|
|
call loadScript javascripts\jsmol\core\package.js call loadScript javascripts\jsmol\core\core.z.js -- required by ClazzNode call loadScript javascripts\jsmol\J\awtjs2d\WebOutputChannel.js
|
| 5-Methoxytryptamine (5-MT, 5-MeO-T, or 5-OMe-T), also known as serotonin methyl ether or O-methylserotonin and as mexamine, is a tryptamine derivative closely related to the neurotransmitters serotonin and melatonin. It has been shown to occur naturally in the body in low levels, especially in the pineal gland. It is formed via O-methylation of serotonin or N-deacetylation of melatonin.
5-MT is a highly potent and non-selective serotonin receptor agonist and shows serotonergic psychedelic-like effects in animals. However, it is inactive in humans, at least orally, likely due to rapid metabolism by monoamine oxidase (MAO). The levels and effects of 5-MT are dramatically potentiated by monoamine oxidase inhibitors (MAOIs) in animals. |
|
Read full article at Wikipedia
|
| InChI=1S/C11H14N2O/c1-14-9-2-3-11-10(6-9)8(4-5-12)7-13-11/h2-3,6-7,13H,4-5,12H2,1H3 |
| JTEJPPKMYBDEMY-UHFFFAOYSA-N |
|
|
Mus musculus
(NCBI:txid10090)
|
Source: BioModels - MODEL1507180067
See:
PubMed
|
|
Brassica napus
(NCBI:txid3708)
|
Found in
leaf lamina
(BTO:0000719).
From MetaboLights
See:
MetaboLights Study
|
|
Homo sapiens
(NCBI:txid9606)
|
Found in
urine
(BTO:0001419).
See:
Geigy Scientific Tables, 8th Rev edition, pp. 165-177. Edited by Cornelius Lentner.
|
|
antioxidant
A substance that opposes oxidation or inhibits reactions brought about by dioxygen or peroxides.
Bronsted base
A molecular entity capable of accepting a hydron from a donor (Bronsted acid).
(via organic amino compound )
|
|
|
serotonergic agonist
An agent that has an affinity for serotonin receptors and is able to mimic the effects of serotonin by stimulating the physiologic activity at the cell receptors. Serotonin agonists are used as antidepressants, anxiolytics, and in the treatment of migraine disorders.
human metabolite
Any mammalian metabolite produced during a metabolic reaction in humans (Homo sapiens).
mouse metabolite
Any mammalian metabolite produced during a metabolic reaction in a mouse (Mus musculus).
5-hydroxytryptamine 2A receptor agonist
An agonist at the 5-hydroxytryptamine 2A ( 5-HT2A) receptor. An agonist at the 5-hydroxytryptamine 2B (5-HT2B) receptor.
5-hydroxytryptamine 2C receptor agonist
An agonist at the 5-hydroxytryptamine 2B (5-HT2C) receptor.
|
|
|
serotonergic agonist
An agent that has an affinity for serotonin receptors and is able to mimic the effects of serotonin by stimulating the physiologic activity at the cell receptors. Serotonin agonists are used as antidepressants, anxiolytics, and in the treatment of migraine disorders.
radiation protective agent
Any compound that is able to protect normal cells from the damage caused by radiation therapy.
neuroprotective agent
Any compound that can be used for the treatment of neurodegenerative disorders.
cardioprotective agent
Any protective agent that is able to prevent damage to the heart.
|
|
View more via ChEBI Ontology
|
2-(5-methoxy-1H-indol-3-yl)ethanamine
|
|
2-(5-methoxyindol-3-yl)ethylamine
|
ChemIDplus
|
|
3-(2-aminoethyl)-5-methoxyindole
|
ChemIDplus
|
|
5-MeOT
|
IUPHAR
|
|
5-MeOT
|
KEGG COMPOUND
|
|
5-methoxy-1H-indole-3-ethanamine
|
NIST Chemistry WebBook
|
|
5-Methoxytryptamine
|
KEGG COMPOUND
|
|
5-Mot
|
ChemIDplus
|
|
5-MT
|
IUPHAR
|
|
5MOT
|
ChemIDplus
|
|
mexamine
|
NIST Chemistry WebBook
|
|
O-methylserotonin
|
ChEBI
|
|
1220927
|
Gmelin Registry Number
|
Gmelin
|
|
145587
|
Reaxys Registry Number
|
Reaxys
|
|
608-07-1
|
CAS Registry Number
|
ChemIDplus
|
|
608-07-1
|
CAS Registry Number
|
NIST Chemistry WebBook
|
Tan DX, Hardeland R, Back K, Manchester LC, Alatorre-Jimenez MA, Reiter RJ (2016)
On the significance of an alternate pathway of melatonin synthesis via 5-methoxytryptamine: comparisons across species.
