Fluorescence histochemistry of biogenic monoamines. A study of the capacity of various carbonyl compounds to form fluorophores with biogenic monoamines in gas phase reactions.
Explore the source record for details and available documents.
Acetates↗
SEARCH · Search PubMed
Results for “Biogenic Monoamines”
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Monoamine oxidase activities towards biogenic monoamines in several regions of rat brain.
Explore the source record for details and available documents.
Animals↗
Ontogenetic development of the monoamine oxidase activity and of the metabolism of biogenic monoamines in rat brain.
The article examines the ontogenetic development of the monoamine oxidase activity and of the metabolism of the dopamine, noradrenaline and serotonin in the brain of newborn, 10-day-, 20-day- and 2-month-old rats. Monoamine oxidase activity is determined using three substrates: tyramine, serotonin and beta-phenylethylamine. Monoamine oxidase A (substrate serotonin) and the total monoamine oxidase activity (substrate tyramine) are found to manifest identical development, their activity increasing quickly after birth, to reach constant values after the 10th day. The general course of the development during the first ten postnatal days shows that the post partum increase in the total monoamine oxidase activity in rat brain is predominantly due to monoamine oxidase A. Monoamine oxidase B (substrate beta-phenylethylamine) develops after the 10th postnatal day. Evidently monoamine oxidase A plays a decisive role for controlling the level of the biogenic monoamines in the young organism during the first days of the ontogenesis. Investigation of the changes in the content of dopamine, noradrenaline and serotonin in the age groups of the experimental animals chosen reveals a rapid increase in the dopamine and noradrenaline levels even during the first ten days of the ontogenesis. The increased total monoamine oxidase activity and the increased dopamine content correspond to its increased turnover rate during ontogenesis. The turnover rate of noradrenaline remains unchanged between the 10th and 20th postnatal days. The increasing serotonin level between the 20th and 60th post partum days corresponds to its increased turnover rate.
Aging↗
Effect of dietary T-2 toxin on biogenic monoamines in discrete areas of the rat brain.
Acute T-2 toxin treatments alter biogenic monoamine concentrations in the brain; however, these perturbations have not been well documented or demonstrated in feeding trials. In this study, the effect of dietary T-2 toxin on regional brain concentrations of biogenic monoamines and their metabolites was investigated in male rats fed a semi-synthetic diet containing 0, 2.5 or 10 ppm T-2 toxin for either 7 or 14 days. Reduction in feed consumption, feed efficiency and weight gain was observed in rats fed either 2.5 or 10 ppm T-2 toxin. This effect was transient in animals fed the 10 ppm T-2 toxin diet, with feed consumption, feed efficiency and weight gain improving significantly during wk 2. T-2 toxin affected brain biogenic monoamine concentrations. In the nucleus raphe magnus, serotonin, 5-hydroxy-3-indoleacetic acid and norepinephrine increased in a dose-dependent manner, and dopamine increased transiently. In the substantia nigra of rats fed 10 ppm T-2, epinephrine increased after 7 days and norepinephrine decreased after 14 days, when compared with controls. Dihydroxyphenylacetic acid concentrations in the paraventricular nucleus and medial forebrain bundle were lower in T-2 toxin-treated rats than in control animals. The observed effects of T-2 toxin on brain monoamines and the resulting neurochemical imbalance may account for the physiological manifestation of trichothecene intoxication.
Administration, Oral↗
Metabolism of biogenic monoamines in the ciliated protozoan, Tetrahymena pyriformis.
1. The three-dimensional HPLC system was used to detect the presence and determine the levels of biogenic monoamines, including precursor amino acids and metabolites, simultaneously in an extract of the ciliated protozoan, Tetrahymena pyriformis. 2. Representative biogenic monoamines, such as dopamine (DA), 5-hydroxytryptamine (5-HT), epinephrine (E) and kynurenine (KYN) were found to be synthesized in Tetrahymena and released into the growth medium. 3. The following metabolic pathways were suggested to be operative: (L-DOPA)-DA-(Epinine)-E-dihydroxyphenylethyleneglycol (DOPEG)-vanillylmandelic acid (VMA) and tyrosine-4 (TYR-4)-tyramine (TYRA)-hydroxyphenylacetic acid-4 (HPAC-4) in the case of catecholamines, and tryptophan (TRP)-5-HT and TRP-KYN-xanthurenic acid (XA) in the case of indolalkylamines. 4. As judged from the released metabolites, systems for generation of biogenic monoamines in Tetrahymena seem to be active during the logarithmic phase of its growth.
