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At least 613 records · Page 34Linked to original sources
PubMed2006

Determination of biogenic amines in wines by ion-pair liquid chromatography and post-column derivatization with 1,2-naphthoquinone-4-sulphonate.

A liquid chromatographic method with post-column derivatization for the determination of biogenic amines in wines is proposed. The method is based on the separation of amines by ion-pair chromatography using sodium heptanesulfonate (SHS) and on-line labeling of analytes with 1,2-naphthoquinone-4-sulfonate. The principal factors influencing the separation (acetonitrile and SHS concentration) have been considered for the optimization of the elution gradient through factorial design and multicriteria decision-making. Figures of merit have been established using red wine samples. Detection limits range from 0.2 to 3 mg L(-1), the peak area run-to-run repeatability from 1.6 to 4.6% and the retention time repeatability lower than 1.2%. Recoveries ranging from 92 and 108% prove the accuracy of the method for determining ethanolamine, ethylamine, histamine and tyramine in commercial red wines. The proposed method has been applied to the analysis of wines from different Spanish regions.

Biogenic Amines↗
PubMed2006

Determination of the biogenic amines in musts and wines before and after malolactic fermentation using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate as the derivatizing agent.

An accurate, rapid and sensitive high-performance liquid chromatographic (HPLC) method is reported for the determination of four biogenic amines in red and white wine samples. The method involves derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) followed by liquid chromatography gradient elution analysis without any other sample pretreatment. The procedure developed permitted the determination of the four amines in 40 min. The relative standard deviation (RSD) values ranged from 3.1% to 6.1% in peak areas and the response was linear (R2>0.994) in a range from 0.1 to 4 mg/l. Leaving aside putrescine in Tempranillo wines, the malolactic fermentation did not exert any effect on the concentration of these compounds. On the contrary, the influence of the grape variety was important, and Tempranillo wines showed higher levels of tyramine and histamine and lesser of putrescine and cadaverine (p<0.05) than wines made with Cabernet Sauvignon.

Aminoquinolines↗
PubMed2006

Analysis of amino acids and biogenic amines in biological tissues as their o-phthalaldehyde/ethanethiol/fluorenylmethyl chloroformate derivatives by high-performance liquid chromatography. A deproteinization study.

The extraction of ornithine, lysine, putrescine, cadaverine, 1,7-diaminoheptane, spermidine and spermine from biological tissues was optimized for HPLC quantitation as their o-phthalaldehyde/ethanethiol/fluorenylmethyl chloroformate (OPA/ET/FMOC) derivatives. In applying perchloric acid deproteinization two approaches have been followed: (i) deproteinization with subsequent neutralization by potassium hydroxide and lyophilization, and (ii) deproteinization without neutralization and lyophilization. Neutralization and lyophilization resulted in the loss of free biogenic amines. HPLC analysis of ornithine (Orn), lysine (Lys), putrescine (Put), cadaverine (Cad), 1,7-diaminoheptane (Dah), spermidine (Spd) and spermine (Spm) content of biological tissues as their OPA/ET/FMOC derivatives was performed in the supernatant of perchloric acid-deproteinized samples (model solutions and tissues) with an average reproducibility of < or =2.6% relative standard deviation (RSD), including recovery of sample treatment and chromatography.

Amino Acids↗
PubMed2003

Structural and functional probing of the biogenic amine transporters by fluorescence spectroscopy.

Fluorescence spectroscopy techniques have proven extremely powerful for probing the molecular structure and function of membrane proteins. In this review, it will be described how we have applied a series of these techniques to the biogenic amine transporters, which are responsible for the clearance of dopamine, norepinephrine, and serotonin from the synaptic cleft. In our studies, we have focused on the serotonin transporter (SERT) for which we have established a purification procedure upon expression of the transporter in Sf-9 insect cells. Importantly, the purified transporter displays pharmacological properties in detergent micelles similar to that observed in membranes suggesting that the overall tertiary structure is preserved upon purification. Using this purified SERT preparation and the fluorescent cocaine analogue RTI-233 as a molecular reporter, we have been able to characterize the microenvironment of the cocaine-binding pocket. In current follow-up studies, we are attempting to map the relative position of this binding pocket using fluorescence resonance energy transfer (FRET) between RTI-233 and an acceptor fluorophore covalently attached to endogenous cysteines in the transporter. Finally, it will be described how we recently initiated the implementation of single-molecule confocal fluorescence spectroscopy techniques in our studies of the SERT.

