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1.
Cell Mol Neurobiol ; 40(2): 257-272, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31848873

RESUMO

Trace amine-associated receptors (TAARs) are a family of G protein-coupled receptors (GPCRs) that are evolutionarily conserved in vertebrates. The first discovered TAAR1 is mainly expressed in the brain, and is able to detect low abundant trace amines. TAAR1 is also activated by several synthetic compounds and psychostimulant drugs like amphetamine. Activation of TAAR1 by specific agonists can regulate the classical monoaminergic systems in the brain. Further studies have revealed that other TAAR family members are highly expressed in the olfactory system which are termed olfactory TAARs. In vertebrates, olfactory TAARs can specifically recognize volatile or water-soluble amines. Some of these TAAR agonists are produced by decarboxylation of amino acids. In addition, some TAAR agonists are ethological odors that mediate animal innate behaviors. In this study, we provide a comprehensive review of TAAR agonists, including their structures, biosynthesis pathways, and functions.


Assuntos
Aminas Biogênicas/metabolismo , Estimulantes do Sistema Nervoso Central/metabolismo , Receptores Acoplados a Proteínas-G/agonistas , Receptores Acoplados a Proteínas-G/metabolismo , Animais , Aminas Biogênicas/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
2.
ACS Chem Neurosci ; 10(10): 4414-4429, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31573179

RESUMO

In the present study, screening of a library of 49,087 compounds at the excitatory amino acid transporter subtype 3 (EAAT3) led to the identification of 2-(furan-2-yl)-8-methyl-N-(o-tolyl)imidazo[1,2-a]pyridin-3-amine (3a) which showed a >20-fold preference for inhibition of EAAT3 (IC50 = 13 µM) over EAAT1,2,4 (EAAT1: IC50 ∼ 250 µM; EAAT2,4: IC50 > 250 µM). It was shown that a small lipophilic substituent (methyl or bromine) at the 7- and/or 8-position was essential for activity. Furthermore, the substitution pattern of the o-tolyl group (compound 5b) and the chemical nature of the substituent in the 2-position (compound 7b) were shown to be essential for the selectivity toward EAAT3 over EAAT1,2. The most prominent analogues to come out of this study are 3a and 3e that display ∼35-fold selectivity for EAAT3 (IC50 = 7.2 µM) over EAAT1,2,4 (IC50 ∼ 250 µM).


Assuntos
Transportador 3 de Aminoácido Excitatório/antagonistas & inibidores , Piridinas/química , Piridinas/farmacologia , Aminas Biogênicas/química , Aminas Biogênicas/farmacologia , Cromatografia em Camada Delgada/métodos , Relação Dose-Resposta a Droga , Transportador 3 de Aminoácido Excitatório/metabolismo , Células HEK293 , Humanos , Relação Estrutura-Atividade
3.
Neurotoxicology ; 69: 278-287, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30075218

RESUMO

Methylmercury (MeHg) is an environmental toxicant with detrimental effects on the developing brain and adult nervous system. The main mechanisms identified include oxidative stress, changes in intracellular calcium, mitochondrial changes, inhibition of glutamate uptake, of protein synthesis and disruption of microtubules. However, little is known about mechanisms of protection against MeHg neurotoxicity. We found that resveratrol (10 µM) and ascorbic acid (200 µM) protected MeHg-induced cell death in primary cultures of cortical neurons. In this work, we aimed at finding additional targets that may be related to MeHg mode of action in cell toxicity with special emphasis in cell protection. We wonder whether neurotransmitters may affect the MeHg effects on neuronal death. Our findings show that neurons exposed to low MeHg concentrations exhibit less mortality if co-exposed to 10 µM dopamine (DA). However, DA metabolites, HVA (homovanillic acid) and DOPAC (3,4-dihydroxyphenylacetic acid) are not responsible for such protection. Furthermore, both DA D1 and D2 receptors agonists showed a protective effect against MeHg toxicity. It is striking though that DA receptor antagonists SKF83566 (10 µM) and haloperidol (10 µM) did not inhibit DA protection against MeHg. In addition, the protective effect of 10 µM DA against MeHg-induced toxicity was not affected by additional organochlorine pollutants exposure. Our results also demonstrate that cells exposed to MeHg in presence of 100 µM acetylcholine (ACh), show an increase in cell mortality at the "threshold value" of 100 nM MeHg. Finally, norepinephrine (10 µM) and serotonin (20 µM) also had an effect on cell protection. Altogether, we propose to further investigate the additional mechanisms that may be playing an important role in MeHg-induced cytotoxicity.


