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Sample records for 5ht2a tph1 tph2

  1. Association between Serotonin-Related Polymorphisms in 5HT2A, TPH1, TPH2 Genes and Bipolar Disorder in Korean Population

    OpenAIRE

    Choi, Kwang-Yeon; Yoon, Ho-Kyoung; Kim, Yong-Ku

    2010-01-01

    Objective The aim of the present study was to examine the association between serotonin-related gene polymorphisms and bipolar disorder in the Korean population. In addition, we sought to explore the relationship between the clinical characteristics of bipolar patients and serotonin-related gene polymorphisms. Methods Inpatients with bipolar disorder (n=103) and control subjects (n=86) were genotyped for 5HT2A 1438A/G, tryptophan hydroxylase 1 (TPH1) 218 A/C, and TPH2 703G/T. We divided patie...

  2. Association between 5-HT2A, TPH1 and GNB3 genotypes and response to typical neuroleptics: a serotonergic approach

    Directory of Open Access Journals (Sweden)

    Kampman Olli

    2007-05-01

    Full Text Available Abstract Background Schizophrenia is a common psychiatric disease affecting about 1% of population. One major problem in the treatment is finding the right the drug for the right patients. However, pharmacogenetic results in psychiatry can seldom be replicated. Methods We selected three candidate genes associated with serotonergic neurotransmission for the study: serotonin 2A (5-HT2A receptor gene, tryptophan hydroxylase 1 (TPH1 gene, and G-protein beta-3 subunit (GNB3 gene. We recruited 94 schizophrenia patients representing extremes in treatment response to typical neuroleptics: 43 were good responders and 51 were poor responders. The control group consisted of 392 healthy blood donors. Results We do, in part, replicate the association between 5-HT2A T102C polymorphism and response to typical neuroleptics. In female patients, C/C genotype was significantly more common in non-responders than in responders [OR = 6.04 (95% Cl 1.67–21.93, p = 0.005] or in the control population [OR = 4.16 (95% CI 1.46–11.84, p = 0.005]. TPH1 A779C C/A genotype was inversely associated with good treatment response when compared with non-responders [OR = 0.59 (95% Cl 0.36–0.98, p = 0.030] or with the controls [OR = 0.44 (95% CI 0.23–0.86, p = 0.016], and GNB3 C825T C/T genotype showed a trend-like positive association among the male patients with a good response compared with non-responders [OR = 3.48 (95% Cl 0.92–13.25, p = 0.061], and a clearer association when compared with the controls [OR = 4.95 (95% CI 1.56–15.70, p = 0.004]. Conclusion More findings on the consequences of functional polymorphisms for the role of serotonin in the development of brain and serotonergic neurotransmission are needed before more detailed hypotheses regarding susceptibility and outcome in schizophrenia can be formulated. The present results may highlight some of the biological mechanisms in different courses of schizophrenia between men and women.

  3. Cerebral 5-HT2A receptor binding, but not mGluR2, is increased in tryptophan hydroxylase 2 decrease-of-function mice

    DEFF Research Database (Denmark)

    Jørgensen, Christinna Vangsgaard; Jacobsen, Jacob P; Caron, Marc G;

    2013-01-01

    Transgenic mice with a knock-in (KI) of a tryptophan hydroxylase 2 (Tph2) R439H mutation, analogous to the Tph2 R441H single-nucleotide polymorphism originally identified in a late life depression cohort, have markedly reduced levels of 5-hydroxytryptamine (5-HT). These Tph2KI mice are therefore...... interesting as a putative translational model of low endogenous 5-HT function that allows for assessment of adaptive changes in different anatomical regions. Here, we determined 5-HT2A receptor binding in several brain regions using in vitro receptor autoradiography and two different radioligands. When using....... These data show that in distinct anatomical regions, 5-HT2A receptor binding sites are up-regulated in 5-HT deficient mice, and this increase is not associated with changes in mGluR2 binding....

  4. BDNF downregulates 5-HT(2A) receptor protein levels in hippocampal cultures

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    Trajkovska, V; Santini, M A; Marcussen, Anders Bue;

    2009-01-01

    Both brain-derived neurotrophic factor (BDNF) and the serotonin receptor 2A (5-HT(2A)) have been related to depression pathology. Specific 5-HT(2A) receptor changes seen in BDNF conditional mutant mice suggest that BDNF regulates the 5-HT(2A) receptor level. Here we show a direct effect of BDNF...... on 5-HT(2A) receptor protein levels in primary hippocampal neuronal and mature hippocampal organotypic cultures exposed to different BDNF concentrations for either 1, 3, 5 or 7 days. In vivo effects of BDNF on hippocampal 5-HT(2A) receptor levels were further corroborated in (BDNF +/-) mice...... with reduced BDNF levels. In primary neuronal cultures, 7 days exposure to 25 and 50ng/mL BDNF resulted in downregulation of 5-HT(2A), but not of 5-HT(1A), receptor protein levels. The BDNF-associated downregulation of 5-HT(2A) receptor levels was also observed in mature hippocampal organotypic cultures...

  5. Discovery of a Novel 5-HT2A Inhibitor by Pharmacophore-based Virtual Screening

    Institute of Scientific and Technical Information of China (English)

    XIONG Zi-jun; DU Peng; LI Bian; XU Li-li; ZHEN Xue-chu; FU Wei

    2011-01-01

    The serotonin 2A(5-HT2A) receptor has been implicated in several neurological conditions and potent 5-HT2A antagonists have therapeutic effects in the treatment of schizophrenia and depression.In this study,a potent novel 5-HT2A inhibitor 05245768 with a Ki value of (593.89±34.10) nmol/L was discovered by integrating a set of computational approaches and experiments(protein structure prediction,pharmacophore-based virtual screening,automated molecular docking and pharmacological bioassay).The 5-HT2A receptor showed a negatively charged binding pocket.The binding mode of compound 05245768 with 5-HT2A was obtained by GOLD docking procedure,which revealed the conserved interaction between protonated nitrogen in compound 05245768 and carboxylate group of D3.32 at the active site of 5-HT2A.

  6. Reduced 5-HT2A receptor binding in patients with mild cognitive impairment

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    Hasselbalch, S G; Madsen, K; Svarer, C;

    2008-01-01

    Previous studies of patients with Alzheimer's disease (AD) have described reduced brain serotonin 2A (5-HT(2A)) receptor density. It is unclear whether this abnormality sets in early in the course of the disease and whether it is related to early cognitive and neuropsychiatric symptoms. We assessed...... cerebral 5-HT(2A) receptor binding in patients with mild cognitive impairment (MCI) and related 5-HT(2A) receptor binding to clinical symptoms. Sixteen patients with MCI of the amnestic type (mean age 73, mean MMSE 26.1) and 17 age and sex matched control subjects were studied with MRI and [(18)F......]altanserin PET in a bolus-infusion approach. A significant global reduction of 20-30% in 5-HT(2A) binding (atrophy corrected) was found in most neocortical areas. Reduced 5-HT(2A) binding in the striatum correlated significantly with Neuropsychiatric Inventory depression and anxiety scores. We conclude...

  7. The 5-HT2A receptor binding pattern in the human brain is strongly genetically determined

    DEFF Research Database (Denmark)

    Pinborg, Lars H; Arfan, Haroon; Haugbol, Steven;

    2007-01-01

    variability in cortical 5-HT(2A) receptor binding as measured with [(18)F]altanserin PET imaging. The intraclass correlation coefficients were 0.67 for dizygotic and 0.87 for monozygotic twin pairs. For comparison, the intraclass correlation coefficient was 0.93 in a group of six male healthy subjects...... brain anatomy is largely genetically determined, it is currently unknown to what degree neuromodulatory markers are subjected to genetic and environmental influence. Changes in serotonin 2A (5-HT(2A)) receptors have been reported to occur in various neuropsychiatric disorders and an association between...

  8. Radiosynthesis, evaluation and preclinical studies of a new 5HT2A radioligand

    International Nuclear Information System (INIS)

    123I-5-I-R91150, a radioiodinated analogue of R91150 (a ligand (antagonist) of Janssen Research Foundation), showing high affinity and selectivity for 5HT2A receptors, was developed as a potential in vivo 5HT2A receptor tracer for SPECT. The applied radiochemistry, whereby the radioiodine was substituted on the 5 - position of the benzamide ring, allowed to obtain the tracer with high specific activity and high purity. In vitro and in vivo rat studies revealed that the new tracer bound reversibly with the required high affinity (Kd=0.1 nM) and high selectivity (a factor ranging from 10000 to at least 50 vis a vis other receptors) to 5HT2A receptors. In young normal subjects the major part of the 123I-5-I-R91150 radioactivity in the brain is present in cortical areas. Cortical area to cerebellum activity ratio reaches an equilibrium value of about 1.8 around 90 min. till 4 hours p.i.. This binding was specific and reversible. The cortical activity reflects a distribution in the brain similar to that of the mapping of 5HT2A receptors from post mortem studies. These findings suggested that 123I-5-I-R91150 allows imaging and quantitative estimation with SPECT and could be used for further clinical studies. The radiobromine analogue was synthetised as a potential PET tracer. (author)

  9. Activation of glucocorticoid receptors increases 5-HT2A receptor levels

    DEFF Research Database (Denmark)

    Trajkovska, Viktorija; Kirkegaard, Lisbeth; Krey, Gesa;

    2009-01-01

    of depression is unknown. In mice with altered glucocorticoid receptor (GR) expression we investigated 5-HT2A receptor levels by Western blot and 3H-MDL100907 receptor binding. Serotonin fibre density was analyzed by stereological quantification of serotonin transporter immunopositive fibers. To establish...... in dorsal hippocampus (77 +/- 35%, p

  10. 5-HT2A : a serotonin receptor with a possible role in joint diseases

    OpenAIRE

    Kling, Anders

    2013-01-01

    Background Serotonin (5-HT), an amino acid derivative and neurotransmitter, has for long been studied in relation to inflammation. It is an endogenous ligand for several different types of serotonin receptors. The serotonin receptor 5-HT2A has been reported to have a role in the pathophysiology of arthritis in animal experiment models. However, no studies into this subject have been reported in man. Objective The objectives of this project were firstly, to examine possible associations for th...

  11. Serotonin 5-HT(2A) receptor activation induces 2-arachidonoylglycerol release through a phospholipase c-dependent mechanism.

    Science.gov (United States)

    Parrish, Jason C; Nichols, David E

    2006-11-01

    To date, several studies have demonstrated that phospholipase C-coupled receptors stimulate the production of endocannabinoids, particularly 2-arachidonoylglycerol. There is now evidence that endocannabinoids are involved in phospholipase C-coupled serotonin 5-HT(2A) receptor-mediated behavioral effects in both rats and mice. The main objective of this study was to determine whether activation of the 5-HT(2A) receptor leads to the production and release of the endocannabinoid 2-arachidonoylglycerol. NIH3T3 cells stably expressing the rat 5-HT(2A) receptor were first incubated with [(3)H]-arachidonic acid for 24 h. Following stimulation with 10 mum serotonin, lipids were extracted from the assay medium, separated by thin layer chromatography, and analyzed by liquid scintillation counting. Our results indicate that 5-HT(2A) receptor activation stimulates the formation and release of 2-arachidonoylglycerol. The 5-HT(2A) receptor-dependent release of 2-arachidonoylglycerol was partially dependent on phosphatidylinositol-specific phospholipase C activation. Diacylglycerol produced downstream of 5-HT(2A) receptor-mediated phospholipase D or phosphatidylcholine-specific phospholipase C activation did not appear to contribute to 2-arachidonoylglycerol formation in NIH3T3-5HT(2A) cells. In conclusion, our results support a functional model where neuromodulatory neurotransmitters such as serotonin may act as regulators of endocannabinoid tone at excitatory synapses through the activation of phospholipase C-coupled G-protein coupled receptors. PMID:17010161

  12. Changes in 5-HT2A-mediated behavior and 5-HT2A- and 5-HT1A receptor binding and expression in conditional brain-derived neurotrophic factor knock-out mice

    DEFF Research Database (Denmark)

    Klein, A B; Santini, M A; Aznar, S;

    2010-01-01

    Changes in brain-derived neurotrophic factor (BDNF) expression have been implicated in the etiology of psychiatric disorders. To investigate pathological mechanisms elicited by perturbed BDNF signaling, we examined mutant mice with central depletion of BDNF (BDNF(2L/2LCk-cre)). A severe impairment...... specific for the serotonin 2A receptor (5-HT(2A)R) in prefrontal cortex was described previously in these mice. This is of much interest, as 5-HT(2A)Rs have been linked to neuropsychiatric disorders and anxiety-related behavior. Here we further characterized the serotonin receptor alterations triggered...... by BDNF depletion. 5-HT(2A) ([(3)H]-MDL100907) and 5-HT(1A) ([(3)H]-WAY100635) receptor autoradiography revealed site-specific alterations in BDNF mutant mice. They exhibited lower 5-HT(2A) receptor binding in frontal cortex but increased binding in hippocampus. Additionally, 5-HT(1A) receptor binding...