Journal of pineal research 61, 27-40 [PubMed:27112772]
[show Abstract]
Melatonin is a phylogenetically ancient molecule. It is ubiquitously present in almost all organisms from primitive photosynthetic bacteria to humans. Its original primary function is presumable to be that of an antioxidant with other functions of this molecule having been acquired during evolution. The synthetic pathway of melatonin in vertebrates has been extensively studied. It is common knowledge that serotonin is acetylated to form N-acetylserotonin by arylalkylamine N-acetyltransferase (AANAT) or arylamine N-acetyltransferase (SNAT or NAT) and N-acetylserotonin is, subsequently, methylated to melatonin by N-acetylserotonin O-methyltransferase (ASMT; also known as hydroxyindole-O-methyltransferase, HIOMT). This is referred to as a classic melatonin synthetic pathway. Based on new evidence, we feel that this classic melatonin pathway is not generally the prevailing route of melatonin production. An alternate pathway is known to exist, in which serotonin is first O-methylated to 5-methoxytryptamine (5-MT) and, thereafter, 5-MT is N-acetylated to melatonin. Here, we hypothesize that the alternate melatonin synthetic pathway may be more important in certain organisms and under certain conditions. Evidence strongly supports that this alternate pathway prevails in some plants, bacteria, and, perhaps, yeast and may also occur in animals. | Goh TB, Koh RY, Yam MF, Azhar ME, Mordi MN, Mansor SM (2015)
5-Methoxytryptamine reacts with natural food flavour to produce 6-methoxy tetrahydro-β-carbolines: in vitro investigation of their antioxidant and cytotoxicity properties.
Food chemistry 183, 208-216 [PubMed:25863630]
[show Abstract]
Various 6-methoxytetrahydro-β-carboline derivatives, namely BEN (6-methoxy-1-phenyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole), ANI (6-methoxy-1-(4-methoxyphenyl)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole), ACE (6-methoxy-1-methyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole) and VAN (2-methoxy-4-(6-methoxy-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-1-l)phenol), were prepared via the Maillard reaction using food flavours and 5-methoxytryptamine in aqueous medium and were investigated for their in vitro antioxidant and cytotoxicity properties. These derivatives were found to exhibit moderate antioxidant properties, based on a combination of DPPH, ABTS and FRAP assays. The results suggested that the Maillard reaction could be used to generate β-carboline antioxidants. It was beneficial that VAN showed the highest antioxidant activity but the least cytotoxic activities on non-tumourous cell lines of NIH/3T3, CCD18-Co and B98-5 using MTT assay. ACE, ANI and BEN showed mild toxicity at effective antioxidative concentrations derived from DPPH and ABTS assays. Furthermore, they are safer compared to 5-fluorouracil, cisplatin and betulinic acid on NIH/3T3, CCD18-Co and B98-5 cells. In conclusion, the antioxidant and cytotoxicity properties of 6-methoxytetrahydro-β-carbolines were demonstrated for the first time. | Haduch A, Bromek E, Sadakierska-Chudy A, Wójcikowski J, Daniel WA (2013)
The catalytic competence of cytochrome P450 in the synthesis of serotonin from 5-methoxytryptamine in the brain: an in vitro study.
