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Results 701 - 750 of 1216
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Walter G A - - 1988
Isocratic reverse-phase high performance liquid chromatography techniques were developed to resolve and quantitate the purine nucleosides adenosine (Ado) and inosine (Ino) and their metabolites hypoxanthine (Hyp), xanthine (Xan), and uric acid (UA) in the cerebrospinal fluid of the rat. The moving phase composition for resolving hypoxanthine, xanthine and uric acid ...
Färkkilä M - - 1988
For assessment of the underlying central mechanisms of interferon (IFN), measurements have been made of the neurotoxicity, cerebrospinal fluid (CSF) 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) concentrations, along with electroencephalographic (EEG) recordings and visual evoked potentials (VEP) during recombinant IFN-gamma therapy. Interferon-gamma was administered intravenously to 14 patients with ...
Garreau B - - 1988
Anomalies in dopamine metabolism were investigated by assaying total homovanillic acid, and its free and conjugated fractions, in the urine of 34 autistic, 34 normal and 34 mentally retarded children. An increase in total homovanillic acid in autistic and retarded children is apparently due to an increase of free homovanillic ...
Murai S - - 1988
A rapid and simple chromatographic procedure using HPLC with electrochemical detection is described for simultaneous determination of the substrates from precursor amino acids to metabolites related to synthesis and metabolism of three monoamine neurotransmitters--norepinephrine (NE), dopamine (DA), and 5-hydroxytryptamine (5-HT, serotonin)--in discrete brain areas of the mouse. Under the present ...
Perry T L - - 1988
We measured concentrations of 3-methoxy-4-hydroxy-phenylglycol, 3,4-dihydroxyphenylacetic acid, homovanillic acid, and 5-hydroxyindoleacetic acid--the metabolites of noradrenaline, dopamine, and serotonin used as central neurotransmitters--in the cerebrospinal fluid (CSF) specimens of five girls with Rett syndrome. These patients met the clinical criteria for both inclusion and exclusion of the diagnosis of Rett syndrome. ...
Shimoyama M - - 1988
The effect of a xanthine derivative, 3-methyl-1-(5-oxohexyl)-7-propylxanthine (HWA 285, 10 mg/kg i.p.), on the release of endogenous monoamines and their metabolites from the rat striatum and hippocampus are examined in vivo by intracerebral dialysis technique. Using this method, which is based on the dialysis principle, a small-calibered (0.5 mm) dialysis ...
Bolger G T - - 1988
The regional concentrations of dopamine, serotonin, dihydroxyphenylacetic acid, homovanillic acid and 5-hydroxyindole acetic acid were measured in mouse brain following administration of the dihydropyridine calcium channel activator BAY K 8644, and antagonist, nifedipine. BAY K 8644 (1-8 mg/kg) produced dose- and time-dependent increases in dihydroxyphenylacetic acid, homovanillic acid and 5-hydroxyindoleacetic ...
Kornhuber J - - 1988
The concentration of 19 amino acids and ethanolamine in two independent groups (n = 36, n = 19) of normal human cerebrospinal fluid (CSF) samples were measured by high performance liquid chromatography. Age, sex, time of lumbar puncture, position during lumbar puncture, protein and glucose content of the CSF were ...
Manyam B V - - 1988
Employing a triple-column ion-exchange/fluorometric procedure, 29 amino compounds, including amino acid neurotransmitters, were measured in lumbar cerebrospinal fluid (CSF) from two groups of patients with idiopathic Parkinson's disease de novo (n = 6) and those who were treated with carbidopa/levodopa (n = 6), and from neurologically normal controls (n = ...
Scheuermann D W - - 1988
To demonstrate the intracellular store of 5-hydroxytryptamine and dopamine in pulmonary neuroepithelial bodies of the neonatal rabbit after treatment with the corresponding amino-acid precursors L-5-hydroxytryptophan or L-3,4-dihydroxyphenylalanine, formaldehyde-induced fluorescence in combination with microspectrofluorimetric analysis has been used. Emission spectra and excitation spectra in an extended wavelength range from 240 to ...
