14C] Alanine incorporation into proteins and their contents in the tissue of intact and adrenalectomized rabbits after hydrocortisone and cortitropin administration

A single administration of hydrocortisone to intact rabbits increases the incorporation of [14C] alanine into proteins of the brain and liver tissue homogenates and soluble fractions as well as in blood plasma proteins and reduces the label incorporation into the brain tissue proteins and reduces its incorporation into the blood plasma proteins. Adrenalcetomy is followed by an increase in the incorporation of [14C] alanine into proteins of the brain and muscle tissue homogenates and soluble fraction and into proteins of blood plasma and liver tissue homogenates as well as by reducing the label incorporation into the spleen soluble fraction proteins. ACTH administered to adrenalectomized rabbits reduces incorporation of [14C] alanine into the brain and muscle tissue proteins, total proteins of liver tissue homogenate and increases it into the proteins of the spleen tissue soluble fraction. Multiple administration of the soluble fraction hormones both to intact and adrenalectomized rabbits inhibits the label incorporation into the studied tissue proteins. Parallel with the change in [14C] alanine incorporation into proteins under the hormones effect certain shifts in their contents were also established.     

Hormonal control of metabolism of gamma-aminobutyric acid in the rat hypothalamus and hippocampus

It has been established that hydrocortisone administration increased the amount of total, free, bound and synaptosomal GABA in the hypothalamus, glutamate decarboxylase activity in the homogenate and synaptosomes and time of the mediator turnover. ACTH administration increased the GABA content and glutamate decarboxylase activity in synaptosomes. The total amino acid content and time of its turnover got higher only with single hormone administration. In the hippocamp hydrocortisone administration increased the total and free GABA contents, its turnover time, glutamate decarboxylase activity in the homogenate and decreased GABA-aminotransferase activity in the homogenate and synaptosomes. The GABA level in synaptosomes grew only with multiple hormone administration. Single administration of ACTH decreased the total GABA content, glutamate decarboxylase activity in the homogenate, while its multiple administration increased the GABA level in synaptosomes followed by a decrease of GABA-aminotransferase activity in the homogenate and synaptosomes. The GABA turnover time fell with single hormone administration and grew with the multiple one. Adrenalectomy induced no changes in the GABA content and activity of its metabolism enzymes in the hypothalamus, however the bound GABA level decreased, while the turnover time increased. In the hippocamp adrenalectomy decreased total, free and synaptosomal GABA contents, glutamate decarboxylase activity in a homogenate and turnover time. Subsequent hydrocortisone administration only partly normalized the revealed changes of the GABA metabolism in the brain structures under adrenalectomy.     

Effect of corticotropin and hydrocortisone on carbohydrate metabolism in skeletal muscles

The intraperitoneal administration of corticotropin (ACTH) in the rate of 1 and 2 units per 100 g of body weight and that of hydrocortisone in the rate of 1 mg and 5 mg per 100 g body weight were studied for their effects on carbohydrate metabolism rate in musculus gastrocnemius as well as on the level of 11-oxycorticosteroids in blood plasma of rats. The glycogen level in muscles was found to rise 3 hours after ACTH and hydrocortisone administration and it correlated with the hydrocortisone level increase in blood plasma (r = 0.714 and 0.863, respectively); the activity of pyruvate kinase decreased. Simultaneously ACTH did not change while hydrocortisone lowered the phosphorylase activity and the content of both fructose-6-phosphate and lactate.     

Changes in the activity of the brain renin-angiotensin system and in the functional state of the pituitary-adrenal system of rats under the influence of captopril]

While studying the effect of peroral captopril injections on the activity of renin-angiotensin system (RAS), the activity of angiotensin-converting enzyme (ACE) and angiotensin II content from anterior and mediobasal hypothalamus, medulla and adenohypophysis of intact rats has been established to decrease. Captopril administration decreases ACE activity which increases after hydrocortisone injection in rat medulla and striatum. Captopril results in no potentiation of hormonal effect in hypothalamus and in adenohypophysis where ACE activity decreases following hydrocortisone injection. A decrease in the RAS activity of brain structures and adenohypophysis induced by captopril administration to rats is accompanied by the inhibition of the activity in the pituitary-adrenal system. A decrease in ACTH level and in 11-hydroxycorticosteroids of the rat blood plasma has been determined after single captopril injection in the dosage of 10 and 50 mg/kg of body weight. Duration of the effect depends on the captopril dosage.     