Animals↗
Fluorescence methods for the histochemical demonstration of monoamines. VII. Fluorescence studies on biogenic monoamines and related compounds condensed with formaldehyde.
Explore the source record for details and available documents.
Catecholamines↗
Computer-operated microspectrofluorimetry to identify formaldehyde-induced fluorophores of biogenic monoamines and precursor substances in models and tissue sections.
By means of a histochemical reaction using formaldehyde vapour (Falck and Owman 1965), biogenic monoamines and precursor substances, i.e., L-DOPA, dopamine, noradrenaline, adrenaline, 5-hydroxytryptophan and 5-hydroxytryptamine, may be converted into fluorophores with specific spectral characteristics, i.e., the emission spectrum, excitation spectrum and fading curve. The registration and correction of the spectral properties and changes induced by acidification with hydrochloric acid vapour or treatment with ammonia vapour, of these formaldehyde-induced fluorophores, are performed by an automated microspectrofluorimeter, developed by modification of a Leitz MPV 2 system. This work deals with the instrumental configuration and certain methodological features in order to identify the fluorogenic biogenic monoamines and precursor substances in models and tissue sections. Registrations of excitation peak values, for the first time extended to a wavelength range from 240-460 nm, are discussed, which enable the calculation of peak ratio values 410/260, 380/320, 320/260 or 385/315, suitable as identification parameters for formaldehyde-induced fluorophores of biogenic monoamines and precursor amino acids.
5-Hydroxytryptophan↗
Fluorescence of biogenic monoamines in the human dental pulp.
Biogenic monoamines in the adrenergic nerve terminals of the human dental pulp are demonstrated by the fluorescence method of Falck and Owman. Unmyelinated nerve fibers from nerves along alveolar blood vessels may enter the pulp, although pulp nerves are composed largely of myelinated fibers. The existence of a few sympathetic fibers is demonstrated by the fluorescence method, and possible drug effects are considered.
Biogenic Amines↗
[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↗
Effects of angiotensin II on biogenic monoamine uptake in the brain of nonhypoxic and hypoxic mice.
The effects of angiotensin II (ATII) administered intacerebroventricularly (i.c.v.) at a dose of 0.5 microgram per mouse on dopamine (DA), noradrenaline (NA) and 5-hydroxytryptamine (5-HT) high-affinity uptake in mouse forebrain during hypoxia (asphyxic and hemic) were studied. The influence of hypoxia on biogenic monoamine uptake was also investigated. It was found that DA uptake increased, NA uptake decreased and 5-HT uptake was unchanged after asphyxic hypoxia. Hemic hypoxia had no effect on biogenic monoamine uptake. ATII did not affect uptake of biogenic monoamines in normoxic mice after asphyxic and hemic hypoxia. The results suggest that ATII increases the susceptibility of animals to hypoxia through alterations in the brain high-affinity monoamine uptake.
Angiotensin II↗
Age-related changes of the effects of a group of nootropic drugs on the content of rat brain biogenic monoamines.
1. The changes in the levels of brain biogenic monoamines (BMAs) after chronic (7 days) treatment with piracetam, aniracetam and structural analogues of aniracetam (p-H, p-F, p-Cl, p-P and m-D) were studied in young and old rats. 2. An age-related significant decrease in the BMA content was established in old rats. 3. Most of the investigated compounds increased the level of one or other BMA in one or other of the brain structures studied. This elevation was predominantly established in old rats. 4. The present results and those from previous behaviour studies show that elevation of one or more of the BMA levels in one or more brain regions plays a beneficial role in the realization of their effects on the processes of learning and memory.
Aging↗
Predominant cytosolic distribution of serotonin in rat pineal gland in contrast to biogenic monoamine localization in midbrain and adrenal gland.
