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

Following preincubation of isolated rat liver mitochondria in the absence of substrate, the carnitine-independent oxidation of octanoate or butyrate was markedly depressed when compared to rates observed with nonpreincubated mitochondria. Carnitine addition prevented the inhibition of octanoate oxidation but not that of butyrate. 2-Tetradecylglycidic acid or Zwittergent 3-08 (Z3-08) completely blocked the effect of carnitine. Replacement of ATP in the nonpreincubated incubation system with ADP mimicked the effect of preincubation by inhibiting octanoate and butyrate oxidation. This inhibition of octanoate oxidation was also prevented by carnitine addition. There was a direct and causal relationship between the ATP/ADP ratio of the total adenine nucleotide pool and the rate of carnitine-independent octanoate oxidation in mitochondria. The depression of octanoate oxidation was associated with a decrease in the intramitochondrial AMP content and intra- and extramitochondrial ATP/ADP ratios. In a cellular system, incubating isolated hepatocytes with fructose or glycerol to lower the ATP/ADP ratio resulted in greater inhibition of octanoate oxidation by 2-tetradecylglycidic acid. The data suggest that the ATP/ADP ratio may have a role in determining the site of octanoate activation and subsequent route of oxidation.
 ...
PMID:Relationship of the ATP/ADP ratio to the site of octanoate activation. 671 56

The goal of these studies was to evaluate acute changes in protein metabolism in skeletal muscle in response to contractile activity. Rates of protein synthesis were measured by following L-[U-14C]phenylalanine incorporation into protein in muscles of the perfused rat hindlimb at rest, during 10 min of maximal isometric muscle contractions, and during 10 min of recovery. Synthesis measurements were carried out under conditions that ensured that the specific radioactivity of the tRNA-bound precursor amino acid was equal to that of extracellular phenylalanine. Protein degradation was estimated by measuring the release of Nt-methylhistidine. Rates of synthesis were markedly inhibited in response to muscle contractions in tibialis anterior, gastrocnemius, and plantaris but were unaffected in soleus. Rates of synthesis returned toward those observed in the resting condition during the recovery period. Rates of degradation were also markedly inhibited in response to muscle contractions. Decreased rates of synthesis correlated with reduced tissue contents of ATP and creatine phosphate, a reduced ATP/ADP, and an elevated tissue content of lactate. The results demonstrate that isometric contractions in muscles consisting of a high proportion of fast glycolytic fibers result in a marked depression in rates of protein synthesis that may be due to an altered energy state.
 ...
PMID:Protein synthesis versus energy state in contracting muscles of perfused rat hindlimb. 672 Aug 85

Mitochondrial oxidative phosphorylation, calcium transport activity and calcium content were investigated in dog hearts injured by excessive noradrenaline (NA). Diffuse cardiac injury was produced by a 5-hour infusion of NA (2 or 5 micrograms/kg/min), and the injury was evaluated based on ECG and hemodynamic changes. Mitochondrial calcium uptake and binding activities measured in the presence of ATP showed no significant differences between the control and NA groups. However, the calcium content of heart mitochondria isolated from the NA groups, state 3 respiration and the respiratory control index were significantly depressed without any change in the ADP/O ratio. These results suggest that excessive NA causes the intracellular calcium overload and the depression of mitochondrial respiration, and the both of these changes may play a key role in the pathogenesis of myocardial injury through the insufficient control of cytosolic calcium levels.
 ...
PMID:Effects of excessive noradrenaline on cardiac mitochondrial calcium transport and oxidative phosphorylation. 672 29

ADP and collagen-induced platelet aggregation and parameters related to the fibrinolytic system were studied in groups of healthy persons who had ingested 500 mg of diflunisal. A single dose of diflunisal resulted in a depression of platelet function in most cases. However, the effect was limited and only of clinical relevance in patients with a defective platelet function. A frequent finding was an enhanced fibrinolytic activity in plasma and saliva 2 h after ingestion of diflunisal. In approximately one-third of the cases studied, the fibrinolytic activity in saliva rose to levels that induced clot lysis within a few minutes. This could explain the clinical observation that administration of diflunisal prior to dental surgery is followed by dry socket symptoms in one-third of the patients.
 ...
PMID:Platelet function and fibrinolytic activity after a single dose of diflunisal (Donobid). 678 75

The effect of agents that change the respiratory state of the mitochondrion on tyramine oxidation was investigated. Neither uncoupler nor ADP and P1 in the presence of substrate produced any change in the rate of tyramine oxidation, as judged by direct measurement of tyramine oxidation or by H2O2 production. We conclude that previously reported depression of monoamine oxidase activity by stimulated respiration was due to oxygen depletion.
 ...
PMID:Monoamine oxidase activity of mitochondria prepared from rat liver and rat heart. 706 31

