Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

L-tryptophan (L-TRP), the competing amino acids (CAA) valine and leucine and the cortisol levels taken at 8 a.m. after administration of dexamethasone on the previous day, were determined in 160 patients suffering from depression. The ratio between the L-TRP values and the sum of the competing amino acids was calculated. The clinical relevance of the L-TRP/CAA ratio in the case of major depression (DSM-III) versus minor depression (dysthymic disorder, atypical depression and adaptation disorder with depressive mood) was studied in comparison with the DST. Patients suffering from major depression showed a significantly decreased (p = 0.0006) L-TRP/CAA ratio. The combination of a decreased L-TRP/CAA ratio (cut off point less than or equal to 0.130) or an abnormal DST (cut off point greater than or equal to 3.5 micrograms/dl) is the best criterion which allows 59.0% of the patients suffering from major depression to be identified correctly with a specificity of 90.9%; the above-mentioned criterion permits 70.0% of the patients to be classified correctly into their actual group.
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PMID:The diagnostic performance of the L-tryptophan/competing amino acids ratio in major depression. 375 49

The score on the Hamilton Depression Rating Scale (HDRS), the L-tryptophan:competing amino acid (valine + leucine) (L-TRP:CAA) ratio, and the 3-methoxy-4-hydroxyphenylglycol (MHPG) flow in 24-hr urine were recorded in 83 depressed patients undergoing a Dexamethasone Suppression Test (DST). The subjects were diagnostically subdivided according to DSM-III into minor depression (296.82, 300.40, 309.00), major depression without melancholia (296.X2), with melancholia (296.X3), or with psychotic features (296.X4). Minor depression, major depression with melancholia, and major depression with psychotic features can be regarded as distinct biological entities. Major depression without melancholia is a heterogeneous group with reference to the biological markers. By combining these biological data with age in a discriminant function analysis, 81.9% of all depressed patients can be correctly classified into minor or major depression groups. The combined biological markers can also be used to predict the severity of the depression; 42.5% of the variance in the HDRS score is accounted for by multiple regression on the biological figures. Multivariate statistical techniques considerably improve prediction for both subtype and severity of depression.
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PMID:Prediction of subtype and severity of depression by means of dexamethasone suppression test, L-tryptophan: competing amino acid ratio, and MHPG flow. 381 68

Ultraviolet-irradiated Escherichia coli K12 uvrA(B,C) cells show higher survival if plated on minimal growth medium (MM) rather than on rich growth medium (RM). This phenomenon has been referred to as 'minimal medium recovery' (MMR). UV-irradiated (4 J/m2) uvrA cells showed a similar rate of protein synthesis, whether incubated in MM or RM, however, they showed a severe depression in DNA synthesis when incubated in MM that lasted for about 30 min, and the normal rate of DNA synthesis was not reestablished until about 60 min after irradiation. When a sample of these same cells was switched to RM immediately after UV-irradiation, there was only a slight slowing of DNA synthesis, and the normal rate of synthesis was reestablished by 60 min. An additional mmrA mutation or growth retardation by valine blocked both this extra DNA synthesis in RM, and the inhibitory effect of RM on survival. These findings suggest that the absence of a marked delay in DNA synthesis observed in RM may be responsible for the inhibitory effect of RM on the survival of UV-irradiated excision-deficient cells. Two hypotheses, which are not mutually exclusive, are proposed and supported by data to explain why a fast rate of DNA synthesis after UV-irradiation partially inhibits postreplication repair and enhances cell lethality.
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PMID:A mechanism for rich-medium inhibition of the repair of daughter-strand gaps in the deoxyribonucleic acid of UV-irradiated Escherichia coli K12 uvrA. 389 44

After surgical placement of end-to-side portacaval shunts (PCS), 4 adult mongrel dogs (11.8 to 18.2 kg) were fed purified diets and monitored for approximately 50 weeks for changes in body weight, neurologic status, and an array of clinically important biochemical variables. Two healthy dogs, fed the same diets and maintained in the same environment, were also observed (controls). Body weights were relatively stable over the period of observation. The branched-chain ratio ([valine] + [leucine] + [isoleucine]/[phenylalanine] + [tyrosine]), an index of the degree of change in plasma amino acid concentrations, was significantly lower in dogs with PCS than in controls. Despite this depression in branched-chain ratio, the principals (dogs with PCS) were essentially free of neurologic symptoms. Statistically significant decreases due to portacaval shunting were seen in the serum concentrations of glucose, calcium, urea nitrogen, creatinine, cholesterol, and albumin. Total protein, globulin, and triglyceride concentrations tended to be lower in the serum of principals than in serum of controls, but the differences were not statistically significant. Statistically significant increases due to portacaval shunting were seen in plasma concentrations of total conjugated bile acids and sulfobromophthalein retention. Concentrations of the following compounds tended to be higher in serum of principals than in serum of controls: phosphorus, chloride, uric acid, total bilirubin, lactate dehydrogenase, aspartate transaminase, alanine transaminase, and alkaline phosphatase. Liver biopsy at 7 months after operation showed mild-to-extensive atrophy of hepatocytes, mild-to-extensive fibrosis, and collapsed portal veins in all principals examined.
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PMID:Long-term biochemical and physiologic effects of surgically placed portacaval shunts in dogs. 395 18

