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PubMed1977

Studies on brain metabolism of biogenic amines.

1. In vitro models (synaptosones, electrically stimulated brain slices and monoamine oxidase (MAO) preparations have been used to identify the sites of action of nomifensine on brain monoamine metabolism. 2. Nomifensine potentiates neurotransmission in noradrenergic and dopaminergic synapses by blocking catecholamine uptake. 3. Nomifensine does not inhibit MAO and does not enhance the release of biogenic amines. 4. Studies on electrically stimulated brain slices suggest that nomifensine does not directly stimulate dopamine (DA) nor noradrenaline (NA) receptor sites. 5. 5-Hydroxytryptamine (5-HT) uptake is not inhibited at "therapeutic" concentrations of nomifensine. 6. Nomifensine differs from the tricyclic antidepressants by virtue of its effect on the dopaminergic system.

Animals↗
PubMed2006

Biogenic amine formation and microbial spoilage in chilled garfish (Belone belone belone)--effect of modified atmosphere packaging and previous frozen storage.

AIMS: To evaluate biogenic amine formation and microbial spoilage in fresh and thawed chilled garfish. METHODS AND RESULTS: Storage trials were carried out with fresh and thawed garfish fillets at 0 or 5 degrees C in air or in modified atmosphere packaging (MAP: 40% CO2 and 60% N2). During storage, sensory, chemical and microbial changes were recorded and histamine formation by isolates from the spoilage microflora was evaluated at 5 degrees C. Photobacterium phosphoreum was responsible for histamine formation (>1000 ppm) in chilled fresh garfish. The use of MAP did not reduce the histamine formation. Strongly histamine-producing P. phosphoreum isolates formed 2080-4490 ppm at 5 degrees C, whereas below 60 ppm was formed by other P. phosphoreum isolates. Frozen storage inactivated P. phosphoreum and consequently reduced histamine formation in thawed garfish at 5 degrees C markedly. CONCLUSIONS: Photobacterium phosphoreum can produce above 1000 ppm of histamine in chilled fresh garfish stored both in air and in MAP. Freezing inactivates P. phosphoreum, extends shelf life and markedly reduces histamine formation in thawed MAP garfish during chilled storage. SIGNIFICANCE AND IMPACT OF THE STUDY: At 5 degrees C, more than 1000 ppm of histamine was formed in garfish; thus even when it is chilled this product represents a histamine fish-poisoning risk.

Animals↗
PubMed1981

Decreased transmethylation of biogenic amines after in vivo elevation of brain S-adenosyl-l-homocysteine.

The ability of S-adenosyl-L-homocysteine (AdoHcy) to inhibit biologic transmethylation reactions in vitro has led us to explore the possibility of pharmacologically manipulating AdoHcy levels in vivo and examining the consequences of these alterations on the transmethylation of some biogenic amines. Swiss-Webster mice were injected intraperitoneally with different doses of adenosine (Ado) and D, L-homocysteine thiolactone (Hcy) and were killed at various times thereafter. S-Adenosyl-methionine (AdoMet) and AdoHcy concentrations were determined by using a modified isotope dilution-ion exchange chromatography-high pressure liquid chromatography technique sensitive to less than 10 pmol. Increasing doses of Ado + Hcy (50-1000 mg/kg of each) produced a dose-related increase in blood, liver, and brain AdoHcy levels. At a dose level of 200 mg/kg Ado + Hcy, AdoHcy levels were markedly elevated, with minimal concomitant perturbations of AdoMet. This elevation was maximal 40 min after giving Ado + Hcy, returning to control values within 6 h. Ado + Hcy treatment resulted in decreased activities of catechol-O-methyltransferase, histamine-N-methyltransferase, and AdoHcy hydrolase in vitro. The cerebral catabolism of intraventricularly administered [(3)H]histamine (HA) was decreased in a dose-related manner by Ado + Hcy treatment as evidenced by higher amounts of nonutilized [(3)H]HA in brain, concurrent decreases in [(3)H]methylhistamine formation, and decreases in the transmethylation conversion index. Steady state levels of HA also showed dose-related increases after Ado + Hcy treatment. It is concluded that injections of Ado + Hcy can markedly elevate AdoHcy levels in vivo, which can, in turn, decrease the rate of transmethylation reactions.

