CHANGES IN THE ACTIVITIES OF MITOCHONDRIAL-ENZYMES IN THE PROGRESS OFTUMORIGENESIS OF BLADDER-CANCER

To investigate changes in the activities of mitochondrial enzymes in t he progress of tumorigenesis of bladder cancer, N-butyl-N-(4-hydroxybu tyl) nitrosamine (BBN) carcinogen was administered orally to male Spra gue-Dawley rats for eight weeks. The urinary bladders were harvested p eriodically for the evaluation of tumorigenesis. The activities of NAD H cytochrome c reductase (NCCR), succinate cytochrone c reductase (SCC R) and cytochrome c oxidase (CCO) were measured. The NCCR and SCCR act ivities elevated significantly by the exposure of BBN and decreased ra pidly when BBN was withdrawn. However, the CCO activity increased and reached plateau at 18 weeks in spite of the discontinuance of BBN. The results indicated that the NCCR, SCCR and CCO activities were signifi cantly elevated in the tumorigenesis. However, the CCO enzyme may be m ore related to the progress of tumorigenesis of bladder cancer.