Abstract
1. The concentration and oxidoreduction state of the liver nicotinamide nucleotides of rats subjected to a number of hormonal treatments have been measured. 2. Adrenalectomy decreases the NADP(+) content by 80% but has little effect on NAD(+), NADH or NADPH. High doses of cortisone produce similar changes, but more physiological doses (5mug. daily) tend to increase the NADP(+) content. 3. Glucagon treatment of normal rats lowered the NADH and NADP(+) concentrations but did not affect the total amounts present. Growth hormone increased the concentrations and total amounts of NAD(+) and NADH but significantly decreased the concentrations and total amounts of NADP(+) and NADPH. 4. Measurements have been made of a number of enzymes in the livers of adrenalectomized and glucagon-treated rats that could affect the oxidoreduction state of NADP. The activities of glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase are not affected by adrenalectomy or treatment with cortisone or glucagon. Nor does adrenalectomy affect the activity of NADPH-cytochrome c oxidoreductase or NADPH-glutathione oxidoreductase. The hepatic content of glutathione is, however, decreased 50% by adrenalectomy. 5. Measurements of the oxidation of [1-(14)C]glucose and [6-(14)C]glucose by liver slices from adrenalectomized rats showed that glucose oxidation was substantially normal, although phenazine methosulphate caused a smaller stimulation of the oxidation of C-1 of [1-(14)C]glucose in slices from the livers of adrenalectomized rats than it did with slices from controls. The hepatic synthesis of lipids from [1-(14)C]glucose was marginally increased in adrenalectomized rats. 6. The additional NADP(+) found when liver is extracted with 0.02n-sulphuric acid-0.1m-sodium sulphate is less affected than the NADP(+) extracted with 0.1n-hydrochloric acid in adrenalectomized or glucagon-treated rats. Hooded Norway rats appear to have less of this extra form of NADP(+) than albino rats. 7. An attempt has been made to correlate the observed changes in the nicotinamide nucleotides with metabolic patterns prevailing in different hormonal conditions.