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Anouk N A Van Der Horst-Schrivers et al.
Anticancer research, 30(12), 5153-5158 (2010-12-29)
This study aimed to determine the prevalence of excess dopamine in relation to clinical symptoms and nuclear imaging in head and neck paraganglioma (PGL) patients. Thirty-six consecutive patients with head and neck PGLs, evaluated between 1993 and 2009, were included.
Moon Chul Jung et al.
Analytical chemistry, 78(6), 1761-1768 (2006-03-16)
The photoluminescence-following electron-transfer (PFET) technique, developed in our laboratory, is a sensitive chromatographic detection method for oxidizable analytes. Because the oxidations are homogeneous, the technique avoids the problem of electrode fouling. A liquid-phase oxidant reacts with the electrochemically active analytes
Wilhelmina H A de Jong et al.
The Journal of clinical endocrinology and metabolism, 94(8), 2841-2849 (2009-07-02)
Measurements of the 3-O-methylated metabolites of catecholamines [metanephrines (MNs)] in plasma or urine are recommended for diagnosis of pheochromocytoma. It is unclear whether these tests are susceptible to dietary influences. The aim of the study was to determine the short-term
Qian Qin et al.
Journal of separation science, 38(16), 2857-2864 (2015-05-29)
The levels of catecholamines, especially dopamine, epinephrine and norepinephrine in urine and plasma have been used to assist the diagnosis and treatment of psychosis. Due to their low endogenous concentrations, the determination of the three major catecholamines is very difficult.
Marc Morissette et al.
Journal of neuroscience research, 87(7), 1634-1644 (2008-12-31)
A higher prevalence and incidence of Parkinson's disease is observed in men, and beneficial motor effects of estrogens are observed in parkinsonian women. In rodents, an effect of estradiol on dopamine systems is documented, whereas much less is known in
Aurélien Le Jacques et al.
Annales de biologie clinique, 69(5), 555-559 (2011-10-20)
Measurement of catecholamines derivatives is used to diagnose tumors such as pheochromocytomas and paragangliomas. Despite the low incidence of these diseases, their diagnosis is essential because of potentially lethal episodes of malignant hypertension related to an inappropriate secretion of catecholamines
Ju-Young Park et al.
Biological & pharmaceutical bulletin, 36(2), 252-258 (2012-12-01)
In order to measure the levels of serotonin (5-hydroxyltryptamine, 5-HT), dopamine (DA), 3,4-hydroxyphenylacetic acid (DOPAC), 3-methoxytyramine (3-MT) and homovanillic acid (HVA) simultaneously, an effective derivatization method followed by high-performance liquid chromatography (HPLC) coupled to electrochemical ionization mass spectrometry was used.
Alfredo Damasceno-Oliveira et al.
General and comparative endocrinology, 153(1-3), 385-389 (2007-06-19)
The present study evaluated the effects of cyclic variations of hydrostatic pressure (HP) on neurotransmitters in the whole brain of flounder. The concentrations of the biogenic amines L-3,4-dihydroxyphenylalanine (L-DOPA), dopamine (DA), norepinephrine (NE), epinephrine (E), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid
Rachel A Saylor et al.
Electrophoresis, 36(16), 1912-1919 (2015-05-12)
A method for the separation and detection of analytes in the dopamine metabolic pathway was developed using microchip electrophoresis with electrochemical detection. The microchip consisted of a 5 cm PDMS separation channel in a simple-t configuration. Analytes in the dopamine
Agnieszka Wąsik et al.
Pharmacological reports : PR, 64(4), 857-869 (2012-10-23)
1-Methyl-1,2,3,4-tetrahydroisoquinoline (1-MeTIQ) is present in human and mammalian brain as a racemate (R,S) of two stereoisomers: R- and S-1MeTIQ. The racemate is a mixture of the endogenous, synthesized in the brain dextrorotary R-1MeTIQ, and the exogenous, levorotary form, S-1MeTIQ. In
Graeme Eisenhofer et al.
