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Query: UMLS:C0011570 (
depression
)
172,036
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In this study, the factors in overnight dwell fluid (8 to 10 hr dwell) depressing granulocyte (GC)
NAD
(P)H-oxidase dependent radical species production are characterized. At present, most studies have essentially focused on fresh, unspent dialysate and on peritoneal macrophages. The response to Staphylococcus aureus (Staph A) was dose-dependently depressed for both GC CO2 production (from 91.3 +/- 8.4 to 9.0 +/- 1.5 dpm/10(3) GC, P < 0.01) and chemiluminescence (CL) (peak from 7.3 +/- 0.8 to 1.6 +/- 0.8 cps x 10(3)/GC, P < 0.01). Stimulation with formyl-methionine-leucine-phenylalanine (f-MLP), phorbol myristic acid (PMA), Staphylococcus epidermidis (Staph Epi), E. coli, latex and zymosan revealed a parallel
depression
, pointing to an intrinsic metabolic defect, rather than failure of particle ingestion. The addition of glucose to the normal cell medium to obtain the same concentration as in the CAPD effluent (2.9 +/- 0.3 mg/dl) depressed function but not to the same extent as the genuine PD effluent. Opsonization of Staph A and E. coli induced a partial correction. No effect of pH or osmolality was observed. HPLC fractionation of CAPD effluent on a polarity based gradient revealed an elution of depressive factors in hydrophobic fractions with a nadir in F7 and F12. Analysis of the elution pattern of various uremic solutes revealed elution in F12 of p-cresol, a solute with known inhibitory effect on GC function. These events may be related to recent peritonitis (CL in response to Staph A 0.3 +/- 0.1 in effluent of 6 patients with recent peritonitis versus 2.6 +/- 0.8 cps x 10(3)/GC in 12 patients without recent peritonitis (P < 0.01). We conclude that the GC response is depressed in the presence of CAPD effluent due to excess glucose, lack of opsonization, and uremic solutes of which p-cresol is one of the responsible compounds.
...
PMID:Disturbed host defense in peritoneal cavity during CAPD: characterization of responsible factors in dwell fluid. 884 Feb 97
High morbidity and mortality in surgical management for patients with obstructive jaundice was greatly attributed to the metabolic derangements in jaundiced liver mitochondria. Isolated liver mitochondria from jaundiced rat, produced by common bile duct ligation, were used to study the relationship among NADH level, oxygen consumption, and extramitochondrial calcium concentration. Alterations in NADH percentage and oxygen consumption were accomplished by incubating mitochondria with different substrates and monitoring oxygen consumption and
NAD
(P)H fluorescence simultaneously. In jaundiced liver mitochondria with glutamate + malate as substrate, respiration increased after the addition of exogenous Ca2+ at concentrations of 1 x 10(-7), 5 x 10(-7), and 1 x 10(-6) M. The maximal effect occurred at 5 x 10(-7) M. With different NADH-related substrates, the
NAD
(P)H fluorescence measurements (X axis) correlated linearly with state 3 respiration (Y axis), the slopes of the correlation curves being 2.27 and 0.79 in control and jaundiced mitochondria, respectively. After the addition of 5 x 10(-7) M Ca2+, the respirations of both control and jaundiced mitochondria increased and the slope for jaundiced mitochondria rose to 1.67. The matrix free Ca2+ concentration in jaundiced mitochondria, measured by fluo-3 loading, was higher than that in controls (162.1 +/- 16.7 nM, vs 129.7 +/- 12.6 nM, P < 0.01), while the matrix free/total Ca2+ ratio decreased from 34.9 +/- 6.0 (x10(-6)) to 27.2 +/- 4.4 (x10(-6), 9- < 0.05. The amplitude of the change in
NAD
(P)H fluorescence was reduced in jaundiced rat liver mitochondria and this correlated with the
depression
of respiration. A decrease in free/total Ca2+ ratio may be closely related to mitochondrial respiratory impairment in jaundice.
...
