Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Tryptamines”

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.

At least 289 records · Page 16Linked to original sources
PubMed1995

alpha-Methylated tryptamine derivatives induce a 5-HT receptor-mediated head-twitch response in mice.

The two alpha-methylated tryptamine derivatives, 5- (5-FMT) and 6-fluoro-alpha-methyltryptamine (6-FMT), rapidly induced a head-twitch response (HTR) in mice. Two derivatives that lack the methyl group in their chemical structures, 5- (5-FT) and 6-fluorotryptamine (6-FT), did not induce the HTR. The induced HTR was depressed by pretreatment with cycloheptadine, p-chlorophenylalanine or fluoxetine, but was potentiated by 5,7-dihydroxytryptamine. Both 5- and 6-FMT increased brain 5-HT levels in hypothalamus, hippocampus, brainstem, striatum and cortex. 5-FMT decreased the levels of 5-hydroxyindoleacetic acid in those regions, but 6-FMT caused a significant decrease in only the hypothalamus and cortex. The two methylated derivatives inhibited mouse brain MAO-A activity more selectively than non-methylated derivatives. The results suggest that the HTR induced by 5- and 6-FMT may result from increased activity of central 5-HT neurons, probably due to increased 5-HT levels after MAO-A inhibition. This probably results in release of 5-HT with a concomitant increased interaction with postsynaptic 5-HT2 receptors. The present results also indicate the importance of the methyl group to selective MAO-A inhibition by the substrate-analogues tested, and the concomitantly induced animal behavior.

Animals↗
PubMed1981

Effect of minor tranquilizers, tryptamine antagonists and amphetamine on behavior punished by brain stimulation.

Earlier observations have shown that septal lesions released operant responding punished by foot-shock, but did not change behavior punished by electrical stimulation of the dorsal periaqueductal gray (DPAG) substance of the rat brain. In contrast, chlordiazepoxide facilitated both kinds of punished responding. In order to further study the mechanism of brain stimulation punishment, dose-response curves of two minor tranquilizers, chlordiazepoxide and pentobarbital, of two tryptamine antagonists, methysergide and cyproheptadine as well as of amphetamine on lever-pressing behavior of rats maintained by water reinforcement and punished by DPAG stimulation were determined. A multiple schedule with a variable-interval 2 min (VI 2) non-punished component and a continuous reinforcement (CRF) component in which every response was both rewarded and punished was used. Chlordiazepoxide and pentobarbital caused dose-dependent increases in punished responding. Unpunished VI response rates were also moderately increased by the minor tranquilizers. In contrast, neither methysergide nor cyproheptadine increased punished or unpunished responding at doses that have been previously shown to markedly release behavior punished by foot-shock, in the rat. Conversely, amphetamine, a drug that usually does not release responding punished by peripheral noxious stimulation, caused dose-dependent increases in responding suppressed by DPAG punishment without affecting VI response rate. These and previous results with septal lesions suggest that neither the septo-hippocampal system nor its serotonergic input from the mesencephalon mediate response suppression by DPAG electrical stimulation, in contrast to their active role in peripheral punishment. This difference may also explain the marked facilitatory effect of amphetamine on responding punished by brain stimulation shown by the present results.

Amphetamine↗
PubMed1984

Brain levels of 5-hydroxytryptamine, tryptamine and 2-phenylethylamine in the rat after administration of N-cyanoethyltranylcypromine.

Brain levels of 5-hydroxytryptamine (5-HT), tryptamine (T), 2-phenylethylamine (PEA) and monoamine oxidase activity at 5, 15, 30, 60, 120 and 240 min were determined in male Sprague-Dawley rats after intraperitoneal injection of the "pro-drug" N-2-cyanoethyltranylcypromine (CE-TCP, dose 0.1 mMole/kg). Analyses of 5-HT, T and PEA were performed on an electron-capture gas chromatograph with a capillary column. Activity of MAO-A and MAO-B was measured using a radiochemical method. Results indicate substantial inhibition of MAO in rat brain after intraperitoneal administration of CE-TCP, leading to elevated levels of 5-HT, T and PEA as early as 5 min after drug administration. Increases in brain levels of the trace amines T and PEA were much greater (approximately 40 and 100 times control levels, respectively) than with 5-HT (approximately 1.8 times control level) 240 min after administration of CE-TCP.

