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PubMedDate not supplied

[The biogenic amine content of rat tissues in the postresuscitation period following hemorrhagic shock and the effect of the preparation semax].

LPO products were measured in plasma and biogenic amines (serotonin, adrenalin, noradrenalin) in tissues of rats in different periods after hemorrhagic shock provoked by taking blood and maintenance of arterial pressure at the level of 40 mm Hg for 1 hour. Resuscitation was conducted by administration of autoblood. It was found that splenic serotonin levels decreased on experiment day 7 and went up on day 28. On late experiment stages noradrenalin levels in the adrenals were high. Early after resuscitation the trend was noted to higher LPO products concentration in plasma and serotonin in the brain stem. Intravenous injection of semax prevented serotonin fall in the spleen on experiment day 7. It is suggested that biogenic amines, especially serotonin system, are involved in mechanisms of postresuscitation disorders, in cerebral defects in particular, through prolongation of secondary hypoxia early after hemorrhagic shock and activation of hypothalamo-hypophyso-adrenal system late after the shock.

Adrenal Glands↗
PubMedDate not supplied

Use of biogenic amines to evaluate spoilage in plaice (Pleuronectes platessa) and whiting (Merlangus merlangus).

Fish muscle decarboxylases generate biogenic amines during spoilage. We monitored spoilage in plaice and whiting by assaying biogenic amines represented by the amine index (AI), and by using expert assessors to determine a freshness index (FI) for each fish. First we characterized the assessor- and fish species-related effects on FI, and then we sought to correlate changes in AI and FI by statistical data analysis. We propose rejection limits on the basis of our findings.

Animals↗
PubMed1976

Uptake, localization and secretagogic action of some biogenic amines in the submandibular and pancreatic glands of the guinea pig.

The effects of noradrenaline, 5-hydroxytryptamine (5-HT) 5-hydroxyptophan (5-HTP), dopamine, L-DOPA and carbamylcholine on the secretion of amylase from guinea pig submandibular gland and pancreas were studied. Carbamylcholine stimulated both pancreatic and salivary gland amylase release, whereas the biogenic amines elicted amylase secretion only from the submandibular gland. L-DOPA and 5-HTP, the precursor amino acids of dopamine and 5-HT, were without effects. In both glands 5-HT and dopamine were accumlated to a greater extent than their precursor amino acids. The uptake of biogenic amines into acinar cells and their effects on amylase secretion are compared and dicussed in terms of receptor specificity.

5-Hydroxytryptophan↗
PubMed2000

Cocaine and antidepressant-sensitive biogenic amine transporters exist in regulated complexes with protein phosphatase 2A.

Presynaptic transporter proteins regulate the clearance of extracellular biogenic amines after release and are important targets for multiple psychoactive agents, including amphetamines, cocaine, and antidepressant drugs. Recent studies reveal that dopamine (DA), norepinephrine (NE), and serotonin (5-HT) transporters (DAT, NET, and SERT, respectively) are rapidly regulated by direct or receptor-mediated activation of cellular kinases, particularly protein kinase C (PKC). With SERTs, PKC activation results in activity-dependent transporter phosphorylation and sequestration. Protein phosphatase 1/2A (PP1/PP2A) inhibitors, such as okadaic acid (OA) and calyculin A, also promote SERT phosphorylation and functional downregulation. How kinase, phosphatase, and transporter activities are linked mechanistically is unclear. In the present study, we found that okadaic acid-sensitive phosphatase activity is enriched in SERT immunoprecipitates from human SERT stably transfected cells. Moreover, blots of these immunoprecipitates reveal the presence of PP2A catalytic subunit (PP2Ac), findings replicated using brain preparations. Whole-cell treatments with okadaic acid or calyculin A diminished SERT/PP2Ac associations. Phorbol esters, which trigger SERT phosphorylation, also diminish SERT/PP2Ac associations, effects that can be blocked by PKC antagonists as well as the SERT substrate 5-HT. Similar transporter/PP2Ac complexes were also observed in coimmunoprecipitation studies with NETs and DATs. Our findings provide evidence for the existence of regulated heteromeric assemblies involving biogenic amine transporters and PP2A and suggest that the dynamic stability of these complexes may govern transporter phosphorylation and sequestration.

