Liver Of Adrenalectomized Rats Research Articles

Dexamethasone in oligemic shock. Physiochemical effects in monkeys.

It has been established that the anaerobic metabolism in oligemic shock is the product of decreased perfusion through nonvital tissues and is demonstrated by increased blood lactate-pyruvate ratio, and excess lactate as measured by Huckabee.1This is accompanied by a metabolic acidosis. Attempts at preventing this metabolic acidosis have led to the use of vasodilators to increase nonvital tissue perfusion and buffering systems. Neither of these adjuncts attack the biochemical defect which is the anaerobic production of lactic acid and the disassociation of lactic acid to produce the hydrogen ion. Exton and Park2demonstrated that the rate of conversion of lactate to glucose is diminished in perfused livers of adrenalectomized rats, and gluconeogenesis is enhanced when exogenous corticosteroids are instilled in the perfusant. This suggests the possibility that corticosteroid-stimulated gluconeogenesis from lactate may be utilized to decrease the amount of lactate in anaerobic tissue. Furthermore, corticoids in pharmacological

Studies on the metabolic N-demethylation. V. Effect of phenobarbital on the oxidative demethylation in vitro in the liver of adrenalectomized rats.

The activities of demethylating enzymes were decreased by adrenalectomy, but were stimulated by the administration of phenobarbital or cortisone in the liver of adrenalectomized rats. Incorporation of 14C-labeled amino acid into liver microsomal proteins of adrenalectomized rats was apparently increased by the administration of phenobarbital. The magnitude of phenobarbital-effect was decreased by pretreatment with puromycin and 8-azaguanine in intact animals.

Lipid peroxidation in tissues of whole-body x-irradiated rats and the effect of adrenalectomy.

Lipid peroxidizing activities in thymus, spleen, testis, kidney, brain and liver were studied in intact as well as in adrenalectomized rats which were exposed to 450 or 650 R of whole-body X-irradiation. Contents of lipid peroxides in these tissues, removed from both control and irradiated rats, were found negligibly small as compared to the amounts of lipid peroxides formed in tissue homogenates during aerobic incubations at 37°C for one hour in the presence and absence of added ascorbic acid. Lipid peroxidizing activities determined by the in vitro incubation, varied considerably between tissues, and no correlation was observed between morphologically defined radiation sensitivity of tissues and levels of lipid peroxidizing activity. The activity in liver increased to a considerable extent for some time after irradiation. A lag period was observed prior to the postirradiation increases in livers of intact but not of adrenalectomized rats irradiated with 450 R. The replacement therapy with cortisol acetate in adrenalectomized rats, did not modify the postirradiation changes. The maximal level of lipid peroxidizing activity in livers of adrenalectomized rats was lower than that of intact rats, a finding that was in contrast to the fact that all of the adrenalectomized rats, but none of the intact ones, died within 5 days after 650 R. Lipid peroxidation, therefore, did not seem to be correlated with the mortality of irradiated animals.

Failure of cycloheximide to induce tyrosine transaminase in the anesthetized rat.

It was recently reported that cycloheximide, an inhibitor of protein synthesis, induces tyrosine transaminase in the liver of adrenalectomized rats. We have been unable to confirm this effect in the anesthetized animal and our data show that cycloheximide inhibits the induction caused by hydrocortisone in adrenalectomized rats or by stress in intact rats.

Tryptophan Pyrrolase of Liver: III. CONJUGATION IN VIVO DURING COFACTOR INDUCTION BY TRYPTOPHAN ANALOGUES

Abstract Tryptophan pyrrolase, measured in an assay where its activity was proportional to its reaction with a specific antiserum, was induced in the liver of adrenalectomized rats by only those tryptophan analogues that also specifically promoted the conjugation of the apotryptophan pyrrolase in vitro and in vivo whether or not these analogues had affinity for the catalytic site of the tryptophan pyrrolase. The apotryptophan pyrrolase induced by hydrocortisone became conjugated upon injection of these analogues, and the elevated level was maintained in vivo as long as sufficient amount of the analogues was present. This action in vivo of the inducers with a site on the enzyme different from the catalytic site was associated with a decreased rate of disappearance of the protein and an increased rate of its synthesis.

Effects of primycin on the synthesis of tryptophan pyrrolase

1. In the liver of adrenalectomized rats a subtoxic dose of primycin inhibits the synthesis of tryptophan pyrrolase induced by hydrocortisone. 2. Primycin does not substantially affect the enhancement of the activity of TP observed in the liver of adrenalectromized animals after administration of 1-tryptophan. 3. The above effects of primycin are similar to those of actinomycin-D.