Mihatsch W W Department of Neurology, University of Würzburg, Federal Republic of - - 1988
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) destroys nigrostriatal dopaminergic pathways and thereby produces a syndrome similar to Parkinson's disease. MPTP is oxidized by monoamine oxidase B (MAO B) to the 1-methyl-4-phenylpyridinium ion (MPP+), which is taken up in dopaminergic neurons through the dopamine (DA) uptake system, where it develops its toxic effect. Our observations ...
Hagenfeldt L - - 1988
The concentrations of amino acids in the cerebrospinal fluid (CSF) were measured in pairs of healthy mono- and dizygotic twins. Intraclass correlations were calculated. Genetic and cultural heritabilities were estimated using a path analytical model. CSF levels of glycine, tyrosine and arginine were shown to be influenced by genetic factors. ...
Linnoila M - - 1988
This short review examines recent findings on neurochemical differences between alcoholics and various control populations. Particular emphasis is given to clinical variables which affect concentrations of neurotransmitter metabolites in the cerebrospinal fluid, and which have to be controlled in order to make meaningful comparisons between various diagnostic groups. The review ...
Doherty J D - - 1988
1. Type I (permethrin and allethrin) or type II (cypermethrin and fenvalerate) pyrethroids caused 23-37% increases in the striatal content of the dopamine metabolite 3,4-dihydroxyphenylacetic acid (DOPAC). 2. Toxicity symptoms and increases in DOPAC were associated with higher brain concentrations for type I (2.6-5.8 micrograms/gm) than type II pyrethroids (0.4-0.6 ...
Telford N - - 1988
The effects of aging and estradiol on the three major hypothalamic monoaminergic systems were measured in female C57BL/6J mice. Both aging and estradiol treatment induced small (10-15%) changes in the levels and ratios of the monoamines and their catabolites. In addition, the levels of 5-hydroxyindoleacetic acid, the major serotonergic catabolite, ...
Harkness R A - - 1988
Concentrations of amino and organic acids, phosphate, sulphate, gluconic acid and gluconolactone were measured in amniotic fluid samples which contained either normal or raised hypoxanthine concentrations. In this way, the effect of mild fetal ATP depletion could be determined. The effects of this mild asphyxia were to raise concentrations of ...
Sato H - - 1988
To test the scavenging of reactive oxygen species (ROS), we added synovial fluids from patients with rheumatoid arthritis (RA) and osteoarthritis, as well as hyaluronic acid (HA) and its 2 subcomponents, D-glucuronic acid and N-acetyl-D-glucosamine, to 2 ROS-generating systems, activated neutrophils and xanthine-xanthine oxidase. Synovial fluid from RA patients, HA, ...
Beni M - - 1988
By use of a simple anticonflict procedure (Vogel test), it was demonstrated that L-pyroglutamic acid (L-pyrrolidone carboxylic acid [L-PCA]), an amino acid naturally occurring in mammalian tissues and fluids, possesses anxiolytic activity. This tissues and fluids, possesses anxiolytic activity. This effect was stereospecific (D-PCA was inactive) and, in the rat, ...
Just M - - 1988
Multislice SE- or IR-sequences with different TR- and T1-times, respectively, are often used, to determine T1- and T2-values for tissue characterisation. To investigate the perturbating influence of the sequential excitation in multislice technique, we measured the signal intensities and calculated the T1-values of phantoms as a function of gap widths ...
Meier D H - - 1988
The concentrations of 23 amino acids (AA) were measured in CSF of patients with Amyotrophic Lateral Sclerosis (ALS). A micro-method with picomole sensitivity was used. Compared with healthy controls no significant alterations of single or total AA concentrations were found. These results contrast with data published in a previous study ...