  13. Cortical and subcortical 5-HT2A receptor binding in neuroleptic-naive first-episode schizophrenic patients

    DEFF Research Database (Denmark)

    Erritzoe, David; Rasmussen, Hans; Kristiansen, Klaus Nyegaard;

    2008-01-01

    .5+/-5.7 years) and gender underwent a 40 min positron emission tomography (PET) study using the 5-HT(2A) antagonist, [(18)F]altanserin, as a radioligand. PET images were co-registered to 3 T magnetic resonance images (MRIs) for each individual subject, and ROIs were applied automatically onto the individual...... in the caudate nucleus was detected in the group of schizophrenic patients (0.7+/-0.1) when compared to the healthy controls (0.5+/-0.3) (p=0.02). Our results confirm other in vivo findings of no difference in cortical 5-HT(2A) receptor binding between first-episode antipsychotic-naive schizophrenic patients...... and age- and gender-matched healthy control subjects. However, a preliminary finding of increased 5-HT(2A) binding in the caudate nucleus requires further investigation to explore the relation of subcortical and cortical 5-HT(2A) receptor binding....

  14. Htr2a gene and 5-HT2A receptor expression in the cerebral cortex studied using genetically modified mice

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    Rodrigo Andrade

    2010-08-01

    Full Text Available Serotonin receptors of the 5-HT2A subtype are robustly expressed in the cerebral cortex where they have been implicated in the pathophysiology and therapeutics of mental disorders and the actions of hallucinogens. Much less is known, however, about the specific cell types expressing 5-HT2A receptors in cortex. In the current study we use immunohistochemical and electrophysiological approaches in genetically modified mice to address the expression of the Htr2a gene and 5-HT2A receptors in cortex. We first use an EGFP expressing BAC transgenic mice and identify three main Htr2A gene expressing neuronal populations in cortex. The largest of these cell populations corresponds to layer V pyramidal cells of the anterior cortex, followed by GABAergic interneurons of the middle layers, and nonpyramidal cells of the subplate/Layer VIb. We then use 5-HT2A receptor knockout mice to identify an antibody capable of localizing 5-HT2A receptors in brain and use it to map these receptors. We find strong laminar expression of 5-HT2A receptors in cortex, especially along a diffuse band overlaying layer Va. This band exhibits a strong anteroposterior gradient that closely matches the localization of Htr2A expressing pyramidal cells of layer V. Finally we use electrophysiological and immunohistochemical approaches to show that most, but not all, GABAergic interneurons of the middle layers are parvalbumin expressing Fast-spiking interneurons and that these cells are depolarized and excited by serotonin, most likely through the activation of 5-HT2A receptors. These results clarify and extend our understanding of the cellular distribution of 5-HT2A receptors in the cerebral cortex.

  15. 5HT2A and 5HT2B Receptors Contribute to Serotonin-Induced Vascular Dysfunction in Diabetes

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    Peter M. Nelson

    2012-01-01

    Full Text Available Although 5HT2A receptors mediate contractions of normal arteries to serotonin (5HT, in some cardiovascular diseases, other receptor subtypes contribute to the marked increase in serotonin contractions. We hypothesized that enhanced contractions of arteries from diabetics to 5HT are mediated by an increased contribution from multiple 5HT receptor subtypes. We compared responses to selective 5HT receptor agonists and expression of 5HT receptor isoforms (5HT1B, 5HT2A, and 5HT2B in aorta from nondiabetic (ND compared to type 2 diabetic mice (DB, BKS.Cg-Dock7m+/+Leprdb/J. 5HT, 5HT2A (TCB2 and BRL54443, and 5HT2B (norfenfluramine and BW723C86 receptor agonists produced concentration-dependent contractions of ND arteries that were markedly increased in DB arteries. Neither ND nor DB arteries contracted to a 5HT1B receptor agonist. MDL11939, a 5HT2A receptor antagonist, and LY272015, a 5HT2B receptor antagonist, reduced contractions of arteries from DB to 5HT more than ND. Expression of 5HT1B, 5HT2A, and 5HT2B receptor subtypes was similar in ND and DB. Inhibition of rho kinase decreased contractions to 5HT and 5HT2A and 5HT2B receptor agonists in ND and DB. We conclude that in contrast to other cardiovascular diseases, enhanced contraction of arteries from diabetics to 5HT is not due to a change in expression of multiple 5HT receptor subtypes.

  16. Agonist properties of N,N-dimethyltryptamine at serotonin 5-HT2A and 5-HT2C receptors.

    Science.gov (United States)

    Smith, R L; Canton, H; Barrett, R J; Sanders-Bush, E

    1998-11-01

    Extensive behavioral and biochemical evidence suggests an agonist role at the 5-HT2A receptor, and perhaps the 5-HT2C receptor, in the mechanism of action of hallucinogenic drugs. However the published in vitro pharmacological properties of N,N-dimethyltryptamine (DMT), an hallucinogenic tryptamine analog, are not consistent with this hypothesis. We, therefore, undertook an extensive investigation into the properties of DMT at 5-HT2A and 5-HT2C receptors. In fibroblasts transfected with the 5-HT2A receptor or the 5-HT2C receptor, DMT activated the major intracellular signaling pathway (phosphoinositide hydrolysis) to an extent comparable to that produced by serotonin. Because drug efficacy changes with receptor density and cellular microenvironment, we also examined the properties of DMT in native preparations using a behavioral and biochemical approach. Rats were trained to discriminate an antagonist ketanserin from an agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) in a two-lever choice paradigm. Pharmacological studies showed that responding on the DOI and ketanserin lever reflected agonist and antagonist activity at 5-HT2A receptors, and hence, was a suitable model for evaluating the in vivo functional properties of DMT. Like other 5-HT2A receptor agonists, DMT substituted fully for DOI. Intact choroid plexus was used to evaluate the agonist properties at endogenous 5-HT2C receptors; DMT was a partial agonist at 5-HT2C receptors in this native preparation. Thus, we conclude that DMT behaves as an agonist at both 5-HT2A and 5-HT2A receptors. One difference was evident in that the 5-HT2C, but not the 5-HT2A, receptor showed a profound desensitization to DMT over time. This difference is interesting in light of the recent report that the hallucinogenic activity of DMT does not tolerate in humans and suggests the 5-HT2C receptor plays a less prominent role in the action of DMT. PMID:9768567

  17. 5-HT2A Receptor Binding in the Frontal Cortex of Parkinson's Disease Patients and Alpha-Synuclein Overexpressing Mice

    DEFF Research Database (Denmark)

    Rasmussen, Nadja Bredo; Olesen, Mikkel Vestergaard; Brudek, Tomasz;

    2016-01-01

    The 5-HT2A receptor is highly involved in aspects of cognition and executive function and seen to be affected in neurodegenerative diseases like Alzheimer's disease and related to the disease pathology. Even though Parkinson's disease (PD) is primarily a motor disorder, reports of impaired...... executive function are also steadily being associated with this disease. Not much is known about the pathophysiology behind this. The aim of this study was thereby twofold: (1) to investigate 5-HT2A receptor binding levels in Parkinson's brains and (2) to investigate whether PD associated pathology, alpha...

  18. Changes in 5-HT2A-mediated behavior and 5-HT2A- and 5-HT1A receptor binding and expression in conditional brain-derived neurotrophic factor knock-out mice

    DEFF Research Database (Denmark)

    Klein, A B; Santini, M A; Aznar, S;

    2010-01-01

    Changes in brain-derived neurotrophic factor (BDNF) expression have been implicated in the etiology of psychiatric disorders. To investigate pathological mechanisms elicited by perturbed BDNF signaling, we examined mutant mice with central depletion of BDNF (BDNF(2L/2LCk-cre)). A severe impairment...... by BDNF depletion. 5-HT(2A) ([(3)H]-MDL100907) and 5-HT(1A) ([(3)H]-WAY100635) receptor autoradiography revealed site-specific alterations in BDNF mutant mice. They exhibited lower 5-HT(2A) receptor binding in frontal cortex but increased binding in hippocampus. Additionally, 5-HT(1A) receptor binding...... was decreased in hippocampus of BDNF mutants, but unchanged in frontal cortex. Molecular analysis indicated corresponding changes in 5-HT(2A) and 5-HT(1A) mRNA expression but normal 5-HT(2C) content in these brain regions in BDNF(2L/2LCk-cre) mice. We investigated whether the reduction in frontal 5-HT(2A...

  19. Generation of a Tph2 Conditional Knockout Mouse Line for Time- and Tissue-Specific Depletion of Brain Serotonin.

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    Barbara Pelosi

    Full Text Available Serotonin has been gaining increasing attention during the last two decades due to the dual function of this monoamine as key regulator during critical developmental events and as neurotransmitter. Importantly, unbalanced serotonergic levels during critical temporal phases might contribute to the onset of neuropsychiatric disorders, such as schizophrenia and autism. Despite increasing evidences from both animal models and human genetic studies have underpinned the importance of serotonin homeostasis maintenance during central nervous system development and adulthood, the precise role of this molecule in time-specific activities is only beginning to be elucidated. Serotonin synthesis is a 2-step process, the first step of which is mediated by the rate-limiting activity of Tph enzymes, belonging to the family of aromatic amino acid hydroxylases and existing in two isoforms, Tph1 and Tph2, responsible for the production of peripheral and brain serotonin, respectively. In the present study, we generated and validated a conditional knockout mouse line, Tph2flox/flox, in which brain serotonin can be effectively ablated with time specificity. We demonstrated that the Cre-mediated excision of the third exon of Tph2 gene results in the production of a Tph2null allele in which we observed the near-complete loss of brain serotonin, as well as the growth defects and perinatal lethality observed in serotonin conventional knockouts. We also revealed that in mice harbouring the Tph2null allele, but not in wild-types, two distinct Tph2 mRNA isoforms are present, namely Tph2Δ3 and Tph2Δ3Δ4, with the latter showing an in-frame deletion of amino acids 84-178 and coding a protein that could potentially retain non-negligible enzymatic activity. As we could not detect Tph1 expression in the raphe, we made the hypothesis that the Tph2Δ3Δ4 isoform can be at the origin of the residual, sub-threshold amount of serotonin detected in the brain of Tph2null/null mice

  20. Serotonin 5-HT2A receptor gene variants influence antidepressant response to repeated total sleep deprivation in bipolar depression.

    Science.gov (United States)

    Benedetti, Francesco; Barbini, Barbara; Bernasconi, Alessandro; Fulgosi, Mara Cigala; Colombo, Cristina; Dallaspezia, Sara; Gavinelli, Chiara; Marino, Elena; Pirovano, Adele; Radaelli, Daniele; Smeraldi, Enrico

    2008-12-12

    5-HT2A receptor density in prefrontal cortex was associated with depression and suicide. 5-HT2A receptor gene polymorphism rs6313 was associated with 5-HT2A receptor binding potential, with the ability of individuals to use environmental support in order to prevent depression, and with sleep improvement after antidepressant treatment with mirtazapine. Studies on response to antidepressant drugs gave inconsistent results. Here we studied the effect of rs6313 on response to repeated total sleep deprivation (TSD) in 80 bipolar depressed inpatients treated with three consecutive TSD cycles (each one made of 36 h awake followed by a night of undisturbed sleep). All genotype groups showed comparable acute effects of the first TSD, but patients homozygotes for the T variant had better perceived and observed benefits from treatment than carriers of the C allele. These effects became significant after the first recovery night and during the following days, leading to a 36% higher final response rate (Hamilton depression rating<8). The higher density of postsynaptic excitatory 5-HT2A receptors in T/T homozygotes could have led to higher behavioural effects of increased 5-HT neurotransmission due to repeated TSD. Other possible mechanisms involve allostatic/homeostatic adaptation to sleep loss, and a different effect of the allele variants on epigenetic influences. Results confirm the interest for individual gene variants of the serotonin pathway in shaping clinical characteristics of depression and antidepressant response.

