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PubMed1992

Cerebrospinal fluid biogenic amine metabolites in fibromyalgia/fibrositis syndrome and rheumatoid arthritis.

OBJECTIVE: To compare the levels of biogenic amines in the cerebrospinal fluid (CSF) of primary fibromyalgia syndrome (PFS) patients with those in the CSF of controls. METHODS: Metabolites of serotonin, norepinephrine, and dopamine were identified in CSF, using high performance liquid chromatography with coulometric detection. RESULTS: CSF levels of metabolites from all 3 neurotransmitters were lower in PFS patients than in controls. CONCLUSION: A low rate of turnover of several neurotransmitters supports the proposed hypothesis of a metabolic defect in PFS and suggests that the defect occurs at a neuroregulatory level.

Adult↗
PubMed1979

Some new fluorescent derivatives for the mass spectrometric quantitation of biogenic amines.

The 5-dimethyl-, diethyl-, dipropyl-, dibutyl-, and dipentyl-aminoaphghalene-1-sulfonyl (dansyl, ethanyl, propansyl, bansyl and pentansyl respectively) derivatives of tyramine and other biogenic amines were prepared and their mass spectra recorded. The relative intensity of the largest unique ion increased with increasing length of the alkyl group. Several O-alkyl-N-propansyl- and N,O-dialkyl-N-propansyl-, bansyl- and pentansyl-tyramines were also synthesized and their mass spectra recorded. Dimethylbansyl- and dimethylpentansyl-tyramines exhibited the largest unique ions in their mass spectra and the greatest sensitivity in quantitation by the integrated ion current method. Procedures for preparing these derivatives in amounts ranging from nanograms to milligrams are presented and their thin-layer chromatographic behavior in three solvent systems is described.

Biogenic Amines↗
PubMed1987

A comparison of the gas chromatographic and mass spectrometric properties of the pentafluoropropionyl and heptafluorobutyryl derivatives of the methyl, trifluoroethyl, pentafluoropropyl and hexafluoroisopropyl esters of twelve acidic metabolites of biogenic amines.

The gas chromatographic and mass spectrometric properties of the methyl, trifluoroethyl, pentafluoropropyl and hexafluoroisopropyl esters of the pentafluoropropionyl and heptafluorobutyryl derivatives of twelve important acidic metabolites of biogenic amines have been investigated. The optimum derivatization conditions for the different classes of metabolites have been established and the byproducts formed in some of the derivatizations have been identified. Under certain derivatizing conditions, back-exchange of deuterium in the labelled internal standards was observed. No single derivative appears to be ideally suitable for the simultaneous quantitative analysis by GC/MS of all twelve metabolites, so extracts of plasma and urine were split and a combination of the methyl or trifluoroethyl esters of the pentafluoropropionyl derivatives were used.

Biogenic Amines↗
PubMed1997

Capillary zone electrophoresis at subzero temperatures II: chiral separation of biogenic amines.

The separation of enantiomer pairs of eight biogenic amines by capillary zone electrophoresis (CZE) was investigated with heptakis (2,6-di-O-methyl)-beta-cyclodextrin as the chiral selector at temperatures ranging from -20 degrees to 40 degrees C by using a commercial electrophoresis unit retrofitted with an external thermostated refrigerated circulating bath in order to assist the original cooling system. Sodium phosphate in both neat aqueous and methanolic media at pH 2.5, as measured by the glass pH electrode, were used with the fused silica capillary from 1.5 degrees to 40 degrees C and -20 degrees to 40 degrees C, respectively. The effect of temperature on enantioselectivity was found to depend on the number of phenolic hydroxyl groups in the molecule. Upon lowering the temperature from 40 degrees to -20 degrees C, the chiral selectivity of the system, as measured by the relative mobility difference, increased tenfold for the amines with two vicinal phenolic hydroxyls, whereas the increase was insignificant for those having no phenolic hydroxyl groups. The complex formation constants of three amines which have the same molecular structure but the number of phenolic hydroxyl groups were determined at different temperatures and the thermodynamic parameters as well as compensation temperatures for the process were evaluated. Whereas the compensation temperature was 690 K for the amine without phenolic hydroxyl group, it was < 400 K for the amines with one or two phenolic hydroxyl groups. The difference in the compensation temperatures indicates that the intrinsic mechanisms of their complexation with the chiral selector are not the same; this may account for the discrepancies observed in the temperature dependency of the chiral selectivity. The enthalpy change per phenolic hydroxyl group was 2.5 kcal mol(-1), which compares favorably with the typical value for a single hydrogen bond. Therefore, when the amines have phenolic hydroxyl groups, the strong increase in chiral selectivity with decreasing temperature may be due to enhanced H-bonding between the cyclodextrin and the phenolic hydroxyls under the conditions employed in this study.