The subcellular distribution of serotonin and norepinephrine in the rat pineal gland was studied by tissue fractionation and compared with that of biogenic monoamines in the adrenal gland and midbrain. Homogenized tissues were fractionated by ultracentrifugation or by filtration through cellulose ester membranes. Most of the epinephrine (70-80%) and norepinephrine (62-82%) present in the adrenal glands was detected in the particulate fraction. The same distribution was found for serotonin (68.5%) and norepinephrine (59%) in the midbrain and for norepinephrine (62.5%) in the pineal gland. However, most of the serotonin in the pineal was found in the soluble fraction (89.5-98%). This suggests that the great majority of serotonin in the rat pinealocytes is cytosolic and thus is not stored in subcellular vesicles, in contrast to the biogenic monoamines in the midbrain or adrenal gland.
Adrenal Glands↗
Effects of the nootropic agents adafenoxate and meclofenoxate on brain biogenic monoamines in aged rats.
The effect of the nootropic agents meclofenoxate (Mf) and adafenoxate (Adf) on the content of biogenic monoamines in the frontal cerebral cortex, striatum, hypothalamus, and hippocampus of 22-month-old rats was studied. Mf and Adf were administered orally for seven days twice daily in a dose of 50 mg/kg weight. Both agents tested increased the content of serotonin (5-HT) in the cortex and striatum. Adf also raised the noradrenaline (NA) content in the cortex and hippocampus, lowering the dopamine (DA) level in the striatum. Comparison of the results obtained in the present study with the finding of earlier experiments of ours on 4-5-month-old rats revealed the following: 1. Biogenic monoamines (BMA) in the brain tend to decrease with ageing. 2. In addition to the unidirectional effects of Mf and Adf on the BMA content in the brain of both young and old rats, but in some cases there were also differences. 3. The comparison of the effects of Mf and Adf on the BMA content in the different brain regions with the changes in this content, characteristic of certain diseases, reveals prospects for selectivity in the application of these nootropic agents, which are generally rather similar in pharmacological characteristics.
Aging↗
Effects of beta-adrenoceptor blocker pindolol, calcium antagonist verapamil and their combination on retention in step-down- and shuttle-box-trained rats and on brain biogenic monoamines.
The effects of the beta-adrenoceptor blocker pindolol and the calcium antagonist verapamil administered alone or in combination on retention in step-down- and shuttle-box-trained rats and on the biogenic monoamine levels in the frontal cortex and hippocampus were examined. The chronic oral treatment with pindolol impaired retention in step-down- and shuttle-box-trained rats, decreasing the dopamine (DA) and noradrenaline (NA) levels and increasing the serotonin (5-HT) levels in the cortex and hippocampus. Verapamil did not influence retention in step-down- and shuttle-box avoidance situation and the biogenic monoamine levels in the frontal cortex and hippocampus. It should, however, be noted that the chronic oral treatment with verapamil completely abolished the retention-impairing effect of pindolol, restoring to normal DA, NA and 5-HT levels. These findings might be of interest to clinical practice and suggest the necessity for using a combination of beta-blockers with Ca2+ antagonists in case of prolonged treatment of cardiovascular diseases.
Adrenergic beta-Antagonists↗
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↗
Effect of some monoamine oxidase inhibitors on deamination of biogenic monoamines by rat liver mitochondrial monoamine oxidase.
Explore the source record for details and available documents.
Alkaloids↗
On the selective inhibition by some monoamine oxidase inhibitors of deamination of biogenic monoamines in vivo.
Explore the source record for details and available documents.
Animals↗
Effects of meclofenoxate on the level and turnover of biogenic monoamines in the rat brain.
The level and turnover of biogenic monoamines in some rat brain structures were determined after treatment with meclofenoxate at a dose of 50 mg/kg administered i.p. two times a day (9 a.m. and 5 p.m.) for 5 days. Meclofenoxate decreased dopamine (DA) turnover in the frontal cortex and striatum and highly increased it in the hypothalamus. The DA level significantly declined in the striatum, tended to decline in the cortex and significantly rose in the hypothalamus. The noradrenaline (NA) turnover and level in the cortex and striatum were decreased. Meclofenoxate decreased serotonin (5-HT) turnover in the cortex, striatum and hypothalamus and increased it in the pons. At the same time, the 5-HT level rose in the cortex, striatum and pons and declined in the hypothalamus. These results suggest the neurochemical basis of the psychotropic and neuroendocrine effects of meclofenoxate.
Animals↗