1. When applied directly to the brain, angiotensin II amide, as either the valine(5) octapeptide, causes rats in normal fluid balance to drink water.2. The drinking response to angiotensin injections is copious, rapid, repeatable within the same test session, and stable over months of testing in the same animal.3. The response is motivationally potent and specific. After injection the animals move directly to the source of water and drink. There is typically no preliminary hyperactivity or subsequent depression. The animals do not eat, gnaw or exhibit other behaviours that are not normally seen during spontaneous drinking. The injections rouse sleeping animals to drink and interrupt eating in animals deprived of food for two days.4. The region of the brain that is most sensitive to angiotensin includes the anterior hypothalamus, the preoptic region, and the septum including the nucleus accumbens.5. Intracranial renin elicited drinking. Bradykinin and vasopressin did not, nor did adrenaline, noradrenaline or aldosterone. In the most sensitive region, sites positive for angiotensin also yielded drinking to carbachol.6. Responses were obtained with 5 ng (ca. 5 p-mole) and occurred reliably with 50 ng angiotensin or more. The dose-response curve for amount drunk rose from 5 to 100 ng and levelled off thereafter. Angiotensin is therefore the most potent dipsogen known and is effective at doses that are reasonably within the concentration range for circulating endogenous angiotensin.7. Injections into the sensitive region of doses of angiotensin that were effective for drinking did not produce peripheral haemodynamic changes in lightly anaesthetized rats.8. This work strengthens the suggestion that angiotensin is a natural hormone of drinking behaviour that participates in extracellular thirst by its release from the kidney and subsequent direct action on a specific chemoreceptive region in the anterior diencephalon and limbic lobe.
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PMID:Drinking induced by injection of angiotensin into the rain of the rat. 432 23

Mice were fed diets deficient in a single essential amino acid, and the primary immune responses to inoculation of allogenic tumor cells was measured by in vitro assay of cellular immunity. Moderate reduction of the amino acids phenylalanine-tyrosine, valine, threonine, methionine-cystine, isoleucine, and tryptophane in the diet produced profound depression of hemagglutinating and blocking antibody responses, although cytotoxic cell-mediated immunity remained intact. These diets had previously been shown to result in a selective depression of tumor growth in mice. Limitation of the amino acids arginine, histidine, and lysine in the diets gave rise to only slight depression of the immune responses. These diets had previously been shown to produce a proportional decrease in both tumor growth and host body weight. Moderate leucine restriction resulted in a paradoxical depression of cytotoxic cell-mediated immunity with little effect on serum blocking activity. Slight increases had previously been noted in the weight of tumors in mice fed leucine-restricted diets. Deficiency or imbalance of essential amino acids in the diet may produce profound depression of immune responses and apparent, marked changes in the immune resistance of the host animal to tumors.
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PMID:Quantitative effects of nutritional essential amino acid deficiency upon immune responses to tumors in mice. 468 18

Acute, uncontrollable stress increases norepinephrine (NE) turnover in the rat's brain (thereby depleting NE) and diminishes the animal's subsequent tendency to explore a novel environment. We determined whether supplemental dietary tyrosine could prevent some of these changes. Rats given a control diet or diets enriched with tyrosine or tyrosine plus valine were exposed to tail-shock stress or to no stress over a 60-min period. Exposure to the stress caused an increase in NE turnover, decreasing NE and increasing 3-methoxy-4-hydroxy-phenylethylene glycol sulfate (MHPG-SO4) concentrations within the locus coeruleus, hypothalamus and hippocampus. No changes were detected in serotonin (5-HT) levels or turnover. Behavioral deficits following the stress were observed using measures of locomotion and of exploration in a novel open-field environment: stressed animals displayed much less spontaneous motor activity, hole-poking or frequency of standing on their hind legs than control animals. Animals receiving the tyrosine-enriched diet displayed neither the stress-induced depletion of NE nor the behavioral depression. These preventive effects of tyrosine were abolished by co-administration of valine, a large neutral amino acid that competes with tyrosine for transport across the blood-brain barrier. Since tyrosine alone, in animals not subjected to stress, did not change NE turnover nor the behaviors studied, our observations affirm that catecholaminergic neurons respond to the precursor amino acid only when they are physiologically active. Supplementary tyrosine may be useful therapeutically in people exposed chronically to stress.
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PMID:Neurochemical and behavioral consequences of acute, uncontrollable stress: effects of dietary tyrosine. 620 15