Biogenic Amines↗
PubMed2003

In-column field-amplified sample stacking of biogenic amines on microfabricated electrophoresis devices.

A novel method for performing in-column field-amplified sample stacking (FASS) in chip-based electrophoretic systems is presented. The methodology involves the use of a narrow sample channel (NSC) injector. NSC injectors allow sample plugs to be introduced directly into the separation channel, and subsequent stacking and separation can proceed without any need for leakage control. More importantly, stacking and separation occur in a single step negating the requirement for complex channel geometries and voltage switching to control sample plugs during the stacking procedure. The chip is composed of six paralleled systems. Using the NSC injector design, the number of reservoirs in the multiplexed chip is reduced to N + 2, where N is the number of paralleled systems. This design feature radically reduces the complexity in chip structures and associated chip operation. The approach is applied to the analysis of fluorescently labelled biogenic amines affording detection at concentrations down to 20 pM.

Biogenic Monoamines↗
PubMed2005

Enzymatic sensitivity enhancement of biogenic monoamines on a chip.

Detection of biogenic monoamines in nanomolar concentrations is of great importance for probing the brain chemistry and for their analytics in biological fluids. The sensitivity enhancement of amperometric detection of neurotransmitters (NTs) and their metabolites after their electrophoretic separation on a microchip is presented and is based on coupled enzymatic reactions. The current response of the analyte is amplified by cyclic oxidation on a gold electrode mediated by reduced nicotinamide dinucleotide coenzyme and glucose oxidase enzyme present in the electrophoresis buffer. Using this approach, detection limits of about 10 nM for NTs and their metabolites can be reached.

Biogenic Monoamines↗
PubMed2003

Using capillary isotachophoresis for the determination of biogenic amines and D-isocitric acid in food products.

This paper presents results achieved in the determination of biogenic amines in various food products and quality evaluation of some commercial orange juices by capillary isotachophoresis. The highest amount of histamine was determined in frankfurters (146.75 mg x kg(-1)); the content of tyramine was either under detection limit of method or it was present in very low concentrations. The highest amount of cadaverine was determined in Karicka cheese (666.36 mg x kg(-1)). The limit of determination was 1.59 mg x kg(-1) for histamine and 1.25 mg x kg(-1) for tyramine. The recovery of method ranged from 95.4 to 104.9%. Surprisingly it was found that many organge juice samples did not reach required values according to the Code of Practice. The lowest ratio of citric to D-isocitric acids was found in Happy day juice (44.1). Limit of determination was 1.62 mg x dm(-3) for citric acid and 2.00 mg x dm(-3) for D-isocitric acid. The recovery of the method ranged from 89 to 96.5%.

Beverages↗
PubMed1985

Biogenic amines and some metals in brain of cadmium-exposed diabetic rats.

Diabetic rats (alloxan diabetes) were exposed to cadmium (2 mg kg-1 i.p.) daily for 21 days to investigate the levels of blood glucose, biogenic amines and iron, copper, zinc and cadmium in the brain. Cadmium exposure to diabetic rats produced a significant exacerbation in the hyperglycemic effect and accumulation of cadmium in the blood compared with that observed after diabetes or cadmium exposure alone. The elevation in the levels of brain dopamine and 5-hydroxytryptamine were also more pronounced in cadmium-exposed diabetic rats compared with either cadmium exposure or diabetes alone. Cadmium exposure to diabetic rats also produced significant changes in the concentrations of copper in the blood. These results indicated enhanced cadmium toxicity in diabetic rats.

Animals↗
PubMed2005

Influence of the biogenic amine tyramine on ethanol-induced behaviors in Drosophila.