Animals↗
PubMedDate not supplied

The detection, identification and measurement of indole, tryptamine and 2-phenethylamine in putrefying human tissue.

Indole, tryptamine and 2-phenethylamine are putrefactive products which may be found in decaying human tissue. They may be identified by the data given found in decaying human tissue. They may be identified by the data given for infrared and ultraviolet spectrometry, fluorometry, thin layer and gas chromatography and mass spectrometry. Quantitative studies may be made using the gas chromatography method described. The rate of formation is affected by temperature and preservatives and may be prevented if necessary by the use of sodium fluoride. No relationship between the production of these materials (and alcohol) and time since the post-mortem examination could be established. The post-mortem examinations took place within 24 hours of death.

Ethanol↗
PubMed1993

The inhibition by indoleamines (tryptamine and serotonin) of ocular serotonin-N-acetyltransferase from Rana perezi is temperature-dependent.

Temperature effects on ocular serotonin N-acetyltransferase (NAT) kinetics characteristics from Rana perezi have been studied with respect to tryptamine and serotonin as substrates. Monoamine oxidase (MAO) activity does not interfere in NAT assay at acceptoramine concentrations used in NAT kinetics characterization from R. perezi retina. NAT shows an inhibition by high substrate (serotonin) concentration, which is temperature-dependent. NAT follows the Michaelis-Menten equation at low temperature, whereas at high temperatures (> 10 degrees C) an inhibition by serotonin is observed. This inhibition of NAT activity by serotonin could act as an amplification mechanism to increase daily melatonin rhythm amplitude in the retina of ectotherms.

Animals↗
PubMed1990

The effects of chronic trimipramine treatment on biogenic amine metabolism and on dopamine D2, 5-HT2 and tryptamine binding sites in rat brain.

1. Two week chronic administration of trimipramine increased the brain concentration and metabolism of dopamine and 5-hydroxytryptamine. 2. The treatment also produced a reduction in dopamine D2 and 5-hydroxytryptamine 5-HT2 receptors but no change in tryptamine binding was observed. 3. These findings suggest that trimipramine induces adaptive changes in dopamine and 5-hydroxytryptamine neurotransmission.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2004

The Meixner test in the detection of alpha-amanitin and false-positive reactions caused by psilocin and 5-substituted tryptamines.

STUDY OBJECTIVE: The Meixner test has been suggested to identify the presence of alpha-amanitin, one of the toxic compounds in Amanita mushrooms. We attempted to determine the detection limit of the Meixner test for alpha-amanitin and to determine the percentage of positive sample interpretation compared with other mushroom indole compounds. METHODS: This was a 2-part in vitro experiment. In part 1, we applied the Meixner test to a series of dilutions of alpha-amanitin (0 microg, 0.8 microg, 1.0 microg, 2.0 microg, and 4.0 microg) on telephone book paper, which were then presented to 5 blinded emergency physicians. We sought to determine the lowest amount of alpha-amanitin that was universally recognized as positive by the physicians (the detection limit). In the second part, 5 emergency physicians were presented simultaneously with 10 Meixner processed samples, including the mushroom indole compounds alpha-amanitin (2 microg and 10 microg), psilocin (20 microL and 60 microL of mushroom extract), 5-hydroxytryptamine (100 microg and 200 microg), and 5-methoxy-N,N-dimethyltryptamine (100 microg and 200 microg), as well as 2 negative controls (20 microL of water and methanol). We determined how likely these other indoles are to be mistaken for a positive alpha-amanitin Meixner reaction result by determining the percentage of positive sample interpretation for each compound and comparing them with the rate for alpha-amanitin. Fisher's exact test was used to determine any significant difference (P<.05) between the samples. RESULTS: The minimum amount of alpha-amanitin that was identified with 100% agreement by testers was 2 microg. For the second part, there was 100% agreement that psilocin gives a positive Meixner test (100% false positive) and a 35% recognition rate of the 5-substituted tryptamine compounds as a positive Meixner test. There was no statistical difference between the interpretation of alpha-amanitin and psilocin, suggesting the test is unable to differentiate between them. CONCLUSION: Although the Meixner test has a good detection limit for toxic amounts of alpha-amanitin, a positive Meixner reaction does not adequately distinguish between alpha-amanitin and other mushroom indoles.