Adenosine↗
PubMed1984

Cerebrospinal fluid measurements suggest precursor availability and sex are involved in the control of biogenic amine metabolism in a primate.

Biogenic amine precursors and metabolites were measured in cisternal cerebrospinal fluid from 83 female and 55 male vervet monkeys. The results indicate that mean rates of 5-hydroxytryptamine, dopamine, and noradrenaline metabolism in the brain are higher in females than in males. They also suggest that under physiological circumstances tryptophan availability is involved in the control of brain 5-hydroxytryptamine synthesis while tyrosine availability is involved in control of both dopamine and noradrenaline metabolism. The similarities seen between our results on vervets and those seen with human cerebrospinal fluid suggest that the vervet is a useful primate to study.

Animals↗
PubMed1985

Effects of p,p'-DDT on the rat brain concentrations of biogenic amine and amino acid neurotransmitters and their association with p,p'-DDT-induced tremor and hyperthermia.

Male, Fischer strain 344 adult rats were given various doses (25-100 mg/kg) of p,p'-DDT by oral gavage, and levels of biogenic amines, their metabolites, and amino acid neurotransmitters, tremor activity, and rectal temperature were measured at several intervals (2, 5, 12, and 24 h) after dosing. Dose-related increases in rectal temperature and in tremor activity were observed at 50-100 mg/kg 12 h after dosing. Tremorigenic doses of DDT increased the 5-hydroxyindoleacetic acid (5-HIAA) level in hypothalamus, brainstem, and striatum, whereas doses of 75 and 100 mg/kg increased the 3-methoxy-4-hydroxyphenylglycol (MHPG) level in hypothalamus and brainstem and the 3,4-dihydroxyphenylacetic acid level in striatum. Six amino acids were assayed in the brainstem, hypothalamus, and striatum; aspartate and glutamate levels were increased only in brainstem at 25-100 mg/kg. No consistent changes in concentrations of taurine, glutamine, glycine, or gamma-aminobutyric acid were observed in any of the regions assayed. Time-related increases in rectal temperature were seen 2-12 h after dosing, and the presence of tremor was observed 5-12 h after dosing; for both the time of peak effect was at 12 h. The DDT-induced hyperthermia and tremor were associated with dose- and time-related increases in levels of 5-HIAA, MHPG, aspartate, and glutamate. It is suggested that an increase in the turnover rate of 5-hydroxytryptamine (5-HT) may be responsible for the DDT-induced hyperthermia, whereas increases in the metabolism of 5-HT and norepinephrine may be involved in the tremor.

Amino Acids↗
PubMed1989

Analysis of biogenic amines in bovine retina by gas chromatography-negative ion chemical ionisation mass spectrometry.

Biogenic amines in bovine retina have been identified and quantified by an extraction-derivatisation procedure involving their reaction with 3,5-di(trifluoromethyl)benzoyl chloride (DTFMBCl) in the aqueous phase followed by extraction into an organic solvent, hydrolysis of phenolic esters, and conversion of free hydroxyl groups to trimethylsilyl ethers. Subsequent analysis of these DTFMB-trimethylsilyl derivatives by gas chromatography-negative ion chemical ionisation mass spectrometry revealed that the molecular ion carried most (greater than 60%) 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 bovine retina are p-tyramine, dopamine, and 5-hydroxytryptamine.

Animals↗
PubMed1990

Analysis of acidic metabolites of biogenic amines in bovine retina and vitreous and aqueous humour by gas chromatography-negative ion chemical ionisation mass spectrometry.