Pharmacological research 67, 53-59 [PubMed:23098818]
[show Abstract]
Brain serotonin has been implicated in the pathophysiology of a wide spectrum of psychiatric disorders, as well as in the mechanism of action of psychotropic drugs. The aim of present study was to identify rat cytochrome P450 (CYP) isoforms which can catalyze the O-demethylation of 5-methoxytryptamine to serotonin, and to find out whether that alternative pathway of serotonin synthesis may take place in the brain. The study was conducted on cDNA-expressed CYPs (rat CYP1A1/2, 2A1/2, 2B1, 2C6/11/13, 2D1/2/4/18, 2E1, 3A2 and human CYP2D6), on rat brain and liver microsomes and on human liver microsomes (the wild-type CYP2D6 or the allelic variant 2D6*4*4). Of the rat CYP isoforms studied, CYP2D isoforms were the most efficient in catalyzing the O-demethylation of 5-methoxytryptamine to serotonin, but they were less effective than the human isoform CYP2D6. Microsomes from different brain regions were capable of metabolizing 5-methoxytryptamine to serotonin. The reaction was inhibited by the specific CYP2D inhibitors quinine and fluoxetine. Human liver microsomes of the wild-type CYP2D6 metabolized 5-methoxytryptamine to serotonin more effectively than did the defective CYP2D6*4*4 ones. The obtained results indicate that rat brain CYP2D isoforms catalyze the formation of serotonin from 5-methoxytryptamine, and that the deficit or genetic defect of CYP2D may affect serotonin metabolism in the brain. The results are discussed in the context of their possible physiological and pharmacological significance in vivo. | Verma P, Mathur AK, Masood N, Luqman S, Shanker K (2013)
Tryptophan over-producing cell suspensions of Catharanthus roseus (L) G. Don and their up-scaling in stirred tank bioreactor: detection of a phenolic compound with antioxidant potential.
Protoplasma 250, 371-380 [PubMed:22678752]
[show Abstract]
Five cell suspension lines of Catharanthus roseus resistant to 5-methyl tryptophan (5-MT; an analogue of tryptophan) were selected and characterized for growth, free tryptophan content and terpenoid indole alkaloid accumulation. These lines showed differential tolerance to analogue-induced growth inhibition by 30 to 70 mg/l 5-MT supplementation (LD(50) = 7-15 mg/l). Lines P40, D40, N30, D50 and P70 recorded growth indices (i.e. percent increment over the initial inoculum weight) of 840.9, 765.0, 643.9, 585.7 and 356.5 in the absence and, 656.7, 573.9, 705.8, 489.0 and 236.0 in the presence of 5-MT after 40 days of culture, respectively. A corresponding increment in the free tryptophan level ranging from 46.7 to 160.0 μg/g dry weight in the absence and 168.0 to 468.0 μg/g dry weight in the presence was noted in the variant lines. Higher tryptophan accumulation of 368.0 and 468.0 g/g dry weight in lines N30 and P40 in 5-MT presence also resulted in higher alkaloid accumulation (0.65 to 0.90 % dry weight) in them. High-performance liquid chromatography (HPLC) analysis of the crude alkaloid extracts of the selected lines did not show the presence of any pharmaceutically important monomeric or dimeric alkaloids except catharanthine in traces in the N30 line that was also unique in terms of a chlorophyllous green phenotype. The N30 line under optimized up-scaling conditions in a 7-l stirred tank bioreactor using Murashige and Skoog medium containing 2 mg/l α-naphthalene acetic acid and 0.2 mg/l kinetin attained 18-folds biomass accumulation within 8 weeks. Interestingly, the cell biomass yield was enhanced to 30-folds if 30 mg/l 5-MT was added in the bioreactor vessel one week prior to harvest. Crude alkaloid extract of the cells grown in shake flask and this bioreactor batch also showed the formation of yellow-coloured crystals which upon (1)HNMR and ESI-MS analysis indicated a phenolic identity. This crude alkaloid extract of bioreactor-harvested cells containing this compound at 50 μg/ml concentration registered 65.21, 17.75, 97.0, 100 % more total antioxidant capacity, reducing power, total phenolic content, and ferric-reducing antioxidant power, respectively, when compared with that of extracts of cells grown in shake flask cultures. The latter, however, showed 57.47 % better radical scavenging activity (DPPH) than the bioreactor-harvested cells. | Lissoni P, Messina G, Rovelli F (2012)
Cancer as the main aging factor for humans: the fundamental role of 5-methoxy-tryptamine in reversal of cancer-induced aging processes in metabolic and immune reactions by non-melatonin pineal hormones.