The biogenic amine tyramine has been implicated in drug-induced behavior. The Drosophila inactive mutant is characterized by reduced tyramine and octopamine levels and is defective in cocaine sensitization. To test whether there is an overlap in the use of the amine neurotransmitter system in ethanol- and cocaine-induced behaviors, mutant analyses were extended to the phenotypic characterization of inactive and other mutants effecting the tyramine and octopamine neurotransmitter system. The inactive mutant displays increased ethanol sensitivity and is impaired in the initial startle response upon ethanol application. Furthermore, this mutant fails to regulate its alcohol-induced hyperactivity properly. In contrast to the defects seen after cocaine application, inactive mutants develop normal ethanol tolerance and sensitize to the locomotor activating effect of ethanol. The tyramine-beta-hydroxylase mutant (TbetaH) with increased tyramine and depleted octopamine levels displays normal ethanol sensitivity, a startle repression, and hyperactivates more in response to ethanol. In addition, TbetaH mutants fail to develop a tolerance to the hyperactivating effect of ethanol. Ethanol-induced sensitization does not seem to be impaired in either mutant, suggesting that tyramine is not required for this process. The comparative analysis of the phenotypes associated with inactive and TbetaH mutants suggests that the fine tuning of ethanol-induced hyperactivity can be correlated with different tyramine levels. Defects in other aspects of ethanol-induced behaviors might be due to different molecules or mechanisms.

Animals↗
PubMed1992

The components of the venom of a spider Scodra griseipes. 2. Structural information on biogenic amines using tandem mass spectrometry.

Biogenic amines, which are components of tarantula Scodra griseipes venom, are studied using tandem mass spectrometry. Their heptafluoropropionic (PFP) derivatives are ionized under electron impact and isobutane-chemical ionization. Daughter- and parent-ion mass spectra under collisionally activated dissociation conditions provide a more detailed study of such derivatives. Discrimination of di(PFP)amines and tri and tetra(PFP)amines is possible because of the presence of diagnostic ions induced by collision.

Biogenic Polyamines↗
PubMed1991

[3H]1-[2-(2-thienyl)cyclohexyl]piperidine labels two high-affinity binding sites in human cortex: further evidence for phencyclidine binding sites associated with the biogenic amine reuptake complex.

Previous work demonstrated two high-affinity PCP binding sites in guinea pig brain labeled by [3H]TCP (1-(1-[2-thienyl]cyclohexyl)piperidine): site 1 (N-methyl-D-aspartate [NMDA]-associated) and site 2 (dopamine-reuptake complex associated). The present study examined brain membranes prepared from various species, including human, for the presence of site 2, defined as binding in the presence of (+)-5-methyl-10,11-dihydro-5H-dibenzo [a, d]cyclohepten-5,10-imine maleate ((+)-MK801) minus binding in the presence of 10 microM TCP (nonspecific binding). Studies were conducted in absence of sodium which was found to be inhibitory to [3H]TCP binding. The results demonstrated detectable levels of site 2 in brain membranes of guinea pig, rabbit, pig, mouse, sheep, and human but not in the rat or chicken. Using human cortical membranes, site 2 was the predominant binding site. Detailed studies conducted with human cortical tissue showed that high-affinity dopamine (1-[2- [bis(4-fluorophenyl)-methoxy]ethyl]-4-(3-phenylpropyl)piperazine (GBR12909)], [1,2]benzo(b)thiophenylcyclo-hexylpiperidine (BTCP), and serotonin (fluoxetine) uptake inhibitors produced a wash-resistant inhibition of [3H]TCP binding to site 2, but not site 1. Preincubation of guinea pig brain membranes with BTCP was shown to produce an increase in the dissociation rate of [3H]TCP from PCP site 2. Structure activity studies with various uptake inhibitors showed that GBR12909, benztropine, fluoxetine, and BTCP have higher affinity for site 2 than for site 1. (+)-MK801, ketamine, and tiletamine were very selective for site 1, whereas dexoxadrol and TCP were moderately selective for site 1. These results suggest that human cortex possesses high-affinity PCP binding sites associated with biogenic reuptake binding sites, and that guinea pig brain, but not rat brain, may be an appropriate animal model for studying PCP site 2 in human brain.

Animals↗
PubMed1995

Modulatory effects of biogenic amines on adipokinetic hormone secretion from locust corpora cardiaca in vitro.

The control of the release of adipokinetic hormones from neurosecretory cells within the glandular lobes of the corpus cardiacum involving axons running through the paired nervus corporis cardiaci II is unclear. Cyclic-AMP (cAMP) is clearly a second messenger. The effects of four biogenic amines (octopamine, dopamine, tyramine, and serotonin) on the release of adipokinetic hormone-I were investigated in vitro. None had an effect on its own; they all potentiated the hormone release induced by cAMP-activating agents. Dopamine and serotonin were only present in the neurohemal part of the corpus cardiacum. Octopamine and tyramine were not detectable in the corpus cardiacum.