Assuntos
Antioxidantes/farmacologia , Córtex Cerebral/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Neurônios/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Aminas Biogênicas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Citotoxinas/toxicidade , Relação Dose-Resposta a Droga , Feminino , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Neuroproteção/fisiologia , Neurotransmissores/farmacologia , Estresse Oxidativo/fisiologia , Gravidez
4.
J Exp Biol ; 221(Pt 9)2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-29559549

RESUMO

For more than a century, visual learning and memory have been studied in the honeybee Apis mellifera using operant appetitive conditioning. Although honeybees show impressive visual learning capacities in this well-established protocol, operant training of free-flying animals cannot be combined with invasive protocols for studying the neurobiological basis of visual learning. In view of this, different attempts have been made to develop new classical conditioning protocols for studying visual learning in harnessed honeybees, though learning performance remains considerably poorer than that for free-flying animals. Here, we investigated the ability of honeybees to use visual information acquired during classical conditioning in a new operant context. We performed differential visual conditioning of the proboscis extension reflex (PER) followed by visual orientation tests in a Y-maze. Classical conditioning and Y-maze retention tests were performed using the same pair of perceptually isoluminant chromatic stimuli, to avoid the influence of phototaxis during free-flying orientation. Visual discrimination transfer was clearly observed, with pre-trained honeybees significantly orienting their flights towards the former positive conditioned stimulus (CS+), thus showing that visual memories acquired by honeybees are resistant to context changes between conditioning and the retention test. We combined this visual discrimination approach with selective pharmacological injections to evaluate the effect of dopamine and octopamine in appetitive visual learning. Both octopaminergic and dopaminergic antagonists impaired visual discrimination performance, suggesting that both these biogenic amines modulate appetitive visual learning in honeybees. Our study brings new insight into cognitive and neurobiological mechanisms underlying visual learning in honeybees.


Assuntos
Abelhas/efeitos dos fármacos , Aminas Biogênicas/farmacologia , Dopamina/farmacologia , Octopamina/farmacologia , Percepção Visual , Animais , Abelhas/fisiologia , Aminas Biogênicas/administração & dosagem , Condicionamento Operante , Aprendizagem por Discriminação , Dopamina/administração & dosagem , Memória , Octopamina/administração & dosagem
5.
Crit Rev Food Sci Nutr ; 58(10): 1660-1670, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28128651

RESUMO

Foodborne pathogens (FBP) represent an important threat to the consumers' health as they are able to cause different foodborne diseases. In order to eliminate the potential risk of those pathogens, lactic acid bacteria (LAB) have received a great attention in the food biotechnology sector since they play an essential function to prevent bacterial growth and reduce the biogenic amines (BAs) formation. The foodborne illnesses (diarrhea, vomiting, and abdominal pain, etc.) caused by those microbial pathogens is due to various reasons, one of them is related to the decarboxylation of available amino acids that lead to BAs production. The formation of BAs by pathogens in foods can cause the deterioration of their nutritional and sensory qualities. BAs formation can also have toxicological impacts and lead to different types of intoxications. The growth of FBP and their BAs production should be monitored and prevented to avoid such problems. LAB is capable of improving food safety by preventing foods spoilage and extending their shelf-life. LAB are utilized by the food industries to produce fermented products with their antibacterial effects as bio-preservative agents to extent their storage period and preserve their nutritive and gustative characteristics. Besides their contribution to the flavor for fermented foods, LAB secretes various antimicrobial substances including organic acids, hydrogen peroxide, and bacteriocins. Consequently, in this paper, the impact of LAB on the growth of FBP and their BAs formation in food has been reviewed extensively.