The effects of intravenous administration of 50-400 mg/kg imidazole-4-acetic acid (IMA) on the carbohydrate metabolism of the rat brain were assessed by measurement of the cerebral hemisphere contents of energy phosphates and glycolytic--citric acid cycle metabolites. IMA (100-400 mg/kg) produced a spectrum of electroencephalographic (EEG) change ranging from desynchronization to electrical suppression which was associated with unchanged tissue contents of ATP, ADP, and AMP, increasing levels of phosphocreatine, glucose, and aspartate, and decreasing levels of pyruvate, lactate, alpha-ketoglutarate, and malate. The changes in glycolytic intermediates were present within 5 min of injecting IMA (200 mg/kg) and the pattern suggested a suppression of glycolysis. The EEG stage of electrical suppression with episodic spiking (400 mg/kg) was associated with a 30% reduction of cortical high-energy phosphate use. The lowest dose of IMA (50 mg/kg) resulted in episodic EEG desynchronization which was associated with no significant changes of the measured metabolites. The results indicate that IMA is associated with metabolite changes that are compatible with a state of cerebral depression and that the desynchronous EEG pattern is without a biochemical correlate of increased neuronal activity.
 ...
PMID:The effects of imidazole-4-acetic acid on cerebral carbohydrate metabolism. 716 56

A marked depression of evoked CA1 potentials was observed with the nucleotide analogues a,b-methylene ADP (AOPCP) and adenylimido-diphosphate (AIP) and with 2'-adenosine monophosphate (2'-AMP). While the depression elicited by 5'-nucleotides was completely antagonized by the action of adenosine deaminase, AOPCP and 2'-AMP were only partially antagonized. The findings indicate that nucleotides on their own are capable of modulating synaptic transmission but that the physiologically more prevalent 5'-AMP is mediating its effect via adenosine. By producing this membrane permeable compound and allowing its re-uptake, the 5'-nucleotidase may determine the time course of purinergic action.
 ...
PMID:Effect of adenosine versus adenine nucleotides on evoked potentials in a rat hippocampal slice preparation. 726 30

Adenine dinucleotides such as beta-NAD, alpha-NAD, NADP, 3-aminopyridine adenine dinucleotide, flavin adenine dinucleotide, 3',5'-and 2',5'-adenylyladenosine mimicked the inhibitory effects of adenosine and adenine nucleotides on electrically evoked contractions of the rat and mouse isolated superfused vas deferens. The inhibitory effects were blocked by theophylline or adenosine deaminase, unaffected by the nucleotidase inhibitor alpha, beta-methylene ADP and enhanced by inhibition of adenosine deaminase. The inhibitory effects were associated with a release of purines from the vasa after preloading with [3H]adenosine. It is suggested that these compounds activate a receptor, causing the release of adenosine which is largely responsible for the inhibitions. Diadenosine pyrophosphate and triphosphate caused only depression of the vas twitch, whereas the pentaphosphate and hexaphosphate derivatives caused contraction, followed by inhibition at higher concentrations. These inhibitions were only partly reduced by theophylline or deaminase, but both contractile and inhibitory effects were enhanced by alpha, beta-methylene ADP. Noradrenaline contractions were also reduced by the higher polyphosphates. It is suggested that there may be a receptor for these dinucleotides, located at least in part postjunctionally. The pentaphosphate and hexaphosphate compounds mimicked the effects of nerve stimulation on the guinea-pig bladder, being substantially more potent than beta, gamma-methylene-ATP, and on the taenia caeci, where contraction or relaxation could be produced depending on resting tone.
 ...
PMID:Actions of adenine dinucleotides on the vas deferens, guinea-pig taenia caeci and bladder. 731 4

Rat-liver mitochondrial cholesterol ester levels were increased nine-fold and free cholesterol levels were doubled by feeding 10% lard and 2% cholesterol with Purina rabbit chow pellets to weanling male Sprague-Dawley rats for 5 weeks. This resulted in depression of State 3 (ADP-stimulated) glutamate respiration and reduced sensitivity to inhibition of phosphyorylation by tetrabutylammonium bromide and oligomycin. Brain, heart, lung, spleen, kidney and testis mitochondrial functions were not responsive to changes in dietary cholesterol nor were increases noted in free cholesterol content; mitochondrial cholesterol esters in these six tissues remained at extremely low levels regardless of treatment. Inclusion of 0.01% oleyl-p-decylbenzene sulfonate (a hypocholesterolemic agent) in the 10% lard and 2% cholesterol diet prevented elevation of rat-liver cholesterol esters and restored "normal" mitochondrial functions of respiratory control. This compound had no lowering effect on the raised level of liver mitochondrial free cholesterol nor on the reduced mitochondrial sensitivity to the phosphorylation inhibitors. We concluded that cholesterol esters were associated with depression of liver mitochondrial respiratory control and that free cholesterol was related to desensitization of mitochondria to the phosphorylation inhibitors.
 ...
PMID:Influence of dietary cholesterol on mitochondrial function in the rat. 735 95

1 The effects of single doses of naproxen and sulphinpyrazone and of 4 and 8 days treatment with sulphinpyrazone on human platelet responsiveness were compared. 2 A single dose of sulphinpyrazone had no effect whereas a single dose of naproxen caused a five-fold depression in responsiveness to collagen. 3 Repeated administration of sulphinpyrazone led to a weak and equivocal inhibitory effect on collagen-induced aggregation, second phase aggregation in response to ADP and adhesion to collagen. There was no effect on ADP-induced first phase aggregation, adrenaline-induced second phase aggregation or platelet retention in glass bead columns. 4 It is concluded that the anti-aggregant activity of sulphinpyrazone is too weak to be a major factor in its reported effect on the incidence of cardiac death.
 ...
PMID:Effect of sulphinpyrazone on human platelet aggregation, 5-hydroxytryptamine release and adhesion ex vivo: comparison with naproxen. 736 33


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>