Current aging science 5, 231-235 [PubMed:23451999]
[show Abstract]
Aging and advanced cancer are characterized by similar neuroendocrine and immune deficiencies; the most important of them consist of diminished nocturnal production of the pineal hormone melatonin (MLT) and decreased production of IL-2. At present, however, it is known that the pineal gland may produce indole hormones other than MLT. The most investigated of them is represented by 5-methoxy-tryptamine (5-MTT), which may exert antitumor, anticachectic, and immunomodulating effects under experimental conditions, in addition to those effects produced by MLT itself. In an attempt to obtain some preliminary data in human subjects about the potential therapeutic properties of 5-MTT, three different studies of 5-MTT have been carried out in advanced solid tumor patients. The first study of MLT plus 5-MTT included 14 thrombocytopenic cancer patients who did not respond to MLT alone. In the second study we have compared the clinical efficacy of MLT plus 5-MTT in a group of 25 untreatable metastatic cancer patients to the results obtained in a control group of 25 cancer patients receiving MLT alone. Finally, the third study of MLT plus 5-MTT included 14 untreatable metastatic cancer patients who did not respond to MLT alone. In all of these studies, MLT and 5-MTT were given orally at the level of 20 mg/day in the evening and at 5 mg/day during the period of maximum light. A normalization of platelet number was achieved by MLT plus 5-MTT in 5 of 14 (36%) thrombocytopenic cancer patients who did not respond to MLT alone. The percentage of disease control obtained by MLT plus 5-MTT in untreatable metastatic cancer patients was significantly higher than that achieved by MLT alone (15/25 [60%] vs. 8/25 [32%], P < 0.05). Finally, the association of 5-MTT with MLT induced disease stabilization in 4 of 14 (29%) untreatable metastatic cancer patients who did not respond to MLT alone. | Gavrilov SS, Kulinskiĭ VI (2007)
[5-hydroxytryptamine and 5-methoxytryptamine increase tolerance to global cerebral ischemia].
Eksperimental'naia i klinicheskaia farmakologiia 70, 17-18 [PubMed:18318189]
[show Abstract]
In the global cerebral ischemia, 5-hydroxytryptamine (serotonin, 5-HT) and 5-methoxytryptamine (5-MT) produce a significant neuroprotector effect closely correlated with their hypothermic action. This expands the spectrum of cerebral functions controlled by 5-HT. At the same time, melatonin and 2-iodmelatonin, which are chemically (but not pharmacologically) close to 5-HT and 5-MT, do not exhibit such protective effects. Probably, an important role in the interaction with 5-HT receptors belongs to the NH2 group of the indole ring. | Cannizzaro C, Plescia F, Gagliano M, Cannizzaro G, Provenzano G, Mantia G, Cannizzaro E (2007)
Effects of pre- and postnatal exposure to 5-methoxytryptamine and early handling on an object-place association learning task in adolescent rat offspring.
Neuroscience research 59, 74-80 [PubMed:17601618]
[show Abstract]
A reduction in 5-HT1A receptor response enhances learning and memory performance in rats. Pre- and postnatal treatment with 5-methoxytryptamine (5MT), a non-selective serotonergic agonist, and early handling, reduce the number of 5-HT1A receptors in neonatal and pre-pubertal rat progeny. The aim of this study was to investigate in adolescent male rats the consequences of pre- and postnatal treatment with 5MT and its interaction with early handling on an object-place association learning task, the "Can test", a motivated, non-aversive, spatial/object discrimination task. Results show that a single daily injection of 5MT from gestational days 12 to 21 (1 mg/kg s.c.) and from postnatal days 2 to 18 to pups (0.5 mg/kg s.c.), increases the level of activity and the number of correct responses, and decreases the number of reference memory errors in the progeny as adolescent, compared to vehicle-treated rats. Similar effects are observed following a daily, brief, maternal separation of the pups from postnatal days 2 until 21. Furthermore, when 5MT-treated rats underwent to early handling procedure, the effects induced by 5MT increased handling-induced facilitation of the object-place association. These results suggest that pre- and postnatal treatment with 5MT enhances learning in the "Can test", probably due to a reduction in 5-HT1A receptors in the hippocampus. Whether the potentiation exerted by pre- and postnatal 5MT on early handling effects may be related to a further damping of 5-HT1A receptor response is not yet assessed; however, our data demonstrate that this association is able to induce long-term facilitative effects on spatial learning performance in a non-aversive spatial/object discrimination task in the adolescent rat offspring. | Lissoni P (2007)
Biochemotherapy with immunomodulating pineal hormones other than melatonin: 5-methoxytryptamine as a new oncostatic pineal agent.