Animals↗
PubMed2005

HPLC with electrochemical and fluorescence detection procedures for the diagnosis of inborn errors of biogenic amines and pterins.

The analysis of biogenic amines (BA) and pterins in cerebrospinal fluid (CSF) is essential for the early diagnosis of neurotransmission defects in the paediatric age. Our aim was to standardize previously reported HPLC procedures for the analysis of BA and pterins in CSF and to establish reference values for a paediatric population. Samples from 127 subjects (age range 11 days to 16 years; average 3.8) were analyzed by HPLC with electrochemical and fluorescence detection. Both BA (homovanilic and 5-hydroxyindoleacetic acid) and pterins (neopterin and biopterin) concentrations in CSF showed a negative correlation with age. This finding led us to stratify reference values into six groups according to age. In conclusion, analysis of BA and pterins in CSF by HPLC procedures is a useful set of tools for the diagnosis of inborn errors of metabolism of these compounds. The establishment of reference intervals may be difficult, since there is a strong correlation between BA concentrations and the age of controls and, as a result, a large number of CSF samples from control populations would be necessary for this purpose.

Adolescent↗
PubMed2004

Effect of nitric oxide on prolactin secretion and hypothalamic biogenic amine contents.

Involvement of nitric oxide (NO) in the episodic secretion of prolactin was studied in conscious freely moving adult rats. Prolactin secretion was pulsatile in all animals of either group during the bleeding period (from 10:30 h to 13:30 h). Administration of N(omega)-nitro-L-arginine methyl ester (L-NAME), a NO synthase inhibitor, increased mean plasma levels of prolactin, and the absolute amplitude of prolactin peaks during the whole bleeding period as compared to values found in the control group. L-NAME increased norepinephrine (170%), dopamine (58.27%) and serotonin contents (30%) in the anterior hypothalamus. In the median eminence, dopamine and serotonin contents decreased (19.79% and 33.9% respectively) after L-NAME as compared to the values found in controls. In addition, norepinephrine content increased in mediobasal hypothalamus (79.6%) of rats treated with L-NAME. The results indicate that changes in NO production may modify the episodic secretion of prolactin. These effects were associated with changes in hypothalamic and median eminence biogenic amines.

Animals↗
PubMed2005

Analysis of cholinergic markers, biogenic amines, and amino acids in the CNS of two APP overexpression mouse models.

Two transgenic mouse models expressing mutated human amyloid precursor protein and previously found to display cognitive and behavioural alterations, reminiscent of Alzheimer patients' symptomatology, were scrutinised for putative brain region-specific changes in neurochemical parameters. Brains of NSE-hAPP751m-57, APP23 and wild-type mice were microdissected to perform brain region-specific neurochemical analyses. Impairment of cholinergic transmission, the prominent neurochemical deficit in Alzheimer brain, was examined; acetylcholinesterase and choline acetyltransferase activity levels were determined as markers of the cholinergic system. Since Alzheimer neurodegeneration is not restricted to the cholinergic system, brain levels of biogenic amines and metabolites, and amino acidergic neurotransmitters and systemic amino acids were analysed as well. Cholinergic dysfunction, reflected in reduced enzymatic activity in the basal forebrain nuclei, was restricted to the APP23 model, which also exhibited more outspoken and more widespread changes in other neurotransmitter systems. Significant changes in compounds of the noradrenergic and serotonergic system were observed, as well as alterations in levels of the inhibitory neurotransmitter glycine and systemic amino acids. These observations were clearly in occurrence with the more pronounced histopathological and behavioural phenotype of the APP23 model. As transgenic models often do not represent an end-stage of the disease, some discrepancies with results from post-mortem human Alzheimer brain analyses were apparent; in particular, no significant alterations in excitatory amino acid levels were detected. Our findings of brain region-specific alterations in compound levels indicate disturbed neurotransmission pathways, and greatly add to the validity of APP23 mice as a model for Alzheimer's disease. Transgenic mouse models may be employed as a tool to study early-stage neurochemical changes, which are often not accessible in Alzheimer brain.

