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PubMed1975

[Methods of the histochemical detection of biogenic amines (author's transl)].

Histochemical and ultrahistochemical methods for the demonstration of biogenic amines are investigated with regard to their efficiencies and limitations. For the purposes of the light microscopy fluorescent histochemical methods at present are sufficient. Hereby beta-arylethyl-amines and indolalkylamines are demonstrable with formaldehyde or glyoxylic acid whilst histamine is traceable with o-phthaldialdehyde. In this connection those chemical and physical conditions of this methods are shown, under which the demarcation and quantitative determination of the several amines is possible. Ultrahistochemically biogenic amines can be demonstrated by means of the chromaffine and the argentaffine reaction, the reaction with permanganate and the REINECKE-salt precipitation technique. Apart from the latter one, all these methods are based on an initially reaction between glutaraldehyde and amines. Thus these techniques might be founded on one and the same principle. Besides, the demonstration of adreanline as a secondary amine might be hindered also by the fact that the product of its reaction with glutaraldehyde is soluble in water. On the other hand the reaction product of primary amines with glutaraldehyde is insoluble in water. When using REINECKE-salt the correctly localizated precipitation of amines is the first step of the reaction. After that the treatment with glutaraldehyde is only serving for the fixation of the tissues. But the ultrahistochemical methods mentioned above altogether are showing a deficiency as far as they do not allow to make the several amines selectively visible. Therefore a quantitative ultrahistochemistry of biogenic amines is still impossible at present.

Biogenic Amines↗
PubMed1976

Anion and amine uptake and uncoupling in submitochondrial particles.

1. Unlike chloroplasts, submitochondrial particles are not uncoupled by nigericin + KCl or NH4Cl. Also the uncoupling effect of lipophilic anions is largely independent of the addition of weak bases. 2. Low concentrations of permeant anions cause a shift of the steady-state energy level rather than a cycle of energy utilization. The degree of inhibition of ATP synthesis by tetraphenylboron is larger than required for the uptake of the anion. 3. Lipophilic anions such as bromthymolblue, bromcresolpurple, and 8-anilino-1-napthalene sulphonate cause a pH-independent, 50% uncoupling in submitochondrial particles at concentrations of 3, 30 and 30 muM, respectively. The passive interaction of bromthymolblue and bromcresolpurple appears as a pH-dependent distribution between two pHases. ATP causes a pH-independent slight shift in the anion distribution, with negligible anion accumulation. 4. Addition of amines to energized submitochondrial particles results in two types of effects; uptake of amines and uncoupling. While in chloroplasts amine uptake and uncoupling are closely associated, this is not the case in submitochondrial particles. The uncoupling effect is observed only with lipophilic and not with hydrophilic amines, and the degree of uncoupling increases with the lipophilicity of the amines. The amine uptake, on the other hand, is accompanied by negligible uncoupling. 5. While the uptake of amines is dependent on the presence of non-permeant anions, such as Cl-, the uncoupling effect is independent of Cl-. Furthermore the amine uncoupling is markedly enhanced by lipophilic anions. 6. The view is discussed that the uncoupling effect of lipophilic anions and lipophilic amines in submitochondrial particles is due to a catalytic energy dissipation rather than to a stoichiometry energy utilization. The molecular mechanism of uncoupling presumably involves a cycling of charges after a perturbation of the membrane structure.

Amines↗
PubMed1975

[The evidence of biogenic amines with Reinecke-salt as a new principle of evidence of substances in the ultrahistochemistry (author's transl)].

Reinecke-salt (ammonium tetracyanato diamine chromate) is known as amine precipitating reagens in applied chemistry. Its amine precipitates can be demonstrated in electron micrographes. The amine reineckates are unable to diffuse and difficult to dissolve. Depending from that they are localized in the cells. From our findings received in the boundary layer between adrenal cortex and adrenal medulla, we conclude that there are no non-specific precipitations with other cell components caused by Reinecke-salt. It could be determined that the catecholamines are accumulated in the cells of the adrenal medulla in granular shape in a typical manner. In the adrenal medulla cells of Acomys cahirinus first investigated by us we found amine containing vesicles with a diameter of 200 to 250 nm. In the neighbouring cells of the adrenal cortex no precipitates were visable. In the adrenal cortex we noticed the mitochondria from the tubulus typ specific for this region. The assumption that Reinecke-salt is a specific amine precipitating substance able of forming localized amin precipitates was confirmed by these investigations. So the Reineck-salt precipitation of biogenic amines is a new method beside the known ones for the ultrahistochemical amine demonstration. In our method the precipitation of amines by Reinecke-salt is the first step followed later by the tissue fixation with glutaraldehyde.