Agaricales↗
PubMed2005

N-Alkylation of phenethylamine and tryptamine.

A clean and efficient method for the N-alkylation of tryptamine and phenethylamine, employing alcohols as the alkylating agents, has been developed. The reaction proceeds via catalytic electronic activation, involving an iridium catalyst which activates the alcohol by borrowing hydrogen from the substrate, returning it later in the catalytic cycle. Some examples of N-heterocyclisation have been performed employing a diol as the substrate.

Alcohols↗
PubMed2005

Tryptamine-based human beta3-adrenergic receptor agonists. Part 3: improved oral bioavailability via modification of the sulfonamide moiety.

The continued SAR investigation of tryptamine-based human beta(3)-adrenergic receptor (AR) agonists is reported. Prior efforts resulted in the identification of 2 as a potent beta(3)-AR agonist. Further modification of the left side arylsulfonamide portion in 2 provided compounds with good cell permeability, which have potent agonistic activity for beta(3)-AR. Cinnamylamine analog 16i exhibited an excellent agonistic profile in vitro and good oral bioavailability in rats.

Administration, Oral↗
PubMed2005

BGC20-761, a novel tryptamine analog, enhances memory consolidation and reverses scopolamine-induced memory deficit in social and visuospatial memory tasks through a 5-HT6 receptor-mediated mechanism.

Inhibition of 5-HT(6) receptors has been shown to improve memory consolidation, thus we tested whether a novel tryptamine analog with high affinity for 5-HT(6) receptors, BGC20-761 (5-methoxy-2-phenyl-N,N-dimethyltryptamine, PMDT), can enhance long-term memory. BGC20-761 (10 mg/kg i.p.) alone had no effect on social recognition in young rats, however, at doses of 5 mg/kg and 10 mg/kg i.p, BGC20-761 dose-dependently reversed a deficit of social recognition induced by scopolamine (0.4 mg/kg i.p.), an anticholinergic drug that impairs memory. BGC20-761 (10 mg/kg i.p.), scopolamine (0.2 mg/kg i.p.) or BGC20-761 + scopolamine had no effects on novel object discrimination in young rats (2 months). In mature rats (6 months), recognition of the novel object was improved following administration of BGC20-761. Scopolamine had no effect in object recognition. However, the addition of scopolamine disrupted the memory-enhancing effect of BGC20-761. Based on the high affinity of BGC20-761 for 5-HT(6) receptors, these cognitive enhancing effects are most likely mediated by 5-HT(6) receptor inhibition. The difference in effects of BGC20-761 in young vs. mature rats may reflect the status of memory consolidation in these different age ranges.

Animals↗
PubMed2006

Solvatochromic study of excited state dipole moments of some biologically active indoles and tryptamines.