Acidic metabolites of a number of biogenic amines have been identified and quantified by reaction with either acetic or propionic anhydride in the aqueous phase followed by extraction into ethyl acetate, esterification of carboxyl groups with ditrifluoromethylbenzyl bromide (DTFMBzBr), and then conversion of the remaining free hydroxyl groups to acetates. Subsequent analysis of these derivatives revealed that most (greater than 60%) of the ion current was carried by the ion resulting from the loss of DTFMBz from the molecular ion. This made the method highly specific and practical--limits of detection were established at approximately 200 pg with a potential limit of detection below the picogram level. This method establishes unequivocally that the metabolites of tyramine, dopamine, and adrenaline/noradrenaline (4-hydroxyphenylacetic acid, 3,4-dihydroxyphenylacetic acid, and dihydroxymandelic acid, respectively) are present in bovine retina and in vitreous and aqueous humour. In addition, high concentrations of the dopamine metabolite homovanillic acid were found in retina and vitreous, but not in aqueous humour. p-Hydroxymandelic acid, the acidic metabolite of p-octopamine/p-synephrine, was identified in vitreous and in aqueous humour.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2006

Evolution of malolactic bacteria and biogenic amines during spontaneous malolactic fermentations in a Greek winery.

AIMS: To study the population dynamics of indigenous malolactic bacteria in a Greek winery and to examine their potential to produce detrimental levels of biogenic amines (BA) under winemaking conditions. METHODS AND RESULTS: Although the wines studied were of different vintage, grape variety and enological characteristics, molecular typing of malolactic bacteria revealed only a low number of strains within the single-species populations of Oenococcus oeni that developed during spontaneous fermentations. Strain MF1, originating primarily from the vineyards surrounding the winery invariably predominated in almost all samples. HPLC analysis showed a slight increase in the BA, putrescine, tyramine and phenylethylamine after malolactic conversion, while histamine, methylamine and ethylamine remained unaffected. No correlation could be established between the BA profiles and the bacterial compositions or the amino acid concentrations in wine samples studied. CONCLUSIONS: A certain regional bacterial flora is established in the winery that prevails in spontaneous malolactic fermentations (MLF) irrespective of the wine characteristics. In all cases, the BA content of the wines after malolactic conversion was within enologically acceptable levels. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on the malolactic bacteria occurring naturally in spontaneous MLF in Greek red wines and a preliminary assessment of their impact on wine safety in relation to BA.

Biogenic Amines↗
PubMed1976

Brain concentrations of biogenic amine metabolites in acutely treated and ethanol-dependent rats.

1 Mass fragmentography was used to measure whole brain concentrations of some of the major metabolites of tyramine, octopamine, dopamine and noradrenaline in acutely treated and in ethanol-dependent rats. 2 Treatments with ethanol, either acutely or chronically, failed to alter significantly brain concentration of p-hydroxphenylacetic and p-hydroxymandelic acid (metabolites derived from tyramine and octopamine respectively). The effect on catecholamine metabolites was marked and therefore suggests that ethanol is selective in its effect on central metabolism of biogenic amines. 3 Acute ethanol treatment significantly increased brain concentration of homovanillic acid (HVA), 3,4-dihydroxyphenylacetic acid (DOPAC) and 3-methoxy-4-hydroxyphenylglycol (MHPG). Vanilmandelic acid (VMA) was not affected. All four metabolites (HVA, DOPAC, MHPG and VMA) were increased in the brains of rats rendered dependent on ethanol while still intoxicated (blood ethanol levels above 200 mg/dl). In ethanol-dependent rats undergoing ethanol withdrawal syndrome (no ethanol present in blood), the brain concentrations of HVA and DOPAC were normal while those of MHPG and VMA continued to be elevated. 4 From the decline in the concentrations of HVA and DOPAC after 50 mg pargyline/kg in control rats and rats acutely treated with ethanol, it was concluded that ethanol has no effect on the transport of phenolic acids across the blood brain barrier. 5 No reversal in the metabolism of catecholamines from an oxidative to a reductive pathway, analogous to that produced by ethanol in the periphery, could be established in the brain. 6 The increase in catecholamine metabolite concentrations after ethanol treatment, either acute or chronic, were interpreted as manifestations of increases catecholamine turnover.