  1. 5-Hydroxytryptamine-induced bladder hyperactivity via the 5-HT2A receptor in partial bladder outlet obstruction in rats.

    Science.gov (United States)

    Sakai, Takumi; Kasahara, Ken-ichi; Tomita, Ken-ichi; Ikegaki, Ichiro; Kuriyama, Hiroshi

    2013-04-01

    We investigated the effects of partial bladder outlet obstruction (BOO) on the function and gene expression of 5-hydroxytryptamine (5-HT) receptor subtypes in rat bladder. Isometric contractions of the isolated bladders from sham-operated control and BOO rats were examined. The contractile responses to 5-HT were significantly increased in BOO rat bladder strips, while the responses to KCl, carbachol, or phenylephrine were not different from the control. The 5-HT-induced hypercontraction in BOO rat bladder strips was inhibited by ketanserin, a 5-HT(2A) receptor antagonist. The contractile responses to 5-HT in bladder strips were not affected by urothelium removal from the intact bladder. The gene expression of 5-HT receptor subtypes in the bladders was analyzed by RT-PCR. The mRNA expression of the 5-HT(2A), 5-HT(2B), 5-HT(2C), 5-HT(4), and 5-HT(7) receptors was detected in both the control and BOO rat bladders. Quantitative RT-PCR analysis showed there was a significant increase of 5-HT(2A) receptor mRNA in the BOO rat bladder compared with the control bladder. On the other hand, the gene expression of the 5-HT(4) receptor was not changed in the BOO rat bladder. These results suggest that the increased contractile responses to 5-HT in BOO rat bladder may be partly caused by 5-HT(2A) receptor upregulation in the detrusor smooth muscles. PMID:23344575

  2. Trait aggression and trait impulsivity are not related to frontal cortex 5-HT2A receptor binding in healthy individuals

    DEFF Research Database (Denmark)

    da Cunha-Bang, Sophie; Stenbæk, Dea Siggaard; Holst, Klaus;

    2013-01-01

    age 47.0±18.7, range 23-86) to determine if trait aggression and trait impulsivity were related to frontal cortex 5-HT2A receptor binding (5-HT2AR) as measured with [(18)F]-altanserin PET imaging. Trait aggression and trait impulsivity were assessed with the Buss-Perry Aggression Questionnaire (AQ...

  3. Radiosynthesis and evaluation of 11C-CIMBI-5 as a 5-HT2A receptor agonist radioligand for PET

    DEFF Research Database (Denmark)

    Ettrup, Anders; Palner, Mikael; Gillings, Nicolas;

    2010-01-01

    PET tracers would, however, enable imaging of the active, high-affinity state of receptors, which may provide a more meaningful assessment of membrane-bound receptors. In this study, we radiolabel the high-affinity 5-HT(2A) receptor agonist 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2-[(11)C-OCH(3...

  4. Acute social defeat does not alter cerebral 5-HT2A receptor binding in male Wistar rats

    DEFF Research Database (Denmark)

    Visser, Anniek K D; Meerlo, Peter; Ettrup, Anders;

    2014-01-01

    suppressed growth, but did not affect anxiety-like behavior in an open field test. A positron emission tomography scan with the 5-HT2A R tracer [11C]MDL 100907 1 day and 3 weeks after defeat did not show significant changes in receptor binding. To verify these results, [3H]MDL 100907 binding assays were...

  5. Synthesis and structure-activity relationships of N-benzyl phenethylamines as 5-HT2A/2C agonists

    DEFF Research Database (Denmark)

    Hansen, Martin; Phonekeo, Karina; Paine, James S;

    2014-01-01

    N-benzyl substitution of 5-HT2A receptor agonists of the phenethylamine structural class of psychedelics (such as 4-bromo-2,5-dimethoxyphenethylamine, often referred to as 2C-B) confer a significant increase in binding affinity as well as functional activity of the receptor. We have prepared...

  6. The antidepressant 5-HT2A receptor antagonists pizotifen and cyproheptadine inhibit serotonin-enhanced platelet function.

    Directory of Open Access Journals (Sweden)

    Olivia A Lin

    Full Text Available There is considerable interest in defining new agents or targets for antithrombotic purposes. The 5-HT2A receptor is a G-protein coupled receptor (GPCR expressed on many cell types, and a known therapeutic target for many disease states. This serotonin receptor is also known to regulate platelet function. Thus, in our FDA-approved drug repurposing efforts, we investigated the antiplatelet activity of cyproheptadine and pizotifen, two antidepressant 5-HT2A Receptor antagonists. Our results revealed that cyproheptadine and pizotifen reversed serotonin-enhanced ADP-induced platelet aggregation in vitro and ex vivo. And the inhibitory effects of these two agents were found to be similar to that of EMD 281014, a 5-HT2A Receptor antagonist under development. In separate experiments, our studies revealed that these 5-HT2A receptor antagonists have the capacity to reduce serotonin-enhanced ADP-induced elevation in intracellular calcium levels and tyrosine phosphorylation. Using flow cytometry, we also observed that cyproheptadine, pizotifen, and EMD 281014 inhibited serotonin-enhanced ADP-induced phosphatidylserine (PS exposure, P-selectin expression, and glycoprotein IIb-IIIa activation. Furthermore, using a carotid artery thrombosis model, these agents prolonged the time for thrombotic occlusion in mice in vivo. Finally, the tail-bleeding time was investigated to assess the effect of cyproheptadine and pizotifen on hemostasis. Our findings indicated prolonged bleeding time in both cyproheptadine- and pizotifen-treated mice. Notably, the increases in occlusion and bleeding times associated with these two agents were comparable to that of EMD 281014, and to clopidogrel, a commonly used antiplatelet drug, again, in a fashion comparable to clopidogrel and EMD 281014. Collectively, our data indicate that the antidepressant 5-HT2A antagonists, cyproheptadine and pizotifen do exert antiplatelet and thromboprotective effects, but similar to clopidogrel and

  7. Serotonin 5-HT2A Receptor Function as a Contributing Factor to Both Neuropsychiatric and Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Charles D. Nichols

    2009-01-01

    Full Text Available There are high levels of comorbidity between neuropsychiatric and cardiovascular disorders. A key molecule central to both cognitive and cardiovascular function is the molecule serotonin. In the brain, serotonin modulates neuronal activity and is actively involved in mediating many cognitive functions and behaviors. In the periphery, serotonin is involved in vasoconstriction, inflammation, and cell growth, among other processes. It is hypothesized that one component of the serotonin system, the 5-HT2A receptor, is a common and contributing factor underlying aspects of the comorbidity between neuropsychiatric and cardiovascular disorders. Within the brain this receptor participates in processes such as cognition and working memory, been implicated in effective disorders such as schizophrenia, and mediate the primary effects of hallucinogenic drugs. In the periphery, 5-HT2A receptors have been linked to vasoconstriction and hypertension, and to inflammatory processes that can lead to atherosclerosis.

  8. Involvement of 5-HT2A receptors in MDMA reinforcement and cue-induced reinstatement of MDMA-seeking behaviour

    OpenAIRE

    Orejarena, María Juliana; Lanfumey, Laurence; Maldonado, Rafael; Robledo, Patricia

    2011-01-01

    The serotonergic system appears crucial for (??)-3,4-methylenedioxymethamphetamine (MDMA) reinforcing properties. Current evidence indicates that serotonin 5-HT2A receptors (5-HT2ARs) modulate mesolimbic dopamine (DA) activity and several behavioural responses related to the addictive properties of psychostimulants. This study evaluated the role of 5-HT2ARs in MDMA-induced reinforcement and hyperlocomotion, and the reinstatement of MDMA-seeking behaviour. Basal and MDMA-stimulated extracellul...

  9. Mismatch negativity generation in the human 5HT2A agonist and NMDA antagonist model of psychosis

    OpenAIRE

    Heekeren, K; Daumann, J.; Neukirch, A.; Stock, C.; Kawohl, W.; Norra, C; Waberski, T.; Gouzoulis-Mayfrank, E.

    2008-01-01

    RATIONALE: Many studies have reported deficits of mismatch negativity (MMN) in schizophrenic patients. Pharmacological challenges with hallucinogens in healthy humans are used as models for psychotic states. Previous studies reported a significant reduction of MMN after ketamine (N-methyl-D-aspartate acid [NMDA] antagonist model) but not after psilocybin (5HT2A agonist model). OBJECTIVES: The aim of the present study was to directly compare the two models of psychosis using an intraindividual...

  10. Chronic treatment with LY341495 decreases 5-HT(2A) receptor binding and hallucinogenic effects of LSD in mice.

    Science.gov (United States)

    Moreno, José L; Holloway, Terrell; Rayannavar, Vinayak; Sealfon, Stuart C; González-Maeso, Javier

    2013-03-01

    Hallucinogenic drugs, such as lysergic acid diethylamide (LSD), mescaline and psilocybin, alter perception and cognitive processes. All hallucinogenic drugs have in common a high affinity for the serotonin 5-HT(2A) receptor. Metabotropic glutamate 2/3 (mGlu2/3) receptor ligands show efficacy in modulating the cellular and behavioral responses induced by hallucinogenic drugs. Here, we explored the effect of chronic treatment with the mGlu2/3 receptor antagonist 2S-2-amino-2-(1S,2S-2-carboxycyclopropan-1-yl)-3-(xanth-9-yl)-propionic acid (LY341495) on the hallucinogenic-like effects induced by LSD (0.24mg/kg). Mice were chronically (21 days) treated with LY341495 (1.5mg/kg), or vehicle, and experiments were carried out one day after the last injection. Chronic treatment with LY341495 down-regulated [(3)H]ketanserin binding in somatosensory cortex of wild-type, but not mGlu2 knockout (KO), mice. Head-twitch behavior, and expression of c-fos, egr-1 and egr-2, which are responses induced by hallucinogenic 5-HT(2A) agonists, were found to be significantly decreased by chronic treatment with LY341495. These findings suggest that repeated blockade of the mGlu2 receptor by LY341495 results in reduced 5-HT(2A) receptor-dependent hallucinogenic effects of LSD.

  11. Association of the 5-HT2A receptor gene polymorphism 102T/C with ischemic stroke

    DEFF Research Database (Denmark)

    Olesen, Ole F; Bennike, Bente; Dam, Henrik;

    2006-01-01

    Serotonin (5-HT) has been implicated in a number of cardiovascular disorders due to its ability to induce vascular contraction and platelet aggregation through activation of the 5-HT2 receptor family. In this study, we investigated the association of stroke in a Scandinavian population with two c...... and stroke was significant in both males and females. There was no association between stroke and the -1438A/G polymorphism. Taken together, this study indicates that the 102T/C polymorphism in the 5-HT2A receptor gene could be an independent risk factor for developing stroke.......Serotonin (5-HT) has been implicated in a number of cardiovascular disorders due to its ability to induce vascular contraction and platelet aggregation through activation of the 5-HT2 receptor family. In this study, we investigated the association of stroke in a Scandinavian population with two...... common polymorphisms in the 5-HT2A receptor gene. The two polymorphisms under investigation, namely the 102T/C and the -1438A/G variations of the 5-HT2A receptor gene, were examined in a case control association study involving 99 stroke patients and a comparable number of controls. Among patients...

