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At least 649 records · Page 36Linked to original sources
PubMed1979

Selected ion monitoring assay for biogenic amine metabolites and probenecid in human lumbar cerebrospinal fluid.

Details are presented of an improved selected ion monitoring assay for the major biogenic amine metabolites and probenecid in human lumbar cerebrospinal fluid (CSF). The metabolites and probenecid are simultaneously extracted with ethyl acetate from an acidified aqueous phase, and are simultaneously converted to pentafluoropropionyl esters by reaction with pentafluoropropionic anhydride and pentafluoropropanol. The esters of the metabolites are analyzed following a single injection of the derivatized sample onto the gas chromatographic column, while the ester of probenecid is analyzed following a separate injection onto the gas chromatographic column. Quantitation is achieved using for internal standards dueterated analogues of the metabolites and a chemical analogue of probenecid. Data are presented on the concentration of free and conjugated forms of the metabolites in lumbar CSF taken from healthy volunteers.

Biogenic Amines↗
PubMed1977

Chromatography of biogenic amines. I. Generally applicable separation and detection methods.

This first part of the review on "Chromatography of Biogenic Amines" is devoted to the description of generally applicable separation and detection methods. Gas chromatographic and gas chromatographic-mass spectrometric methods, and applications of chromatographic methods to specific amines or groups of related amines and their metabolites, will be covered in Part II. Trends in the development of separation methods (paper and thin-layer chromatography, paper and thin-layer electrophoresis and ion-exchange methods) are described, using mostly aliphatic amines as examples as they do not exhibit features that permit their specific determination. Reagents suggested for the formation of coloured and fluorescent derivatives of amines are reviewed and their applications are described. Within the limitation of the reviewed and their applications are described. Within the limitation of the mostly inadequate information that is available, the relative usefulness of the different derivative-forming reactions are compared.

Biogenic Amines↗
PubMed1989

Analysis of biogenic amines in the brain of the American cockroach (Periplaneta americana) by gas chromatography-negative ion chemical ionisation mass spectrometry.

Biogenic amines in the brain of the American cockroach have been identified and quantified by an extraction-derivatisation procedure involving their reaction with ditrifluoromethylbenzoyl chloride (DTFMB) in the aqueous phase followed by extraction into an organic solvent, hydrolysis of phenolic esters and conversion of free hydroxyl groups to trimethylsilyl (TMS) ethers and subsequent analysis by gas chromatography-negative ion chemical ionisation mass spectrometry. The molecular ion of these DTFMB-TMS derivatives carried most of the ion current which made the method highly specific and gave a potential limit of detection below the picogram level. This method establishes unequivocally that the principal amines in cockroach brain are tyramine, p-octopamine, dopamine, 5-hydroxytryptamine and noradrenaline. In contrast to mammalian nervous tissue, the other positional isomers of octopamine, together with the isomeric synephrines, are absent.

Animals↗
PubMed1986

Simultaneous analysis of twelve biogenic amine metabolites in plasma, cerebrospinal fluid and urine by capillary column gas chromatography-high-resolution mass spectrometry with selected-ion monitoring.

A procedure is described for the simultaneous determination of twelve acidic and alcoholic metabolites of trace and catecholic biogenic amines in plasma, cerebrospinal fluid and urine by capillary column gas chromatography--high-resolution mass spectrometry. Protein precipitation with sulphosalicylic acid, derivatization with two different reagent systems, final sample clean-up with a buffer wash and a program for automatically changing the reference mass of the mass spectrometer to suit each group of compounds as they are eluted from the column, are the main novel features of the procedure. A brief description of the synthesis of the deuterium-labelled internal standards is provided. The procedure is applied to biological samples and a comparison to reported values is given.

Biogenic Amines↗
PubMed1984

Quantification of a number of biogenic amines and their metabolites in brain homogenates by gas chromatography--mass spectrometry.