PMID:Restricted redox oscillation in oxidative phosphorylation in jaundiced rat liver mitochondria and its relation to calcium ion. 902 18
46 patients with infectious-and-allergic myocarditis (IAM) and 46 patients with myocarditic cardiosclerosis (MCS) were studied for cytochemical parameters of blood lymphocyte bioenergetics. In IAM, cellular metabolism was found out to be disturbed, with the activity of G-6-PDG in spontaneous NST-test being risen against the background of
depression
of
NAD
- and NADP-diaphorases, lowering of the endogenous cytochrome "C" content and activity of alpha-GPDG. One third of IAM patients demonstrated protracted variant of the disease course by a study into the bioenergetic status of blood lymphocytes. Examination of parameters of blood lymphocytes energy exchange permits establishing more differential and diagnostic criteria for inflammatory lesion of the myocardium.
...
PMID:[The bioenergetics system of the blood lymphocytes in infectious-allergic myocarditis]. 907 68
The effect of mild closed head trauma, induced by the weight-drop method (450 g from a 1-m height), on lipid peroxidation and energy metabolism of brain tissue was determined at various times after cerebral injury in spontaneously breathing rats (1, 10, 30 minutes and 2, 6, 15, 24, 48, and 120 hours). Animals were continuously monitored for the evaluation of blood pressure, blood gases, heart rate, and intracranial pressure. Analysis of malondialdehyde (MDA) as an index of lipid peroxidation, ascorbic acid, high-energy phosphates, nicotinic coenzymes, oxypurines, and nucleosides was performed by high-performance liquid chromatography (HPLC) on neutralized perchloric acid extract of the whole brain. Data showed that MDA, undetectable in control, sham-operated rats, was already present within 1 minute of trauma (1.77 nmol/g wet weight; SD = 0.29) and reached maximal values by 2 hours (72.26 nmol/g w.w.; SD = 11.26), showing a progressive slow decrease thereafter. In contrast, ATP, GTP, and nicotinic coenzyme (
NAD
and NADP) concentrations showed significant reduction only by the second hour postinjury. Maximal decrease of the ATP and GTP concentrations were seen at 6 hours postinjury, whereas
NAD
and NADP concentrations showed maximum decline by 15 hours. Values recorded in mechanically ventilated rats did not differ significantly from those obtained in spontaneously breathing animals. These findings, supported by the absence of blood gas and blood pressure changes in the spontaneously breathing rats, strongly support the premise that biochemical changes (primarily lipid peroxidation) are not caused by secondary ischemic-hypoxic phenomena but rather are triggered by these forces acting on the brain at the time of impact. In addition, these results suggest that
depression
of energy metabolism might be caused by peroxidation of the mitochondrial membrane with a consequent alteration of the main mitochondrial function-that is, the energy supply.
...
PMID:Changes of cerebral energy metabolism and lipid peroxidation in rats leading to mitochondrial dysfunction after diffuse brain injury. 1054 99
We examined the influence of two K(ATP) channel openers, diazoxide and an analog (NNC 55-0118), on experimental beta-cell damage induced by streptozotocin (STZ; 0.5 mmol/l). Rat pancreatic islets were exposed to diazoxide or NNC 55-0118 for 30 min and were further incubated for 30 min after the addition of STZ. The islets were then washed and cultured for 24 h. Islets exposed to STZ alone showed extensive morphological damage, reduced glucose oxidation, low insulin content, and severely impaired glucose-stimulated insulin secretion and proinsulin biosynthesis. Islets treated with STZ in the presence of the channel openers (0.03-0.30 mmol/l) showed dose-dependent preservation of the morphology and improved glucose oxidation rates, insulin content, and secretion. NNC 55-0118 was capable of fully counteracting the STZ impairment, whereas diazoxide had a less protective effect. NNC 55-0118 did not counteract STZ-induced
depression
of islet
NAD
levels when examined 2 h after STZ exposure, which suggests that the mechanism of action by NNC 55-0118 is not through an inhibition of poly(ADP-ribose) polymerase. The results illustrate that K(ATP) channel openers can protect insulin-producing cells against toxic damage, an effect that may be of use in subjects with ongoing insulitis.
...
