Cell cycle kinetics and metabolism of Ehrlich ascites tumor cells in the presence of chloramphenicol as inhibitor of mitochondrial protein synthesis.
In the presence of 150 micrograms/ml of chloramphenicol, viability (dye exclusion test) of Ehrlich ascites tumor cells is not severely affected within 48 h; however the number of dead cells increases above this concentration; more than 10 mg/ml render all of the cells dye-positive within a culture period of 24 h. With the highest concentration tested (25 mg/ml) cells begin to lose viability 8 h after beginning of treatment. In the first passage in the presence of the antibiotic, proliferation of the cells is reduced by about 50%; in the second passage cell growth was about 65% that of controls. As is shown by flow cytometric analysis and BrdU-H33258 technique of flow cytometry, the reduction of proliferation in the second passage is caused by retardation of cell cycle progression of about 8 h; in the third passage the cell cycle is delayed by further 8 h as compared to controls. On recultivation in the third passage in the absence of the inhibitor an increase of cell number of about 75% of controls was observed. Lactate production and glucose uptake of the cells were stimulated by the inhibitor by about 20%; oxygen consumption was 60% that of controls after 24 h; however the ATP/ADP ratio of chloramphenicol treated cells was in the range of controls. Over a time period of 24 h the incorporation of [2-14C]thymidine is reduced to 34 +/- 3%, incorporation of [2-14C]uridine was 88 +/- 4% that of controls, incorporation of [U-14C]lysine was not significantly affected by 150 micrograms/ml of chloramphenicol; the same was found for the uptake of [2-14C]-alpha-aminoisobutyric acid. Electron micrographs of chloramphenicol treated cells reveal a high amplitude of swelling of all mitochondria with a translucent appearance of the inner compartment. The mitochondrial membranes remain largely intact but the number of cristae is drastically reduced.
D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D002701:Chloramphenicol / Q000494:pharmacology*; D004273:DNA, Neoplasm / Q000096:biosynthesis; D051379:Mice; D008854:Microscopy, Electron; D008928:Mitochondria / Q000378:metabolism; D009363:Neoplasm Proteins / Q000096:biosynthesis; D012334:RNA, Neoplasm / Q000096:biosynthesis
D004273:DNA, Neoplasm; D009363:Neoplasm Proteins; D012334:RNA, Neoplasm; D002701:Chloramphenicol