A sensitive method is described for the assay of various biogenic amines and their metabolites from brain tissue homogenates. Based on gas chromatography-mass spectrometry and selected ion monitoring, the method allows reliable low-level quantification of the compounds of interest. By careful study of reaction conditions both in the preparation of derivatives for gas chromatography and in the synthesis of deuterated analogues for internal standard use, relatively simple procedures could be applied with good analytical efficiency. Correlation of the results with those obtained by a high-performance liquid chromatographic procedure was also investigated, and a neurologic application of the method is briefly discussed.

Alzheimer Disease↗
PubMed1997

High-performance liquid chromatographic determination of biogenic amines in fish implicated in food poisoning.

A rapid, sensitive and reproducible high-performance liquid chromatographic procedure for the determination of nine biogenic amines in fish by improved benzoylation with benzoyl chloride was developed. The benzoylation of amines with benzoyl chloride at 30 degrees C for 40 min was the optimal condition to eliminate the influence of interfering peaks during analysis. The calibration curve for each amine was linear within the range of 0.02-4 microg. The amine recovery from fish meat was better by extraction with 6% trichloroacetic acid than with 1 M HClO4. The application of this method to detect amines in a fried marlin fillet implicated in a food poisoning incident indicated that a high level (84.1 mg/100 g) of histamine was present in the sample.

Animals↗
PubMed1998

High-performance liquid chromatographic analysis of biogenic amines in cells and in culture media using on-line dialysis and trace enrichment.

A highly sensitive method is presented for the automatic quantitative detection of DOPA metabolites in low concentrations in cells derived from the neural crest using reversed-phase HPLC in combination with fluorescence and electrochemical detection. The HPLC system was combined with on-line dialysis and on-line trace enrichment for the detection of small quantities of DOPA metabolites in culture media. Parameters like detector settings, pH, dialysis time and flow-rates are evaluated and optimized. Static-continuous dialysis can be performed at a low flow-rate concomitant with a high dialysis efficiency (up to >65%) depending on the type of DOPA metabolite. Counterflow dialysis can be used to analyse, with low efficiencies (17-29%), samples consisting of large volumes. Samples containing up to at least 7% (w/v) protein can be analysed in the low flow-rate static-continuous mode. In this last mode of dialysis, limits of detection for dopamine, norepinephrine, epinephrine and n-methyldopamine in DMEM/HAMF12 medium samples are 100 fmol or even lower. Serotonin is detectable at 10 fmol at a signal/noise ratio of 3. Biogenic amines were detectable at a concentration of 10 fmol/microl in a volume of 100 microl medium with an intra- and inter-assay imprecision <6.4%. This method is applied to study the differentiation level of tumour cells in culture and slices of a tumour derived from the neural crest. With this system, we also detected the excretion of DOPA metabolites from PC-12 cells after treatment with prenylamine.

Animals↗
PubMed1997

Behaviour of resolution by changing solvent strength and selectivity in the 'PRISMA' model using reversed-phase HPLC for biogenic amines.

The retention behaviour of 17 dansylated biogenic amines in 6 linear gradients at 13 solvent combinations, expressed by the selectivity points (Ps) according to the 'PRISMA' model, was investigated. The dependence between the retention times (tr) and different gradients was examined. Three dimensional resolution (Rs) maps for each peak-pair in the different gradients at the 13 selectivity points were constructed, and the affect of the gradients on separation were investigated. The study showed that the dependence between the gradients and tr values of dansyl amides can be expressed using quadratic functions with a high degree of accuracy. These functions are well suited for estimating the resolution in different gradients and Ps. The three dimensional Rs maps clearly demonstrated the changes between the different gradients and Ps. This was of considerable benefit when searching the optimum mobile phase by changing both the solvent strength (ST) and selectivity.

Biogenic Amines↗
PubMed1999

Sensitive amperometric biosensor for the determination of biogenic and synthetic amines using pea seedlings amine oxidase: a novel approach for enzyme immobilisation.