Acetylcholine↗
PubMed2006

Biogenic amine changes in brain regions and attenuating action of Ocimum sanctumin noise exposure.

Broadband white noise exposure (100 dB) in wistar strain male albino rats significantly increased the levels of dopamine (DA), serotonin (5-HT) and 5-HT turnover in many of the discrete brain regions (cerebral cortex, cerebellum, hypothalamus, hippocampus, pons-medulla and corpus striatum) during sub-chronic noise exposure (4 h daily for 15 days). In acute (4 h for 1 day) and chronic noise exposures (4 h daily for 30 days) the levels were significantly altered only in certain regions. The turnover study of serotonin clearly indicates that neurotransmitter level alone cannot be an indicator, as in some brain regions the rate of synthesis matched with the degradation in order to maintain the normal levels. The intraperitoneal administration of 70% ethanolic extract of Ocimum sanctum(OS) at the dosage of 100 mg/kg body weight to animals subjected to noise exposure has prevented the noise induced increase in neurotransmitter levels without affecting the normal levels. This indicates that OS can be a probable herbal remedy for noise induced biogenic amine alterations.

Animals↗
PubMed2004

Sex hormones and biogenic amine turnover of sex offenders in relation to their temperament and character dimensions.

Relationships between Cloninger's temperament and character dimensions and plasma sex hormone levels and biogenic amine turnover were studied in male prison inmates convicted of rape (n=61) or child molestation (n=24) and normal male controls (n=25). The participants completed the Temperament and Character Inventory (TCI), which includes the temperament dimensions Novelty Seeking, Harm Avoidance, Reward Dependence and Persistence as well as the character dimensions Self-Directedness, Cooperativeness and Self-Transcendence. Plasma levels of testosterone, dihydrotestosterone, sex hormone binding globulin, luteinizing hormone (LH) and follicle-stimulating hormone were estimated in plasma samples and 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) in urine samples. Both sex offender groups had higher Novelty, Seeking and lower Reward Dependence, Self-Directedness and Cooperativeness scores compared with the controls. Plasma levels of testosterone and dihydrotestosterone were significantly higher in rapists than in controls. Novelty Seeking scores were positively correlated with LH levels in rapists, and with testosterone levels in child molesters. Harm Avoidance scores were negatively correlated with 5-HIAA levels in rapists and with HVA levels in child molesters. In rapists, the calculated free androgen index showed a negative correlation with 5-HIAA. For the sex offender sample as a whole, the subgroup with high testosterone levels had higher Harm Avoidance scores, the subgroup with low HVA levels had lower Cooperativeness scores, and the subgroups with high 5HIAA or MHPG levels had lower Persistence scores. The results indicate that Novelty Seeking behavior in the group of rapists is associated with a hyperactive hypothalamic-pituitary-gonadal axis. In addition, low serotonin turnover and low dopamine turnover seem to be associated with a passive-avoidant behavioral style in rapists and child molesters, respectively.

Adult↗
PubMed1984

Noncovalent complexes of diadenosine 5',5"'-P1,P4-tetraphosphate with divalent metal ions, biogenic amines, proteins and poly(dT).

Diadenosine 5',5'''-P1,P4-tetraphosphate was shown by circular dichroic measurements to bind to metal ions (Mg2+, Ca2+, Mn2+, Co2+, Zn2+), to biogenic amines (cadaverine, putrescine, spermidine, spermine), to L-arginine, to proteins (lysozyme, bovine serum albumin, Arg-rich histone f3, Lys-rich histone), and to poly(dT). Most cations effect destacking of the intramolecular adenine rings. Poly(dT) bound to the dinucleotide with a stoichiometry of 2 residues TMP per molecule of adenosine 5',5'''-P1,P4-tetraphosphate.