Animals↗
PubMed1980

Effect of low-dose lithium administration and subsequent withdrawal on biogenic amines in rat brain.

1 The effects of low-dose lithium administration (2 mEq/kg, daily) and its subsequent withdrawal have been examined with reference to changes in biogenic amine systems in several discrete regions of rat brain. 2 Increased levels of striatal tyrosine and midbrain tryptophan were found following lithium administration together with slight decreases in striatal tyrosine hydroxylase and midbrain tryptophan hydroxylase activities. Withdrawal resulted in a decrease in tyrosine content with increased tyrosine hydroxylase activity, whilst tryptophan levels and tryptophan hydroxylase activity were increased. 3 Lithium treatment and withdrawal resulted in altered levels of noradrenaline and dopamine, these changes being regionally variable. 3-Methoxy-4-hydroxyphenylglycol content was depressed in both treated and withdrawal rats as were 3,4-dihydroxyphenylacetic acid levels. Homovanillic acid decreased as a result of lithium treatment, but was greatly elevated in the withdrawal group. 4 5-Hydroxytryptamine content decreased in some brain regions following lithium treatment with return towards control values in withdrawal rats. 5-Hydroxyindoleacetic acid levels also displayed a regional variation as a result of lithium treatment and withdrawal. 5 The implications of these observations in elucidating the pharmacological effect of lithium treatment and its subsequent withdrawal are discussed.

Animals↗
PubMed1981

A study on the acute effect of amphetamine on the urinary excretion of biogenic amines and metabolites in monkeys.

1 The effects of an acute dose (3 mg/kg) of amphetamine on the urinary excretion of phenylethylamine (PEA), p-tyramine, their metabolites, catecholamine metabolites and p-hydroxymandelic acid, a major metabolite of p-octopamine were evaluated in the monkey. Amphetamine excretion was also measured. 2 Amphetamine was slowly eliminated from the body, being found in the urine at least six days after administration. 3 Amphetamine increased the excretion of PEA and decreased that of its major metabolite, phenylacetic acid (PAA). This pattern of changes is similar to that previously found in the urine of chronic schizophrenics. 4 The excretion of the dopamine metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC) was markedly reduced, that of vanilmandelic acid (VMA) remained unchanged while 3-methoxy-4-hydroxyphenylglycol (MHPG) was increased on the day of drug administration and persisted for at least a further six days. A similar extended effect on the excretion of p-hydroxymandelic acid (it was reduced) was also observed. 5 The excretion of p-tyramine but not its metabolite, p-hydroxyphenylacetic acid, was decreased by amphetamine during treatment and returned to normal levels six days later. 6 From the results obtained, it was concluded that amphetamine effects on behaviour cannot exclusively be attributed to its influence on catecholamines and that other biogenic amines may be involved. 7 Since PEA elicits many behavioural changes similar to those seen with amphetamine, and since amphetamine increases PEA excretion, we suggest that amphetamine may exert some of its behavioural responses through the release of PEA.

Amphetamine↗
PubMed1987

Effect of biogenic amines on phagocytosis in Tetrahymena thermophila.

