[Interaction of 3-[3H]-2-n-nonyl-4-hydroxy-quinoline-N-oxide with submitochondrial particles of beef heart. I. Inhibition of the respiratory activity].

The inhibitory effect of 3-3H-2-n-nonyl-4-hydroxy-quinoline-N-oxide (3H-NQNO) on the respiration induced by NADH or by succinate was studied in submitochondrial particles from beef heart. Polarographic experiments showed that oxygen uptake by submitochondrial particles was inhibited by 3H-NQNO. Similar results were obtained with the unlabelled compound NQNO. The inhibitory activity of 3H-NQNO on the respiration was 2 or 3 times better than that of the heptyl derivatives (HQNO) and additive with that shown by antimycin.