Inhibition of glucocerebrosidase and induction of neural abnormality by cyclophellitol in mice.

Cyclophellitol, a cyclitol with an epoxide, is a novel microbial secondary metabolite that inhibits beta-glucosidase and beta-glucocerebrosidase. Daily administration of cyclophellitol induces a severe abnormality of the nervous system in mice while it has no toxicity in various cultured cells. It was shown to inhibit glucocerebrosidase in vivo significantly in mice and the content of glucocerebroside in liver, spleen, and brain was increased markedly. The enzyme activity was completely suppressed in brain, liver, spleen, kidney, and muscle. On the other hand hexosaminidase activity was not affected in all tissues. After a single administration of cyclophellitol the maximal inhibition of glucocerebrosidase was observed within 30 min in brain and liver, and the inhibition lasted for 2-4 days. A single administration of cyclophellitol also induced a severe abnormality of the nervous system known as Gaucher's-like disease in mice. Conduritol B epoxide is also known to inhibit glucocerebrosidase and induce Gaucher's like-disease in mice by repetitive injection. Cyclophellitol was shown to be more potent than conduritol B epoxide in inhibition of glucocerebrosidase and in induction of the neural abnormality.     

Specific binding of H3-GABA by synaptic membranes of hypothalamus and hippocampus in rats after adrenalectomy and administration of hydrocortisone and corticosterone]

It has been shown that single hydrocortisone administration increased 3H-GABA binding by hypothalamic synaptic membranes. ACTH administration enhanced binding in both studied brain structures. Multiple hydrocortisone administration did not effect 3H-GABA binding by hypothalamic and hippocampal membranes, while multiple ACTH administration caused the decrease in mediator binding by hypothalamic membranes and increased its level in hippocampal membranes. Adrenalectomy did not change 3H-gaba binding and single hydrocortisone administration to adrenalectomized rats increased 3H-GABA binding only by hypothalamic synaptic membranes.     

Cosinor analysis of diurnal changes of the reduced glutathione level in the blood, brain, liver and kidneys of mice, induced by ACTH administration

The influence of a single dose of ACTH(100 I.U. /kg body weight) on the diurnal rhythm of reduced glutathione (GSH) was studied in the blood and brain, liver and kidney homogenates of male mice. Cosinor analysis revealed that ACTH induces changes in the mean diurnal amount of GSH in the blood, brain, liver and kidneys. At the same time, GSH amplitudes in the blood and kidneys increased significantly, whereas in the case of brain and liver they decreased markedly. Moreover, it was found that ACTH induces a shift in GSH acrophases in the blood, brain, liver and kidneys as compared with the control values.     

Cortical tissue from syngenous brain as a stimulator of immunogenesis in thymectomized mice]

Experiments on CBA mice showed that the gray matter homogenate of the syngeneic brain contained components reconstituting the T-cell population in the spleen of thymectomized animals and possessing a stimulating effect on the immune response to sheep red blood cells. The white matter homogenate was much less active, it is not excluded that the trace activity is due to the gray matter admixture in the preparation. Syngeneic muscle tissue homogenate possessed no biological activity.     

The effect of stress on the activity of hepatic tryptophan pyrrolase, of tyrosine aminotransferase in various organs and on the level of tryptophan in the liver and plasma of rats.

In rats subjected to 400 revolutions in Noble-Collip drums, hepatic tryptophan pyrrolase activity increases and plasma tryptophan level decreases. After bilateral adrenalectomy, the alterations of plasma tryptophan are even more pronounced and liver tryptophan increases in contrast to tryptophan pyrrolase activity which remains unchanged after injury. The possible significance of the posttraumatic increase of tryptophan pyrrolase in intact animals for brain serotonin metabolism and hepatic gluconeogenesis is underlined. The activity of tyrosine aminotransferase in liver, brain, adrenal, kidney and muscle tissue of rats was determined with special reference to the possible effect of the before-mentioned stress procedure. Organ homogenates were centrifuged at 15000 x g and both supernatants and pellets were investigated for enzyme activity with the exception of the liver, where only the supernatant fraction was used. Tyrosine aminotransferase activity in the liver supernatant considerably exceeded the corresponding values in both supernatant and pellet of the remaining organs, in which a prevalence of the mitochondrial enzyme was obvious. In contrast to the clear-cut increase of the hepatic enzyme during stress, essentially no changes were noted in the brain, the adrenals, kidney or muscle under similar conditions...     