Animals↗
PubMed1998

The effect of biogenic amines and their analogs on carbohydrate metabolism in the fat body of the cockroach Blaberus discoidalis.

Several biogenic amines and their analogs were examined for stimulatory effects on glycogen phosphorylase activity and trehalose biosynthesis in fat body of the cockroach, Blaberus discoidalis. Octopamine and synephrine were the most potent activators of fat body phosphorylase; 10 muM octopamine being nearly as effective as the hypertrehalosemic hormone (HTH). Epinephrine, norepinephrine, and tyramine produced intermediate effects, whereas dopamine, 5-hydroxytryptamine, and melatonin had no effect. The fat body octopamine receptors appeared to be pharmacologically related to vertebrate alpha-adrenergic receptors and belonged to the Octopamine1 class receptor. In contrast to previous reports, synephrine also induced both phosphorylase activation and hypertrehalosemia as effectively as octopamine. Demethylchlordimeform, a formamidine insecticide structurally similar to octopamine, also strongly activated fat body phosphorylase, possibly by interaction with the octopamine receptor.

Amidines↗
PubMed2000

Noradrenaline, dopamine, serotonin: different effects of psychological stress on brain biogenic amines in mice and rats.

The effect of restraint stress on central neurotransmission was evaluated in mice and rats. Noradrenaline (NA), dopamine (DA) and serotonin (5-HT) levels and their primary metabolites were measured in discrete brain regions following exposure to stress. Mice and rats demonstrated a similar response to stress in some brain regions. Both species responded to stress with lower NA and 5-HT in the locus coeruleus compared to non-stressed controls. Dopaminergic activity, assessed by DA turnover, was elevated in the hypothalamus. While DA turnover was suppressed in the amygdala, 5-HT turnover was similarly elevated in both species. In most cases, however, there were differences in biogenic neurotransmission between mice and rats in response to stress. In particular, NA levels were suppressed by stress in the dorsal cortex of mice, but in the rats NA levels were decreased in the hypothalamus. While stress produced lower DA levels in the hypothalamus, DA levels demonstrated a marked increase in the amygdala of mice. Stress was also associated with a decrease in DA levels in the rat striatum and with an increase of DA turnover in the locus coeruleus of mice. On the other hand, 5-HT was suppressed in the mouse striatum and in the rat hypothalamus and amygdala, while 5-HT turnover was markedly decreased in the hippocampus and dorsal cortex of rats alone. In conclusion, the changes in the central neurotransmission which are evoked by stress appear to be species-specific in most cases, a fact which may trigger discrete alterations in homeostatic mechanisms.

Animals↗
PubMed1990

Ghosts of chromaffin granules accumulate biogenic amines according to a "pump and leak system" without contribution of carrier-mediated efflux.

Unidirectional inward transport into, accumulation by and loss of biogenic amines from ghosts of bovine chromaffin granules were studied to determine whether a carrier-mediated process contributes to the outward passage of amines across the granule membrane. In the presence of ATP-Mg2+, incubated ghosts (30 degrees C; pH 7.3) showed a reserpine-sensitive (IC50 2-5 nmol/l), unidirectional, inward transport of catecholamine (CA = 70% adrenaline/30% noradrenaline), 5-hydroxytryptamine (5-HT) and tyramine with different Km values (mumol/l: tyramine 2; 5-HT 5; CA 8) but with the same Vmax [20 nmol/(mg protein.min)] during the first 3 min of incubation. During longer incubation, the rate of unidirectional inward transport declined rapidly with time to about 30 to 40%, at which level it stayed nearly constant from 50 to 100 min of incubation. As the decline of unidirectional transport was independent of the amine accumulated in the ghosts, it is concluded that it reflects ageing of the membrane vesicles. During incubation for up to 100 min with CA, 5-HT or tyramine (10- to 30-fold Km) in the presence of ATP-Mg2+, the amine content of the ghosts increased, approaching a steady-state content (nmol amine/mg protein: CA 400-500, 5-HT 250, tyramine 60), which was negatively correlated with the lipid solubility of the amine (tyramine greater than 5-HT greater than CA), whereas the rate of approach to steady state (t1/2 in min: CA 20-30, 5-HT 7-10, tyramine less than 5) was positively correlated. Low concentrations of reserpine (greater than or equal to 25 nmol/l) caused net loss of amine from amine-loaded ghosts by inhibition of inward transport. However, reserpine did not reduce the fractional rate of loss (FRL) of CA-loaded ghosts induced by NH+4 or uncoupling agents. Accelerated exchange diffusion was not found to occur at the granule membrane, as addition of high concentrations of 5-HT or dopamine to CA-loaded ghosts did not result in a higher FRL of CA than did blockade of inward transport by reserpine. Analysis of steady-state kinetics revealed the following features of the granule transport. The approach to steady state (t1/2) was independent of the rate of inward transport. The steady-state amine content of ghosts approached a limiting value as the external concentration of the amine was increased; it was determined by the same kinetic constants (Km and the time-dependent Vmax) as found for the rate of carrier-mediated inward transport.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenosine Triphosphate↗
PubMed1983

