Fig. 6. Treatment with 3-MA reduces MDC labelling of swollen, lysosomal vacuoles. M9 cells were grown in regular medium (A,C) or in medium supplemented with 10 mM 3-MA for 3 days (B,D) and selected cultures were incubated with U18666A for the final 24 hours (C,D). Cells were incubated with MDC and Nile Red for 10 minutes and images of MDC labelling of unfixed cells are shown. (E) Mean MDC labelling intensity of lysosomal vacuoles positive for Nile Red was quantified in untreated M9 cells as well as in U18666A-treated M9 cells in the presence or absence of 3-MA (mean±s.d. of three independent experiments). MLBs present in untreated M9 cells and cells treated with U18666A are strongly labelled for MDC, however MDC labelling of swollen, lysosomal vacuoles formed in the presence of 3-MA treatment is significantly reduced. *P<0.005 when compared to intensity in control M9 cells. Bar, 10 µm.