Studies on normal and neoplastic mitochondria. II. Phosphorylation.

Oxidative phosphorylation has been studied in mitochondria and homogenates of six normal and five solid neoplastic rat tissues by determination of P :0 and control ratios and through the use of fluoride and dinitrophenol. In mitochondria prepared from the eleven tissues, P :O ratios with glutamate varied from 2.2 to 2.8, and with succinate from 1.1 to 2.0. Similar control of respiration by phosphate acceptor (control ratios of 2.9 to 18.3) was found in all the mitochondria, and the responses to fluoride and dinitrophenol addition were similar. Differences in the response of the various homogenates to dinitrophenol and fluoride addition were thought to be best explained by a difference in the balance of respiratory nitrogen (mitochondria) to high energy phosphate-splitting particles.