Adenine Nucleotides↗
PubMed1976

Coordination of biogenic amines with synaptosomal and vesicular metal ions: equilibrium and spectral studies in model systems.

Thermodynamic equilibrium studies using model systems were carried out on the nature and extent of coordination of twelve different biogenic amines and adenosine-5'-triphosphate (ATP) with the bivalent metal ions, viz., Ca2+ and Zn2+, which occur in the subcellular fractions of the brain, at 25.0 +/- 0.1 degrees C and at an ionic strength of 1.0 (KNO3). In the combined presence of the individual monoamines and ATP the metal ions were predominantly coordinated by ATP in the pH range 3.0 to 6.5 with binding constants (log KML) of 2.84 +/- 0.06 and 3.19 +/- 0.39 for the Ca2+ and Zn2+ chelates, respectively. Each of the monoamines coordinated with the metal-ATP chelate above pH 6. The stabilities of the chelates of some of the amines with Ca2+ -ATP (1:1) system were NE, 2.33 +/- 0.33; AA, 2.24 +/- 0.19; OA, 1.94 +/- 0.29; NMeN, 1.60 +/- 0.22; DA, 2.14 +/- 0.09. Values for the Zn2+-ATP-amine systems were: NE, 8.35 +/- 0.26; OA, 4.53 +/- 0.07; DA, 10.05 +/- 0.39. Absorption spectral studies were carried out in order to examine the nature of coordination of NE, DA, TA, and AA with Cu2+, Fe2+, and Mg2+ ions in the combined presence of ATP. Results of the spectral studies taken together with the (thermodynamic) equilibrium data have indicated that in the pH range of biological interest, the catechol amines (NE and DA) and ATP are both coordinated to the "synaptosomal and vesicular" metal ions. The results further indicated that both the pyrocatechol and the ethanolamine groups of NE might be involved in the coordination of Cu2+. However, the interaction of the ethanolamine group of the NE molecule with the rest of the metal ions was not indicated.

Adenosine Triphosphate↗
PubMed1999

Biogenic amine activity in response to fluoxetine and desipramine in differentially reared rhesus monkeys.

BACKGROUND: It has been hypothesized that adverse early experience may be a mechanism by which children become vulnerable to later psychopathology via alteration of neurochemical or hormonal systems associated with such disorders. Such effects may in turn affect later responses to pharmacologic agents that act on these systems. METHODS: In this study, 18 mother-reared (MR) and 18 peer-reared (PR) rhesus monkeys experienced six 1-week separations from cagemates interspersed with 1-week reunions, while housed in like-reared groups of 3. Within rearing groups, equal numbers of animals received either fluoxetine (2 mg/kg), desipramine (5 mg/kg) or placebo delivered daily beginning 4 weeks before the first separation. Levels of norepinephrine (NE), the NE metabolite MHPG, the dopamine metabolites DOPAC and HVA, and the serotonin metabolite 5HIAA were measured in CSF samples collected approximately every 2 to 3 weeks during these procedures. RESULTS: Following treatment, DMI increased NE and decreased MHPG in the DMI-treated groups, while 5HIAA was decreased in the fluoxetine-treated groups following treatment. The increase in NE was followed by a sharp decline over the course of treatment, which was accompanied by an increase in MHPG. The rearing groups did not show a differential response to the drug treatments, and the separation manipulation itself had few effects. The mother-reared group showed higher levels of NE and DOPAC over all samples and higher levels of HVA in most samples. CONCLUSIONS: These rearing effects on biogenic amine activity were observed even in the presence of pharmacologic treatments that effectively altered the activity of these systems, and are consistent with previous findings from the same subject. The higher NE values observed in mother-reared infants over separations and reunions may have been due to higher basal levels of NE than peer-reared monkeys or to greater responsiveness to the stress of repeated social disruption or both. These findings agree with other primate studies showing that rearing differences persist beyond the infancy period and add to growing evidence of the important influence of the early social environment on neurobiologic development in primates.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2001

Fourier transform Raman study of the structural specificities on the interaction between DNA and biogenic polyamines.