Animals↗
PubMedDate not supplied

[The content of biogenic amines in canned fish from the Turkish market].

This paper describes the determination of biogenic amines in a number of canned fish of the Turkish market by means of HPLC. Over all 39 cans of sardine, tuna, sardel, mackerel, pelamide and trout were tested. The determination of agmatine, cadaverine, histamine, putrescine and tyramine was performed by HPLC with post column derivatization with ortho-phthaldialdehyde. Four samples contained higher amounts of biogenic amines (three sardine samples contained more than 1000 mg/kg histamine) while all other samples were acceptable. These results demonstrate the need of instrumental analyses in the quality control system of Turkish producers of canned fish. The quality of the products at least of some producers has to be improved, e.g. by cooperation between the official food control and the quality assurance system of the producers.

Animals↗
PubMed1975

[Role of brain biogenic amines in the central thermoregulatory mechanism of the rat (author's transl)].

Changes in rectal and skin temperatures following intraventricular injection of biogenic amines and related substances were investigated in rats. Intraventricular injection of norepinephrine in a small dose (6 mug) produced a slight elevation of rectal temperature, but in larger amounts (25-50 mug) resulted in a dose-dependent hypothermia which was associated with a marked rise of skin temperature. No change was observed in plasma free fatty acid and glucose levels and oxygen consumption after intraventricular injection of norepinephrine (25 mug). Intraventricular injection of imipramine and safrazine produced a slight fall in the rectal temperature. Norepinephrine-induced hypothermia was more pronounced in rats pretreated with safrazine and less in rats pretreated with alpha-methyl-p-tyrosine, as compared with that in controls. Intraventricular injection of 6-hydroxydopamine (0.75-250 mug) brought about a marked dose-dependent hypothermia. The second injection of 6-hydroxydopamine 5 days after the first injection had no effect on the body temperature. Norepinephrine injection 2 days after the second injection of 6-hydroxydopamine produced a more pronounced hypothermia than the change in control rats without pretreatments. Haloperidol did not affect the hypothermia induced by 6-hydroxydopamine. Intraventricular injection of dopamine and L-DOPA showed less effect that norepinephrine had. Intraventricular injection of phenoxybenzamine prior to norepinephrine blocked the hypothermia and skin temperature elevation which are normally observed following norepinephrine injection, while propranolol given in the same way showed less or no effect. Intraventricular injection of phenylephrine produced a dose-dependent hypothermia, whereas no dose-response relationship was obtained by isoproterenol. These results suggest that in the rat the hypothermic effect of norepinephrine injected intraventricularly is mediated by an action of central alpha-receptor. At high and low ambient temperatures hypothermia was similarly observed following intraventricular injection of 5-hydroxytryptamine (25 mug) as at normal room temperature. On the other hand, norepinephrine (25 mug) produced a rise in rectal temperature at high ambient temperature and a marked fall at low ambient temperature. The hypothermic effect of norepinephrine was not different between cold-adapted ones at room temperature. From the results the role of norepinephrine and other biogenic amines in the brain in thermoregulatory processes was discussed.

Adaptation, Physiological↗
PubMedDate not supplied

[The effect of iproniazid on biogenic amine levels, elaboration and reproduction of alimentary conditioned reflexes].

A study of the action of iproniaside on alimentary conditioning has shown that even its small doses (25 mg/kg) disturb the formation of the conditioned reaction, while large doses (200-250 mg/kg) do not disturb the reproduction of the conditioned reaction elaborated and stabilized before the administration of the drug. Hence, dissociated learning with the use of iproniaside is impossible. The applied doses of iproniaside result in an increased level of biogenic amines in the dopaminergic nigro-neostriate and reticulo-septal brain systems. It is therefore assumed that the effects of iproniaside on learning are due to its influence on the level of the CNS biogenic amines.

Animals↗
PubMed2005

[Acute antenatal hypoxia on different stages of embryogenesis changes the offspring behavior patterns and biogenic amine levels].