Carbohydrate synthesis in the isolated perfused rat liver: role of the adrenal cortex.

The synthesis of glucose by the isolated, perfused rat liver from pyruvate, lactate and alanine has been investigated. When the concentration of pyruvate in the medium was high (initial level 10-2M plus a constant infusion of 1 mg/min), formation of glucose proceeded rapidly in normal liver and the rate was not altered in livers of adrenalectomized or hypophysectomized animals. At a lower pyruvate concentration (2.5X10-3M plus a constant infusion of 0.25 mg/min), gluconeogenesis was reduced; however, the rate in normal and adrenalectomized livers was the same. Glucose production from lactate by normal and adrenalectomized livers was equal to that from pyruvate. When alanine was used as substrate in perfusion of normal liver, glucose synthesis was less than from pyruvate and lactate. Livers of adrenalectomized rats demonstrated a marked reduction in the rate of glucose formation from alanine which could be corrected by adding dexamethasone to the perfusion medium or by injecting the hormone into the donor ...

An inhibitory effect of glycyrrhizin on metabolic actions of cortisone.

It has been previously shown in our laboratory that glycyrrhizin inhibits the antigranulomatous action of cortisone without affecting the anti-inflammatory action in rats. In the present paper, the work was extended to include the effect of glycyrrhizin on metabolic actions of cortisone in the liver of adrenalectomized rats. Daily injections of cortisone induced a several fold increase of liver glycogen content, tryptophan pyrrolase activity and incorporation of [1-14C] acetate into cholesterol in rat liver, while concomitant injections of glycyrrhizin blocked these metabolic actions of cortisone. Administration of glycyrrhizin by itself, however, had no effect on the action of cortisone.

THE EFFECT OF DIFFERENT HORMONAL CONDITIONS ON THE CONCENTRATION AND OXIDOREDUCTION STATE OF THE NICOTINAMIDE NUCLEOTIDES OF RAT LIVER.

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.

Synthesis of 5-ribosyluracil in the liver of adrenalectomized rats treated with cortisone

Synthesis of 5-ribosyluracil in the liver of adrenalectomized rats treated with cortisone

Incorporation of C14-acetate in cholesterol and fatty acids of the liver of adrenalectomized rats during irradiation

Incorporation of C14-acetate in cholesterol and fatty acids of the liver of adrenalectomized rats during irradiation

A simple and rapid method for the biological assay of glucocorticoids.

IT has been well established that adrenocortical steroids have a pronounced effect on carbohydrate metabolism, in particular on the level of liver glycogen. Various methods for the assay of adrenocorticoids have been reported1,2, based upon the ability of these substances to cause a deposition of glycogen in the livers of adrenalectomized rats and mice. However, all these methods appear to be sufficiently complex and tedious to exclude their use when rapid screening procedures are desired. Van der Vies3 has described two colorimetric methods for the determination of glycogen in body tissues.

Adrenalectomy and basal metabolism of parabiotic rats.

ArticleAdrenalectomy and Basal Metabolism of Parabiotic RatsBernhard HoelscherBernhard HoelscherFrom the Department of Physiology-Biophysics, USAF School of Aviation Medicine, Randolph Field, TexasPublished Online:31 Dec 1954https://doi.org/10.1152/ajplegacy.1954.180.1.23MoreSectionsPDF (750 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByIncorporation of C14-acetate in cholesterol and fatty acids of the liver of adrenalectomized rats during irradiationBulletin of Experimental Biology and Medicine, Vol. 57, No. 6 More from this issue > Volume 180Issue 1December 1954Pages 23-26 Copyright & PermissionsCopyright © 1954 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1954.180.1.23History Received 7 June 1954 Published online 31 December 1954 Published in print 31 December 1954 Metrics

Liver vitamin content and adrenal cortical function.

THAT extracts of the adrenal gland are capable of elevating the blood sugar level and liver glycogen stores has been known for some time (Britton and Silvette, 1932). Moreover, the ability to cause deposition of glycogen in the livers of adrenalectomized rats and mice has provided a useful basis for the assay of corticoid substances (Reinecke and Kendall, 1942; Venning, et al., 1946). In view of the importance of B-vitamins in carbohydrate metabolism, it seemed desirable to determine whether the effect of the adrenal cortex on glycogen formation in the liver is accompanied by an alteration in the vitamin content of the liver. This approach also seemed of interest in view of the reported implication of pantothenic acid in adrenal function and in cholesterol metabolism (Ralli and Dumm, 1952; Guehring et al., 1952). METHODS Adult female Holtzman rats were adrenalectomized under ether anaesthesia through a lumbar approach.