Biogenic polyamines putrescine, spermidine, and spermine are essential molecules for proliferation in all living organisms. Direct interaction of polyamines with nucleic acids has been proposed in the past based on a series of experimental evidences, such as precipitation, thermal denaturation, or protection. However, binding between polyamines and nucleic acids is not clearly explained. Several interaction models have also been proposed, although they do not always agree with one another. In the present work, we make use of the Raman spectroscopy to extend our knowledge about polyamine-DNA interaction. Raman spectra of highly polymerized calf-thymus DNA at different polyamine concentrations, ranging from 1 to 50 mM, have been studied for putrescine, spermidine, and spermine. Both natural and heavy water were used as solvents. Difference Raman spectra have been computed by subtracting the sum of the separated component spectra from the experimental spectra of the complexes. The analysis of the Raman data has supported the existence of structural specificities in the interactions, at least under our experimental conditions. These specificities lead to preferential bindings through the DNA minor groove for putrescine and spermidine, whereas spermine binds by the major groove. On the other hand, spermine and spermidine present interstrand interactions, whereas putrescine presents intrastrand interactions in addition to exo-groove interactions by phosphate moieties.

Animals↗
PubMed2001

Biogenic amines in the human neocortex in patients with neocortical and mesial temporal lobe epilepsy: identification with in situ microvoltammetry.

Biogenic amines in well defined subtypes of human temporal lobe epilepsy (TLE) have not been well characterized. Specimens from five patients with neocortical TLE (NTLE) and nine with mesial TLE (MTLE) were immediately placed in Ringer's lactate; stearate indicator microelectrodes were placed in temporal gray matter, Ag/AgCl reference microelectrodes and auxiliary microelectrodes were placed 3-7 mm contralaterally to the indicator microelectrode. Dopamine (DA), ascorbic acid (AA), norepinephrine (NE) and serotonin (5-HT) were identified by their characteristic oxidative potentials in vitro. Four of five patients with NTLE had NE depletion in temporal neocortex while eight of nine patients with MTLE had high concentrations of NE (chi-square P<0.01). Significant concentrations of DA were present in the temporal lobes of three of five NTLE patients but in only one of the nine MTLE patients (chi-square P<0.05). 5-HT was present in the neocortex of both NTLE and MTLE patients in similar concentrations. AA was found in the neocortex of one NTLE patient. These data support an association between NE depletion and NTLE. The relative NE deficiency along with the consistent presence of DA in NTLE patients suggest an impairment in the catecholamine pathway. The presence of AA, a co-factor in NE synthesis, in the neocortex of one NTLE patient may also be related since AA is a cofactor in NE synthesis.

Biogenic Amines↗
PubMed1986

Effect of hypoxia on brainstem concentration of biogenic amines in postnatal rabbits.

The effects of hypoxia FiO2 = 0.10 on concentration of biogenic amines in specific brainstem nuclear groups were investigated in 3-and 21-day-old rabbits. The rabbit pups were confined to temperature-controlled water-jacketed chambers and exposed to 6h of 21% O2 or to one of 3 combinations of 21% O2 and 10% O2. These 3 combinations were either intermittent hypoxia, or 4 h of normoxia followed by 2 h constant hypoxia, or 2 h of hypoxia followed by recovery for 4 h in normoxia. Radioenzymatic assays were used to determine the concentration of dopamine, norepinephrine and serotonin in the following brainstem nuclei: substantia nigra, locus coeruleus, dorsal raphe and the nucleus reticularis pontis oralis. Compared with control, hypoxia did not affect dopamine levels at either age. The concentration of norepinephrine was inconsistently affected by hypoxia at either age. In contrast, in the 3-day-old rabbits serotonin was consistently reduced in each of the nuclei. In the 21-day-old rabbits, serotonin was either unchanged or increased following hypoxia. Our results show that hypoxia alters the concentration of serotonin in an age-specific manner. This change in serotonin concentration may reflect altered serotonin metabolism and suggests a possible mechanism by which hypoxia disrupts physiologic homeostasis in newborns.

