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PubMed1985

Biogenic amine/metabolite response during in-flight emergencies.

Urine excretion of epinephrine (E), norepinephrine (NE), dopamine (DA), serotonin (5HT) and the metabolites vanillylmandelic acid (VMA), 4-hydroxy-3 methoxyphenylglycol (MHPG), homovanillic acid (HVA), 3, 4-dihydroxyphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIAA) was determined for students (n = 19) and instructors (n = 21) involved in flying training in-flight emergencies. Timed urine samples were analyzed using high-performance liquid chromatography with electrochemical detection. Basal excretion rates were determined at a later date. Four indices showed significant alteration during the emergencies. Epinephrine and the sum of epinephrine plus norepinephrine increased, the ratio dopamine/norepinephrine decreased and the ratio norepinephrine/serotonin increased. Instructors and students differed only in that VMA and the sum VMA plus MHPG were higher in students. Among the emergencies monitored, smoke and fumes in the cockpit and mechanical problems caused the greatest stress responses.

3,4-Dihydroxyphenylacetic Acid↗
PubMedDate not supplied

[Concentration of biogenic amines in different brain structures of the rat adapted to chronic emotional stress].

The level of noradrenaline (NA), dopamine (DA), serotonin (5-OT), and that of 5-oxyindolacetic acid was studied in four brain structures of rats having endured acute or chronic immobilization emotional stress. In stress adapted animals, NA level was normalized in the hypothalamus and increased in the midbrain. DA level was increased in the hypothalamus, the midbrain and the medulla, and 5-OT level was increased in most of the structures studied. During above-mentioned shifts, the animals did not react by additional changes of NA, DA, and 5-OT levels to subsequent immobilizations. Observed rearrangements of turnover of neurotransmitters may be considered as one of the forms of manifestation of chronic emotional stress adaptation mechanisms.

Adaptation, Physiological↗
PubMed1985

[Effect of chronic exposure to nitrogen dioxide on biogenic amine levels in the brain of guinea pigs].

The experiment was carried out on male guinea pigs exposed to NO2 at a constant concentration of 0.1 ppm 24 h daily for 1, 2.5 and 6 months, or NO2 concentration was increased to 0.5 ppm twice daily, between 7:00 and 8:00 AM and 4:00 and 5:00 PM. After the exposure to NO2 was over the animals were killed by decapitation. The cranium was opened and the brain removed, and afterwards at 0 degrees C the left hemisphere was dissected into discrete areas which were then frozen on dry ice and weighed. The tissues were kept for 2-3 days at -20 degrees C, and afterwards the content of noradrenaline, 5-hydroxytryptamine and 5-hydroxyindole-acetic acid was estimated spectrofluorometrically in examined parts of the brain (thalamus--hypothalamus pons + medulla oblongata hippocampus, cortex frontalis). It was shown that the applied NO2 concentrations brought about slight and nonspecific alterations in the content of the investigated amines in guinea pigs' brain.

Air Pollutants↗
PubMedDate not supplied

The correlation between hypothalamic and midbrain biogenic amine content and the intensity of the emotional-defensive arousal in cats.

Changes in levels of noradrenaline (NA), dopamine (DA), serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in the medial hypothalamus and the midbrain central grey matter were determined and correlated with various levels of an emotional-defensive arousal in cats, evoked by an intrahypothalamic injection of carbachol. At the initial stage of excitation, 3 min after the injection of carbachol, the levels of NA, DA, and 5-HIAA in the medial hypothalamus increased, whereas in the central grey matter only the 5-HIAA level was elevated. During the maximum excitation (when the vocalization attained the peak level) the level of amines and 5-HIAA decreased in the medial hypothalamus; in the central grey matter only the levels of 5-HT and 5-HIAA declined. In the final phase of response, 5 min after the disappearance of vocalization, the 5-HT level in both structures increased. These results confirm the notion that the noradrenergic, dopaminergic and serotonergic systems participate in the central regulation of the emotional-defensive behavior, and show that the hypothalamus and midbrain play different roles in this regulation. The results also indicate that neurochemical mechanisms are similar in different types of emotional-defensive behavior. It seems that catecholaminergic systems play a stimulating role, while the serotonergic system inhibits the carbachol-induced defensive response.

Animals↗
PubMed1988

[Effect of the active immunization of rats with a serotonin-protein conjugated antigen on the content of biogenic amines in the brain and on behavioral reactions].

Active immunization of rats with conjugated antigen serotonin-protein decreased the level of serotonin and its metabolite 5-hydroxyindole-3-acetic acid in some brain structures as well as the level of dopamine in the hypothalamus. The induction of antibodies to serotonin decreased the horizontal movement activity in the animals.