Absorption and fluorescence spectra of some biologically active indole and tryptamine derivatives have been recorded at room temperature in solvents of different polarities. The interest in the photophysical properties of these molecules arises mainly from their utility in medicinal chemistry as neurotransmitter and hallucination/hallucinic agents. Excited-state dipole moments of these molecules have been estimated from solvent-dependent Stokes shift data using a solvatochromic method based on a microscopic solvent polarity parameter (ETN). All indoles show a substantial increase in the dipole moment upon excitation to the emitting state. These results are generally consistent with the Parametric Method 3 (PM3) calculations, and are found to be quite reliable in view of the fact that the correlation of the solvatochromic Stokes shifts with the microscopic solvent polarity parameter (ETN) is superior to that obtained using bulk solvent polarity functions.

Indoles↗
PubMed1988

Analysis of tryptamine at the femtomole level in tissue using negative ion chemical ionization gas chromatography-mass spectrometry.

An ultra sensitive method for the detection of tryptamine, an endogenous amine in mammalian neuronal systems, at the femtomole level has been developed using negative chemical ionization gas chromatography-mass spectrometry (NCI-GC-MS). The amine is converted into a perfluorinated spirocyclic derivative, e.g. 1-pentafluoro-2-methylenepyrrolidine-3-spiro-3'-(3H-indole) which is detected using selected-ion monitoring of the (M-2HF) ions of the endogenous and deuterated internal standard compounds. Two mass spectrometers were compared; they gave minimum detectable quantities from tissue samples of 40 pg (VG-7070F) and 0.9 pg (VG-70S) respectively. These detection levels are approximately 5-200 times lower than have been obtained by previous MS methods.

Animals↗
PubMed2002

2-Arylindoles as gonadotropin releasing hormone (GnRH) antagonists: optimization of the tryptamine side chain.

A series of 2-arylindoles containing novel heteroaromatic substituents on the tryptamine tether, based on compound 1, was prepared and evaluated for their ability to act as gonadotropin releasing hormone (GnRH) antagonists. Successful modifications of 1 included chain length variation (reduction) and replacement of the pyridine with heteroaromatic groups. These alterations culminated in the discovery of compound 27kk which had excellent in vitro potency and oral efficacy in rodents.

Administration, Oral↗
PubMed2003

Analysis of reducing carbohydrates by reductive tryptamine derivatization prior to micellar electrokinetic capillary chromatography.

A micellar electrokinetic capillary chromatography method for determination of low molecular weight carbohydrates (dp 1-2) with an unbound carbonyl group as in aldoses or other reducing carbohydrates has been developed. Reductive amination of aldoses on the carbonyl group using tryptamine introduced a chromophor system to the carbohydrates enabling their sensitive UV detection at 220 nm and identification based on the indole group using diode array detection. Twelve carbohydrates including pentoses (d-ribose, l-arabinose, and d-xylose), hexoses (d-glucose, d-mannose, and d-galactose), deoxy sugars (l-rhamnose and l-fucose), uronic acids (d-glucuronic acid and d-galacturonic acid), and disaccharides (cellobiose and melibiose) are included in the study, using d-thyminose (2-deoxy-d-ribose) as the internal standard. Detection of all 12 carbohydrates is performed within 30 min. Linearity with correlation coefficients from 0.9864 to 0.9992 was found in the concentration range of 25-2500 micromol/L for all carbohydrates; the relative standard deviation on the migration times was between 0.27 and 0.80 min, and limits of quantification and limits of determination were in the picomole range.

Carbohydrates↗
PubMed2004

Identification and occurrence of tryptamine- and tryptophan-derived tetrahydro-beta-carbolines in commercial sausages.

