Fig. 3.

pH dependence of proliferation parameters. Relative cell count (white bars), WST-1 metabolism (gray bars) and ATP content (black bars) are given for 3 (A) and 6 (B) days in culture. All data were normalized to their means of pH 7.4 on day 6. All parameters were increased with culture time and more alkaline medium pH. Each column represents the mean of ten wells collected from different culture plates. The data were analyzed by a RM ANOVA. Significant differences (p<0.05), referring to the pH 7.4 (control) values at their corresponding days are indicated by asterisks. A strong increase at alkaline pH was found in the WST-1 metabolism already on day 3, whereas the other parameters showed a delayed increase.