European journal of cancer (Oxford, England : 1990), 48(11), 1739-1749 (2011-11-01)
There are currently no reliable biomarkers for malignant pheochromocytomas and paragangliomas (PPGLs). This study examined whether measurements of catecholamines and their metabolites might offer utility for this purpose. Subjects included 365 patients with PPGLs, including 105 with metastases, and a
C Viaggi et al.
Neuropharmacology, 56(8), 1075-1081 (2009-03-21)
Evidence for involvement of cytochrome P450 2E1 in the MPTP-induced mouse model of PD has been reported [Vaglini, F., Pardini, C., Viaggi, C., Bartoli, C., Dinucci, D., Corsini, G.U., 2004. Involvement of cytochrome P450 2E1 in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model
Sara Tufi et al.
Journal of chromatography. A, 1395, 79-87 (2015-04-15)
Neurotransmitters are endogenous metabolites that allow the signal transmission across neuronal synapses. Their biological role is crucial for many physiological functions and their levels can be changed by several diseases. Because of their high polarity, hydrophilic interaction liquid chromatography (HILIC)
Fredrik Pettersson et al.
Journal of medicinal chemistry, 55(7), 3242-3249 (2012-03-06)
A series of para-substituted 4-phenylpiperidines/piperazines have been synthesized and their affinity to recombinant rat cerebral cortex monoamine oxidases A (MAO A) and B (MAO B) determined. Para-substituents with low dipole moment increased the affinity to MAO A, whereas groups with
Takashi Ichinose et al.
Bioscience, biotechnology, and biochemistry, 79(9), 1542-1547 (2015-05-23)
In this study, we examined the effect of orally administrated dipeptides containing Tyr (Y) on the metabolism of catecholamines in mouse brains. We found that among eight synthetic dipeptides whose sequences are present frequently in soy proteins, Ser-Tyr (SY), Ile-Tyr
Amal Alachkar et al.
Neuroscience research, 67(3), 245-249 (2010-03-23)
The ability of l-3,4-dihydroxyphenylalanine (l-DOPA), l-DOPA-methyl ester and their major metabolites, dopamine, dihydroxyphenylacetic acid (DOPAC), homovanillic (HVA), 3-O-methyldopa and 3-methoxytyramine (3-MT) to bind to alpha(2) adrenergic and D1 and D2 dopamine receptors was assessed by radioligand binding to cloned human
Lucyna Antkiewicz-Michaluk et al.
European journal of pharmacology, 599(1-3), 32-35 (2008-10-14)
3-Methoxytyramine (3-MT), an extraneuronal metabolite of dopamine, present in the synaptic cleft at a very low amount (low nanomolar range), comparable to dopamine concentration, is generally regarded as a biologically inactive compound. We have shown in this study that 3-MT
Tsukasa Sasaki et al.
Chirality, 22(2), 258-261 (2009-06-06)
A solution of optically pure kynurenine (KYN), i.e., D-KYN or L-KYN, was administered intravenously to male Sprague-Dawley rats (10 mg kg(-1) ml(-1)). The time-course of changes in the concentrations of urinary monoamines and their metabolites such as 5-hydroxytryptamine (5-HT), 5-hydroxyindole
Ilona Klejbor et al.
Journal of neurochemistry, 97(5), 1243-1258 (2006-03-10)
Developing and mature midbrain dopamine (DA) neurons express fibroblast growth factor (FGF) receptor-1 (FGFR1). To determine the role of FGFR1 signaling in the development of DA neurons, we generated transgenic mice expressing a dominant negative mutant [FGFR1(TK-)] from the catecholaminergic
Edyta Możdżeń et al.
Neurotoxicity research, 27(3), 300-313 (2014-12-30)
Salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline), an endogenous compound present in the brain, was suspected of participation in the etiopathogenesis of Parkinson's disease, the most common serious movement disorder worldwide. In this study, we evaluated the effect of different (50, 100, and 500 µM)
Hui Gu et al.
