Effects of succinylacetone on growth and respiration of L1210 leukemia cells

4,6-Dioxoheptanoic acid (succinylacetone, SA), a potent inhibitor of heme biosynthesis, suppressed growth and decreased respiration of L1210 leukemia cells in vitro. Growth of cells incubated in the presence of 2--4 mM SA for the first 2 days declined, and after 3 days virtually ceased. L1210 cells in the logarithmic growth phase exhibited active respiration (40 +/- 9.3 nanoatoms oxygen/min X 10(7) cells at 37 degrees C) which was inhibited by and released by uncouplers of oxidative phosphorylation. These and other inhibitors of mitochondrial function clearly demonstrate a mitochondrial basis for the cellular respiration in both control and SA-treated cells. L1210 cells in the stationary phase exhibited a marked decrease in oxygen consumption compared to cells in logarithmic growth. At the concentrations used in this study, SA was not immediately toxic to L1210 cells, but inhibited growth at 2 days without lowering levels of cellular heme. Thus, it appears unlikely that inhibition of growth of L1210 cells by SA can be ascribed either to heme depletion or to impairment of respiration.