Parasitological and biochemical parameters in Schistosoma mansoni-infected mice treated with methanol extract from the plants Chenopodium ambrosioides, Conyza dioscorides and Sesbania sesban

This study aims to detect the antischistosomal properties of the plants' Chenopodium ambrosioides, Conyza dioscorides and Sesbania sesban methanol extract against Schistosoma mansoni in infected mice, including determination of total protein and albumin levels and the activities of alanine and aspartate transaminases (AlT, AsT) and acid and alkaline phosphatases (AcP and AkP) enzymes in the serum of infected treated mice. Male Swiss albino mice were infected with S. mansoni and orally treated with methanol extract of the plants C. ambrosioides (1250 mg/kg/day), C. dioscorides and S. sesban (1000 mg/kg/day from each) for 2 consecutive days 7 weeks post infection (PI). In addition, treatment of mice with the tested dose of each plant extract was successively done (i.e. the 1st extract followed by the 2nd and 3rd one with an hour interval). Parasitological and biochemical parameters were assessed. Nine weeks PI, the reduction rates of worm load/mouse treated with either C. dioscorides (1000 mg/kg), C. ambrosioides (1250 mg/kg) or S. sesban (1000 mg/kg) were 40.9%, 53.7% and 54.4%, respectively. Successive treatment raised the reduction rates of worm load/mouse to 66.3% and the ova/g tissue in liver to 76.9%. Moreover, serum total protein and albumin levels and activities of AlT, Ast, AcP and AkP enzymes of infected treated mice were improved in comparison with those of infected untreated ones. It is concluded that administration of C. dioscorides, C. ambrosioides and S. sesban methanol extract to infected mice exhibited a moderate antischistosomal effect. Successive treatment improved the antischistosomal properties of these plant species, hence ameliorated the liver functions of treated mice that may suggest degenerations of liver granulomas and regenerative changes.     

Selenium content and distribution in rat tissues irradiated with gamma rays

The effects of supplementation with selenous yeast and ionizing radiation on selenium (Se) content and distribution were evaluated in rat tissues (liver, kidney, spleen, heart, muscle, blood, front brain, hind brain, hypothalamus, pituitary, adrenal glands, testes, and hair). This study had 16 Se-supplemented (0.5 μg Se/d) and 16 placebo adult male Wistar rats. One half of the animals (eight Se-supplemented and eight placebos) were irradiated with a single dose of 4.2 Gy from a Co-60 source and sacrificed 7 d after irradiation along with nonirradiated animals and analyzed for Se content determination. The data obtained showed that selenous yeast supplementation increased Se levels in rat tissues (highest increases in hypothalamus, 161%; hind brain, 126%; spleen, 110%; and adrenal gland, 105%). Ionizing radiation induced significant changes in Se content and distribution (decrease in liver, blood, hair, femoral muscle, spleen, and hypothalamus; increase in kidney, testes, adrenal glands, and brain of placebo group). Supplementation with selenous yeast reduces changes in Se content and distribution after irradiation. It seems that the animal tissue susceptibility to oxidative damage may be correlated to their ability to retain Se in tissues.     

Formation of gamma-aminobutyric acid from glutamate and putrescine in rat hypothalamic and hippocampal synaptosomes and regulation of these processes by glucocorticoids]

It has been shown that single or multiple hydrocortisone and ACTH administrations to intact rats increased GABA content and its synthesis from glutamate and putrescine in synaptosomes of hypothalamus. The letter content was increased by single hormonal administration while multiple hormonal administration and adrenalectomy decreased it. Ornithine decarboxylase activity was increased by single hydrocortisone administration to intact animals, following adrenalectomy, and it was decreased by single hormonal administration to adrenalectomized rats. GABA synthesis in synaptosomes of hippocampus from putrescine was increased by single hydrocortisone and multiple hormonal administrations. GABA content was increased by multiple administration of both hormones and was decreased by adrenalectomy. Putrescine level was decreased by multiple hydrocortisone administration to intact and single administration to adrenalectomized rats; ornithine decarboxylase activity was decreased by multiple administration of both hormones.     

