Figure 5: Effect of antioxidants incapable of membrane association.

(a) HeLa cells were incubated for 24 h with 200 μM HRP (cyan triangles) or 200 μM α-tocopherol (green squares) or left untreated (black dots). Cells were washed free of exogenous antioxidants and laser wounded in the presence of calcium. One population of untreated cells was injured in PBS-containing HRP (magenta dots) or injured in the absence of calcium (red dots). Only cells that were loaded before wounding with α-tocopherol displayed a significant (P<0.05; n=17) decrease in dye uptake. (b) HeLa cells were injured in the presence or absence of 10 mM DTT (cyan triangles). Cells injured in the presence of DTT did not display a significant difference in dye uptake kinetics when compared with controls injured plus (black dots) or minus (red triangles) calcium. (c) BS-C-1 cells were injured in the presence of 10 mM DTT (cyan diamonds). Cells injured in the presence of DTT displayed no significant difference in dye uptake kinetics when compared with control untreated cells (black dots). The data representing wounding in the absence of Ca²⁺ is also shown (red triangles). Data are presented as the mean±s.e.m.