Assuntos
Aminas Biogênicas/metabolismo , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Lactobacillales/fisiologia , Aminas Biogênicas/farmacologia , Inocuidade dos Alimentos , Humanos
6.
Cent Nerv Syst Agents Med Chem ; 16(3): 197-207, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26204967

RESUMO

Indolealkylamines (IAAs) are biogenic amines and derivatives of 5-hydroxytryptamine, acting primarily on serotonin receptors. IAAs are often considered the most thoroughly investigated group of aromatic amines in the amphibian skin. On the contrary, at present the detailed knowledge of these compounds in lower organisms is still limited and the biogenic amine receptors, mediating hormonal and modulatory functions, are largely unknown in primitive invertebrates. However, some active research is currently underway investigating this class of biogenic amines. Notably, during the last three decades several investigations have demonstrated the biological activity of endogenous biogenic amines in cnidarians, which are known to be the lowest beings equipped with an effective, even though rudimentary, nervous system. Toads, especially those from the Bufonidae family, constitute a significant part of the amphibian family and are an identified source of IAAs. To date fourteen IAAs have been identified in the skins of toad species. All are 5-substituted IAA derivatives acting mainly on the central nervous system (CNS), with most exhibiting some degrees of 5-HT2A receptor selectivity. This selective ability presents potential for their use in the development of treatments for various disorders such as schizophrenia, depression, anxiety, obsessive-compulsive disorders and chronic pain conditions. There are indications that some IAAs may also show subclass selectivity through binding to multiple 5-HT receptor subtypes. Thus, there exists an additional promising platform for the development of therapeutics targeting multiple 5-HT receptors. In this review, IAAs occurring naturally in various species of toad skins, which have been identified and isolated since 1944 are summarized and comparisons are made with similar biogenic amines recognized in cnidarians to date. Such comparisons highlight the potential to utilize existing knowledge gathered from vertebrates, such as toads in order to improve the understanding of the activities of such compounds in lower invertebrates.


Assuntos
Anuros , Aminas Biogênicas/isolamento & purificação , Aminas Biogênicas/farmacologia , Sistema Nervoso Central/efeitos dos fármacos , Cnidários , Animais , Aminas Biogênicas/química , Humanos , Indóis/química , Indóis/isolamento & purificação , Indóis/farmacologia , Invertebrados , Pele/química , Vertebrados
7.
Molecules ; 19(11): 18139-51, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-25383752

RESUMO

Rice produces a wide array of phytoalexins in response to pathogen attacks and UV-irradiation. Except for the flavonoid sakuranetin, most phytoalexins identified in rice are diterpenoid compounds. Analysis of phenolic-enriched fractions from UV-treated rice leaves showed that several phenolic compounds in addition to sakuranetin accumulated remarkably in rice leaves. We isolated two compounds from UV-treated rice leaves using silica gel column chromatography and preparative HPLC. The isolated phenolic compounds were identified as phenylamide compounds: N-trans-cinnamoyltryptamine and N-p-coumaroylserotonin. Expression analysis of biosynthetic genes demonstrated that genes for arylamine biosynthesis were upregulated by UV irradiation. This result suggested that phenylamide biosynthetic pathways are activated in rice leaves by UV treatment. To unravel the role of UV-induced phenylamides as phytoalexins, we examined their antimicrobial activity against rice fungal and bacterial pathogens. N-trans-Cinnamoyltryptamine inhibited the growth of rice brown spot fungus (Bipolaris oryzae). In addition to the known antifungal activity to the blast fungus, sakuranetin had antimicrobial activity toward B. oryzae and Rhizoctonia solani (rice sheath blight fungus). UV-induced phenylamides and sakuranetin also had antimicrobial activity against rice bacterial pathogens for grain rot (Burkholderia glumae), blight (Xanthomonas oryzae pv. oryzae) and leaf streak (X. oryzae pv. oryzicola) diseases. These findings suggested that the UV-induced phenylamides in rice are phytoalexins against a diverse array of pathogens.


Assuntos
Anti-Infecciosos , Ascomicetos/crescimento & desenvolvimento , Aminas Biogênicas , Burkholderia/crescimento & desenvolvimento , Folhas de Planta , Rhizoctonia/crescimento & desenvolvimento , Raios Ultravioleta , Xanthomonas/crescimento & desenvolvimento , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Aminas Biogênicas/biossíntese , Aminas Biogênicas/química , Aminas Biogênicas/isolamento & purificação , Aminas Biogênicas/farmacologia , Regulação da Expressão Gênica , Oryza/química , Oryza/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo
8.
PLoS One ; 9(9): e97610, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25229890