Pathologie-biologie 55, 198-200 [PubMed:17451889]
[show Abstract]
Several experiments have demonstrated that pineal gland plays a physiological anticancer role. Melatonin (MLT), its most investigated hormone, is a natural anticancer agent. However, MLT would not be the only endocrine molecule responsible for the anticancer property of the pineal gland. In fact, another pineal indole hormone, the 5-methoxytryptamine (5-MTT), has appeared to exert in vitro an antitumour activity superior to that of MLT itself. Previous studies have already shown the therapeutic anticancer action of MLT in association with chemotherapy also in human neoplasms. This study was performed to evaluate the influence of 5-MTT at physiological doses (1 mg/day orally during light phase) on the efficacy of chemotherapy with cisplatin plus etoposide in advanced non-small cell lung cancer patients with respect to that obtained in patients treated by chemotherapy alone or chemotherapy plus pharmacological doses of MLT (20 mg/day orally during the dark phase of the day). The study included 100 patients, who were randomised to receive chemotherapy alone or in association with MLT or 5-MTT. The overall response rate achieved in both patients concomitantly treated with MLT or 5-MTT was significantly higher with respect to that obtained in patients treated with chemotherapy alone. Moreover, both MLT and 5-MTT significantly reduced some chemotherapy-related toxicities, namely thrombocytopenia and neurotoxicity. This preliminary study shows that less known pineal hormone 5-MTT may exert at low doses the same anticancer therapeutic effect in association with chemotherapy, which may be obtained by pharmacological doses of the most investigated pineal hormone MLT. | Römsing S, Bökman F, Bergqvist Y (2006)
Determination of melatonin in saliva using automated solid-phase extraction, high-performance liquid chromatography and fluorescence detection.
Scandinavian journal of clinical and laboratory investigation 66, 181-190 [PubMed:16714247]
[show Abstract]
A sensitive bioanalytical method for the determination of melatonin in saliva by solid-phase extraction (SPE), high-performance liquid chromatography (HPLC) and fluorescence detection has been developed and validated. Saliva was collected with a Salivette sampling device (Sarstedt) and a mixed-mode SPE column was used for the extraction of melatonin and internal standard (N-acetyl-6-methoxytryptamine) from the saliva. Chromatographic separation was performed using a HyPurity C18 LC column (150 x 2.1 mm) with mobile phase acetonitrile-ammonium hydrogen carbonate buffer, 0.015 M, pH 6.8 (23:77, v/v). Excitation and emission wavelengths were set to 285 nm and 345 nm, respectively. The within-day precision for the method at 50 pmol/L was 7.9 % and the between-day precision was 10.5 %. The limit of quantification was 50 pmol/L. | Kirchheiner J, Henckel HB, Franke L, Meineke I, Tzvetkov M, Uebelhack R, Roots I, Brockmöller J (2005)
Impact of the CYP2D6 ultra-rapid metabolizer genotype on doxepin pharmacokinetics and serotonin in platelets.