Acute Disease↗
PubMed1992

Effects of manganese forms on biogenic amines in the brain and behavioral alterations in the mouse: long-term oral administration of several manganese compounds.

This work has identified the relative toxicity of four forms of manganese, using biogenic amine levels, tissue retention, weight gain, and activity scores as criteria. Male mice were chronically treated with four forms of manganese administered orally, mixed with the diet, for 12 months. The food intake for the control mice and the mice exposed to manganese was similar, but the manganese treatment reduced normal weight gain in the mice. The Mn levels were higher in some parts of brain after feeding insoluble salts than after the soluble salts. The concentration of manganese was significantly increased in the liver and spleen of the manganese carbonate-exposed group, compared with the concentration in the control group. Manganese dioxide feeding lowered dopamine and increased homovanilic acid. Since manganese dioxide is a powerful oxidizing agent in organic chemistry, it possibly enhanced the oxidative metabolite of dopamine. Accumulation of manganese in the brain correlated with reduced hypothalamic dopamine levels in the manganese acetate-exposed group; and the amount of manganese accumulated correlated with the intensity of suppression of motor activity. These findings indicate that manganese dioxide is more toxic than divalent manganese. Of the divalent manganese compounds, manganese acetate seemed to have the greatest toxic effect.

Animals↗
PubMed1998

The CRH-ACTH-biogenic amine axis in invertebrate immunocytes activated by PDGF and TGF-beta.

In immunocytes from the mollusc Mytilus galloprovincialis, the major pathway followed by platelet-derived growth factor (PDGF)-AB and transforming growth factor (TGF)-beta1 in provoking the release of norepinephrine, epinephrine and dopamine into cell-free hemolymph (serum) is mediated by a corticotropin-releasing hormone-adrenocorticotropin hormone (CRH-ACTH) biogenic amine axis. This axis not only annulled the inhibiting properties of PDGF-AB, it even reversed the latter's effect, while the inducing effect of TGF-beta1 was amplified. These findings show that non-classical immune-neuroendocrine molecules, such as PDGF-AB and TGF-beta1, are involved in building stress response, using the same conserved mechanisms present from invertebrates to vertebrates.

Adrenocorticotropic Hormone↗
PubMed2000

Liquid chromatographic determination of biogenic amines in fermented foods after derivatization with 3,5-dinitrobenzoyl chloride.

The reagent 3,5-dinitrobenzoyl chloride (DNBZ-Cl) was tested for pre-column derivatization of biogenic amines (BAs). Samples were derivatized within 3 min in 1 M NaOH at ambient temperature by adding 2-propanole and 50 mM DNBZ-Cl in acetonitrile. The reaction was terminated by addition of 2 M HCl. For high-performance liquid chromatography an encapsulated stationary reversed-phase and gradient elution using a ternary gradient system were used. The DNBZ derivatives were quantified by their UV-absorption at 260 nm. The structures of the derivatives were elucidated using coupling of HPLC with electrospray ionization mass spectrometry. Detection limits of BAs were approximately 124-864 microg l(-1) (injected amounts 203-1410 pg) at a signal-to-noise ratio of 3:1. The coefficients of determination were 0.989-0.996, with the exceptions of cadaverine (0.976) and serotonin (0.965). The method was applied to the quantitative determination of agmatine, cadaverine, histamine, octopamine, 2-phenylethylamine, putrescine, serotonin, spermidine, spermine, tryptamine and tyramine, in fermented cabbage juices, soy sauces, Misos (soy pastes), fermented fish sauces, and anchovy paste.

Biogenic Amines↗