RESUMO

BACKGROUND: Animal models should display important characteristics of the human disease. Sheep have been considered particularly useful to study allergic airway responses to common natural antigens causing human asthma. A rationale of this study was to establish a model of ovine precision-cut lung slices (PCLS) for the in vitro measurement of airway responses in newborn and adult animals. We hypothesized that differences in airway reactivity in sheep are present at different ages. METHODS: Lambs were delivered spontaneously at term (147d) and adult sheep lived till 18 months. Viability of PCLS was confirmed by the MTT-test. To study airway provocations cumulative concentration-response curves were performed with different allergic response mediators and biogenic amines. In addition, electric field stimulation, passive sensitization with house dust mite (HDM) and mast cells staining were evaluated. RESULTS: PCLS from sheep were viable for at least three days. PCLS of newborn and adult sheep responded equally strong to methacholine and endothelin-1. The responses to serotonin, leukotriene D4 and U46619 differed with age. No airway contraction was evoked by histamine, except after cimetidine pretreatment. In response to EFS, airways in PCLS from adult and newborn sheep strongly contracted and these contractions were atropine sensitive. Passive sensitization with HDM evoked a weak early allergic response in PCLS from adult and newborn sheep, which notably was prolonged in airways from adult sheep. Only few mast cells were found in the lungs of non-sensitized sheep at both ages. CONCLUSION: PCLS from sheep lungs represent a useful tool to study pharmacological airway responses for at least three days. Sheep seem well suited to study mechanisms of cholinergic airway contraction. The notable differences between newborn and adult sheep demonstrate the importance of age in such studies.


Assuntos
Envelhecimento/imunologia , Pulmão/citologia , Pulmão/fisiologia , Ovinos , Alérgenos/farmacologia , Animais , Animais Recém-Nascidos , Aminas Biogênicas/farmacologia , Broncoconstrição/efeitos dos fármacos , Cimetidina/farmacologia , Histamina/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Sobrevivência de Tecidos
9.
J Labelled Comp Radiopharm ; 57(2): 86-91, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24327460

RESUMO

The Maillard reaction of sugars and amines resulting in the formation of glycosylamines and Amadori products is of biological significance, for drug delivery, role in central nervous system, and other potential applications. We have examined the interaction of (18) F-fluorodeoxyglucose ((18) F-FDG) with biological amines to study the formation of (18) F-fluorodeoxyglycosylamines ((18) F-FDGly). Respective amines N-allyl-2-aminomethylpyrrolidine (NAP) and 2-(4'-aminophenyl)-6-hydroxybenzothiazole (PIB precursor) were mixed with FDG to provide glycosylamines, FDGNAP and FDGBTA. Radiosynthesis using (18) F-FDG (2-5 mCi) was carried out to provide (18) F-FDGNAP and (18) F-FDGBTA. Binding of FDGBTA and (18) F-FDGBTA was evaluated in human brain sections of Alzheimer's disease (AD) patients and control subjects using autoradiography. Both FDGNAP and FDGBTA were isolated as stable products. Kinetics of (18) F-FDGNAP reaction indicated a significant product at 4 h (63% radiochemical yield). (18) F-FDGBTA was prepared in 57% yield. Preliminary studies of FDGBTA showed displacement of (3) H-PIB (reduced by 80%), and (18) F-FDGBTA indicated selective binding to Aß-amyloid plaques present in postmortem AD human brain, with a gray matter ratio of 3 between the AD patients and control subjects. We have demonstrated that (18) F-FDG couples with amines under mild conditions to form (18) F-FDGly in a manner similar to click chemistry. Although these amine derivatives are stable in vitro, stability in vivo and selective binding is under investigation.


Assuntos
Benzotiazóis/química , Aminas Biogênicas/síntese química , Fluordesoxiglucose F18/química , Reação de Maillard , Pirrolidinas/química , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/metabolismo , Aminas Biogênicas/farmacologia , Estudos de Casos e Controles , Humanos , Ligação Proteica , Cintilografia
10.
PLoS One ; 8(9): e74489, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24058575

RESUMO

Using pairings of male crayfish Procambarus clarkii with a 3-7% difference in size, we confirmed that physically larger crayfish were more likely to win encounters (winning probability of over 80%). Despite a physical disadvantage, small winners of the first pairings were more likely to win their subsequent conflicts with larger naive animals (winning probability was about 70%). By contrast, the losers of the first pairings rarely won their subsequent conflicts with smaller naive animals (winning probability of 6%). These winner and loser effects were mimicked by injection of serotonin and octopamine. Serotonin-injected naive small crayfish were more likely to win in pairings with untreated larger naive crayfish (winning probability of over 60%), while octopamine-injected naive large animals were beaten by untreated smaller naive animals (winning probability of 20%). Furthermore, the winner effects of dominant crayfish were cancelled by the injection of mianserin, an antagonist of serotonin receptors and were reinforced by the injection of fluoxetin, serotonin reuptake inhibitor, just after the establishment of social order of the first pairings. Injection of octopamine channel blockers, phentolamine and epinastine, by contrast, cancelled the loser effects. These results strongly suggested that serotonin and octopamine were responsible for winner and loser effects, respectively.