  12. Central Serotonin-2A (5-HT2A Receptor Dysfunction in Depression and Epilepsy: The Missing Link?

    Directory of Open Access Journals (Sweden)

    Bruno Pierre Guiard

    2015-03-01

    Full Text Available 5-Hydroxytryptamine 2A receptors (5-HT2A-Rs are G-protein coupled receptors. In agreement with their location in the brain, they have been implicated not only in various central physiological functions including memory, sleep, nociception, eating and reward behaviors, but also in many neuropsychiatric disorders. Interestingly, a bidirectional link between depression and epilepsy is suspected since patients with depression and especially suicide attempters have an increased seizure risk, while a significant percentage of epileptic patients suffer from depression. Such epidemiological data led us to hypothesize that both pathologies may share common anatomical and neurobiological alteration of the 5-HT2A signaling. After a brief presentation of the pharmacological properties of the 5-HT2A-Rs, this review illustrates how these receptors may directly or indirectly control neuronal excitability in most networks involved in depression and epilepsy through interactions with the monoaminergic, GABAergic and glutamatergic neurotransmissions. It also synthetizes the preclinical and clinical evidence demonstrating the role of these receptors in antidepressant and antiepileptic responses.

  13. Polimorfismos dos genes do receptor de serotonina (5-HT2A) e da catecol-O-metiltransferase (COMT): fatores desencadeantes da fibromialgia? Serotonin receptor (5-HT 2A) and catechol-O-methyltransferase (COMT) gene polymorphisms: Triggers of fibromyalgia?

    OpenAIRE

    Josie Budag Matsuda; Flávia Regina Barbosa; Lucas Junqueira Fernandes Morel; Suzelei de Castro França; Sonia Marli Zingaretti; Lucienir Maria da Silva; Ana Maria Soares Pereira; Mozart Marins; Ana Lúcia Fachin

    2010-01-01

    INTRODUÇÃO: A fibromialgia é uma síndrome reumática caracterizada por dor difusa e crônica associada a fadiga, insônia, ansiedade, depressão, perda de memória e tontura. Embora os mecanismos fisiológicos que controlam a fibromialgia não tenham sido estabelecidos, fatores neuroendócrinos, genéticos ou moleculares podem estar envolvidos. OBJETIVO: O objetivo do presente estudo foi caracterizar os polimorfismos dos genes do receptor de serotonina (5-HT2A) e da catecolO-metiltransferase (COMT) em...

  14. Gender and the use of hormonal contraception in women are not associated with cerebral cortical 5-HT 2A receptor binding

    DEFF Research Database (Denmark)

    Frokjaer, V G; Erritzoe, D; Madsen, J;

    2009-01-01

    Gender influences brain function including serotonergic neurotransmission, which may play a role in the well-known gender variations in vulnerability to mood and anxiety disorders. Even though hormonal replacement therapy in menopause is associated with globally increased cerebral 5-HT(2A) receptor...... binding it is not clear if gender or use of hormonal contraception exhibits associations with 5-HT(2A) receptor binding. We found no significant effect of gender on cortical 5-HT(2A) receptor binding (P=0.15, n=132). When adjusting for the personality trait neuroticism, known to be positively correlated...... to frontolimbic 5-HT(2A) receptor binding and to be more pronounced in women, again, the effect of gender was not significant (P=0.42, n=127). Also, the use of hormonal contraception (n=14) within the group of pre-menopausal women (total n=29) was not associated with cortical 5-HT(2A) receptor binding (P=0...

  15. Preliminary in vivo and ex vivo evaluation of the 5-HT2A imaging probe [18F]MH.MZ

    International Nuclear Information System (INIS)

    Introduction: The 5-HT2A receptor is one of the most interesting targets within the serotonergic system because it is involved in a number of important physiological processes and diseases. Methods: [18F]MH.MZ, a 5-HT2A antagonistic receptor ligand, is labeled by 18F-fluoroalkylation of the corresponding desmethyl analogue MDL 105725 with 2-[18F]fluoroethyltosylate ([18F]FETos). In vitro binding experiments were performed to test selectivity toward a broad spectrum of neuroreceptors by radioligand binding assays. Moreover, first micro-positron emission tomography (μPET) experiments, ex vivo organ biodistribution, blood cell and protein binding and brain metabolism studies of [18F]MH.MZ were carried out in rats. Results: [18F]MH.MZ showed a Ki of 3 nM toward the 5-HT2A receptor and no appreciable affinity for a variety of receptors and transporters. Ex vivo biodistribution as well as μPET showed highest brain uptake at ∼5 min p.i. and steady state after ∼30 min p.i. While [18F]MH.MZ undergoes extensive first-pass metabolism which significantly reduces its bioavailability, it is insignificantly metabolized within the brain. The binding potential in the rat frontal cortex is 1.45, whereas the cortex to cerebellum ratio was determined to be 2.7 after ∼30 min. Conclusion: Results from μPET measurements of [18F]MH.MZ are in no way inferior to data known for [11C]MDL 100907 at least in rats. [18F]MH.MZ appears to be a highly potent and selective serotonergic PET ligand in small animals.

  16. Effect of 5-HT2A and 5-HT2C receptors on temporal discrimination by mice.

    Science.gov (United States)

    Halberstadt, Adam L; Sindhunata, Ivan S; Scheffers, Kees; Flynn, Aaron D; Sharp, Richard F; Geyer, Mark A; Young, Jared W

    2016-08-01

    Timing deficits are observed in patients with schizophrenia. Serotonergic hallucinogens can also alter the subjective experience of time. Characterizing the mechanism through which the serotonergic system regulates timing will increase our understanding of the linkage between serotonin (5-HT) and schizophrenia, and will provide insight into the mechanism of action of hallucinogens. We investigated whether interval timing in mice is altered by hallucinogens and other 5-HT2 receptor ligands. C57BL/6J mice were trained to perform a discrete-trials temporal discrimination task. In the discrete-trials task, mice were presented with two levers after a variable interval. Responding on lever A was reinforced if the interval was 6.5 s. A 2-parameter logistic function was fitted to the proportional choice for lever B (%B responding), yielding estimates of the indifference point (T50) and the Weber fraction (a measure of timing precision). The 5-HT2A antagonist M100907 increased T50, whereas the 5-HT2C antagonist SB-242,084 reduced T50. The results indicate that 5-HT2A and 5-HT2C receptors have countervailing effects on the speed of the internal pacemaker. The hallucinogen 2,5-dimethoxy-4-iodoamphetamine (DOI; 3 mg/kg IP), a 5-HT2 agonist, flattened the response curve at long stimulus intervals and shifted it to the right, causing both T50 and the Weber fraction to increase. The effect of DOI was antagonized by M100907 (0.03 mg/kg SC) but was unaffected by SB-242,084 (0.1 mg/kg SC). Similar to DOI, the selective 5-HT2A agonist 25CN-NBOH (6 mg/kg SC) reduced %B responding at long stimulus intervals, and increased T50 and the Weber fraction. These results demonstrate that hallucinogens alter temporal perception in mice, effects that are mediated by the 5-HT2A receptor. It appears that 5-HT regulates temporal perception, suggesting that altered serotonergic signaling may contribute to the timing deficits observed in schizophrenia and other psychiatric disorders. PMID

  17. The effect of prolonged exposure to morphine on canine cerebral 5-HT2A receptors measured with (123)I-R91150 SPECT.

    Science.gov (United States)

    Adriaens, Antita; Polis, Ingeborgh; Vermeire, Simon; Waelbers, Tim; Croubels, Siska; Duchateau, Luc; Van Dorpe, Sylvia; Eersels, Jos; De Spiegeleer, Bart; Peremans, Kathelijne

    2014-07-01

    Down-stream neuronal alterations, including changes in the 5-HT-2A receptor system, play an important role in the etiology and treatment of depression. The present study examined the effect of prolonged opioid treatment on cerebral 5-HT2A receptors. Cerebral 5-HT2A receptor availability was estimated in seven healthy five-year-old female neutered Beagle dogs pre and post 10-day morphine treatment (oral sustained release morphine 20mg twice daily for 10 days) with (123)I-R-91150, a 5-HT2A selective radioligand, and SPECT. 5-HT2A receptor binding indices (BI) for the frontal, parietal, temporal and occipital cortex and the subcortical region were calculated. Statistical analysis was performed using a linear mixed-effect model with treatment as fixed effect and dog as random effect. Morphine treatment significantly (P≤0.05) lowered 5-HT2A BIs in the right and left frontal cortex, the right and left temporal cortex, the right and left parietal cortex, and the subcortical region. The decreased cerebral 5-HT2A receptor availability following prolonged morphine exposure provides further evidence for an interaction between the opioid and serotonergic system.

  18. C-(4,5,6-trimethoxyindan-1-yl)methanamine: a mescaline analogue designed using a homology model of the 5-HT2A receptor.

    Science.gov (United States)

    McLean, Thomas H; Chambers, James J; Parrish, Jason C; Braden, Michael R; Marona-Lewicka, Danuta; Kurrasch-Orbaugh, Deborah; Nichols, David E

    2006-07-13

    A conformationally restricted analogue of mescaline, C-(4,5,6-trimethoxyindan-1-yl)-methanamine, was designed using a 5-HT(2A) receptor homology model. The compound possessed 3-fold higher affinity and potency than and efficacy equal to that of mescaline at the 5-HT(2A) receptor. The new analogue substituted fully for LSD in drug discrimination studies and was 5-fold more potent than mescaline. Resolution of this analogue into its enantiomers corroborated the docking experiments, showing the R-(+) isomer to have higher affinity and potency and to have efficacy similar to that of mescaline at the 5-HT(2A) receptor.

  19. Synthesis and pharmacological evaluation of N-benzyl substituted 4-bromo-2,5-dimethoxyphenethylamines as 5-HT2A/2C partial agonists

    DEFF Research Database (Denmark)

    Hansen, Martin; Jacobsen, Stine Engesgaard; Plunkett, Shane;

    2015-01-01

    N-Benzyl substitution of phenethylamine 5-HT2A receptor agonists has dramatic effects on binding affinity, receptor selectivity and agonist activity. In this paper we examine how affinity for the 5-HT2A/2C receptors are influenced by N-benzyl substitution of 4-bromo-2,5-dimethoxyphenethylamine......-affinity ligands were identified and assayed for functional activity at the 5-HT2A and 5-HT2C receptor, and they were generally found to be less efficacious agonists than previously reported N-benzyl phenethylamines....

  20. Polimorfismos dos genes do receptor de serotonina (5-HT2A e da catecol-O-metiltransferase (COMT: fatores desencadeantes da fibromialgia? Serotonin receptor (5-HT 2A and catechol-O-methyltransferase (COMT gene polymorphisms: Triggers of fibromyalgia?

    Directory of Open Access Journals (Sweden)

    Josie Budag Matsuda

    2010-04-01

    Full Text Available INTRODUÇÃO: A fibromialgia é uma síndrome reumática caracterizada por dor difusa e crônica associada a fadiga, insônia, ansiedade, depressão, perda de memória e tontura. Embora os mecanismos fisiológicos que controlam a fibromialgia não tenham sido estabelecidos, fatores neuroendócrinos, genéticos ou moleculares podem estar envolvidos. OBJETIVO: O objetivo do presente estudo foi caracterizar os polimorfismos dos genes do receptor de serotonina (5-HT2A e da catecolO-metiltransferase (COMT em pacientes brasileiros com fibromialgia, a fim de avaliar sua participação na etiologia da doença. MATERIAL E MÉTODOS: O DNA genômico extraído de 102 amostras de sangue (51 pacientes, 51 controles foi usado para a caracterização molecular dos polimorfismos dos genes 5-HT2A e COMT, por meio de PCR-RFLP. RESULTADOS: A análise molecular dos polimorfismos do gene 5-HT2A demonstrou frequências de 25,49% C/C, 49,02% T/C e 25,49% T/T, nos pacientes com fibromialgia, e 17,65% C/C, 62,74% T/C e 19,61% T/T, no grupo controle, não apresentando diferença significativa entre o grupo de pacientes e o grupo controle. Os polimorfismos do gene da COMT em pacientes com fibromialgia apresentaram uma frequência de 17,65% e 45,10% para os genótipos H/H e L/H, respectivamente. No grupo controle, as frequências foram de 29,42%, para H/H, e 60,78%, para L/H, sem diferença significativa entre ambos os grupos. Entretanto, houve diferença significativa na frequência do genótipo L/L em pacientes (37,25% e controles (9,8%, o que permitiu a diferenciação entre os dois grupos. CONCLUSÃO: A frequência do genótipo L/L foi maior nos pacientes com fibromialgia. Apesar de a fibromialgia envolver uma situação poligênica e fatores ambientais, o estudo molecular do SNP rs4680 do gene da COMT pode auxiliar a identificação de indivíduos suscetíveis.INTRODUCTION: Fibromyalgia is a rheumatic syndrome characterized by diffuse and chronic pain associated with

  1. Cerebral 5-HT2A receptor and serotonin transporter binding in humans are not affected by the val66met BDNF polymorphism status or blood BDNF levels

    DEFF Research Database (Denmark)

    Klein, Anders Bue; Trajkovska, Viktorija; Erritzoe, David;

    2010-01-01

    Recent studies have proposed an interrelation between the brain-derived neurotrophic factor (BDNF) val66met polymorphism and the serotonin system. In this study, we investigated whether the BDNF val66met polymorphism or blood BDNF levels are associated with cerebral 5-hydroxytryptamine 2A (5-HT(2A......)) receptor or serotonin transporter (SERT) binding in healthy subjects. No statistically significant differences in 5-HT(2A) receptor or SERT binding were found between the val/val and met carriers, nor were blood BDNF values associated with SERT binding or 5-HT(2A) receptor binding. In conclusion, val66met...... BDNF polymorphism status is not associated with changes in the serotonergic system. Moreover, BDNF levels in blood do not correlate with either 5-HT(2A) or SERT binding....