In vitro metabolism of opioid tetrapeptide agonists in various tissues and subcellular fractions from rats

The metabolism of three mu-selective opioid tetrapeptide agonists, Tyr-D-Arg-Phe-Nva-NH(2) (TArPN), Tyr-D-Arg-Phe-Phe-NH(2) (TArPP), and Tyr-D-Ala-Phe-Phe-NH(2) (TAPP), was investigated in different rat tissues. High metabolic activity (<20% peptide remaining after 30 min) was found against the three peptides in the kidney homogenate and against TArPN in spleen homogenate. Low metabolic activity (>80% peptide remaining after 30 min) was found for all peptides in brain homogenate and plasma, and for TArPN and TArPP in blood. The other tissue homogenates, prepared from the small and large intestine, liver and lung, all exhibited intermediate metabolic activity (20-80% peptide remaining after 30 min) against the peptides. In all tissues investigated, the tetrapeptides were metabolized at the C-terminal amide by deamidation.A further in depth metabolic investigation was performed in subcellular fractions isolated from three tissues (small intestine, liver and kidney). In the liver, the deamidation was predominantly localized to the mitochondrial/lysosomal fraction, while hydrolysis at the N-terminal Tyr residue was the major metabolic pathway in the microsomal/brush-border membrane fraction from the kidney and small intestine.     

Effect of hydrocortisone on ACTH, growth hormone, insulin and glucose in the blood of bilaterally adrenalectomized patients

This study is aimed at elucidating the mechanism of paradoxical rise in plasma ACTH levels in response to glucocorticoids, observed by several authors in bilaterally adrenalectomized patients with Cushing's disease. Six control subjects and fourteen patients bilaterally adrenalectomized for Cushing's disease were given a dose of 200 mg hydrocortisone sodium succinate by 3-5 mm i.v. injection. Plasma ACTH (in 6 patients), serum cortisol, growth hormone (GH) and insulin and blood glucose levels were estimated at 0, 30, 60, 90, and 120 minutes. The administration of hydrocortisone significantly suppressed plasma ACTH levels only at 60 min. In one case a slight rise in ACTH level during the test was observed. A significant fall in blood glucose levels was found only in the adrenalectomized patients. No significant changes in serum insulin and GH levels were noted. The possible mechanisms are discussed, especially the potential role of transient glucose deficiency in the pathophysiology of plasma ACTH increase in response to hydrocortisone in the bilaterally adrenalectomized patients.     

The effect of ACTH and diazepam on the uptake of tritiated uridine into brain, muscles and liver of infant rats.

In 2-day-old rats, ACTH increases the uptake of 3H-uridine in the brain; no such effects were observed in the msucle and liver tissue. Diazepam does not affect the uptake of 3H-uridine into the brain tissue, but decreases the uptake into the muscle tissue. In the brain tissue of infant rats, ACTH does not change the distribution of radioactivity of intraperitoneally administered 3H-uridine among U, Urd, UMP, UDP and UTP. Diazepam increases the amount of radioactivity, found at the U spot. In the muscle, both ACTH and Diazepam increases the amount of radioactivities found in the Urd spot. A significant correlation between the radioactivity of UMP+UDP+UTP and the specific activity of RNA was proved only in the brain. The ratio: specific activity of brain RNA/radioactivity of UMP+UDP+UTP was thus used as a tentative indicator of the biosynthesis of brain RNA. Neither ACTH nor diazepam altered this ratio in infant rats.     

Effect of hydrocortisone and dopamine on activity of beta-glucuronidase in lung parenchyma during experimental septic shock]

An effect of hydrocortisone and dopamine on beta-glucuronidase activity in the lung tissue in experimental septic shock was analysed. The study involved 30 mongrel dogs. Septic shock was induced with i.v. E. coli endotoxin. Total and free activity of beta-glucuronidase was determined with Talalay et al. technique in pulmonary parenchyma homogenate, mitochondrial-lysosomal fraction and supernatant. It was found, that hydrocortisone and dopamine given together increase the stability of the pulmonary lysosomes indicating a value of such management of the septic shock in man.     

Degradation of somatomedin A by various organ homogenates from rats

Degradative activities of somatomedin A (SMA) have been examined in various tissue homogenates of rat using trichloracetic acid precipitable radioactivity of 125I-SMA. Kidney and testis showed higher specific activities and liver and brain lower activities. They were dependent on SH reagents; 0.5 mM HgCl2 inhibited the degradative activity of liver completely and 1 mM dithiothreitol (DTT) augmented the activity slightly. The activities in liver were separated by differential centrifugation; about 90 per cent of the total activity in the whole homogenate was recovered in the supernatant fraction at 100,00 x g for 60 min, and 10 per cent in the precipitate. The pH profile of each fraction was different; that of the supernatant showed a single peak at pH 7.4 and that of the pellet revealed two peaks at pH 5.9 and 7.4. However, both fractions showed similar SH-dependency.     