Stimulation of phagocytosis by serotonin and catecholamines in Tetrahymena grown in proteose-peptone medium proved to be concentration dependent, the optimal concentrations being approximately 0.1 to 1.0 microM. The serotonergic antagonists, spiperone, and metergoline, also stimulated the process, whereas the beta- and alpha-adrenergic antagonists, propranolol, alprenolol, and ergocryptine, had no effect or inhibited phagocytosis. A wide variety of derivatives of the biogenic amines had no effect on phagocytosis, demonstrating the specificity of recognition mechanism for neurohormones in Tetrahymena. Such hormones act by at least two independent mechanisms, one for adrenergic agonists, another for dopamine. Presumably, recognition mechanisms for hormones in protozoa resemble in some respects those in multicellular organisms, therefore bespeaking a common origin.

Animals↗
PubMed1980

Purification of GABA on small columns of Dowex 50W; Combination with a method for separation of biogenic amines.

Elution of GABA has been included in the method for separation of biogenic amines on small Dowex 50W columns described by Atack & Magnusson (1978). After extraction with perchloric acid and neutralization to pH 3.0, the sample is passed through the column. 5-HIAA might thereafter be eluted as described by Lindqvist (1971). After washes with water and 8 ml of a 0.025 M sodium citrate buffer pH 4.5, GABA is eluted in 3 ml of a 0.05 M sodium citrate buffer pH 5.3-5.4. The elution of tryptophane and the above mentioned amines can thereafter be performed. The recovery of GABA from the column is 100%. Silica thin-layer chromatography of the GABA eluate gives only one ninhydrine positive spot with a Rf value identical to GABA standard. When the GABA eluate from a whole brain and spinal cord is run on an automatic amino acid analyser, only one peak is detectable, eluted in the same position as GABA standard. Fluorescence analysis of the GABA eluate gives similar values if a( ninhydrine, b) acetylacetone plus formaldehyde or c) fluorescamine is used to form the flurophore. The GABA values are identical whether the samples reacted with ninhydrine are diluted with water or copper tartrate. The GABA concentrations found in some parts of the rat brain are of the same order of magnitude as reported by other authors.

5-Hydroxytryptophan↗
PubMed1975

Biogenic amines in carotid body of adult and infant rats--a gas chromatographic-mass spectrometric assay.

A gas chromatographic-mass spectrometric method was used for the determination of biogenic amines in carotid body of adult and 10 days old rats. The method is ideally suited for this measurement since only small amounts of tissue were available (dry weight carotid body: adult 8.3 mug; infant 5.6 mug). In adult carotid body large amounts of dopamine (1 950 pmol/mg protein) and norepinephrine (1 140 pmol/mg protein) were found together with a comparatively small concentration of serotonin (505 pmol/mg protein). The carotid bodies of infant rats contained 1 065 pmol dopamine/mg protein and 410 pmol norepinephrine/mg protein. Epinephrine could not be detected. Surgical sympathetic denervation and chemical sympathectomy (6-hydroxydopamine) of adult carotid bodies did not significantly change the catecholamine content as compared to the controls. Reserpine depleted the catecholamines dosedependently. Administration of L-Dopa and pargyline (a monoamineoxidaseinhibitor) drastically increased the concentration of catecholamines. Treatment with a dopamine-beta-hydroxlase-inhibitor resulted in a decreased amount of norepinephrine without a simultaneous increase of dopamine. This may indicate that certain storage sites in this tissue may store dopamine while in other sites dopamine is a precursor of norepinephrine. Probably most of the dopamine and norepinephrine are stored in different cells.

Age Factors↗
PubMed1977

The ability of ATP-free granule material from bovine adrenal medulla to bind inorganic cations and biogenic amines.

Bovine adrenal medullary granules isolated by millipore filtration were depleted of CA and ATP by dialysis. The resulting material showed an ability to bind inorganic cations and biogenic amines in a concentration-dependent manner. The similarity of the uptake curves, the identical uptake maxima and the narrow pH range (between 4-7) over which the uptake of the inorganic and organic cations took place indicated a binding of these ions to common sites. In addition, the fact that all the uptake curves fitted the Rothmund-Kornfeld equation for cation exchangers corroborated the cation exchanger properties of the dialyzed granule material. The CA binding capacity corresponded to 20-30% of the normal CA content of bovine medullary granules.