  2. 5-HT2A Receptor Binding in the Frontal Cortex of Parkinson's Disease Patients and Alpha-Synuclein Overexpressing Mice: A Postmortem Study.

    Science.gov (United States)

    Rasmussen, Nadja Bredo; Olesen, Mikkel Vestergaard; Brudek, Tomasz; Plenge, Per; Klein, Anders Bue; Westin, Jenny E; Fog, Karina; Wörtwein, Gitta; Aznar, Susana

    2016-01-01

    The 5-HT2A receptor is highly involved in aspects of cognition and executive function and seen to be affected in neurodegenerative diseases like Alzheimer's disease and related to the disease pathology. Even though Parkinson's disease (PD) is primarily a motor disorder, reports of impaired executive function are also steadily being associated with this disease. Not much is known about the pathophysiology behind this. The aim of this study was thereby twofold: (1) to investigate 5-HT2A receptor binding levels in Parkinson's brains and (2) to investigate whether PD associated pathology, alpha-synuclein (AS) overexpression, could be associated with 5-HT2A alterations. Binding density for the 5-HT2A-specific radioligand [(3)H]-MDL 100.907 was measured in membrane suspensions of frontal cortex tissue from PD patients. Protein levels of AS were further measured using western blotting. Results showed higher AS levels accompanied by increased 5-HT2A receptor binding in PD brains. In a separate study, we looked for changes in 5-HT2A receptors in the prefrontal cortex in 52-week-old transgenic mice overexpressing human AS. We performed region-specific 5-HT2A receptor binding measurements followed by gene expression analysis. The transgenic mice showed lower 5-HT2A binding in the frontal association cortex that was not accompanied by changes in gene expression levels. This study is one of the first to look at differences in serotonin receptor levels in PD and in relation to AS overexpression. PMID:27579212

  3. 5-HT2A Receptor Binding in the Frontal Cortex of Parkinson’s Disease Patients and Alpha-Synuclein Overexpressing Mice: A Postmortem Study

    Directory of Open Access Journals (Sweden)

    Nadja Bredo Rasmussen

    2016-01-01

    Full Text Available The 5-HT2A receptor is highly involved in aspects of cognition and executive function and seen to be affected in neurodegenerative diseases like Alzheimer’s disease and related to the disease pathology. Even though Parkinson’s disease (PD is primarily a motor disorder, reports of impaired executive function are also steadily being associated with this disease. Not much is known about the pathophysiology behind this. The aim of this study was thereby twofold: (1 to investigate 5-HT2A receptor binding levels in Parkinson’s brains and (2 to investigate whether PD associated pathology, alpha-synuclein (AS overexpression, could be associated with 5-HT2A alterations. Binding density for the 5-HT2A-specific radioligand [3H]-MDL 100.907 was measured in membrane suspensions of frontal cortex tissue from PD patients. Protein levels of AS were further measured using western blotting. Results showed higher AS levels accompanied by increased 5-HT2A receptor binding in PD brains. In a separate study, we looked for changes in 5-HT2A receptors in the prefrontal cortex in 52-week-old transgenic mice overexpressing human AS. We performed region-specific 5-HT2A receptor binding measurements followed by gene expression analysis. The transgenic mice showed lower 5-HT2A binding in the frontal association cortex that was not accompanied by changes in gene expression levels. This study is one of the first to look at differences in serotonin receptor levels in PD and in relation to AS overexpression.

  4. [18F]altanserin binding to human 5HT2A receptors is unaltered after citalopram and pindolol challenge

    DEFF Research Database (Denmark)

    Pinborg, L. H.; Adams, K. H.; Yndsgaard, S;

    2004-01-01

    /infusion approach designed for attaining steady state in blood and brain 2 hours after the initial [18F]altanserin administration. Three hours after commencement of radiotracer administration, 0.25 mg/kg of the selective serotonin reuptake inhibitor, citalopram (Lundbeck, Valby, Denmark), was administered to all...... condition (120 to 180 minutes) was compared with the stimulated condition (195 to 300 minutes). Despite a pronounced increase in plasma prolactin and two subjects reporting hot flushes compatible with an 5-HT-induced adverse effect, cortical [18F]altanserin binding was insensitive to the citalopram...... challenge, even after pindolol pretreatment. The biochemical and cellular events possibly affecting the unsuccessful translation of the citalopram/pindolol challenge into a change in 5-HT2A receptor binding of [18F]altanserin are discussed...

  5. Effects of dominance status on conditioned defeat and expression of 5-HT1A and 5-HT2A receptors.

    Science.gov (United States)

    Morrison, Kathleen E; Swallows, Cody L; Cooper, Matthew A

    2011-08-01

    Past experience can alter how individuals respond to stressful events. The brain serotonin system is a key factor modulating stress-related behavior and may contribute to individual variation in coping styles. In this study we investigated whether dominant and subordinate hamsters respond differently to social defeat and whether their behavioral responses are associated with changes in 5-HT1A and 5-HT2A receptor immunoreactivity in several limbic brain regions. We paired weight-matched hamsters in daily aggressive encounters for two weeks so that they formed a stable dominance relationship. We also included controls that were exposed to an empty cage each day for two weeks. Twenty-four hours after the final pairing or empty cage exposure, subjects were socially defeated in 3, 5-min encounters with a more aggressive hamster. Twenty-four hours after social defeat, animals were tested for conditioned defeat in a 5-min social interaction test with a non-aggressive intruder. We collected brains following conditioned defeat testing and performed immunohistochemistry for 5-HT1A and 5-HT2A receptors. We found that dominants showed less submissive and defensive behavior at conditioned defeat testing compared to both subordinates and controls. Additionally, both dominants and subordinates had an increased number of 5-HT1A immunopositive cells in the basolateral amygdala compared to controls. Subordinates also had more 5-HT1A immunopositive cells in the dorsal medial amygdala than did controls. Finally, dominants had fewer 5-HT1A immunopositive cells in the paraventricular nucleus of the hypothalamus compared to controls. Our results indicate that dominant social status results in a blunted conditioned defeat response and a distinct pattern of 5-HT1A receptor expression, which may contribute to resistance to conditioned defeat.

  6. Synthesis and evaluation of 18F-labeled 5-HT2A receptor agonists as PET ligands

    DEFF Research Database (Denmark)

    Herth, Matthias M; Petersen, Ida Nymann; Hansen, Hanne Demant;

    2016-01-01

    and processes in the human brain and several 5-HT2AR PET antagonist radioligands are available. In contrast to an antagonist radioligand, an agonist radioligand should be able to image the population of functional receptors, i.e., those capable of inducing neuroreceptor signaling. Recently, we successfully...... developed and validated the first 5-HT2AR agonist PET tracer, [(11)C]Cimbi-36, for neuroimaging in humans and herein disclose some of our efforts to develop an (18)F-labeled 5-HT2AR agonist PET-ligand. METHODS AND RESULTS: Three fluorine containing derivatives of Cimbi-36 were synthesized and found...... to be potent 5-HT2A agonists. (18)F-labeling of the appropriate precursors was performed using [(18)F]FETos, typically yielding 0.2-2.0GBq and specific activities of 40-120GBq/μmol. PET studies in Danish landrace pigs revealed that [(18)F]1 displayed brain uptake in 5-HT2AR rich regions. However, high uptake...

  7. Potential role of cortical 5-HT(2A) receptors in the anxiolytic action of cyamemazine in benzodiazepine withdrawal.

    Science.gov (United States)

    Benyamina, Amine; Naassila, Mickaël; Bourin, Michel

    2012-07-30

    The antipsychotic cyamemazine is a potent serotonin 5-HT(2A) receptor (5-HT(2AR)) antagonist. A positron emission tomography (PET) study in human patients showed that therapeutic doses of cyamemazine produced near saturation of 5-HT(2AR) occupancy in the frontal cortex, whereas dopamine D(2) occupancy remained below the level for motor side effects observed with typical antipsychotics. Recently, numerous studies have revealed the involvement of 5-HT(2AR) in the pathophysiology of anxiety and a double-blind, randomized clinical trial showed similar efficacy of cyamemazine and bromazepam in reducing the anxiety associated with benzodiazepine withdrawal. Therefore, we reviewed the above articles about 5-HT(2AR) and anxiety in order to understand better the anxiolytic mechanisms of cyamemazine in benzodiazepine withdrawal. The 5-HT(2AR) is the most abundant serotonin receptor subtype in the cortex. Non-pharmacological studies with antisense oligodeoxynucleotides and genetically modified mice clearly showed that cortical 5-HT(2AR) signaling positively modulates anxiety-like behavior. With a few exceptions, most other studies reviewed here further support this view. Therefore, the anxiolytic efficacy of cyamemazine in benzodiazepine withdrawal can be due to a 5-HT(2AR) antagonistic activity at the cortical level.

  8. Maternal lipopolysaccharide treatment differentially affects 5-HT(2A) and mGlu2/3 receptor function in the adult male and female rat offspring.

    Science.gov (United States)

    Wischhof, Lena; Irrsack, Ellen; Dietz, Frank; Koch, Michael

    2015-10-01

    Maternal infection during pregnancy increases the risk for the offspring to develop schizophrenia. However, it is still not fully understood which biochemical mechanisms are responsible for the emergence of neuropsychiatric symptoms following prenatal immune activation. The serotonin (5-hydroxytryptamine, 5-HT) and glutamate system have prominently been associated with the schizophrenia pathophysiology but also with the mechanism of antipsychotic drug actions. Here, we investigated the behavioral and cellular response to 5-HT2A and metabotropic glutamate (mGlu)2/3 receptor stimulation in male and female offspring born to lipopolysaccharide (LPS)-treated mothers. Additionally, we assessed protein expression levels of prefrontal 5-HT2A and mGlu2 receptors. Prenatally LPS-exposed male and female offspring showed locomotor hyperactivity and increased head-twitch behavior in response to the 5-HT2A receptor agonist DOI. In LPS-exposed male offspring, the mGlu2/3 receptor agonist LY379268 failed to reduce DOI-induced prepulse inhibition deficits. In LPS-males, the behavioral changes were further accompanied by enhanced DOI-induced c-Fos protein expression and an up-regulation of prefrontal 5-HT2A receptors. No changes in either 5-HT2A or mGlu2 receptor protein levels were found in female offspring. Our data support the hypothesis of an involvement of maternal infection during pregnancy contributing, at least partially, to the pathology of schizophrenia. Identifying biochemical alterations that parallel the behavioral deficits may help to improve therapeutic strategies in the treatment of this mental illness. Since most studies in rodents almost exclusively include male subjects, our data further contribute to elucidating possible gender differences in the effects of prenatal infection on 5-HT2A and mGlu2/3 receptor function. PMID:26051401

  9. Orbitofrontal cortex 5-HT2A receptor mediates chronic stress-induced depressive-like behaviors and alterations of spine density and Kalirin7.

