Fig. 5

L(+)-lactate concentration was measured as indicator of L-lactate dehydrogenase activity in PA28y overexpressing (B8y) and control cells (B8vc) with respect to 3-BrPA treatment and nutrient deprivation. c(3-BrPA) – concentration of 3-BrPA; ∆FUnorm – normalized difference of fluorescence units. a Mean values of normalized differences in FU ± SEM are presented. Results gained with media containing 10% FBS are indicated by full lines; under starvation at 0.2% FBS, cell lines are marked with an asterisk and results are displayed by dotted lines. Concentration ranges with significant differences (p < 0.05) in L(+)-lactate concentration compared to starved cells are marked by horizontal lines and asterisks. b Correlations between L(+)-lactate concentration and agent concentration as logarithmic regression functions. For details of statistics see Additional file 4