Assuntos
Comportamento Agonístico/efeitos dos fármacos , Astacoidea/efeitos dos fármacos , Astacoidea/fisiologia , Aminas Biogênicas/farmacologia , Predomínio Social , Animais , Astacoidea/anatomia & histologia , Comportamento Animal/efeitos dos fármacos , Aminas Biogênicas/administração & dosagem , Tamanho Corporal , Injeções , Masculino , Mianserina/farmacologia , Octopamina/administração & dosagem , Octopamina/farmacologia , Fentolamina/administração & dosagem , Fentolamina/farmacologia , Serotonina/administração & dosagem , Serotonina/farmacologia
11.
Zh Evol Biokhim Fiziol ; 49(2): 111-7, 2013.
Artigo em Russo | MEDLINE | ID: mdl-23789396

RESUMO

In smooth muscles of mollusc Anodonta cygnea, hormones produce regulatory effects on the adenylyl cyclase (AC) signaling system via receptors of the serpentine (biogenic amine, isoproterenol, glucagon) and of tyrosine kinase (insulin) types. Intracellular mechanisms of their action are interconnected. Use of hormones, their antagonists, and pertussis toxin at the combined action of insulin and biogenic amines or of glucagon on the AC activity allows revealing possible intersection points in mechanisms of their action. The combined effect of insulin and serotonin or of glucagon leads to a decrease of stimulation of AC by these hormones, whereas at action of insulin and isoproterenol the AC-stimulatory effect of insulin is blocked, while the AC-inhibitory effect of isoproterenol is preserved both in the presence and in the absence of the non-hydrolyzed GTP analog - guanylylimidodiphosphate (GppNHp). Specific blocking of the AC-stimulatory serotonin effect by cyproheptadine - an antagonist of serotonin receptors - did not affect stimulation of AC by insulin. Beta-adrenoblockers (propranolol and alprenolol) interfered with inhibition of the AC activity by isoproterenol, but did not change the AC stimulation by insulin. Pertussis toxin blocked the AC-inhibitory effect of isoproterenol and attenuated the AC-stimulatory effect of insulin. Thus, in muscles of the mollusc Anodonta cygnea there have been revealed negative interrelations between the AC system, which are realized at the combined effect of insulin and serotonin or of glucagon, probably at the level of receptor of the serpentine type (serotonin, glucagon), while at action of insulin and isoproterenol - at the level of interaction of G1 protein and AC.


Assuntos
Adenilil Ciclases/metabolismo , Anodonta/efeitos dos fármacos , Aminas Biogênicas/farmacologia , Glucagon/farmacologia , Insulina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Inibidores de Adenilil Ciclases , Antagonistas Adrenérgicos beta/farmacologia , Animais , Anodonta/enzimologia , Anodonta/fisiologia , Aminas Biogênicas/administração & dosagem , Aminas Biogênicas/fisiologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Interações Medicamentosas , Glucagon/administração & dosagem , Glucagon/fisiologia , Técnicas In Vitro , Insulina/administração & dosagem , Insulina/fisiologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/enzimologia , Músculo Liso/fisiologia , Transdução de Sinais/fisiologia
12.
J Leukoc Biol ; 93(3): 387-94, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23315425

RESUMO

Certain biogenic amines, such as 2-PEA, TYR, or T1AM, modulate blood pressure, cardiac function, brain monoaminergic systems, and olfaction-guided behavior by specifically interacting with members of a group of rhodopsin-like receptors, TAAR. A receptor that is absent from olfactory epithelia but had long been identified in the brain and a variety of peripheral tissues, TAAR1 has been found recently in blood B cells, suggesting a functional role of TAAR1 in these cells. With the present study, we have set out to clarify the expression and functional roles of TAAR in different isolated human blood leukocyte types. Here, we report the functional expression of TAAR1 and its closest relative TAAR2 in blood PMN and T and B cells. Both receptors are coexpressed in a subpopulation of PMN, where they are necessary for the chemosensory migration toward the TAAR1 ligands 2-PEA, TYR, and T1AM, with EC50 values of 0.43 ± 0.05 nM, 0.52 ± 0.05 nM, and 0.25 ± 0.04 nM, respectively. The same amines, with similar potencies, triggered cytokine or Ig secretion, in purified blood T or B cells, respectively. Notably, 2-PEA regulated mRNA expression of 28 T cell function-related genes, above all of the CCL5. In siRNA-guided experiments, TAAR1 and TAAR2 proved to be necessary for amine-induced blood leukocyte functions. In summary, our results demonstrate that biogenic amines potently regulate blood cell functions via TAAR1 and TAAR2 and open the perspective of their specific pharmacological modulation.