    Science.gov (United States)

    Xu, Chang; Ma, Xin-Ming; Chen, Hui-Bin; Zhou, Meng-He; Qiao, Hui; An, Shu-Cheng

    2016-10-01

    Neuroimaging studies show that patients with major depression have reduced volume of the orbitofrontal cortex (OFC). Although the serotonin (5-HT) 2A receptor, which is abundant in the OFC, has been implicated in depression, the underlying mechanisms in the development of stress-induced depression remain unclear. Kalirin-7 (Kal7) is an essential component of mature excitatory synapses for maintaining dendritic spines density, size and synaptic functions. The aim of this study was to investigate the role of orbitofrontal 5-HT and 5-HT2A receptors in depressive-like behaviors and their associations with Kal7 and dendritic spines using chronic unpredictable mild stress (CUMS), an established animal model of depression. CUMS had no effect on the levels of 5-HT or the 5-HT2A receptor in the OFC. However, CUMS or microinjection of the 5-HT2A/2C receptor agonist (±)-1-(2, 5-Dimethoxy-4-iodophenyl)- 2-aminopropane hydrochloride (DOI, 5 μg/0.5 μL) into the OFC induced depressive-like behaviors, including anhedonia in the sucrose preference test and behavioral despair in the tail suspension test, a significant reduction in body weight gain and locomotor activity in the open field test, which were accompanied by decreased expression of Kal7 and PSD95 as well as decreased density of dendritic spines in the OFC. These alterations induced by CUMS were reversed by pretreatment with the 5-HT2A receptor antagonist Ketanserin (Ket, 5 μg/0.5 μL into the OFC). These results suggest that CUMS alters structural plasticity through activation of the orbital 5-HT2A receptor and is associated with decreased expression of Kal7, thereby resulting in depressive-like behaviors in rats, suggesting an important role of Kal7 in the OFC in depression. PMID:26921771

  10. Tolerance to LSD and DOB induced shaking behaviour: differential adaptations of frontocortical 5-HT(2A) and glutamate receptor binding sites.

    Science.gov (United States)

    Buchborn, Tobias; Schröder, Helmut; Dieterich, Daniela C; Grecksch, Gisela; Höllt, Volker

    2015-03-15

    Serotonergic hallucinogens, such as lysergic acid diethylamide (LSD) and dimethoxy-bromoamphetamine (DOB), provoke stereotype-like shaking behaviour in rodents, which is hypothesised to engage frontocortical glutamate receptor activation secondary to serotonin2A (5-HT2A) related glutamate release. Challenging this hypothesis, we here investigate whether tolerance to LSD and DOB correlates with frontocortical adaptations of 5-HT2A and/or overall-glutamate binding sites. LSD and DOB (0.025 and 0.25 mg/kg, i.p.) induce a ketanserin-sensitive (0.5 mg/kg, i.p., 30-min pretreatment) increase in shaking behaviour (including head twitches and wet dog shakes), which with repeated application (7× in 4 ds) is undermined by tolerance. Tolerance to DOB, as indexed by DOB-sensitive [(3)H]spiroperidol and DOB induced [(35)S]GTP-gamma-S binding, is accompanied by a frontocortical decrease in 5-HT2A binding sites and 5-HT2 signalling, respectively; glutamate-sensitive [(3)H]glutamate binding sites, in contrast, remain unchanged. As to LSD, 5-HT2 signalling and 5-HT2A binding, respectively, are not or only marginally affected, yet [(3)H]glutamate binding is significantly decreased. Correlation analysis interrelates tolerance to DOB to the reduced 5-HT2A (r=.80) as well as the unchanged [(3)H]glutamate binding sites (r=.84); tolerance to LSD, as opposed, shares variance with the reduction in [(3)H]glutamate binding sites only (r=.86). Given that DOB and LSD both induce tolerance, one correlating with 5-HT2A, the other with glutamate receptor adaptations, it might be inferred that tolerance can arise at either level. That is, if a hallucinogen (like LSD in our study) fails to induce 5-HT2A (down-)regulation, glutamate receptors (activated postsynaptic to 5-HT2A related glutamate release) might instead adapt and thus prevent further overstimulation of the cortex.

  11. Lack of Association between the Serotonin Transporter (5-HTT) and Serotonin Receptor (5-HT2A) Gene Polymorphisms with Smoking Behavior among Malaysian Malays

    OpenAIRE

    Rozak, Nur Iwani A; Ahmad, Imran; Gan, Siew Hua; Abu Bakar, Ruzilawati

    2014-01-01

    Abstract An insertion/deletion polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) and a polymorphism (rs6313) in the serotonin 2A receptor gene (5-HT2A) have previously been linked to smoking behavior. The objective of this study was to determine the possible association of the 5-HTTLPR and 5-HT2A gene polymorphisms with smoking behavior within a population of Malaysian male smokers (n=248) and non-smokers (n=248). The 5-HTTLPR genotypes were determined using the...

  12. Cartography of 5-HT1A and 5-HT2A Receptor Subtypes in Prefrontal Cortex and Its Projections.

    Science.gov (United States)

    Mengod, Guadalupe; Palacios, José M; Cortés, Roser

    2015-07-15

    Since the development of chemical neuroanatomical tools in the 1960s, a tremendous wealth of information has been generated on the anatomical components of the serotonergic system, at the microscopic level in the brain including the prefrontal cortex (PFC). The PFC receives a widespread distribution of serotonin (5-hydroxytryptamine, 5-HT) terminals from the median and dorsal raphe nuclei. 5-HT receptors were first visualized using radioligand autoradiography in the late 1980s and early 1990s and showed, in contrast to 5-HT innervation, a differential distribution of binding sites associated with different 5-HT receptor subtypes. Due to the cloning of the different 5-HT receptor subtype genes in the late 1980s and early 1990s, it was possible, using in situ hybridization histochemistry, to localize cells expressing mRNA for these receptors. Double in situ hybridization histochemistry and immunohistochemistry allowed for the chemical characterization of the phenotype of cells expressing 5-HT receptors. Tract tracing technology allowed a detailed cartography of the neuronal connections of PFC and other brain areas. Based on these data, maps have been constructed that reflect our current understanding of the different circuits where 5-HT receptors can modulate the electrophysiological, pharmacological, and behavioral functions of the PFC. We will review current knowledge regarding the cellular localization of 5-HT1A and 5-HT2A receptors in mammalian PFC and their possible functions in the neuronal circuits of the PFC. We will discuss data generated in our laboratory as well as in others, focusing on localization in the pyramidal and GABAergic neuronal cell populations in different mammalian species using molecular neuroanatomy and on the connections with other brain regions.

  13. Effect of fluvoxamine on platelet 5-HT2A receptors as studied by [3H]lysergic acid diethylamide ([3H]LSD) binding in healthy volunteers.

    Science.gov (United States)

    Spigset, O; Mjörndal, T

    1997-09-01

    Alterations in platelet 5-HT2A receptor characteristics have been reported in major depression as well as in other psychiatric diseases, and some effort has been made to utilize platelet 5-HT2A receptor status as a biological correlate to antidepressant drug response. In order to investigate whether treatment with a selective serotonin reuptake inhibitor affects platelet 5-HT2A receptors, we have studied platelet [3H]lysergic acid diethylamide ([3H]LSD) binding in healthy subjects treated with fluvoxamine in increasing dosage once weekly for 4 weeks. After 1 week of fluvoxamine treatment (25 mg/day), both Bmax and Kd were significantly lower than before the start of the treatment (19.9 versus 25.5 fmol/mg protein, P = 0.005 for Bmax; 0.45 versus 0.93 nM, P = 0.006 for Kd). Bmax returned to baseline during week 2, whereas Kd was lower than the baseline value throughout the treatment period. After discontinuation of fluvoxamine treatment, there was a significant increase in Kd (0.50 nM before discontinuation vs. 1.14 nM after discontinuation; P = 0.001), but not in Bmax. The study demonstrates that fluvoxamine affects platelet 5-HT2A receptor status irrespective of underlying psychiatric disease, and that this effect is evident already after 1 week at a subtherapeutic fluvoxamine dose.

  14. Selective immunolesion of cholinergic neurons leads to long-term changes in 5-HT2A receptor levels in hippocampus and frontal cortex

    DEFF Research Database (Denmark)

    Severino, Maurizio; Pedersen, Anja F; Trajkovska, Viktorija;

    2007-01-01

    Although loss of cholinergic neurons in the basal forebrain is considered a key initial feature in Alzheimer's disease (AD), changes in other transmitter systems, including serotonin and 5-HT(2A) receptors, are also associated with early AD. The aim of this study was to investigate whether elimin...

  15. A database of [(18)F]-altanserin binding to 5-HT(2A) receptors in normal volunteers: normative data and relationship to physiological and demographic variables

    DEFF Research Database (Denmark)

    Adams, Karen H; Pinborg, Lars H; Svarer, Claus;

    2004-01-01

    This study presents the results of an analysis of 5-hydroxytryptamine (5-HT)(2A) receptors in 52 healthy subjects. Thirty men and twenty-two women aged between 21 and 79 years were investigated with magnetic resonance imaging (MRI) and [(18)F]-altanserin positron emission tomography (PET). The di......This study presents the results of an analysis of 5-hydroxytryptamine (5-HT)(2A) receptors in 52 healthy subjects. Thirty men and twenty-two women aged between 21 and 79 years were investigated with magnetic resonance imaging (MRI) and [(18)F]-altanserin positron emission tomography (PET...... brain was in agreement with existing in vitro post-mortem human 5-HT(2A) data. Apart from nonspecific cerebellar binding (DV(2)), there was no gender difference in 5-HT(2A) binding. A positive correlation between cerebellar binding and age was observed and negative correlations between age and DV(3......)' were found in all cortical regions, except occipital cortex, corresponding to a decrease in DV(3)' of 6% or 4% per decade with cerebellum or pons as reference regions, respectively. In several temporal and frontal cortical regions, positive correlations were found between body mass index (BMI) and DV(3...

  16. Limited participation of 5-HT1A and 5-HT2A/2C receptors in the clozapine-induced Fos-protein expression in rat forebrain regions

    NARCIS (Netherlands)

    Sebens, JB; Kuipers, SD; Koch, T; Ter Horst, GJ; Korf, J

    2000-01-01

    Through the development of tolerance following long-term clozapine treatment, we investigated whether 5-HT1A and 5-HT2A/2C receptors participate in the clozapine-induced Fos-protein expression in the rat forebrain. Tolerance exists when the acutely increased Fos responses to a challenge dose of the

  17. 5-HT2A/5-HT2C receptor pharmacology and intrinsic clearance of N-benzylphenethylamines modified at the primary site of metabolism

    DEFF Research Database (Denmark)

    Leth-Petersen, Sebastian; Petersen, Ida Nymann; Jensen, Anders A;

    2016-01-01

    The toxic hallucinogen 25B-NBOMe is very rapidly degraded by human liver microsomes and has low oral bioavailability. Herein we report on the synthesis, microsomal stability and 5-HT2A/5-HT2C receptor profile of novel analogs of 25B-NBOMe modified at the primary site of metabolism. Although...

  18. Direct comparison of [18F]MH.MZ and [18F]altanserin for 5-HT2A receptor imaging with PET

    DEFF Research Database (Denmark)

    Hansen, Hanne Demant; Ettrup, Anders; Herth, Matthias Manfred;

    2013-01-01

    Imaging the cerebral serotonin 2A (5-HT(2A) ) receptors with positron emission tomography (PET) has been carried out in humans with [(11) C]MDL 100907 and [(18) F]altanserin. Recently, the MDL 100907 analogue [(18) F]MH.MZ was developed combining the selectivity profile of MDL 100907 and the favo....... Synapse, 2013. © 2013 Wiley Periodicals, Inc....