Adenosine Triphosphate↗
PubMed1984

Incorporation of biogenic amines into phospholipids studied in two-phase-system.

Phospholipids (PL) from splenic nerves, splenic nerve granules, adrenal medullary granules and egg yolk were used as binding ligands for studies on uptake of various biogenic amines. Efficient uptake of catecholamine (CA) occurred at low ionic strength (about 2-5 mM) and at pH 6.8-7.7. This uptake was also a function of the amine concentration in the aqueous medium. At higher ionic strength (e.g. 128 mM K-phosphate buffer) an uptake still occurred, but to considerably less extent, apparently since the association/dissociation ability of the amines within the PL was a function of cation concentration in the aqueous media. Sucrose- and dextrose-induced increase in the osmolarity of the aqueous medium did not to any appreciable extent reduce the CA uptake. Scatchard plot indicated that only one type of binding sites was engaged when PL from splenic nerves was used. Using PL from splenic nerves the following affinity order was obtained for the amine tested: 5-HT greater than TA greater than DA greater than NA greater than IP greater than A. When PL from medullary granules was used the order was: DA greater than IP greater than A greater than or equal to NA. No or negligible uptake of Dopa and its metabolites Doma and Dopac occurred. When added to the aqueous medium, the cationic amphiphilic detergent CTAB induced some uptake of Doma and Dopac, but no a Dopa. However, CTAB considerably diminished the uptake of NA and the other amines. On the other hand, ionic (DOC) and anionic (SDS) detergents strongly increased the uptake of NA and other amines into PL. The nonionic Triton X-100 was without significant effect on uptake of NA. It is suggested that the binding ligands may be present in the dipolar head of the PL molecules, particularly in the lipid phosphate group. The lipid protein may also be partially involved since chromatographic experiments showed that the CA accompanied lipid phosphorus and lipid protein. Electrostatic or complex interaction of CA within the polar head group or in conjunction with lipid protein would constitute an amine storage with efficient association/dissociation capacity.

Adrenal Medulla↗
PubMed2003

In vitro characterization of ephedrine-related stereoisomers at biogenic amine transporters and the receptorome reveals selective actions as norepinephrine transporter substrates.

Ephedrine is a long-studied stimulant available both as a prescription and over-the-counter medication, as well as an ingredient in widely marketed herbal preparations, and is also used as a precursor for the illicit synthesis of methamphetamine. Ephedrine is related to phenylpropanolamine, a decongestant removed from the market place due to concerns that its use increased the risk of hemorrhagic stroke. Standard pharmacology texts emphasize that ephedrine is both a direct and indirect adrenergic agonist, activating adrenergic receptors both by direct agonist activity as well as by releasing norepinephrine via a carrier-mediated exchange mechanism. Chemically, ephedrine possesses two chiral centers. In the present study, we characterized the stereoisomers of ephedrine and the closely related compounds pseudoephedrine, norephedrine, pseudonorephedrine (cathine), methcathinone, and cathinone at biogenic amine transporters and a large battery of cloned human receptors (e.g., "receptorome"). The most potent actions of ephedrine-type compounds were as substrates of the norepinephrine transporter (EC50 values of about 50 nM) followed by substrate activity at the dopamine transporter. Screening the receptorome demonstrated weak affinity at alpha2-adrenergic and 5-hydroxytryptamine7 receptors (Ki values 1-10 microM) and no significant activity at beta-adrenergic or alpha1-adrenergic receptors. Viewed collectively, these data indicate that the pharmacological effects of ephedrine-like phenylpropanolamines are likely mediated by norepinephrine release, and although sharing mechanistic similarities with, they differ in important respects from those of the phenylpropanonamines methcathinone and cathinone and the phenyisopropylamines methamphetamine and amphetamine.

Adrenergic Agents↗