Assuntos
Aminas Biogênicas/farmacologia , Leucócitos Mononucleares/imunologia , Receptores Acoplados a Proteínas-G/imunologia , Anticorpos/imunologia , Aminas Biogênicas/imunologia , Quimiocina CCL5/imunologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Leucócitos Mononucleares/citologia , Masculino
13.
J Neurochem ; 125(1): 37-48, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23356740

RESUMO

In invertebrates, the phenolamines, tyramine and octopamine, mediate many functional roles usually associated with the catecholamines, noradrenaline and adrenaline, in vertebrates. The α- and ß-adrenergic classes of insect octopamine receptor are better activated by octopamine than tyramine. Similarly, the Tyramine 1 subgroup of receptors (or Octopamine/Tyramine receptors) are better activated by tyramine than octopamine. However, recently, a new Tyramine 2 subgroup of receptors was identified, which appears to be activated highly preferentially by tyramine. We examined immunocytochemically the ability of CG7431, the founding member of this subgroup from Drosophila melanogaster, to be internalized in transfected Chinese hamster ovary (CHO) cells by different agonists. It was only internalized after activation by tyramine. Conversely, the structurally related receptor, CG16766, was internalized by a number of biogenic amines, including octopamine, dopamine, noradrenaline, adrenaline, which also were able to elevate cyclic AMP levels. Studies with synthetic agonists and antagonists confirm that CG16766 has a different pharmacological profile to that of CG7431. Species orthologues of CG16766 were only found in Drosophila species, whereas orthologues of CG7431 could be identified in the genomes of a number of insect species. We propose that CG16766 represents a new group of tyramine receptors, which we have designated the Tyramine 3 receptors.


Assuntos
Proteínas de Drosophila/metabolismo , Receptores de Amina Biogênica/metabolismo , Animais , Aminas Biogênicas/farmacologia , Células CHO , Cálcio/metabolismo , Cricetinae , Cricetulus , AMP Cíclico/metabolismo , Proteínas de Drosophila/agonistas , Proteínas de Drosophila/antagonistas & inibidores , Drosophila melanogaster , Espaço Intracelular/metabolismo , Filogenia , Receptores de Amina Biogênica/agonistas , Receptores de Amina Biogênica/antagonistas & inibidores , Sistemas do Segundo Mensageiro , Especificidade da Espécie , Tiramina/farmacologia
14.
Endocrine ; 42(1): 118-24, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22371119

RESUMO

Estrogen receptors (ERα and ERß) mediate the neuroprotection of estrogens against MPTP-induced striatal dopamine (DA) depletion. Pain is an important and distressing symptom in Parkinson's disease (PD). Voltage-gated sodium channels in sensory neurons are involved in the development of neuropathic pain. In this study, MPTP caused changes in nociception and alterations of gene expression of voltage-gated sodium channels in dorsal root ganglion (DRG) neurons in ER knockout (ERKO) mice were investigated. We found that administration of MPTP (11 mg/kg) to WT mice led to an extensive depletion of DA and its two metabolites, αERKO mice were observed to be more susceptible to MPTP toxicity than ßERKO or WT mice. In addition, we found that the mRNA levels of TTX-S and TTX-R sodium channel subtypes were differentially affected in MPTP-treated WT animals. The MPTP-induced up-regulation of Nav1.1 and Nav1.9, down-regulation of Nav1.6 in DRG neurons may be through ERß, up-regulation of Nav1.7 and down-regulation of Nav1.8 are dependent on both ERα and ERß. Therefore, the MPTP-induced alterations of gene expression of sodium channels in DRG neurons could be an important mechanism to affect excitability and nociceptive thresholds, and the ERs appear to play a role in nociception in PD.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Gânglios Espinais/metabolismo , Neurônios/efeitos dos fármacos , Receptores Estrogênicos/genética , Canais de Sódio Disparados por Voltagem/genética , Animais , Aminas Biogênicas/farmacologia , Dopaminérgicos/farmacologia , Regulação da Expressão Gênica/genética , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/genética , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Medição da Dor , Receptores Estrogênicos/metabolismo , Regulação para Cima/efeitos dos fármacos , Canais de Sódio Disparados por Voltagem/metabolismo
15.
Naturwissenschaften ; 99(2): 123-31, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22205342