  19. A nonlinear relationship between cerebral serotonin transporter and 5-HT(2A) receptor binding: an in vivo molecular imaging study in humans

    DEFF Research Database (Denmark)

    Erritzoe, David; Holst, Klaus; Frokjaer, Vibe G.;

    2010-01-01

    Serotonergic neurotransmission is involved in the regulation of physiological functions such as mood, sleep, memory, and appetite. Within the serotonin transmitter system, both the postsynaptically located serotonin 2A (5-HT2A) receptor and the presynaptic serotonin transporter (SERT) are sensitive...

  20. 3,4-methylenedioxymethamphetamine increases excitability in the dentate gyrus: role of 5HT2A receptor-induced PGE2 signaling.

    Science.gov (United States)

    Collins, Stuart A; Huff, Courtney; Chiaia, Nicolas; Gudelsky, Gary A; Yamamoto, Bryan K

    2016-03-01

    3,4-methylenedioxymethamphetamine (MDMA) is a widely abused psychostimulant, which causes release of serotonin in various forebrain regions. Recently, we reported that MDMA increases extracellular glutamate concentrations in the dentate gyrus, via activation of 5HT2A receptors. We examined the role of prostaglandin signaling in mediating the effects of 5HT2A receptor activation on the increases in extracellular glutamate and the subsequent long-term loss of parvalbumin interneurons in the dentate gyrus caused by MDMA. Administration of MDMA into the dentate gyrus of rats increased PGE2 concentrations which was prevented by coadministration of MDL100907, a 5HT2A receptor antagonist. MDMA-induced increases in extracellular glutamate were inhibited by local administration of SC-51089, an inhibitor of the EP1 prostaglandin receptor. Systemic administration of SC-51089 during injections of MDMA prevented the decreases in parvalbumin interneurons observed 10 days later. The loss of parvalbumin immunoreactivity after MDMA exposure coincided with a decrease in paired-pulse inhibition and afterdischarge threshold in the dentate gyrus. These changes were prevented by inhibition of EP1 and 5HT2A receptors during MDMA. Additional experiments revealed an increased susceptibility to kainic acid-induced seizures in MDMA-treated rats, which could be prevented with SC51089 treatments during MDMA exposure. Overall, these findings suggest that 5HT2A receptors mediate MDMA-induced PGE2 signaling and subsequent increases in glutamate. This signaling mediates parvalbumin cell losses as well as physiologic changes in the dentate gyrus, suggesting that the lack of the inhibition provided by these neurons increases the excitability within the dentate gyrus of MDMA-treated rats. We hypothesized that the widely abused psychostimulant MDMA causes a loss of parvalbumin (PV) cells and increases excitability in the dentate gyrus. MDMA increases serotonin (5HT) release and activates 5HT2A

  1. Distribution of serotonin 5-HT2A and 5-HT7 receptors in the Onuf's nucleus of the rat spinal cord

    Institute of Scientific and Technical Information of China (English)

    Fanqing Zeng; Chen Xu; Ge Xu

    2008-01-01

    BACKGROUND: Motoneurons from the Onuf's nucleus of the spinal cord, which innervate the striated muscle of the pelvic floor, play an important role in erection, ejaculation, and urine control. Serotonin (5-hydroxytryptamine, 5-HT) regulates motoneuron activity from the Onuf's nucleus of the spinal cord.However, few studies exist that describe 5-HT receptor distribution in the Onuf's nucleus. In addition, the nature of the effects of 5-HT receptor on the innervating striated muscle of the pelvic floor is controversial.OBJECTIVE: To investigate the distribution of serotonin 5-HT2A and 5-HT7 receptors in motoneurons of Onuf's nucleus in the spinal cord of male rats, and to analyze the relationship of 5-HT2A and 5-H7 receptors to central modulation of urogenital function.DESIGN, TIME AND SETTING: The neural morphology experiment was performed at the Ultramicrostructure Laboratory of Reproductive Medicine, Basic Medical College, Chongqing Medical University, China from April to December 2007.MATERIALS: Ten adult, Sprague Dawley rats (eight males and two females) were randomly divided into a gender control group (n = 4,50% male and 50% female) and a retrograde tracing group (n = 6, 100% male).Recombinant pseudorabies virus (PRV-152) was provided by Professor LW Enquist from Princeton University, USA. Rabbit anti-5-HT2A and 5-HT7 receptor antibodies were purchased from Diasorin, France.METHODS: In the gender control group, the spinal L5-6segments were harvested, sliced, and then incubated antibodies specific against 5-HT2A or 5-HT7 receptors for immunohistochemical staining. In the retrograde tracing group, PRV-152 was separately injected into the right ischiocavernosus (ischiocavernosus subgroup,n = 3) and the fight external urethral sphincter (external urethral sphincter subgroup, n = 3). Four days after injection, L5-6 segments were harvested, sliced, and incubated with antibodies specific against 5-HT2A or 5-HT7 receptors for double-labeling immunofluoresccnce

  2. Maternal aggression in Wistar rats: effect of 5-HT2A/2C receptor agonist and antagonist microinjected into the dorsal periaqueductal gray matter and medial septum

    Directory of Open Access Journals (Sweden)

    Almeida R.M.M. de

    2005-01-01

    Full Text Available The objective of the present study was to assess the role of the 5-HT2A/2C receptor at two specific brain sites, i.e., the dorsal periaqueductal gray matter (DPAG and the medial septal (MS area, in maternal aggressive behavior after the microinjection of either a 5-HT2A/2C receptor agonist or antagonist. Female Wistar rats were microinjected on the 7th postpartum day with the selective agonist alpha-methyl-5-hydroxytryptamine maleate (5-HT2A/2C or the antagonist 5-HT2A/2C, ketanserin. The agonist was injected into the DPAG at 0.2 (N = 9, 0.5 (N = 10, and 1.0 µg/0.2 µl (N = 9, and the antagonist was injected at 1.0 µg/0.2 µl (N = 9. The agonist was injected into the medial septal area (MS at 0.2 (N = 9, 0.5 (N = 7, and 1.0 µg/0.2 µl (N = 6 and the antagonist was injected at 1.0 µg/0.2 µl (N = 5. For the control, saline was injected into the DPAG (N = 7 and the MS (N = 12. Both areas are related to aggressive behavior and contain a high density of 5-HT receptors. Non-aggressive behaviors such as horizontal locomotion (walking and social investigation and aggressive behaviors such as lateral threat (aggressive posture, attacks (frontal and lateral, and biting the intruder were analyzed when a male intruder was placed into the female resident's cage. For each brain area studied, the frequency of the behaviors was compared among the various treatments by analysis of variance. The results showed a decrease in maternal aggressive behavior (number of bites directed at the intruder after microinjection of the agonist at 0.2 and 1.0 µg/0.2 µl (1.6 ± 0.7 and 0.9 ± 0.3 into the DPAG compared to the saline group (5.5 ± 1.1. There was no dose-response relationship with the agonist. The present findings suggest that the 5-HT2A/2C receptor agonist has an inhibitory effect on maternal aggressive behavior when microinjected into the DPAG and no effect when microinjected into the MS. Ketanserin (1.0 µg/0.2 µl decreased locomotion when microinjected

  3. Abeta(1-42) injection causes memory impairment, lowered cortical and serum BDNF levels, and decreased hippocampal 5-HT(2A) levels

    DEFF Research Database (Denmark)

    Christensen, R; Marcussen, Anders Bue; Wörtwein, Gitta;

    2008-01-01

    Aggregation of the beta-amyloid protein (Abeta) is a hallmark of Alzheimer's disease (AD) and is believed to be causally involved in a neurodegenerative cascade. In patients with AD, reduced levels of serum Brain Derived Neurotrophic Factor (BDNF) and cortical 5-HT(2A) receptor binding has recently...... been reported but it is unknown how these changes are related to beta-amyloid accumulation. In this study we examined in rats the effect of intrahippocampal injections of aggregated Abeta(1-42) (1 microg/microl) on serum and brain BDNF or 5-HT(2A) receptor levels. A social recognition test paradigm...... was used to monitor Abeta(1-42) induced memory impairment. Memory impairment was seen 22 days after injection of Abeta(1-42) in the experimental group and until termination of the experiments. In the Abeta(1-42) injected animals we saw an abolished increase in serum BDNF levels that was accompanied...

  4. Food restriction and streptozotocin treatment decrease 5-HT1A and 5-HT2A receptor mediated behavioral effects in rats

    OpenAIRE

    Li, Jun-Xu; France, Charles P.

    2008-01-01

    Food restriction and hypoinsulinemia can affect the synthesis, turnover and receptor function of serotonin (5-HT) in brain. This study explored the effects of food restriction and streptozotocin treatment on behavioral effects related to 5-HT1A (8-OH-DPAT) and 5-HT2A (DOI) receptor activation. Lower lip retraction and flat body posture (8-OH-DPAT) and head twitching (DOI) were measured in rats during free feeding, food restriction, after treatment with streptozotocin, and finally after insuli...

  5. Hallucinogenic 5-HT2AR agonists LSD and DOI enhance dopamine D2R protomer recognition and signaling of D2-5-HT2A heteroreceptor complexes.

    Science.gov (United States)

    Borroto-Escuela, Dasiel O; Romero-Fernandez, Wilber; Narvaez, Manuel; Oflijan, Julia; Agnati, Luigi F; Fuxe, Kjell

    2014-01-01

    Dopamine D2LR-serotonin 5-HT2AR heteromers were demonstrated in HEK293 cells after cotransfection of the two receptors and shown to have bidirectional receptor-receptor interactions. In the current study the existence of D2L-5-HT2A heteroreceptor complexes was demonstrated also in discrete regions of the ventral and dorsal striatum with in situ proximity ligation assays (PLA). The hallucinogenic 5-HT2AR agonists LSD and DOI but not the standard 5-HT2AR agonist TCB2 and 5-HT significantly increased the density of D2like antagonist (3)H-raclopride binding sites and significantly reduced the pKiH values of the high affinity D2R agonist binding sites in (3)H-raclopride/DA competition experiments. Similar results were obtained in HEK293 cells and in ventral striatum. The effects of the hallucinogenic 5-HT2AR agonists on D2R density and affinity were blocked by the 5-HT2A antagonist ketanserin. In a forskolin-induced CRE-luciferase reporter gene assay using cotransfected but not D2R singly transfected HEK293 cells DOI and LSD but not TCB2 significantly enhanced the D2LR agonist quinpirole induced inhibition of CRE-luciferase activity. Haloperidol blocked the effects of both quinpirole alone and the enhancing actions of DOI and LSD while ketanserin only blocked the enhancing actions of DOI and LSD. The mechanism for the allosteric enhancement of the D2R protomer recognition and signalling observed is likely mediated by a biased agonist action of the hallucinogenic 5-HT2AR agonists at the orthosteric site of the 5-HT2AR protomer. This mechanism may contribute to the psychotic actions of LSD and DOI and the D2-5-HT2A heteroreceptor complex may thus be a target for the psychotic actions of hallunicogenic 5-HT2A agonists.

  6. Altered 5-HT2A Receptor Binding after Recovery from Bulimia-Type Anorexia Nervosa: Relationships to Harm Avoidance and Drive for Thinness

    OpenAIRE

    Bailer, Ursula F.; Price, Julie C.; Meltzer, Carolyn C.; Mathis, Chester A.; Frank, Guido K.; Weissfeld, Lisa; McConaha, Claire W; Henry, Shannan E; Brooks-Achenbach, Sarah; Barbarich, Nicole C; Kaye, Walter H.

    2004-01-01

    Several lines of evidence suggest that a disturbance of serotonin neuronal pathways may contribute to the pathogenesis of anorexia nervosa (AN) and bulimia nervosa (BN). This study applied positron emission tomography (PET) to investigate the brain serotonin 2A (5-HT2A) receptor, which could contribute to disturbances of appetite and behavior in AN and BN. To avoid the confounding effects of malnutrition, we studied 10 women recovered from bulimia-type AN (REC AN–BN, >1 year normal weight, re...

  7. Effects of the 5-HT2A agonist psilocybin on mismatch negativity generation and AX-continuous performance task: implications for the neuropharmacology of cognitive deficits in schizophrenia.