Serum amino acid (AA) levels were determined for 18 cholecystectomy patients who had preserved and immediately utilized G-I function for absorption of 3,000 kcal/day elemental diet. Ten were given 132 gm AA/day; eight were given only 66 gm AA/day. Historical controls were 27 comparable patients who had received conventional hypocaloric intravenous (IV) regimens. Unfed patients' branched chain AAs (BCAAs) + TYR were depressed initially, then rebounded by day 3 or 4. Their glucogenic AAs were still depressed after 72 hours. Complete restoration of the basal pattern required five to ten days. Fully nourished patients maintained basal levels of all AAs on day 1. Every AA rose above basal, some with statistical significance as early as day 2. Moderately fed patients had BCAA depression, but for only 24 hours. LEU, ILE, VAL, TYR, MET, ASP, LYS, and ARG had already returned to basal levels on day 2, while the remaining AAs were much less depressed than in the unfed controls. All fed patients were discharged uneventfully 24-48 hours postcholecystectomy. The positive protein balance and elevated AA levels correlate with enhanced wound healing, host sepsis resistance, and shortened hospitalization.
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PMID:Elevation of postoperative plasma amino acid concentrations by immediate full enteral nutrition. 643 8

Five levels of L-valine [3.3 (basal), 5.5, 7.8, 10.1 and 12.4 g/d] were fed to gilts from one estrus before mating through two pregnancies and for 30 d of a third pregnancy. Five litter-mate outcome groups of five animals each were allocated randomly to the diet treatments. Animals were individually fed 1.82 kg/d premating and during pregnancy. A common diet was fed to all animals during lactation at levels of 4.0 and 4.75 kg/d for first and second farrowings, respectively. Animals fed 3.3 g/d L-valine retained less N (P less than .10) at d 45 and 90 for two pregnancies than did animals fed higher valine levels. Plasma valine concentrations determined after a 24-h fast and 2 h postfeeding increased sharply (P less than .01) among animals fed more than 5.5 g/d L-valine. There was a treatment X bleeding time interaction (P less than .01) for plasma valine, explained by a postfeeding depression compared with a higher fasting concentration for animals fed 3.3 g/d L-valine. At all other levels of valine, the fasting and postfeeding plasma valine concentrations were equal or increased after feeding. Sow weight gain during the experiment increased (linear, P less than .05) as dietary L-valine increased. Estimated milk yield was greatest for animals fed 5.5 g/d, but average pig gain was maximized at 7.8 g/d L-valine. We conclude that 5.5 g/d L-valine met the requirement for pregnancy in this experiment.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Valine requirement for reproduction in swine. 667 87

The short-term effects of feeding rats high levels of L-leucine or L-isoleucine on valine metabolism in vivo have been investigated. Consumption of a low-protein diet containing an additional 5% of leucine resulted in depression within one hour of the plasma concentrations of isoleucine, valine, alpha-keto-beta-methylvalerate, and alpha-ketoisovalerate. Concurrently with these changes in blood branched-chain amino acids and branched-chain ketoacids was a rapid increase (51%) in whole-body L-[1-14C]-valine oxidation. Studies with intragastrically administered leucine solutions indicated that the depressions in blood concentrations of valine occurred over the same time period as the stimulation in valine oxidation. In contrast, consumption of a low-protein diet containing an additional 5% of isoleucine had no significant effect on the plasma concentrations of leucine, valine, and alpha-ketoisocaproate; a significant (P less than 0.01) depression in the plasma concentration of alpha-ketoisovalerate was observed three hours after the diet containing excess isoleucine had been consumed. In contrast to the results obtained with excess leucine, consumption of excess isoleucine had no significant effect on the rate of valine oxidation in vivo. As part of an effort to explain the leucine-induced depletion of plasma valine and stimulation of valine oxidation, liver and muscle branched-chain aminotransferase and liver branched-chain ketoacid dehydrogenase activities were measured. Consumption of excess leucine had no significant effect on either muscle or liver aminotransferase activities, but was associated with a greater than two-fold increase in hepatic dehydrogenase activity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Valine metabolism in vivo: effects of high dietary levels of leucine and isoleucine. 672 55


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