Pharmacogenetics and genomics 15, 579-587 [PubMed:16007002]
[show Abstract]
IntroductionCYP2D6 gene duplication causing ultrafast metabolism is one reason for failure in responding to CYP2D6-metabolized antidepressants. We studied the effect of the CYP2D6 duplication genotype on doxepin pharmacokinetics and platelet serotonin uptake and concentrations.MethodsPharmacokinetics of trans (E)- and cis (Z)-doxepin and N-desmethyldoxepin were analyzed after a single dose of 75 mg doxepin in 11 ultrafast metabolizers (UM), 11 extensive metabolizers (EM) and 3 poor metabolizers (PM), identified by genotyping for CYP2D6 alleles *2, *3, *4, *5, *6, *9, *10, *35, *41 and specific analyses to characterize gene duplication. Platelet serotonin concentrations were measured by HPLC.ResultsA trend for lower AUC of the active principle (sum of doxepin and N-desmethyldoxepin) in UMs versus EMs was detected (575 versus 1,000 nmol h/l, P=0.07), mainly due to the differences in desmethyldoxepin concentrations (P=0.003). Stereoselective analysis showed a significant effect of the UM genotype on (E)-doxepin pharmacokinetic parameters whereas those of (Z)-doxepin did not differ between the CYP2D6 genotype groups. The 75-mg doxepin dose had no effect on platelet serotonin concentration and uptake, but serotonin concentrations in platelets were significantly higher in UM in comparison to the EM and PM groups. At baseline, these concentrations were 462, 399, and 292 ng/10 platelets in UM, EM and PM (P<0.0001 for trend).ConclusionsAt the same dose, internal exposure to doxepin differed by more than ten-fold between the CYP2D6 genotype groups. CYP2D6 may have an effect on platelet serotonin explained by salvage pathways of 5-methoxytryptamine to serotonin mediated by CYP2D6; however, this finding requires further confirmatory experiments. | Bayari S, Ide S (2003)
Fourier transform infrared spectra and molecular structure of 5-methoxytryptamine, N-acetyl-5-methoxytryptamine and N-phenylsulfonamide-5-methoxytryptamine.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy 59, 1255-1263 [PubMed:12659894]
[show Abstract]
5-Methoxytryptamine (5-MT) is a potent antioxidant and has radioprotective action. N-acetyl-5-methoxytryptamine (melatonin, NA-5-MT) is a free radical scavenger and antioxidant, which protects against oxidative damage due to a variety of toxicants. The infrared spectra of 5-MT, NA-5-MT and new synthesized N-phenylsulfonamide-5-methoxytryptamine (PS-5-MT) were investigated in the region between 4000 and 400 cm(-1). Vibrational assignments of the molecules have been made for fundamental modes on the basis of the group vibrational concept, infrared intensity and comparison with the assignments for related molecules. X-ray powder diffraction patterns of molecules were also recorded. In order to optimize the geometries of the molecules, molecular mechanic calculations (MM3) were performed. Conformational analysis of 5-MT, NA-5-MT and PS-5-MT was also established by the using PM3 method. | Lissoni P, Bucovec R, Bonfanti A, Giani L, Mandelli A, Roselli MG, Rovelli F, Fumagalli L (2001)
Thrombopoietic properties of 5-methoxytryptamine plus melatonin versus melatonin alone in the treatment of cancer-related thrombocytopenia.
Journal of pineal research 30, 123-126 [PubMed:11270479]
[show Abstract]
Recent studies have shown that the hematopoietic system is under neuroendocrine control. In particular, thrombopoiesis has been proven to be stimulated by melatonin, and the pineal indole has been shown to be effective in the treatment of thrombocytopenia resulting from different causes. At present, however, there are no data concerning the possible thrombopoietic activity of pineal indoles other than melatonin. The present study was carried out to evaluate the effect of a concomitant administration of the pineal indole 5-methoxytryptamine in patients with cancer-related thrombocytopenia who did not respond to melatonin alone. The present study included 30 patients, who were randomized to receive melatonin alone (20 mg/day orally in the evening) or melatonin plus 5-methoxytryptamine (1 mg/day orally in the early afternoon). A normalization of platelet count was achieved in 5/14 (36%) patients treated with melatonin plus 5-methoxytryptamine and in none of the patients treated with melatonin alone (P < 0.05). Moreover, mean platelet number significantly increased only in the patients treated with melatonin plus 5-methoxytryptamine. This preliminary clinical study would suggest that 5-methoxytryptamine, a pineal indole, may also exert thrombopoietic activity. Further studies, however, will be required to establish whether 5-methoxytryptamine may play a direct thrombopoietic activity, or whether it may act by improving melatonin's efficacy. | Hardeland R (1999)
Melatonin and 5-methoxytryptamine in non-metazoans.