Adrenal Cortex↗
PubMed1976

Carbon-11 labeled aliphatic amines in lung uptake and metabolism studies: potential for dynamic measurements in vivo.

In order to assess the potential utility of amines labeled with short-lived nuclides as agents for lung imaging and function studies in humans, a series of aliphatic amines (C4-C10 and C13) labeled with carbon-11 (T 1/2 = 20.4 minutes), which decays by the emission of body-penetrating radiation, has been used as a model for studying some basic parameters affecting amine uptake and metabolism by the lung and other tissues in mice. The lung uptake (percentage of dose per organ) of aliphatic amines at 1 minute increased from 2.18 +/- 0.13% for butylamine to 13.33 +/- 0.84% for tridecylamine. Partition coefficients (between n-octanol and pH = 7 buffer) were measured for the C4 through C10 amines and for octanoic acid and octanenitrile. Within the amine series, the partition coefficient correlated with lung uptake. A comparison of a series of compounds all having a carbon chain length of eight but with different functional groups (--NH2, --C=N, --CO2H, --OH) showed that the amino group as well as the relatively lipophilic alkyl group were required for lung specificity. The 11C-aliphatic amines were rapidly metabolized via monoamine oxidase (ultimately to 11CO2). Non-amine metabolites in blood and lungs at 5 minutes postinjection were 95 and 50%, respectively. Pretreatment of mice with iproniazid and with pargyline decreased 11CO2 excretion, and iproniazid significantly increased the radioactivity retained by the brain, lungs and liver at 15 minutes. The rate of 11CO2 excretion depended on carbon chain length (C4 less than C5 less than C6 greater than C7 greater than C8 greater than C9 greater than C10 greater than C13).

Amines↗
PubMed1978

Chlorination of benzidine and other aromatic amines an aqueous environments.

The fate of aniline, N,N-dimethylaniline and benzidine in chlorinated waters was investigated. Conditions were controlled to approximate the process chlorination of raw water supplies and wastewater secondary effluents. As the molar ratio, (Cl2)/(amine), was increased, amine depletions increased and leveled off at about (Cl2)/(amine) = 1. Depletions in distilled water with "free" chlorine were somewhat higher than those in activated sludge/secondary effluent with combined chlorine. For each amine the number and type of products appeared to be independent of the water matrix and the ratio, (Cl2)/(amine). For the monophenyl amines ring chlorination was a significant depletion pathway. Extended chlorination of aniline yielded a precipitated product, while the N-substituted amine, N,N-dimethylaniline did not yield a solid product. In contrast to the monophenyl amines, when benzidine (p,p'-diaminobiphenyl) was exposed to chlorinated waters, a solid product resulted immediately. Infra-red analysis of this product indicated a polymeric structure with no ring chlorination. GLC analysis of the chlorination supernatant showed no ring substituted isomers of benzidine.

Aniline Compounds↗
PubMed1977

Identification of two populations of biogenic amine-containg cells in the mouse lung.

Two distinct populations of fluorogenic amine-containing cells were observed in the lungs of nine-week old mice: one with an intense yellow emission, which possible indicates the presence of serotonin; and one emitting a yellow-green fluorescence, which probably indicates the presence of a catecholamine such as dopamine or norepinephrine. Simultaneous identification of two different fluorogenic amine-containing cells, without pre-administration of a precursor to that amine, has not previously been reported. Such evidence of amine-containing cells demonstrated the success of the perfusion-freezing technique and established that cellular storage of fluorogenic amines does occur in vivo under normal physiological conditions. The function of such amine-containing cells has not been established; however, their location and the known physiological effects of amines would suggest regional control of ventilation/perfusion of the lung.

Animals↗
PubMed1979

Modulatory role for biogenic amines in the cerebral cortex. Microiontophoretic studies.