Johnston C A - - 1987
1. The effects of radiofrequency lesions of the ventral noradrenergic bundle (VNB) on monoamine and metabolite concentrations in several discrete areas of the rat hypothalamus were examined. Monoamines and metabolites were analyzed utilizing high-performance liquid chromatography coupled with electrochemical detection. 2. VNB lesions decreased the concentrations of norepinephrine (NE) and ...
Decazes J M - - 1987
Patients with purulent meningitis received amoxicillin-clavulanic acid (200/20 mg/kg [body weight] per day). Clavulanic acid levels in cerebrospinal fluid were less than or equal to 0.05 micrograms/ml in 5 of 18 samples and ranged from 0.1 to 0.8 micrograms/ml in the others. Of 12 cerebrospinal fluid samples tested, 10 lacked ...
Davidson M - - 1987
Plasma levels of the dopamine metabolite homovanillic acid (pHVA) may potentially reflect upon central dopamine activity. This study examines the effects of debrisoquin, haloperidol, and the two drugs combined on pHVA concentrations of schizophrenic patients. Debrisoquin is a drug that suppresses the peripheral formation of homovanillic acid without affecting the ...
Romero R - - 1987
This study was undertaken to examine whether spontaneous labor at term is associated with changes in the amniotic fluid concentrations of arachidonate lipoxygenase metabolites. Amniotic fluid was obtained from 15 women at term in active labor (with cervical dilatation of at least 6 cm) and from 15 nonlaboring control women ...
Reader T A - - 1987
The catecholamines noradrenaline (NA), dopamine (DA), adrenaline (AD), the indoleamine 5-hydroxytryptamine (5-HT; serotonin), as well as some of their major metabolites were assayed by high-performance liquid chromatography (HPLC) with electrochemical detection, in four well-defined areas of the rat cerebral cortex: anterior cingulate (CIN;Cg1 and Cg3), piriform and entorhinal (PiEn), hind-limb ...
Dluzen D E - - 1987
In vivo release of dopamine (DA) and its metabolites were determined following a direct infusion of 3,4-dihydroxyphenylalanine (L-DOPA) through a push-pull cannula in the caudate nucleus of unanesthetized, freely behaving rats. L-DOPA infusions increased the release of DA and dihydroxyphenylacetic acid (DOPAC) beginning with 10(-5) M L-DOPA, while homovanillic acid ...
Dillen L - - 1987
The technique of isotope dilution mass spectrometry has been used for the measurement of biogenic amine metabolites in cerebrospinal fluid (CSF). CSF samples were collected from rabbits treated with alpha 2-antagonists. The aim of our study was to determine the specificity of these drugs on the central nervous noradrenergic, dopaminergic ...
Igari T - - 1987
Tryptophan, its metabolites and related enzyme activity in synovial fluid, blood and urine in patients with rheumatoid arthritis (RA) and osteoarthritis (OA) were measured. The levels of tryptophan, kynurenine and anthranilic acid in the synovial fluid higher in RA were than in OA, whereas the xanthurenic acid level was equal ...
Oliw E H - - 1987
Human seminal fluid was recently found to contain 18,19-dehydroprostaglandins E1 and E2 (E. H. Oliw, H. Sprecher, and M. Hamberg, (1986) J. Biol. Chem. 261, 2675-2683). In the present study, the cis and trans isomers of 18,19-dehydroprostaglandins E1 and E2 were prepared by incubation of microsomes of ram vesicular glands ...
Lehnert H - - 1987
Brain serotoninergic neurons are known to participate in cardiovascular regulation. Administration of the serotonin precursor 5-l-hydroxytryptophan in conjunction with the monamine oxidase inhibitor phenelzine and the selective peripheral l-amino acid decarboxylase inhibitor carbidopa has been shown to raise the repetitive extrasystole threshold in the canine heart. The present investigation demonstrates ...
