig. 2. The response of the pyrrolizidine alkaloid (PA) cell to 10^-7 mol l^-1 seneciphylline N-oxide after recent feeding on Senecio longilobus: (A) control vs 6-h exposure, (B) control vs 24- or 48-h exposure. Numbers in parentheses indicate number of replicates in each treatment. Arrows indicate median values. Asterisks indicate significant difference from controls using Dunnett's test at P<0.05.