Alterations in the activities of subcellular fractions marker enzymes in rat liver and brain by hydrocortisone and corticosterone treatment

The effect of subcutaneous injection of hydrocortisone and corticosterone on the activity values of some subcellular fractions marker enzymes from rat liver and brain was investigated and compared with controls (without treatment with hormones). The following enzymes were studied (subcellular fraction are shown between parentheses): N-acetyl-beta-D-glucosaminidase and beta-glucuronidase (lysosomes); succinate dehydrogenase = SDH (mitochondria); glucose-6-phosphatase (endoplasmic reticulum); 5'-nucleotidase and Na+-K+-Mg2+ ATPase (plasma membrane). The specific activity of lysosomal enzymes from liver showed no change when rats were injected either with hydrocortisone or corticosterone. The same enzymes from brain showed significant increases in their activities with both hydrocortisone or corticosterone except beta-glucuronidase; this enzyme gave activity values remaining between the control levels, after treatment with corticosterone. The activity of mitochondrial SDH was increased after corticosterone injection either in liver or brain. After hydrocortisone injection, its activity rises significantly in brain (72%), but it falls in liver compared to the control values. Glucose-6-phosphatase behaves similarly in brain or liver fractions; its activity increases always after corticosterone treatment and decreases by hydrocortisone. The plasma membrane marker enzymes did not change practically in brain fractions, excepted Na+-K+-Mg2+ ATPase which tends to rise its activity after hydrocortisone injection. In liver fractions, both 5'-nucleotidase and Na+-K+-Mg2+ ATPase activities increase either by corticosterone or hydrocortisone treatment, except 5'-nucleotidase which specific activity decreases in liver after hydrocortisone treatment.     

Effects of prolonged guanidinoethanesulphonate administration on taurine and other amino acids in rat tissues

In order to deplete tissue taurine, 2-guanidinoethanesulphonate, a structural analogue of taurine was administered in drinking water with taurine-free diet to adult rats for four weeks. As a consequence the taurine concentrations in the blood serum, liver, kidney, spleen, intestine, lung, heart, muscle and cerebellum fell by nearly one half. Threonine, serine, glycine, alanine, methionine, tyrosine, lysine and histidine concentrations increased in blood plasma. Similar changes were also discernible in the heart and muscle. In the kidney and the lung the concentrations of several other amino acids fell as well, though increments occurred in the threonine content in the kidney and in threonine, serine and methionine contents in the lung. Taurine was practically the only amino acid the level of which fell in the liver, spleen, intestine and cerebellum. These findings indicate that 2-guanidinoethanesulphonate combined with taurine-free diet effectively lowers tissue taurine levels, but its action is not specific to taurine. It may be used as a tool to elucidate the physiological functions of taurine in the body.     

Effect of corticotropin and hydrocortisone on the Ca2+-ATPase activity of skeletal muscle sarcoplasmic reticulum

The effect of corticotropin (ACTH1-39), synacthen (ACTH1-24) and hydrocortisone-hemisuccinate on the activity of Ca-ATPase of skeletal muscle sarcoplasmic reticulum (SR) and calcium (Ca) accumulation in SR vesicles has been studied. It has been shown that ACTH1-39 (I U per 100 g body weight) increased the activity of Ca-ATPase in skeletal muscle SR of rats, while hydrocortisone (5 mg per 100 g body weight) did not change the activity of Ca-ATPase in skeletal muscle SR. However, both hormones increase the total activity of ATPase. ACTH1-39 and ACTH1-24 (0.05-0.0005 U/ml) and hydrocortisone (2.8 X 10(-7)-2.8 X 10(-9) mol/l) increased in vitro Ca-ATPase isolated from rabbit skeletal muscle SR and accumulation of Ca is SR vesicles. At the same time, hydrocortisone reduced calcium/phosphorus ratio, while ACTH1-39 and ACTH1-24 increased it, i.e. hydrocortisone facilitated Ca accumulation in SR requiring more ATP energy, whereas ACTH facilitated Ca accumulation in SR requiring less ATP energy.