The effects of acute hypobaric hypoxia on the stages of progestation or beginning of organogenesis on biogenic amines levels in brain stem and cerebral cortex of their mature offspring as well as on their behavior, were investigated. It was shown that acute hypoxia applied in the period of embryonic organogenesis resulted in severe delayed changes in offspring spontaneous behavior and led to marked changes of biogenic amine levels, particularly expressed for dopaminergic system. Females subjected to antenatal hypoxia happened to be more sensitive to its influences than males.

Acute Disease↗
PubMed1991

Biogenic amines as biomarkers for neurotoxicity.

There has been a surge of interest over the past several years in the use of neurochemical endpoints to contribute to our understanding of the mechanism of action of neurotoxicants. In our present presentation, two biogenic amine systems were selected as examples of biomarkers for neurotoxicity. To investigate these neurochemical endpoints, two prototype neurotoxicants were evaluated in experimental animals. One agent, reserpine, was used to assess developmental neurotoxicity and administered prenatally, while the other, MDMA, was used in the adult animal. The neurochemical biomarkers measured were dopamine, serotonin, and their metabolite (DOPAC and 5-HIAA) concentrations by HPLC/EC and dopamine receptor binding by radioligand receptor techniques. A review of the background, experimental design, and results are presented in this article. Our findings indicate that components of the biogenic amine systems can be used as sensitive neurochemical biomarkers of neurotoxicity. These neurochemical biomarkers can be correlated with neuropathological and behavioral biomarkers to aid in the understanding of mechanisms of neurotoxicity.

3,4-Methylenedioxyamphetamine↗
PubMed1975

Action of biogenic amines injected intracerebrally on duration of hexobarbital-induced sleep in rats.

The influence of intracerebrally injected biogenic amines and cyclic AMP dibutyrate on duration of sleep induced with hexobarbital (50 mg/kg i.v.) in rats was studied. Duration of sleep was markedly prolonged by adrenaline, noradrenaline, dopamine, 5-hydroxydopamine and acetylcholine. Cyclic AMP dibutyrate injected 30 minutes before hexobarbital shortened time of sleep. The role of biogenic amines in hexobarbital-induced sleep is discussed.

Acetylcholine↗
PubMedDate not supplied

Rapid determination and confirmation of biogenic amines in tuna loin by gas chromatography/mass spectrometry using ethylchloroformate derivative.

A gas chromatography-mass spectrometry (GC/MS) method is described for the easy rapid determination and simultaneous confirmation of the biogenic amines putrescine (PUT), cadaverine (CAD), histamine (HTA), and spermidine (SPD) in fresh frozen tuna loin. The method can also be used to monitor tyramine (TYR). The method involves homogenization of fish tissue, extraction of biogenic amines into trichloroacetic acid solution, centrifugation, alkalization, and derivatization of supernatant with ethylchloroformate. All seafood species were fortified to contain 2.5, 5.0, 10.0, 12.5, and 25.0 microg/g (ppm) PUT, CAD, and SPD; and 10.0, 20.0, 40.0, 50.0, and 100.0 microg/g (ppm) HTA. Determination was based on standard curves for each analyte using peak areas with matrix standards equivalent to a concentration range bracketing the spike level. A set of 5 matrix controls (unfortified tuna tissue) was also analyzed; only endogenous SPD was found in all samples. The interassay average recoveries ranged from 57 to 79% across analytes and spike levels.

Animals↗
PubMed1991

The molecular mechanism of nondegranulative release of biogenic amines.

According to current teaching biogenic amines are released by exocytosis, i.e. by evacuation of amine storing vesicles or granules into the extracellular space. The release of transmitter amines is quantal, i.e. occurs in packs of transmitter molecules. These packs are assumed to be identical with vesicle contents, in other words, the smallest releasable quantum equals the amine content of one vesicle. However, there are experimental observations which do not fit in with this version of an exocytotic release theory. Observed quantitative discrepancies could be explained if the release mechanism allowed a fractional release of transmitter amine from several vesicles instead of the total evacuation of a few. The lack of adequate knowledge about the mechanisms of storage of biogenic amines within the vesicles has up til now rendered it difficult to envisage the machinery behind a fractional release of the amine content of a vesicle. In extensive in-vitro studies we have found that the matrices of amine storing granules (i.e. from mast cells, chromaffin cells and nerve terminals) show the properties of weak cation exchanger materials, carboxyl groups serving as amine binding ionic sites. When exposed to cations like sodium and potassium ions, the amines are released from their storage sites according to kinetics characteristic of weak cation exchangers. In vivo, amine release from cat adrenals on splanchnic nerve stimulation also occurs according to ion exchange kinetics. Histamine release from mast cells is considered to occur as the result of degranulation, i.e. the expulsion of histamine storing granules to the extracellular space, a typical example of exocytosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Glands↗
PubMedDate not supplied

[Regulation by biogenic amines of energy functions of mitochondria].