Analytical and bioanalytical chemistry, 412(15), 3727-3736 (2020-04-30)
Electrochemical detection of dopamine (DA) usually depends on electrochemical oxidation of DA. This conventional method can hardly provide sufficient sensitivity and selectivity in the determination of the cerebral DA down to nanomolar level, because the ability of DA to be
Tatyana D Sotnikova et al.
PloS one, 5(10), e13452-e13452 (2010-10-27)
Dopamine (3-hydroxytyramine) is a well-known catecholamine neurotransmitter involved in multiple physiological functions including movement control. Here we report that the major extracellular metabolite of dopamine, 3-methoxytyramine (3-MT), can induce behavioral effects in a dopamine-independent manner and these effects are partially
Dilo Pillai et al.
Annals of clinical biochemistry, 47(Pt 2), 137-142 (2010-02-11)
Up to 2007 there was no formal external quality assurance programme for plasma free metanephrines. A pilot programme was conceived by the AACB (Australian Association of Clinical Biochemists) Working Party on biogenic amines. With support from the AACB and Royal
Bérengère Claude et al.
Analytica chimica acta, 699(2), 242-248 (2011-06-28)
Capillary electrophoresis (CE) has been investigated for the analysis of some neurotransmitters, dopamine (DA), 3-methoxytyramine (3-MT) and serotonin (5-hydroxytryptamine, 5-HT) at nanomolar concentrations in urine. Field-amplified sample injection (FASI) has been used to improve the sensitivity through the online pre-concentration
N van Duinen et al.
The Journal of clinical endocrinology and metabolism, 95(1), 209-214 (2009-11-10)
Patients with head-and-neck paragangliomas (HNPGL) are regularly screened for catecholamine excess. The clinical relevance of increased urinary secretion of 3-methoxytyramine is unclear in HNPGL. The aim of the study was to assess the prevalence and the clinical, biochemical, and radiological
N van Duinen et al.
European journal of endocrinology, 169(3), 377-382 (2013-07-09)
A substantial number of patients with head and neck paragangliomas (HNPGLs) have biochemically active tumors, evidenced by increased urinary excretion of catecholamines and metabolites, including 3-methoxytyramine (3MT). It is unclear whether plasma levels of these parameters are more sensitive to
G Muthian et al.
Neuroscience, 169(3), 1085-1093 (2010-06-15)
Idiopathic Parkinson's disease (PD) is a neurodegenerative disorder of mature and older individuals. Since all aged individuals do not develop PD, predisposing conditions may exist that pair with the stress placed on the basal ganglia during aging to produce the
A Vonaparti et al.
Drug testing and analysis, 1(8), 365-371 (2010-04-01)
Levodopa and dopamine have been abused as performance-altering substances in horse racing. Urinary 3-methoxytyramine is used as an indicator of dopaminergic manipulation resulting from dopamine or levodopa administration and is prohibited with a urinary threshold of 4 microg mL(-1) (free
Graeme Eisenhofer et al.
Clinical chemistry, 60(12), 1486-1499 (2014-10-22)
Pheochromocytomas and paragangliomas (PPGLs) are potentially lethal yet usually surgically curable causes of endocrine hypertension; therefore, once clinical suspicion is aroused it is imperative that clinicians choose the most appropriate laboratory tests to identify the tumors. Compelling evidence now indicates
Mirko Peitzsch et al.
Annals of clinical biochemistry, 50(Pt 2), 147-155 (2013-03-21)
Measurements of plasma normetanephrine (NMN) and metanephrine (MN) provide a sensitive test for diagnosis of phaeochromocytomas and paragangliomas (PPGLs), but do not allow detection of dopamine-producing tumours. Here we introduce a novel mass spectrometric based method coupled to ultraperformance liquid
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