Animals↗
PubMed1989

[Assay of biogenic amines by bioluminescence].

A bioluminescent procedure to measure noradrenaline and serotonin has been realized. The amines are oxidized by the monoamine oxidase of pig brain mitochondria. The NH3 generated in this reaction is directly measured by enzymatic reaction. The coenzyme of this last reaction is the NADH,H+ which is measured with a bioluminescent system: the FMN-oxidoreductase-luciferase. The extension to other amines is possible, it depends only of the specificity of the monoamine oxidase.

Biogenic Amines↗
PubMed1989

Effects of acute administration of medetomidine on the behaviour, temperature and turnover rates of brain biogenic amines in rodents and reversal of these effects by atipamezole.

The effects of acute administration of medetomidine in rodents were examined. Low doses (2.5 micrograms/kg) were anxiolytic, higher doses (10-100 micrograms/kg) sedating, and above 100 micrograms/kg medetomidine treated rats lost their righting reflex and were hypothermic. These higher doses of medetomidine inhibited the release of noradrenaline (NA), dopamine and serotonin in the central nervous system, inhibition of NA release being the most sensitive to medetomidine. All the above effects could be antagonized by administration of suitable doses of the alpha 2-antagonist, atipamezole, indicating that the actions of medetomidine were mediated via activation of alpha 2-adrenoceptors.

Adrenergic alpha-Agonists↗
PubMed1985

Biogenic amine alterations in limbic brain regions of muricidal rats.

Endogenous levels of serotonin, 5-hydroxyindoleacetic acid (5-HIAA), dopamine, 3-4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were measured in eight brain regions of muricidal (mouse killing) and non-muricidal rats. The regions studied were: the frontal cortex, caudate nucleus, septal area, hypothalamus, thalamus, amygdalae with pyriform cortex, anterior hippocampal formation, and brain stem. Serotonergic systems showed significant differences in discrete brain regions of muricidal rats as compared to those of non-muricidal rats. The differences were: significantly higher serotonin levels in the amygdalae and significantly higher 5-HIAA levels in the hippocampus of the muricidal rats. Serotonin levels were also higher in the hypothalamus of the muricidal rats, but the difference reached only borderline significance. Dopaminergic systems also showed significant differences in the septum of muricidal rats, where DOPAC levels were significantly lower than those of non-muricidal rats. The hippocampus of muricidal rats showed significantly higher dopamine levels. HVA levels in the hippocampus of muricidal rats were also higher but reached only borderline significance. These data suggest both central serotonergic and central dopaminergic involvements in rat muricidal behavior. The discrete brain regions which showed differences further suggest a limbic involvement.

3,4-Dihydroxyphenylacetic Acid↗
PubMedDate not supplied

[Histochemical reaction to biogenic amines of the nervous system of the larval and mature cestode Microsomacanthus microskrjabini].

Histochemical reaction with glyoxylic acid has revealed a specific fluorescence caused by the presence of indolamine (apparently serotonin) in the nervous system of larva and mature cestode. Fluorescence manifests itself in neurons and nerve fibres of the central ganglion and its commissure, in nerve cells of the proboscis, in longitudinal trunks and transverse commissures, and in the nerve elements connected with genital system.

Animals↗
PubMed1989

[The effect of exercise on the content of biogenic amines and acetylcholine of the blood in bronchial asthma patients].

The content of acetylcholine, histamine and the total amount of catecholamines were measured in blood of 33 patients with bronchial asthma, in 6 patients with preasthma and in 10 practically normal subjects before and after the use of graded exercise (bicycle ergometry). Subgroups of the patients with asthma of effort were singled out. In such patients, exercises resulted in a significant rise of histamine (p less than 0.05) or acetylcholine level (p less than 0.05). Histaminemia was mostly accompanied by an immediate obstructive response of the bronchi to exercise in the distal parts. In patients with a high acetylcholine content, obstruction of the large bronchi was mainly observed, with a slightly delayed response to exercise.

Acetylcholine↗
PubMed1989

[Effect of tuftsin on the orientation-exploratory behavior of normal white rats and against a background of pharmacologically induced disorders of the brain biogenic amine system].

The application of "hole board" method showed that the endogenic immunostimulator tetrapeptide tuftsin injected intraperitoneally in dose 0.3 mg/kg has a short-time stimulating action on the orienting reaction of rats in 5 min, though in 24 hours it suppresses the registered behavioral indexes. The pharmacological analysis of the above studied phenomenon showed that catecholaminergic and especially dopaminergic brain systems played the leading role in tuftsin effect. Tuftsin can normalize animals' behaviour disturbed by the pharmacological agents, which slightly influence the functioning of the brain dopaminergic system.

Animals↗