抄録
1. Oxygen consumption of mouse liver slices and incorporation of inorganic phosphate into various phosphate fractions (total acid-soluble, inorganic, acidsoluble organic, easily hydrolyzable organic phosphate, lipid, nucleic acids and protein fractions) were measured simultaneously employing radioactive phosphate.
2. Incorporation of P32 into acid-soluble organic phosphate fraction was found to be closely related to the oxygen consumption under the influences of cyanide and anaerobiosis.
3. A measure for estimating the relative rate of oxidative phosphorylation of tissue slices was developed, employing the ratio of P32 incorpolated into the acidsoluble organic phosphate fraction (c. p.m.) to the amount of oxygen consumed (μl).
4. Employing the P32/O2 ratio as a measure, 2, 4-dinitrophenol was proved to influence upon oxidative phosphorylation of mouse liver slices in an inhibitory way.
5. Thyroxine at a high concentration of 10-4M and, when pre-incubated, at lower concentrations of 10-6M and 10-7M decreased P32/O2 ratio markedly, while, without pre-incubation, thyroxine effect was rather stimulating at lower concentrations, the physiological significance of this result being discussed.