PMID:K(ATP) channel openers protect rat islets against the toxic effect of streptozotocin. 1090 69
Positron-emission tomography (PET) provides potential in neuropsychiatric drug development by expanding knowledge of drug action in the living human brain and reducing time consumption and costs. The 5-hydroxytryptamine(1A) (5-HT(1A)) receptor is of central interest as a target for the treatment of anxiety,
depression
, and schizophrenia. Research on the clinical significance of the 5-HT(1A) receptor now benefits from the highly selective radioligand [carbonyl-(11)C]WAY-100635 (WAY) for quantitative determination of 5-HT(1A) receptors in the primate and human brain in vivo using PET. In this paper, three studies are reviewed to demonstrate the suitability of WAY as radioligand for quantification of central 5-HT(1A) receptors in brain and as an applicable tool for drug development. In the first study a monkey model was used to characterize WAY binding. It was confirmed that the reference ligand 8-OH-DPAT and psychoactive drugs such as buspirone and pindolol occupies 5-HT(1A) receptors in the primate brain. Pindolol is an beta-adrenoreceptor antagonist with a high affinity to 5-HT(1A) receptors. This drug has been suggested in combination with selective serotonin reuptake inhibitors for the treatment of
depression
and was given to healthy males in the second study. Pindolol induced a marked inhibition of central 5-HT(1A) receptors as calculated by the ratio-analysis method and simplified reference tissue model, 2 h after administration of 10 mg as a single oral dose. This observation suggests that pindolol may have a role for the suggested potentiation of selective serotonin reuptake inhibitor treatment of
depression
. The third study was on robalzotan (
NAD
-299), a recently developed 5-HT(1A) receptor antagonist and putative drug with implications for the treatment of
depression
. In the cynomolgus monkey brain, robalzotan in the dose range 2-100 microg/kg IV occupied 5-HT(1A) receptors in a dose-dependent and saturable manner with a maximal calculated occupancy of 70-80%. The relationship between robalzotan plasma concentration and 5-HT(1A) receptor occupancy could be described by a hyperbolic function that was used to guide the selection of appropriate doses in man. In a subsequent PET study of robalzotan binding to 5-HT(1A) receptors in the living human brain, similar results have been replicated recently. These studies reviewed here illustrate and corroborate that quantitative neuroimaging of receptor binding has potential for the evaluation and dose finding of new central nervous system drugs.
...
PMID:Use of PET and the radioligand [carbonyl-(11)C]WAY-100635 in psychotropic drug development. 1096 60
The 5-HT1A subtype of receptors for the neurotransmitter serotonin is predominantly located in the limbic forebrain and is involved in the modulation of emotion and the function of the hypothalamus. Since 5-HT1A receptors are implicated in the pathogenesis of anxiety,
depression
, hallucinogenic behaviour, motion sickness and eating disorders, they are an important target for drug therapy. Here, we review the radioligands which are available for visualisation and quantification of this important neuroreceptor in the human brain, using positron emission tomography (PET) or single-photon emission tomography (SPET). More than 20 compounds have been labelled with carbon-11 (half-life 20 min), fluorine-18 (half-life 109.8 min) or iodine-123 (half-life 13.2 h): structural analogues of the agonist, 8-OH-DPAT, structural analogues of the antagonist, WAY 100635, and apomorphines. The most successful radioligands thus far are [carbonyl-11C] WAY-100635 (WAY), [carbonyl-11C]desmethyl-WAY-100635 (DWAY), p-[18F]MPPF and [11C]robalzotan (
NAD
-299). The high-affinity ligands WAY and DWAY produce excellent images of 5-HT1A receptor distribution in the brain (even the raphe nuclei are visualised), but they cannot be distributed to remote facilities and they probably cannot be used to measure changes in endogenous serotonin. Binding of the moderate-affinity ligands MPPF and
NAD
-299 may be more sensitive to serotonin competition and MPPF can be distributed to PET centres within a flying distance of a few hours. Future research should be directed towards: (a) improvement of the metabolic stability in primates; (b) development of a fluorinated radioligand which can be produced in large quantities and (c) production of a radioiodinated or technetium-labelled ligand for SPET.
...