Goldsmith R F - - 1987
The reversed-phase liquid-chromatographic system described here is capable of resolving the neurotransmitter amino acids aspartic acid, glutamic acid, and gamma-aminobutyric acid (GABA) plus 21 other amino acids in cerebrospinal fluid (CSF) in a single analysis. The amino acids, derivatized with o-phthalaldehyde, are separated in 65 min. Concentrations of glutamine less ...
Kok R M - - 1987
A sensitive and accurate stable isotope dilution assay was developed for the measurement of pipecolic acid in body fluids using electron capture negative ion mass fragmentography. The method utilizes [2H11]pipecolic acid as the internal standard. Sample preparation consisted of derivatization in aqueous solution (pH 11.5) of the amine moiety with ...
Kim C S - - 1987
2,4,5-Trichlorophenoxyacetic acid (2,4,5-T) reduced the uptake of 5-hydroxy-3-indoleacetic acid (5-HIAA) by the choroid plexus in a dose-related manner, while treatment with quinolinic acid at comparable concentrations did not inhibit 5-HIAA uptake. The role of carrier-mediated transport in the clearance of 5-HIAA from cerebrospinal fluid (CSF) was also evaluated in vivo ...
Nissbrandt H - - 1987
Measurements of the turnover of dopamine (DA) and DA metabolites have been performed in the striatum and substantia nigra (SN) of the rat. Turnover rates of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid have been assessed from the disappearance rates after blocking their formation by inhibition of monoamine oxidase by pargyline ...
Moffett R B - - 1987
Angiotensinogen (Aogen) (CA 11002-13-14), the prohormone of the neuro- and vasoactive peptide angiotensin II (Ang II) (CA 11128-99-7), is found in dog brain as well as in dog plasma. At 2-4 micrograms/ml CSF, Aogen comprises 1-2% of the total protein in dog CSF. Immunopurified CSF and plasma Aogen were compared ...
Miller A L - - 1987
Prior studies have shown that homovanillic acid is the principal metabolite of dopamine in the primate central nervous system (CNS). In studies of primates given deuterated homovanillic acid systemically, however, only 50% of the administered amounts have been recovered in the urine over the next 4-48 hr. These findings have ...
Coudray-Lucas C - - 1987
1. Soman induced a decrease in hypothalamic, hippocampal and cortical noradrenaline, an increase in hippocampal and cortical dopamine and an increase in hypothalamic serotonin while paraoxon did not modify these neurotransmitter concentrations. The increases in 3,4-dihydroxyphenylacetic acid, homovanillic acid and 5-hydroxyindole acetic acid produced by the two drugs witness an ...
Syrogiannopoulos G A - - 1987
The pharmacokinetics and bacteriological efficacy of ticarcillin and clavulanic acid administered individually or in combination were assessed in rabbits with experimental Escherichia coli K-1 and Haemophilus influenzae type b meningitis. The mean penetrations into the cerebrospinal fluid (CSF) of infected animals after a single dose of ticarcillin-clavulanic acid were approximately ...
Scheinin H - - 1987
The kinetics of monoamine metabolites, 3-methoxy-4-hydroxyphenylglycol (MHPG), 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA), in cisternal CSF were determined after monoamine oxidase (MAO) inhibition (pargyline, 100 mg/kg) and tyrosine hydroxylase inhibition (alpha-methyl-p-tyrosine, alpha-MPT, 250 mg/kg) in awake rats. In addition, the possibility of a peripheral contribution to CSF MHPG levels ...
Airaksinen E M - - 1987
Taltrimide (2-phthalimidoethanesulphon-N-isopropylamide), a lipophilic derivative of taurine and a potent anticonvulsant in animal studies, was administered in daily doses of 1 and 2 g for 2 weeks with an interval of 2.5 months in 2 phase I clinical trials to 9 drug-resistant epileptic patients. Seizures and EEG were recorded, and ...