We prepared a new inorganic sorbent based on modified triazine (2-[4,6-bis (aminoethylamine)-1,3,5-triazine]-Silasorb; BAT-Silasorb) which binds pea seedlings amine oxidase (PSAO) very tightly without loss of its catalytic activity. This unique feature as well as the wide substrate specificity of PSAO was successfully utilised in the construction of an amperometric biosensor based on a carbon paste electrode for the fast and sensitive detection of various amines at a formal potential 0 mV versus Ag/AgCl reference electrode. The reaction layer of the biosensor is created by the direct immobilisation of PSAO at the electrode surface via affinity carrier BAT-Silasorb. Used arrangement facilitates a simple restoration of the inactive biosensor. An amperometric signal results from horseradish peroxidase catalysed reduction of H2O2, a secondary product of the oxidative deamination of amines, catalysed by PSAO. The sensor was used for the basic characterisation of 55 biogenic and synthetic amines, from numerous mono-, di- and polyamines to various hydroxy-, thio-, benzyl- and aromatic derivatives in order to establish its suitability as a postcolumn detector. Its high sensitivity to putrescine 20.0 +/- 0.64 mA l-1 per mol (636.9 +/- 2.03 mA l-1 per mol per cm2), a limit of detection of 10 nmol l-1 (determined with respect to a signal-to-noise ratio 3:1), a linear range of current response to 0.01-100 mumol l-1 concentration of substrate and good reproducibility all indicate that the sensor could be applied to future industrial and clinical analyses.

Amine Oxidase (Copper-Containing)↗
PubMed2000

Biogenic amine transporters: regulation in flux.

Following vesicular release, the biogenic amine neurotransmitters dopamine, norepinephrine and serotonin are actively cleared from extracellular spaces by presynaptic transporters. These transporters interact with multiple psychoactive agents including cocaine, amphetamines and antidepressants. Recent findings indicate that amine reuptake is likely to be a tightly regulated component of synaptic plasticity rather than a constitutive determinant of transmitter clearance. Protein kinase C activation and transporter phosphorylation have been linked to regulatory protein trafficking, and both phosphorylation and trafficking may be influenced by transporter ligands. Recognition that transmitters, antagonists and second messengers can modify the intrinsic activity, surface expression or protein levels of amine transporters raises new questions about the fundamental nature of drug actions in vivo. The theory that dysregulation of transporters may contribute to disease states is supported by the recent discovery that a coding mutation in the human norepinephrine transporter contributes to orthostatic intolerance.

Biogenic Monoamines↗
PubMedDate not supplied

Concentrations of biogenic amines in fundal layers in chickens with normal visual experience, deprivation, and after reserpine application.

Previous experiments in chickens have shown that dopamine released from the retina may be one of the messengers controlling the growth of the underlying sclera. It is also possible, however, that the apparent relationship between dopamine and myopia is secondary and artifactual. We have done experiments to assess this hypothesis. Using High Pressure Liquid Chromatography with electrochemical detection (HPLC-ED), we have asked whether changes in dopamine metabolism are restricted to the local retinal regions in which myopia was locally induced. Furthermore, we have measured the concentrations of biogenic amines separately in different fundal layers (vitreous, retina, choroid, and sclera) to find out how changes induced by "deprivation" (= removal of high spatial frequencies from the retinal image by translucent eye occluders which produce "deprivation myopia") are transmitted through these layers. Finally, we have repeated the deprivation experiments after intravitreal application of the irreversible dopamine re-uptake blocker reserpine to see how suppression of dopaminergic transmission affects these changes. We found that (1) Alterations in retinal dopamine metabolism were indeed restricted to the retinal areas in which myopia was induced. (2) The retina was the major source of dopamine release with a steep gradient both to the vitreal and choroidal side. Vitreal content was about one-tenth, choroidal content about one-third, and scleral content about one-twentieth of that of the retina. (3) There was a drop by about 40% in vitreal dopamine, DOPAC (3,4-dihydroxyphenylacetic acid) and HVA (homovanilic acid) concentrations following deprivation which occurred already at a time where little changes could yet be seen in their total retinal contents. (4) Choroidal and scleral dopamine levels were not affected by deprivation, indicating that other messengers must relay the information to the sclera. (5) A single intravitreal injection of reserpine lowered dopamine and HVA levels in retina and vitreous for at least 10 days in a dose-dependent fashion and diminished or suppressed further effects of deprivation on these compounds. DOPAC levels continued to change upon deprivation even after reserpine injection (Fig. 3). Our results suggest that the release rates of dopamine from retinal amacrine cells can be estimated from vitreal dopamine concentrations; furthermore, they are in line with the hypothesis that there is an inverse relationship between dopamine release and axial eye growth rates. Although our experiments do not ultimately prove that dopamine has a functional role in the visual control of eye growth, they are in line with this notion.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1998