Biogenic amines (phenylethylamine, tyramine, dopamine, tryptamine, serotonin and spermine) decreased activities of the rotenone-insensitive NADH-cytochrome c reductase, the succinate cytochrome c reductase and the succinate dehydrogenase in incubation mixtures containing mitochondrial membranes and the monoamine oxidase inhibitors chlorgyline and deprenyl. Spermine exhibited its influences at lower concentrations as compared with other monoamines. The effect of monoamines depended on presence of hydroxyl group (or groups) in the aromatic ring which led to elevation of the inhibitory effects. Lysis of membranes by Triton X-100 prevented the inhibitory action of all the compounds studied on succinate dehydrogenase. Alterations in content of some biogenic amines under pathological conditions and especially in drug inhibition of the monoamine oxidases appear to influence the energy functions of mitochondria, possibly via changes in the surface charge of the membranes.

Animals↗
PubMed1990

[Biogenic monoamines in ovum cells and preimplantation embryos of mice].

Histofluorescence technique using glyoxylic acid revealed a specific fluorescence suggesting the presence of biogenic monoamines in early developmental stages of CBA x C57 Black mice. A yellow fluorescence observed in the blastomere surface from the stage of zygote up to that of four blastomere points to the presence of indole derivates. As development proceeds, the fluorescence increases and its colour becomes more and more green, which is characteristic of catecholamines. From the stage of eight blastomeres up to stage of blastocyst specific fluorescence is revealed in the cytoplasm. The inhibitors of monoamine oxidase, introduced into pregnant mice, markedly increased the specific fluorescence. An assumption is made of functional activity of biogenic monoamines in early mouse embryos.

Animals↗
PubMed1986

Effects of the ergot alkaloid elymoclavine on the level and turnover of biogenic monoamines in the rat brain.

The effect of the clavine alkaloid elymoclavine, isolated from Claviceps sp cp II, on the level and turnover of biogenic monoamines in several rat brain structures was studied. Elymoclavine administered intraperitoneally (i.p.) at a dose of 5 mg/kg significantly increased the dopamine (DA) level in the striatum and hypothalamus and enhanced the DA turnover in the striatum. A significant increase was also found in the level and turnover of noradrenaline (NA) in the hypothalamus. Elymoclavine exerted an opposite effect on the level and turnover of serotonin (5-HT) in these brain structures: the 5-HT level significantly declined and the 5-HT turnover slightly decreased in the striatum and hypothalamus. In the cerebral cortex elymoclavine significantly increased the 5-HT level. Although the stimulant effect on DA receptors appears to be a dominant element in the mechanism of action of elymoclavine, it seems that this ergot alkaloid is also characterized by a plurireceptor action. The present results suggest a certain role for the elymoclavine action on the level and turnover of brain biogenic monoamines in the mechanism of its different pharmacological effects.

Animals↗
PubMed1988

Effect of T-2 toxin on brain biogenic monoamines in rats and chickens.

Two experiments were conducted to determine the effect of T-2 toxin on brain biogenic monoamines and their metabolites. Male rats (180 g) and cockerels (28 day, 300 g) were orally dosed with T-2 toxin at 2.5 mg kg-1 body weight. In the first experiment, whole brains were collected 2, 6, 12, 24 and 48 h postdosing and analyzed for monoamines by high performance liquid chromatography with electro-chemical detection. T-2 toxin did not influence whole brain concentrations of monoamines in either species. In the second experiment, brains were collected 24 h postdosing, dissected into five brain regions, and analyzed for monoamines. T-2 toxin treatment resulted in increased serotonin and 5-hydroxy-3-indoleacetic acid in all brain regions of the rat. However, this was not seen in poultry where T-2 toxin treatment resulted in an increase in 5-hydroxy-3-indoleacetic acid, no alteration in serotonin concentration and a decrease in regional norepinephrine and dopamine concentrations. These results suggest that T-2 toxin influences brain biogenic amine metabolism and that there is an intraspecies difference in the central effects of this mycotoxin.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1989

Flavodilol: a new antihypertensive agent that preferentially depletes peripheral biogenic amines.