The identification and occurrence of tetrahydro-beta-carbolines were studied in different kinds of commercial sausages including cooked, fresh, dry-fermented, and ripened sausages, such as salamis and Spanish chorizo, salchichon, fuet, and morcilla, both smoked and unsmoked. Four compounds were identified in several sausages by high-performance liquid chromatography-mass spectrometry (HPLC-MS): 1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (1), 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid diastereoisomers (2a,b), 1,2,3,4-tetrahydro-beta-carboline (3), and 1-methyl-1,2,3,4-tetrahydro-beta-carboline (4). The latter two (3 and 4) are now reported for the first time in meat products. The presence and occurrence of tetrahydro-beta-carbolines were highly variable depending on each particular sample of sausage, and it did not follow a single specific pattern. The concentration range taken as a sum of the four carbolines varied from undetectable levels to 33 microg/g, with the highest content found in ripened, dry-fermented, and smoked sausages (salami, chorizo, and morcilla) and the lowest in cooked sausages (Frankfurt). Formation of tetrahydro-beta-carbolines might occur during elaboration and the ripening process from a chemical condensation between tryptophan or tryptamine and aldehydes (formaldehyde and acetaldehyde). Smoked samples had higher concentrations of formaldehyde-derived 1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (1) and 1,2,3,4-tetrahydro-beta-carboline (tryptoline) (3) than those unsmoked. Also, 1 and 3 were more concentrated in the outer part of the sausage, likely to be in contact with smoke. It is concluded that some dry-fermented and/or smoked sausages may be significant dietary sources of tetrahydro-beta-carbolines.

Aldehydes↗
PubMed1995

Computer-aided design and synthesis of 5-substituted tryptamines and their pharmacology at the 5-HT1D receptor: discovery of compounds with potential anti-migraine properties.

The design and synthesis of a series of novel 5-substituted tryptamines with pharmacological activity at 5-HT1D and other monoamine receptors is described. Structural modifications of N- and C-linked (principally hydantoin) analogues at the 5-position were synthesized and their pharmacological activities were utilized to deduce significant steric and electrostatic requirements of the 5-HT1D and 5-HT2A receptor subtypes. Conformations of the active molecules were computed which, when overlaid, suggested a pharmacophore hypothesis which was consistent with the affinity and selectivity measured at 5-HT1D and 5-HT2A receptors. This pharmacophore is composed of a protonated amine site, an aromatic site, a hydrophobic pocket, and two hydrogen-bonding sites. A "selectivity site" was also identified which, if occupied, induced sensitivity for 5-HT1D over 5-HT2A in this series of molecules. The development and use of the pharmacophore models in compound design is described. In addition, the physicochemical constraints of molecular size and hydrophobicity required for efficient oral absorption are discussed. Utilizing the pharmacophore model in conjunction with the physicochemical constraints of molecular size and log DpH7.4 led to the discovery of 311C90 (6), a new selective 5-HT1D agonist with good oral absorption and potential use in the treatment of migraine.

Animals↗
PubMed1993

Synthesis and serotonergic activity of 5-(oxadiazolyl)tryptamines: potent agonists for 5-HT1D receptors.

The synthesis and 5-HT1D receptor activity of a novel series of 5-(oxadiazolyl)tryptamines is described. Modifications of the oxadiazole 3-substituent, length of the linking chain (n), and the amine substituents are explored and reveal a large binding pocket in the 5-HT1D receptor domain. Oxadiazole substituents such as benzyl are accommodated without loss of agonist potency or efficacy. The incorporation of polar functionality on a phenyl or benzyl spacer group results in a 10-fold increase in affinity and functional potency. Optimal 5-HT1D activity is observed when the heterocycle is conjugated with the indole and the benzyl sulfonamides 20t and 20u represent some of the most potent 5-HT1D agonists known. Replacement of O for S in the heterocycle leads to a further increase in potency. Deletion of oxadiazole N-2 does not reduce activity, suggesting the requirement for only one H-bond acceptor in this location. The selectivity of these compounds for 5-HT1D receptors over other serotonergic receptors is discussed. Sulfonamide 20t shows > or = 1000-fold selectivity for 5-HT1D over 5-HT2, 5-HT1C, and 5-HT3 receptors and 10-fold selectivity with respect to 5-HT1A receptors. The functional activity of this series of compounds is studied and demonstrates high 5-HT1D receptor potency and efficacy comparable to that of 5-HT.

Animals↗