RESUMO

In honeybees, workers under queenless condition compete for reproduction and establish reproductive dominance hierarchy. Ovary activation is generally accompanied by the expression of queen-like pheromones. Biogenic amines (BAs), in particular dopamine, are believed to be involved in this process by regulating ovarian development. However, the role of BAs in establishing reproductive dominance or their effect on queen-like pheromone production was not investigated. Here, we explored the effect of octopamine (OA) and tyramine (TA) oral treatments on the propensity of treated bees to become reproductively dominant and produce queen-like pheromones in Dufour's and mandibular glands. One bee in a pair was treated with either OA or TA while the other was fed sugar solution. TA was found to enhance ovary development and the production of esters in the Dufour's gland and 9HDA (queen component) in the mandibular glands, thus facilitating worker reproductive dominance. OA, on the other hand, did not enhance ovarian development or ester production, but increased the production of 10HDA (worker major component) in the mandibular glands of their sugar-paired mates. OA is known to induce foraging behavior by workers, while increased production of 10HDA characterizes nursing workers. Therefore, we suggest that TA induces reproductive division of labor, while OA treatment results in caste differentiation of workers to foragers and nurses.


Assuntos
Abelhas/fisiologia , Octopamina/metabolismo , Tiramina/metabolismo , Animais , Abelhas/efeitos dos fármacos , Abelhas/metabolismo , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Aminas Biogênicas/farmacologia , Química Encefálica/efeitos dos fármacos , Feminino , Feromônios/metabolismo , Reprodução/efeitos dos fármacos , Reprodução/fisiologia , Predomínio Social
16.
J Exp Biol ; 214(Pt 19): 3286-93, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21900476

RESUMO

The glowworm Arachnocampa flava is a carnivorous fly larva (Diptera) that uses light to attract prey into its web. The light organ is derived from cells of the Malpighian tubules, representing a bioluminescence system that is unique to the genus. Bioluminescence is modulated through the night although light levels change quite slowly compared with the flashing of the better-known fireflies (Coleoptera). The existing model for the neural regulation of bioluminescence in Arachnocampa, based on use of anaesthetics and ligations, is that bioluminescence is actively repressed during the non-glowing phase and the repression is partially released during the bioluminescence phase. The effect of the anaesthetic, carbon dioxide, on the isolated light organ from the present study indicates that the repression is at least partially mediated at the light organ itself rather than less directly through the central nervous system. Blocking of neural signals from the central nervous system through ligation leads to uncontrolled release of bioluminescence but light is emitted at relatively low levels compared with under anaesthesia. Candidate biogenic amines were introduced by several methods: feeding prey items injected with test solution, injecting the whole larva, injecting a ligated section containing the light organ or bathing the isolated light organ in test solution. Using these methods, dopamine, serotonin and tyramine do not affect bioluminescence output. Exposure to elevated levels of octopamine via feeding, injection or bathing of the isolated light organ indicates that it is involved in the regulation of repression. Administration of the octopamine antagonists phentolamine or mianserin results in very high bioluminescence output levels, similar to the effect of anaesthetics, but only mianserin acts directly on the light organ.


Assuntos
Aminas Biogênicas/farmacologia , Dípteros/metabolismo , Proteínas Luminescentes/metabolismo , Túbulos de Malpighi/metabolismo , Análise de Variância , Animais , Aminas Biogênicas/metabolismo , Dióxido de Carbono , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Larva/metabolismo , Mianserina/farmacologia , Octopamina/antagonistas & inibidores , Octopamina/metabolismo , Fentolamina/farmacologia , Queensland
17.
Naturwissenschaften ; 98(11): 989-93, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21947195