In order to investigate the mode of action of biogenic amines in rat cerebral cortex, the unitary activity of spontaneously firing neurons and their excitatory response to acetylcholine (ACh) were examined using microiontophoretic administration of dopamine (DA), noradrenaline (NA) and serotonin (5-HT). The predominant effect of these biogenic amines on the spontaneous activity was a profound and prolonged inhibition of firing (2-4 min), which attained its maximum within 15-120 sec. This response was generally more abrupt in onset and of greater magnitude with NA and 5-HT than with DA. Most units inhibited by DA, NA and 5-HT also showed marked depression of their excitatory response to ACh when pretreated with these biogenic amines. With repetitive administration of ACh, it could be shown that the total duration of inhibition of ACh responses by DA and NA was not as prolonged as the inhibition of the spontaneous firing of the same cells. With 5-HT, the initial ACh responses of many neurons could be completely blocked, and this inhibitory effect lasted as long as the inhibition of spontaneous firing. In view of the anatomical data demonstrating a relative sparsity of monoamine nerve terminals in cerebral cortex, the strong inhibition induced by DA, NA or 5-HT may have reflected slow inactivation of the biogenic amines. However, it could also be indicative of underlying mechanisms of action dependent on metabolic changes. Indeed, the interaction between biogenic amines and ACh might imply a balance between the intracellular pools of cAMP and cGMP is directly or indirectly influenced by the biogenic amines and ACh, respectively. This hypothesis would not exclude other modes of local interaction between DA, NA, 5-HT and ACh, and appears compatible with the modulatory role of biogenic amines in cerebral cortex.

Acetylcholine↗
PubMed1975

Purification of 2-oxoaldehyde dehydrogenase and its dependence on unusual amines.

1. 2-Oxoaldehyde dehydrogenase was purified from sheep liver and gave one band on polyacrylamide-gel electrophoresis. 2. The enzyme was completely dependent for its activity on the presence of Tris or one of a number of related amines, all of general structure: (See article). When more than one R group was hydrogen no enzyme activity was observed. 3. Only one of these amines is known to exist in living tissues and large concentrations of all amines were required for maximum activity. L-2-Aminopropan-1-ol was the most effective amine on the basis of substrate Km and Vmax. values and the amine Km values. 4. The enzyme was activated by phosphate which lowered the Km values for methylglyoxal, amine and NAD+. 5. The pH optimum of the enzyme was 9.3 and there was no activity at pH values below 7.8. A search for activators that might produce activity at pH 7.4 proved unsuccessful. 6. The enzyme was inhibited by rather large concentrations of barbiturates (6-46 mM) and nitro-alcohol analogues of the activating amines (66-139 mM).

Aldehyde Oxidoreductases↗
PubMed1976

Kinetic effect of some aliphatic amines on yeast alcohol dehydrogenase.

Initial rate studies of ethanol oxidation catalyzed by yeast alcohol dehydrogenase (EC 1.1.1.1) were carried out in the presence of varying concentrations of aliphatic amines over the pH range from 8.0 to 10.5. Aliphatic amines either activate or inhibit the enzyme depending on whether the pH is greater or less than 9.5 suggesting that the protonated amines activate and the nonprotonated amines inhibit the enzyme. Aliphatic amines activate yeast alcohol dehydrogenase by decreasing Kb while they inhibit the enzyme by increasing both Ka and Kia. When both protonated and nonprotonated amines are present in solution, either overall activation or inhibition will be observed depending on the relative concentration of the two amine species.

Alcohol Oxidoreductases↗
PubMed1979

Amine content of vaginal fluid from untreated and treated patients with nonspecific vaginitis.

We examined the vaginal washings from patients with nonspecific vaginitis (NSV) to seek biochemical markers and possible explanations for the signs and symptoms of this syndrome. Seven amines were identified including methylamine, isobutylamine, putrescine, cadaverine, histamine, tyramine, and phenethylamine. These amines may contribute to the symptoms of NSV and may contribute to the elevated pH of the vaginal discharge. They may also be partly responsible for the "fishy" odor that is characteristic of vaginal discharges from these patients. Among the seven amines, putrescine and cadaverine were the most abundant and were present in all vaginal discharges from each of ten patients before treatment. These amines are produced in vitro during growth of mixed vaginal bacteria in chemically defined medium, presumably by decarboxylation of the corresponding amino acids. We hypothesize the anaerobic vaginal organisms, previously shown to be quantitatively increased in NSV, are responsible for the amine production, because metronidazole inhibited the production of amines by vaginal bacteria in vitro, and Haemophilus vaginalis did not produce amines. H. vaginalis did release high concentrations of pyruvic acid and of amino acids during growth in peptone-starch-dextrose medium, whereas, other vaginal flora consumed both pyruvic acid and amino acids in the same medium during growth. These findings suggest that a symbiotic relationship may exist between H. vaginalis and other vaginal flora in patients with NSV.