Flavodilol, ((+/-)-7-[2-hydroxy-3-(propylamine)-propoxy]flavone maleate), a new orally effective antihypertensive agent, extensively depleted catecholamines and serotonin in heart tissue of normotensive and spontaneously hypertensive rats (SHR). Dose-response studies demonstrated that greater than or equal to 75% depletion of cardiac norepinephrine (NE) was accompanied by marked blood pressure decline in SHR. In contrast, whole brain biogenic amine levels were decreased only by 15-20% after acute or chronic treatment with antihypertensive doses (35-75 mg/kg). Adrenal epinephrine (EPI) stores were unaffected by acute treatment, although chronic treatment for 18 days with an antihypertensive dose of 75 mg/kg flavodilol decreased EPI by 70%. Acute treatment also decreased serotonin content of spleen by 70-80%. In dogs, a cumulative oral dose of 40 mg/kg decreased catecholamines by greater than or equal to 50% in aorta and heart muscle. Although hypothalamic catecholamine stores appeared to be more susceptible to depletion by flavodilol than catecholamines in other brain regions, these changes did not appear functionally related to blood pressure decreases since analogs of flavodilol without antihypertensive properties produced equivalent or greater depletion of hypothalamic catecholamine stores. In vitro flavodilol promoted spontaneous and potassium-evoked release of dopamine from isolated striatal nerve endings (0.3 microM) and blocked uptake of NE by hypothalamus and hippocampal nerve endings (1 microM), suggesting that biogenic amine depletion in vivo may be caused by an interference with storage and release mechanisms. Despite structural features reminiscent of beta-adrenergic antagonists, flavodilol had low affinity for beta-receptors. Neither was there any inhibition of tyrosine hydroxylase. These findings suggest that the antihypertensive activity of flavodilol results, at least in part, from depletion of sympathetic stores of NE in heart and vascular tissues that moderate adrenergic transmission, thereby decreasing heart rate (HR) and prevailing vascular tone.

Adrenergic beta-Antagonists↗
PubMedDate not supplied

Mouse strain-dependent effect of amantadine on motility and brain biogenic amines.

The effect of amantadine hydrochloride, injected i.p. in 6 increments of 100 mg/kg each over 30 hr, on mouse motility and whole brain content of selected biogenic amines and major metabolites was studied in 4 strains of mice. These were the albino Sprague-Dawley ICR and BALB/C, the black C57BL/6 and the brown CDF-I mouse strains. Amantadine treatment produced a biphasic effect on mouse motility. The initial dose of amantadine depressed locomotor activity in all mouse strains studied with the BALB/C mice being the most sensitive. Subsequent amantadine treatments produced enhancement of motility from corresponding control in all mouse strains with the BALB/C mice being the least sensitive. The locomotor activity was decreased from corresponding controls in all strains studied, except for the ICR mice, during an overnight drug-free period following the fourth amantadine treatment. Readministration of amantadine, after a drug-free overnight period, increased motility from respective saline control in all strains with exception of the BALB/C mice where suppression of motility occurred. Treatment with amantadine did not alter whole brain dopamine levels but decreased the amounts of 3,4-dihydroxyphenylacetic acid in the BALB/C mice compared to saline control. Conversely, brain normetanephrine concentration was increased from saline control by amantadine in the BALB/C mice. The results suggest a strain-dependent effect of amantadine on motility and indicate a differential response to the acute and multiple dose regimens used. The BALB/C mouse was the most sensitive strain and could serve as the strain of choice for evaluating the side effects of amantadine. The biochemical results of brain biogenic amines of BALB/C mouse strain suggest a probable decrease of catecholamine turnover rate and/or metabolism by monoamine oxidase and a resulting increase in O-methylation of norepinephrine which may account for a behavioral depression caused by amantadine in the BALB/C mice.

3,4-Dihydroxyphenylacetic Acid↗