Prenatal stress alters brain biogenic amine levels in primates.

In this study, we assessed behavioral responses to social separation at 8 months of age and cerebrospinal fluid (CSF) concentrations of biogenic amines and metabolites at 8 and 18 months of age in 12 rhesus monkeys derived from either stressed or undisturbed pregnancies. Compared to controls from undisturbed pregnancies, prenatal stress-derived monkeys had higher concentrations of 3-methoxy-4-hydroxyphenylglycol (MHPG), and 3,4-dihydroxyphenylacetic acid in CSF than controls. Norepinephrine and MHPG response to stress were both correlated between 8 and 18 months of age. There were few group differences in behavior during social separation; however, several behavioral differences between groups were found when monkeys were reunited with cage mates. Prenatally stressed monkeys spent more time clinging to their surrogates and exploring (including eating and drinking), while controls showed more locomotion and social play with their cage mates. Collectively, our findings suggest that chronic unpredictable psychological stress during pregnancy has long-lasting effects on noradrenergic and dopaminergic activity and behavior in the offspring of gestationally stressed primate mothers.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2000

Electrooxidation mechanism of biogenic amines at amine oxidase modified graphite electrode.

Amine oxidase (AO, EC. 1.4.3.6) was previously shown to be a very efficient biological recognition element of amperometric biosensors for monitoring biogenic amines. The enzyme was effectively working in both mono- and bienzyme electrode designs, based on either a direct or a mediated electron-transfer pathway. This work focuses on the elucidation of the electron-transfer mechanism of the monoenzymatic unmediated AO-modified biosensor. The observed unmediated catalytic currents were assumed to be caused by (i) a direct electron-transfer process, (ii) the electrooxidation of the formed product, or (iii) their combination. Experiments supporting these assumptions are discussed in detail.

Amine Oxidase (Copper-Containing)↗
PubMed2005

Analysis of biogenic amine variability among individual fly heads with micellar electrokinetic capillary chromatography-electrochemical detection.

Neurochemical variability among individual Drosophila heads has been examined with the sensitivity of electrochemical detection and the selectivity of micellar electrokinetic capillary chromatography. Homogenization of single Drosophila heads in volumes as small as 100 nL has been accomplished. Here we demonstrate reproducible separations for single fly heads in 250-nL volumes providing a 4-fold increase in sensitivity without overloading the electrochemical detector. This increase in sensitivity allows detection of previously undetected analytes, such as N-acetyltyramine (naTA) and octopamine (OA). Analytes including L-3,4-dihydroxyphenylalanine, N-acetyl octopamine, N-acetyldopamine, naTA, N-acetylserotonin, OA, dopamine, tyramine, and serotonin also have been consistently identified in single-head homogenates and observed with homogenates representing populations of Drosophila. Neurochemical variation between individual flies as well as the consistency within a population indicates varying amounts of neurotransmitter turnover. The inception, design, and fabrication of a miniature tissue homogenizer has enabled the separation of biogenic amines and metabolites from these severely volume-limited single Drosophila head homogenates.