Amines↗
PubMed1976

Estimation of surface area and counterion binding characteristics in fatty amine monolayers from desorption kinetics.

The surface area per molecule of an un-ionized fatty amine is very similar to the surface area per molecule of an un-ionized fatty acid. Surface area increases with ionization in both fatty amine and fatty acid films. However, fatty amino cations have much smaller surface areas than the corresponding fatty acid anions. Thus counterion binding is stronger with fatty amine cations than with fatty acid anions. Surface area data show that counterion binding affinities for fatty amine cations decrease in the strong field sequence Cl- greater than Br- greater than I- greater than SCN-. Furthermore, surface areas in the presence of the most strongly bound counterions, Cl- and Br-, increase significantly with an increase in subphase ionic strength. These data are consistent with the formation of strong ion-pair bonds and their disruption with an increase in ionic strength. Fatty amine cations desorb as micelles with much lower relative diffusion coefficients than the corresponding fatty acid anions. Furthermore, relative diffusion coefficients for fatty amine cations are strongly dependent on the specific cation. These data show that fatty amine cations form larger micelles when they desorb in the presence of strongly bound counterions. Anions enhance the solubility of a fatty acid anion in the sequence Cl- less than I- less than SCN-, which is characteristic of chaotropic anions that disrupt water structure.

Amines↗
PubMed1975

Intracellular distribution of amines taken up by rat mast cells.

Mast cells isolated from rat peritoneal and pleural cavities were incubated in vitro with radioactively-labelled histamine (Hi), 5-hydroxytryptamine (5-HT), dopamine (DA), noradrenaline (NA), tyramine (TA), phenylethylamine (PhEA), trptamine (TrpA), ephedrine (Eph) or amphetamine (Amph). All these amines were taken up by the mast cells. The dose-response curves for the compound 48/80-induced release of endogenous Hi and for the various amines taken up by the cells were compared. The release curves for Hi, 5-HT, DA, NA and TA were found to be similar to that for endogenous Hi, while those for PhEA, TrpA, Eph and Amph were different from that for endogenous Hi. The uptake of Hi, 5-HT, DA, PhEA, TrpA and Eph into granules in mast cells was studied. Membrane-bound granules were obtained by sonication of mast cells incubated with the respective amine, followed by differential contrifugation. The amine content of these granules was then measured. Hi, 5-HT and DA were found to be mainly localized to the granules, while a smaller proportion of the PhEA, TrpA and Eph was found there, the rest being located extragranularly. The present results suggest that, when taken up by rat mast cells, even amines which are not endogenous to the cells are stored in the same way as the endogenous amines Hi and 5-HT.

Amines↗
PubMed1977

Polymers of biogenic amines.

Biogenic amines, with a primary amino group, were reacted with glutaraldehyde to form insoluble precipitates. These precipitates had distinctive ultrastructural features upon further reaction with osmic acid. When tested in vitro, they had biological activity and showed evidence that part of this biological activity was due to the large polymer of glutaraldehyde and amine. Experiments with isotope-labelled amines in the production of these precipitates showed that the precipitated polymers were not completely stable and that free amine was liberated from them. Since they were not stable, , they could not be used for the morphological localization of the amines as had been intended, but they may have some use as depot drugs or in the immunization of animals against these amines.

Animals↗
PubMed1976

Biogenic amines and affective disorders. A critical analysis.

The evidence linking biogenic amines and affective disorders is critically reviewed. Surveyed are studies on the level of biogenic amines and their metabolites in the brain, blood, urine and cerebrospinal fluid of patients with affective conditions; the effects of biogenic amine precursors, depletors and blockers on affective states and the action of present methods of treatment of these disorders on the level of biogenic amines. Reference is also made to the existence of various disease states where abnormalities of biogenic amines exist in the absence of affective disorders. The review fails to uncover convincing evidence that affective disorders are related to abnormal levels of biogenic amines. Reasons are outlined why the "catecholamine hypothesis" and related theories can neither be proven nor disproven with the available techniques.

5-Hydroxytryptophan↗