PMID:Visualisation of serotonin-1A (5-HT1A) receptors in the central nervous system. 1120 45
Cyclic ADP-ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate (NAADP) are two Ca(2+) messengers derived from
NAD
and NADP, respectively. Although NAADP is a linear molecule, structurally distinct from the cyclic cADPR, it is synthesized by similar enzymes, ADP-ribosyl cyclase and its homolog, CD38. The crystal structure of the cyclase has been solved and its active site identified. These two novel nucleotides have now been shown to be involved in a wide range of cellular functions including: cell cycle regulation in Euglena, a protist; gene expression in plants; and in animal systems, from fertilization to neurotransmitter release and long-term
depression
in brain. A battery of pharmacological reagents have been developed, providing valuable tools for elucidating the physiological functions of these two novel Ca(2+) messengers. This article reviews these recent results and explores the implications of the existence of multiple Ca(2+) messengers and Ca(2+) stores in cells.
...
PMID:Physiological functions of cyclic ADP-ribose and NAADP as calcium messengers. 1126 60
Cyclosporine protects the heart against ischemia/reperfusion injury, but its effect on cardiac metabolism is largely unknown. We assessed cyclosporine-induced metabolic changes in the rat heart prior to occlusion using magnetic resonance spectroscopy (MRS) and correlated effects with infarct size in a coronary occlusion/reperfusion model. The two study groups were cyclosporine and cyclosporine + coronary occlusion (n = 20/group). Rats were pretreated with cyclosporine (5, 10, 15, and 25 mg/kg/day) or the vehicle by oral gavage for 3 days (n = 4/dose). On day 4, hearts of rats in the cyclosporine group were excised, and extracted cell metabolites were measured using (1)H and (31)P MRS. The second group was subjected to 30 min of coronary artery occlusion followed by 24 h of reperfusion. Infarct size and area at risk were measured using a double staining method. In the cyclosporine group, cyclosporine reduced cardiac energy metabolism (ATP: r = -0.89, P < 0.001) via
depression
of oxidative phosphorylation and the Krebs' cycle in a dose-dependent manner. The decrease of ATP levels was positively correlated with changes of
NAD
(+) (r = 0.89), glutamate (r = 0.95), glutamine (r = 0.84), and glucose concentrations (r = 0.92, all P < 0.002). It was inversely correlated with lactate (r = -0.93, P < 0.001). In the coronary occlusion group, cyclosporine dose dependently reduced the ratio [area of infarct/area of the left ventricle] (r = -0.86, P < 0.01), with 15 mg/kg/day being the most effective cyclosporine dose. The reduction in infarct size correlated with the reduction in oxidative phosphorylation (ATP: r = 0.97;
NAD
(+): r = 0.82, P < 0.01). The reduction in cardiac energy metabolism before occlusion may be the cause of myocardial preservation during ischemia/reperfusion.
...
PMID:Close association between the reduction in myocardial energy metabolism and infarct size: dose-response assessment of cyclosporine. 1218 71
We described the effects of nimesulide (N-[4-nitro-2-phenoxyphenyl]-methanesulfonamide) and its reduced metabolite in isolated rat hepatocytes. Nimesulide stimulated the succinate-supported state 4 respiration of mitochondria, indicating an uncoupling effect of the drug. Incubation of hepatocytes with nimesulide (0.1-1 mM) elicited a concentration- and time-dependent decrease in cell viability as assessed by lactate dehydrogenase leakage, a decrease of mitochondrial membrane potential as assessed by rhodamine 123 retention, and cell ATP
depression
. Nimesulide also decreased the levels of
NAD
(P)H and glutathione in hepatocytes, but the extent of the effects was less pronounced in relation to the energetic parameters; in addition, these effects did not imply the peroxidation of membrane lipids. The decrease in the viability of hepatocytes was prevented by fructose and, to a larger extent, by fructose plus oligomycin; it was stimulated by proadifen, a cytochrome P450 inhibitor. In contrast, the reduced metabolite of nimesulide did not present any of the effects observed for the parent drug. These results indicate that: 1) nimesulide causes injury to the isolated rat liver cells, 2) this effect is mainly mediated by impairment of ATP production by mitochondria due to uncoupling, and 3) on account of the activity of its nitro group, the parent drug by itself is the main factor responsible for its toxicity to the hepatocytes.
...
PMID:The critical role of mitochondrial energetic impairment in the toxicity of nimesulide to hepatocytes. 1238 41
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