Biogenic amines in the brain of the honeybee, Apis mellifera.

Fluorescence histochemistry with glyoxylic acid has been used in close conjunction with detailed anatomical studies (Mobbs 1982) to investigate the distribution of fluorogenic amines in the brain of the honeybee, Apis mellifera. In addition, the concentration and distribution of biogenic amines in the brain of the bee have been determined using highly sensitive radioenzymatic techniques and high performance liquid chromatography. The cerebral ganglia of the bee contain similar amounts of dopamine and serotonin, more dopamine than octopamine, and very low levels of noradrenaline. Slow fading green fluorescence, typical of catecholamines, was located throughout the cerebral ganglia, and was particularly intense in the central body and mushroom body neuropils. Results indicate that the fluorescence in the mushroom body neuropils is largely extrinsic in origin. Both dopamine and serotonin were detected in the calyces and alpha-lobe of the mushroom bodies, and in the antennal lobe. In the optic lobe, however, serotonin was found, but only low levels of dopamine were detected. Slow fading green fluorescence was replaced in the optic lobes by fluorescence which faded rapidly in the excitation light. The non-fluorogenic amine octopamine was found in the mushroom bodies and in the neuropils of the optic lobes, with the largest amounts of octopamine in the optic lobes associated with the neuropil of the medulla. The possibility that intrinsic neurones of the mushroom body neuropil are octopaminergic is discussed.

Animals↗
PubMed1987

Effect of long-term administration of manganese on biogenic amine levels in discrete striatal regions of rat brain.

The effect of long-term manganese exposure of rats on biogenic amine levels in striatal brain regions is described. Four groups of male Sprague-Dawley rats received manganese as MnCl2 continuously in the drinking water for 60, 100, 165 and 265 days, respectively. Discrete regions within the caudate-putamen were punched out. Dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acid, serotonin and 5-hydroxyindoleacetic acid were determined by high performance liquid chromatography with electrochemical detection. Rats exposed for 60 and 165 days showed significantly increased levels of dopamine and 3,4-dihydroxyphenylacetic acid in discrete regions of the dorsal caudate-putamen. The affected regions were possibly not identical in the two age groups but they were adjacently situated. These alterations were not found in rats exposed for 100 or 265 days.

Animals↗
PubMed1975

Effects of clozapine, thioridazine, perlapine and haloperidol on the metabolism of the biogenic amines in the brain of the rat.

The effects of clozapine, thioridazine, perlapine and haloperidol on the metabolism of the biogenic amines in the brain of the rat have been investigated. Haloperidol, perlapine and thioridazine induce catalepsy and enhance the turnover of DA in the striatum as indicated by the dose-dependent increase in the DA-metabolites, HVA and DOPAC. These effects are due to blockade of dopaminergic transmission, haloperidol being far more potent than perlapine or thiridazine. Clozapine differs from these agents in that it elevates the concentration of striatal DA. The increase of the concentrations of HVA and DOPAC by clozapine is not accompanied by development of catalepsy. Therefore, clozapine seems to influence striatal DA by a mechanism other than DA-receptor blockade. All four drugs enhance the turnover of NA in the brain stem. This effect is probably secondary to the blockade of NA-receptors. There was no correlation between the effects on NA-metabolism and the EEG-arousal inhibitory activities of these agents or their clinical antipsychotic effects. Clozapine increase the concentration of 5-HT and 5-HIAA in the brain. This effect was not seen with the other drugs. Perlapine seems to enhance the turnover of 5-HT, whereas haloperidol reduced the 5-HT concentration. Thioridazine appears to have no effect on the metabolism of 5-HT.

Animals↗