Downer R G - - 1987
High performance liquid chromatography with coulometric electrochemical detection has been used to achieve simultaneous determination of norepinephrine, epinephrine, 5-hydroxytryptophan, normetanephrine, dopamine, metanephrine, 3,4-dihydroxyphenylacetic acid, N-acetyldopamine, tyramine, tryptophan, 5-hydroxyindoleacetic acid, 5-hydroxytryptamine, N-acetyl-5-hydroxytryptamine, homovanillic acid, tyrosine, p-octopamine, N-acetyl-p-octopamine, and p-synephrine. The procedure has been applied to study monoamine degradation in the insect ...
Toraya T - - 1987
Simultaneous addition of an aliquot of body fluid obtained from the surf clam, Spisula solidissima, enhanced oocyte germinal vesicle breakdown induced with serotonin but not with KCl. When the body fluid and serotonin were added sequentially to the oocytes, potentiation did not occur. Body fluids of both males and females ...
Garnett E S - - 1987
The local concentration of 6-[18F]fluoro-L-dopa(18F) reflects the activity of aromatic acid decarboxylase (AADC), the enzyme that generates dopamine from its precursor amino acid, L-dopa. In young healthy adults, the local concentration of 18F, and hence AADC activity, is constant in coronal slices taken in a rostrocaudal direction. With increasing age ...
Javaheri S - - 1987
The purpose of these experiments was to study the effects of acetazolamide, a carbonic anhydrase inhibitor, on cisternal cerebrospinal fluid (CSF) ions during normal acid-base balance. We measured blood and CSF acid-base variables in two groups (n = 6 in each) of anesthetized, paralyzed and mechanically ventilated dogs with bilateral ...
Heikkila R E - - 1987
The MPTP-treated mouse has proven to be a valuable model of parkinsonism. For example, C57 black mice treated with MPTP exhibit a large decrement in the neostriatal content of dopamine and its metabolites, a marked reduction in the capacity of neostriatal synaptosomal preparations to accumulate [3H]dopamine, a large decrease in ...
French G L - - 1987
Tuberculostearic acid, a structural component of Mycobacterium tuberculosis, was identified by gas chromatography/mass spectrometry with selected ion monitoring in cerebrospinal fluid (CSF) from 13 patients with proven and 8 out of 9 patients with suspected tuberculous meningitis; the negative result was in a patient whose symptoms and CSF abnormalities may ...
Veinot J P - - 1987
We reevaluated the effects of unilateral sensorimotor cortex ablation on dopamine and dihydroxyphenylacetic acid concentration in the left and right neostriatum. We found no evidence for an asymmetry of either dopamine or dihydroxyphenylacetic acid in control or sham-operated animals and cortical ablation had no effect on dopamine or dihydroxyphenylacetic acid ...
Guan X M - - 1987
The in vivo efflux of endogenous 3,4-dihydroxyphenylethylamine (DA 5-hydroxytryptamine (5-HT), 3,4-dihydroxyphenyl-acetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxy-indoleacetic acid (5-HIAA) in the nucleus accumbens of the anesthetized rat was studied using a push-pull cannula. Local perfusion for 10 minutes with 35 mM K+ significantly (P less than 0.01) increased the ...
Jolkkonen J - - 1987
The effect of desglycinamide-arginine-vasopressin (DGAVP) on monoaminergic neurotransmission was studied in human subjects. Samples of cerebrospinal fluid (CSF) were collected during 240 min after DGAVP (2 mg) had been administered intranasally, and monoamine metabolites in CSF were measured with HPLC using electrochemical detection. Levels of homovanillic acid and 5-hydroxyindoleacetic acid ...
Dillen L - - 1987
The alpha 2-antagonist idazoxan was administered intravenously to rabbits. The increase in central noradrenergic, dopaminergic and serotonergic activity was followed as a function of time by determining neuronal parameters in the cerebrospinal fluid (CSF) and was compared with changes previously determined after yohimbine. These parameters include the enzyme dopamine-beta-hydroxylase (D ...
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