Reproduction, nutrition, development 39, 399-408 [PubMed:10420441]
[show Abstract]
Melatonin seems to be an almost ubiquitous substance, which has been detected not only in metazoans, but also in all major non-metazoan taxa investigated, including bacteria, dinoflagellates, euglenoids, trypanosomids, fungi, rhodophyceans, pheophyceans, chlorophyceans and angiosperms. Despite its vast abundance, little is known to date about its functions. Its presence is not necessarily associated with circadian rhythmicity, which is evident in yeast. Circadian rhythms of melatonin have been reported in non-metazoans only for several unicellular organisms and in one angiosperm. In dinoflagellates, which have been studied in the most detail, the effects on enzyme activities and on phase shifting are known, but the most spectacular actions concerning the stimulation of bioluminescence, changes in cytoplasmic pH and induction of resting stages, can be related to a metabolite of melatonin, the 5-methoxytryptamine; therefore, melatonin should also be considered as a source of other agonists. | Yamada J, Sugimoto Y, Yoshikawa T, Horisaka K (1997)
Hyperglycemia induced by the 5-HT receptor agonist, 5-methoxytryptamine, in rats: involvement of the peripheral 5-HT2A receptor.
European journal of pharmacology 323, 235-240 [PubMed:9128844]
[show Abstract]
The effects of the 5-HT receptor agonist, 5-methoxytryptamine, on plasma glucose levels were investigated in rats. 5-Methoxytryptamine induced a significant hyperglycemia above the dosage of 1 mg/kg. 5-Methoxytryptamine-induced hyperglycemia was antagonized by pretreatment with the 5-HT1 and 5-HT2 receptor antagonist, methysergide, or the 5-HT2A receptor antagonist, ketanserin, whereas the 5-HT3 and 5-HT4 receptor antagonist, tropisetron, and the 5-HT4 receptor antagonist, SDZ 205-557 (2-methoxy-4-amino-5-chloro-benzoic acid 2-(diethylamino) ethyl ester), showed no effect. In addition, the peripheral 5-HT2 receptor antagonist, xylamidine, reduced 5-methoxytryptamine-induced hyperglycemia. These results suggest that 5-methoxytryptamine-induced hyperglycemia is mediated by the peripheral 5-HT2A receptor, although it has a high affinity for the 5-HT4 receptor. Adrenodemedullation abolished the 5-methoxytryptamine-induced hyperglycemia. 5-Methoxytryptamine did not affect the blood levels of the pancreatic hormones, insulin and glucagon. The hyperglycemia induced by 5-methoxytryptamine was not affected by pretreatment with dexamethasone which inhibits corticosterone release. These results indicate that 5-methoxytryptamine-induced hyperglycemia is elicited by a facilitated adrenaline release from the adrenal gland. Therefore, it is suggested that the 5-HT2A receptor may be partly involved in the pharmacological effects induced by the 5-HT4 receptor agonist, 5-methoxytryptamine. | Geffard M, Dulluc J, Rock AM (1985)
Antisera against the indolealkylamines: tryptophan, 5-hydroxytryptophan, 5-hydroxytryptamine, 5-methoxytryptophan, and 5-methoxytryptamine tested by an enzyme-linked immunosorbent assay method.
Journal of neurochemistry 44, 1221-1228 [PubMed:3919158]
[show Abstract]
Antisera were raised against tryptophan, 5-hydroxytryptophan, 5-hydroxytryptamine, 5-methoxytryptophan, and 5-methoxytryptamine, by conjugating each molecule to bovine serum albumin and to human serum albumin via glutaraldehyde, in such a way as to preserve the original part. Antibody specificity was tested with the enzyme-linked immunosorbent assay method. The specificity of each anti-indolealkylamine-glutaraldehyde antibody was established with competition experiments by using an adsorbed immunogenic conjugate and indolealkylamines either free or conjugated with poly-L-lysine. The nonconjugated compounds were poorly recognized. In the same way, the nonreduced conjugates always appeared less immunoreactive than the reduced ones. Calculated from the specificity study of each antiserum, the cross-reactivity ratios were found to be smallest for the most immunoreactive conjugates. Thus, a specific immune response was defined for each compound belonging to the same metabolic pathway. |
|