RESUMO

Virgin female cabbage butterflies, Pieris rapae crucivora, accept and mate with courting males, whereas mated females reject them and assume the "mate refusal posture". This study tested whether the biogenic amines, serotonin (5HT), dopamine (DA), and octopamine (OA), were responsible for this change in behavior. The results showed that 2-3-day-old virgin females fed with 5HT rejected courting males significantly more frequently compared with controls fed on sucrose. In contrast, the proportions of courting males rejected by virgin females fed with either DA or OA did not differ from sucrose-fed controls. Oral application of each amine resulted in significantly increased levels of the amine applied (or its metabolite) in the brain. The results strongly suggest that 5HT or a 5HT metabolite may be responsible for the post-mating change in behavioral response of 2-3-day-old virgin females to courting males. Similar effects of 5HT treatment were observed in 6-8-day-old virgin females, but in this case the results were only marginally different from the controls, suggesting that the effect may decline with increasing female age.


Assuntos
Aminas Biogênicas/farmacologia , Borboletas/efeitos dos fármacos , Serotonina/farmacologia , Animais , Feminino , Hormônios de Inseto/farmacologia , Masculino , Comportamento Sexual Animal/efeitos dos fármacos
18.
Handb Exp Pharmacol ; (200): 201-34, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20859797

RESUMO

The effects of theobromine in man are underresearched, possibly owing to the assumption that it is behaviourally inert. Toxicology research in animals may appear to provide alarming results, but these cannot be extrapolated to humans for a number of reasons. Domestic animals and animals used for racing competitions need to be guarded from chocolate and cocoa-containing foods, including foods containing cocoa husks. Research ought to include caffeine as a comparative agent, and underlying mechanisms need to be further explored. Of all constituents proposed to play a role in our liking for chocolate, caffeine is the most convincing, though a role for theobromine cannot be ruled out. Most other substances are unlikely to exude a psychopharmacological effect owing to extremely low concentrations or the inability to reach the blood-brain barrier, whilst chocolate craving and addiction need to be explained by means of a culturally determined ambivalence towards chocolate.


Assuntos
Cacau , Teobromina/farmacologia , Animais , Aminas Biogênicas/farmacologia , Cafeína/farmacologia , Doping nos Esportes , Humanos , Teobromina/metabolismo , Teobromina/toxicidade
19.
Artigo em Inglês | MEDLINE | ID: mdl-20836008

RESUMO

The scents of mammals are complex blends of natural products that reveal a wealth of individual information. Many mammals can decipher these scent codes to discern the gender, age, endocrine status, social status, and genotype of conspecifics using dedicated sensory receptors in their olfactory system. Among these social odors are pheromones, chemicals that trigger innate behaviors and physiological responses. Here, we review classes of mammal-derived natural products that influence behavior through activation of the olfactory system.


Assuntos
Mamíferos , Condutos Olfatórios/fisiologia , Percepção Olfatória/fisiologia , Olfato/fisiologia , Androsterona/metabolismo , Androsterona/farmacologia , Androsterona/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Aminas Biogênicas/metabolismo , Aminas Biogênicas/farmacologia , Aminas Biogênicas/fisiologia , Humanos , Mamíferos/genética , Mamíferos/metabolismo , Mamíferos/fisiologia , Modelos Biológicos , Odorantes , Condutos Olfatórios/metabolismo , Percepção Olfatória/genética , Feromônios/farmacologia , Feromônios/fisiologia , Olfato/genética
20.
Aviakosm Ekolog Med ; 44(2): 53-5, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20799661

RESUMO

Microelectrodes and micro-iontophoresis of physiologically active substances in experiments with cats immobilized by muscle relaxants made it apparent that different classical neuromediators (acetylcholine, norepinephrine, GABA and others) and regulatory peptides (enkephalins, thyrotropin-releasing hormone, vasoactive intestinal peptide (VIP), somatostatin (SS) and others) are capable to influence directly 68 to 100% of neurons in vestibular zone-I of the cerebral cortex. In the presence of L-glutamate, the inhibiting effect of enkephalins, VIP and SS on the neurons impulse activity was essentially unaltered. Also it was shown that enkephalins, VIP and SS are potent to augment the inhibiting effect of GABA and glycine. Therefore, these substances may have the neuromediator and/or neuromodulator role in this cortical zone.


Assuntos
Aminoácidos/farmacologia , Aminas Biogênicas/farmacologia , Córtex Cerebral/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neuropeptídeos/farmacologia , Hormônios Peptídicos/farmacologia , Ácido gama-Aminobutírico/farmacologia , Animais , Gatos , Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Neurônios/fisiologia
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