Animals↗
PubMed1990

Energetics of reserpine binding and occlusion by the chromaffin granule biogenic amine transporter.

The energetics of reserpine binding to the bovine adrenal biogenic amine transporter suggest that H+ ion translocation converts the transporter to a form which binds reserpine essentially irreversibly. Reserpine binding to bovine adrenal chromaffin granule membrane vesicles is accelerated by generation of a transmembrane pH difference (delta pH) (interior acid) or electrical potential (delta psi) (interior positive). Both components of the electrochemical H+ potential (delta mu H+) must be dissipated to block reserpine binding, and generation of either one stimulates the binding rate. Reserpine binding is less dependent than amine transport on the delta pH, suggesting that translocation of fewer H+ ions is required to expose the high-affinity site than are required for net transport. Bound reserpine dissociates very slowly, if at all, from the transporter. Binding is stable to 1% cholate, 1.5% Triton X-100, 1 M SCN-, and 8 M urea, but sodium dodecyl sulfate (0.035%) and high temperatures (100 degrees C) released bound reserpine, indicating that binding is noncovalent. The results raise the possibility that the transporter, by translocating one H+ ion outward down its concentration gradient, is converted to a form that can either transport a neutral substrate molecule inward or occlude reserpine in a dead-end complex.

Adenosine Triphosphatases↗
PubMed2000

Biogenic amines and polyamines in milks and cheeses by ion-pair high performance liquid chromatography.

The proposed chromatographic method provides a complete resolution of twelve amines in a single run in milks and unripened cheeses, avoiding the losses of resolution linked to fluctuations in working temperature. We also propose an alternative chromatographic gradient, which can be useful for samples that have undergone long ripening periods, like ripened cheeses. According to the results of the reliability study, the method described was precise, accurate, and sensitive. The method was applied to several samples of milks and cheeses and the results showed that the biogenic amine profiles varied greatly, not only between different types of samples but also among the samples from the same kind of products. In unripened cheeses, milks, and yogurts, spermidine and spermine were the prevailing amines, but in ripened cheeses the major amine was tyramine, followed by putrescine and cadaverine.

Animals↗
PubMed2002

Content of biogenic amines in a Chardonnay wine obtained through spontaneous and inoculated fermentations.

This paper describes the content of biogenic amines in wines obtained from a Chardonnay must inoculated with different strains of Saccharomyces cerevisiae and in a wine fermented with the indigenous yeasts (control wine). The concentrations of nonvolatile amines and phenethylamine in the wines from the inoculated must were superior to those of the control wine. This was probably due to the fact that consumption of the precursor amino acids of these amines, during fermentation, was also greater in the inoculated samples than in the control sample. Furthermore, from the results obtained it may be said that, at least to some extent, the nonvolatile amines were formed by yeasts during fermentation. The concentrations of dimethylamine, ethylamine, and pyrrolidine (volatile amines) were different for the different wines, although they did not reach concentrations sufficiently high to have any effect on the aroma.

Biogenic Amines↗
PubMed2002

Characterization of selected Spanish table wine samples according to their biogenic amine content from liquid chromatographic determination.

Pattern recognition techniques, such as principal component analysis, cluster analysis, and linear discriminant analysis, have been applied to samples of red, white, and rosé wines to determine whether some biogenic amines could be considered as chemical descriptors. Eight amines (tryptamine, phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine, and spermine) were determined by RP-HPLC, after derivatization with dabsyl chloride. However, only putrescine, cadaverine, histamine, tyramine, spermidine, and spermine were found in the wines analyzed. From the association between variables obtained by principal component analysis and clustering and from the relationship found by linear discriminant analysis, it can be deduced that the amines generated during malolactic fermentation (putrescine, histamine, and tyramine) could be used as chemical descriptors to characterize table wine samples.

Analysis of Variance↗