    Science.gov (United States)

    Umbricht, Daniel; Vollenweider, Franz X; Schmid, Liselotte; Grübel, Claudia; Skrabo, Anja; Huber, Theo; Koller, Rene

    2003-01-01

    Previously the NMDA (N-methyl-D-aspartate) receptor (NMDAR) antagonist ketamine was shown to disrupt generation of the auditory event-related potential (ERP) mismatch negativity (MMN) and the performance of an 'AX'-type continuous performance test (AX-CPT)--measures of auditory and visual context-dependent information processing--in a similar manner as observed in schizophrenia. This placebo-controlled study investigated effects of the 5-HT(2A) receptor agonist psilocybin on the same measures in 18 healthy volunteers. Psilocybin administration induced significant performance deficits in the AX-CPT, but failed to reduce MMN generation significantly. These results indirectly support evidence that deficient MMN generation in schizophrenia may be a relatively distinct manifestation of deficient NMDAR functioning. In contrast, secondary pharmacological effects shared by NMDAR antagonists and the 5-HT(2A) agonist (ie disruption of glutamatergic neurotransmission) may be the mechanism underlying impairments in AX-CPT performance observed during both psilocybin and ketamine administration. Comparable deficits in schizophrenia may result from independent dysfunctions of 5-HT(2A) and NMDAR-related neurotransmission.

  8. Discovery of a new class of potential multifunctional atypical antipsychotic agents targeting dopamine D3 and serotonin 5-HT1A and 5-HT2A receptors: design, synthesis, and effects on behavior

    DEFF Research Database (Denmark)

    Butini, Stefania; Gemma, Sandra; Campiani, Giuseppe;

    2009-01-01

    Dopamine D(3) antagonism combined with serotonin 5-HT(1A) and 5-HT(2A) receptor occupancy may represent a novel paradigm for developing innovative antipsychotics. The unique pharmacological features of 5i are a high affinity for dopamine D(3), serotonin 5-HT(1A) and 5-HT(2A) receptors, together w...

  9. A Model of Post-Infection Fatigue Is Associated with Increased TNF and 5-HT2A Receptor Expression in Mice.

    Science.gov (United States)

    Couch, Yvonne; Xie, Qin; Lundberg, Louise; Sharp, Trevor; Anthony, Daniel C

    2015-01-01

    It is well documented that serotonin (5-HT) plays an important role in psychiatric illness. For example, myalgic encephalomyelitis (ME/CFS), which is often provoked by infection, is a disabling illness with an unknown aetiology and diagnosis is based on symptom-specific criteria. However, 5-HT2A receptor expression and peripheral cytokines are known to be upregulated in ME. We sought to examine the relationship between the 5-HT system and cytokine expression following systemic bacterial endotoxin challenge (LPS, 0.5 mg/kg i.p.), at a time when the acute sickness behaviours have largely resolved. At 24 hours post-injection mice exhibit no overt changes in locomotor behaviour, but do show increased immobility in a forced swim test, as well as decreased sucrose preference and reduced marble burying activity, indicating a depressive-like state. While peripheral IDO activity was increased after LPS challenge, central activity levels remained stable and there was no change in total brain 5-HT levels or 5-HIAA/5-HT. However, within the brain, levels of TNF and 5-HT2A receptor mRNA within various regions increased significantly. This increase in receptor expression is reflected by an increase in the functional response of the 5-HT2A receptor to agonist, DOI. These data suggest that regulation of fatigue and depressive-like moods after episodes of systemic inflammation may be regulated by changes in 5-HT receptor expression, rather than by levels of enzyme activity or cytokine expression in the CNS. PMID:26147001

  10. Role for serotonin2A (5-HT2A) and 2C (5-HT2C) receptors in experimental absence seizures.

    Science.gov (United States)

    Venzi, Marcello; David, François; Bellet, Joachim; Cavaccini, Anna; Bombardi, Cristiano; Crunelli, Vincenzo; Di Giovanni, Giuseppe

    2016-09-01

    Absence seizures (ASs) are the hallmark of childhood/juvenile absence epilepsy. Monotherapy with first-line anti-absence drugs only controls ASs in 50% of patients, indicating the need for novel therapeutic targets. Since serotonin family-2 receptors (5-HT2Rs) are known to modulate neuronal activity in the cortico-thalamo-cortical loop, the main network involved in AS generation, we investigated the effect of selective 5-HT2AR and 5-HT2CR ligands on ASs in the Genetic Absence Epilepsy Rats from Strasbourg (GAERS), a well established polygenic rat model of these non-convulsive seizures. GAERS rats were implanted with fronto-parietal EEG electrodes under general anesthesia, and their ASs were later recorded under freely moving conditions before and after intraperitoneal administration of various 5-HT2AR and 5-HT2CR ligands. The 5-HT2A agonist TCB-2 dose-dependently decreased the total time spent in ASs, an effect that was blocked by the selective 5-HT2A antagonist MDL11,939. Both MDL11,939 and another selective 5-HT2A antagonist (M100,907) increased the length of individual seizures when injected alone. The 5-HT2C agonists lorcaserin and CP-809,101 dose-dependently suppressed ASs, an effect blocked by the selective 5-HT2C antagonist SB 242984. In summary, 5-HT2ARs and 5-HT2CRs negatively control the expression of experimental ASs, indicating that selective agonists at these 5-HT2R subtypes might be potential novel anti-absence drugs. PMID:27085605

  11. A Model of Post-Infection Fatigue Is Associated with Increased TNF and 5-HT2A Receptor Expression in Mice.

    Directory of Open Access Journals (Sweden)

    Yvonne Couch

    Full Text Available It is well documented that serotonin (5-HT plays an important role in psychiatric illness. For example, myalgic encephalomyelitis (ME/CFS, which is often provoked by infection, is a disabling illness with an unknown aetiology and diagnosis is based on symptom-specific criteria. However, 5-HT2A receptor expression and peripheral cytokines are known to be upregulated in ME. We sought to examine the relationship between the 5-HT system and cytokine expression following systemic bacterial endotoxin challenge (LPS, 0.5 mg/kg i.p., at a time when the acute sickness behaviours have largely resolved. At 24 hours post-injection mice exhibit no overt changes in locomotor behaviour, but do show increased immobility in a forced swim test, as well as decreased sucrose preference and reduced marble burying activity, indicating a depressive-like state. While peripheral IDO activity was increased after LPS challenge, central activity levels remained stable and there was no change in total brain 5-HT levels or 5-HIAA/5-HT. However, within the brain, levels of TNF and 5-HT2A receptor mRNA within various regions increased significantly. This increase in receptor expression is reflected by an increase in the functional response of the 5-HT2A receptor to agonist, DOI. These data suggest that regulation of fatigue and depressive-like moods after episodes of systemic inflammation may be regulated by changes in 5-HT receptor expression, rather than by levels of enzyme activity or cytokine expression in the CNS.

  12. A PET [18F]altanserin study of 5-HT2A receptor binding in the human brain and responses to painful heat stimulation

    DEFF Research Database (Denmark)

    Kupers, Ronny Clement Florent; Frokjaer, Vibe G; Naert, Arne;

    2009-01-01

    stimulation in a group of young healthy volunteers. Twenty-one healthy subjects underwent PET scanning with the 5-HT(2A) antagonist, [(18)F]altanserin. In addition, participants underwent a battery of pain tests using noxious heat stimulation to assess pain threshold, pain tolerance and response to short....... The correlation between [(18)F]altanserin binding in prefrontal cortex and tonic pain suggests a possible role of this brain region in the modulation and/or cognitive-evaluative appreciation of pain....

  13. The 5-HT2A receptor and serotonin transporter in Asperger’s Disorder: a PET study with [11C]MDL 100907 and [11C]DASB

    OpenAIRE

    Girgis, Ragy R.; Slifstein, Mark; Xu, Xiaoyan; Frankle, W. Gordon; Anagnostou, Evdokia; Wasserman, Stacey; Pepa, Lauren; Kolevzon, Alexander; Abi-Dargham, Anissa; Laruelle, Marc; Hollander, Eric

    2011-01-01

    Evidence from biochemical, imaging, and treatment studies suggest abnormalities of the serotonin system in autism spectrum disorders, in particular in frontolimbic areas of the brain. We used the radiotracers [11C]MDL 100907 and [11C]DASB to characterize the 5-HT2A receptor and serotonin transporter in Asperger’s Disorder. 17 individuals with Asperger’s Disorder (age = 34.3 ± 11.1 yr) and 17 healthy controls (age = 33.0 ± 9.6 yr) were scanned with [11C]MDL 100907. Of the 17 patients, eight (a...

  14. Horse chestnut extract contracts bovine vessels and affects human platelet aggregation through 5-HT(2A) receptors: an in vitro study.

    Science.gov (United States)

    Felixsson, Emma; Persson, Ingrid A-L; Eriksson, Andreas C; Persson, Karin

    2010-09-01

    Extract from seeds and bark of horse chestnut (Aesculus hippocastanum L) is used as an herbal medicine against chronic venous insufficiency. The effect and mechanism of action on veins, arteries, and platelets are not fully understood. The aim of this study was to investigate the effects and mechanisms of action of horse chestnut on the contraction of bovine mesenteric veins and arteries, and human platelet aggregation. Contraction studies showed that horse chestnut extract dose-dependently contracted both veins and arteries, with the veins being the most sensitive. Contraction of both veins and arteries were significantly inhibited by the 5-HT(2A) receptor antagonist ketanserin. No effect on contraction was seen with the cyclooxygenase inhibitor indomethacin, the alpha(1) receptor antagonist prazosin or the angiotensin AT(1) receptor antagonist saralasin neither in veins nor arteries. ADP-induced human platelet aggregation was significantly reduced by horse chestnut. A further reduction was seen with the extract in the presence of ketanserin. In conclusion, horse chestnut contraction of both veins and arteries is, at least partly, mediated through 5-HT(2A) receptors. Human platelet aggregation is reduced by horse chestnut. The clinical importance of these findings concerning clinical use, possible adverse effects, and drug interactions remains to be investigated. PMID:20148408

  15. Test-retest variability of high resolution positron emission tomography (PET) imaging of cortical serotonin (5HT2A) receptors in older, healthy adults

    International Nuclear Information System (INIS)

    Position emission tomography (PET) imaging using [18F]-setoperone to quantify cortical 5-HT2A receptors has the potential to inform pharmacological treatments for geriatric depression and dementia. Prior reports indicate a significant normal aging effect on serotonin 5HT2A receptor (5HT2AR) binding potential. The purpose of this study was to assess the test-retest variability of [18F]-setoperone PET with a high resolution scanner (HRRT) for measuring 5HT2AR availability in subjects greater than 60 years old. Methods: Six healthy subjects (age range = 65–78 years) completed two [18F]-setoperone PET scans on two separate occasions 5–16 weeks apart. The average difference in the binding potential (BPND) as measured on the two occasions in the frontal and temporal cortical regions ranged between 2 and 12%, with the lowest intraclass correlation coefficient in anterior cingulate regions. We conclude that the test-retest variability of [18F]-setoperone PET in elderly subjects is comparable to that of [18F]-setoperone and other 5HT2AR radiotracers in younger subject samples

  16. The 5-HT(2A) receptor and serotonin transporter in Asperger's disorder: A PET study with [¹¹C]MDL 100907 and [¹¹C]DASB.

    Science.gov (United States)

    Girgis, Ragy R; Slifstein, Mark; Xu, Xiaoyan; Frankle, W Gordon; Anagnostou, Evdokia; Wasserman, Stacey; Pepa, Lauren; Kolevzon, Alexander; Abi-Dargham, Anissa; Laruelle, Marc; Hollander, Eric

    2011-12-30

    Evidence from biochemical, imaging, and treatment studies suggest abnormalities of the serotonin system in autism spectrum disorders, in particular in frontolimbic areas of the brain. We used the radiotracers [(11)C]MDL 100907 and [(11)C]DASB to characterize the 5-HT(2A) receptor and serotonin transporter in Asperger's Disorder. Seventeen individuals with Asperger's Disorder (age=34.3 ± 11.1 years) and 17 healthy controls (age=33.0 ± 9.6 years) were scanned with [(11)C]MDL 100907. Of the 17 patients, eight (age=29.7 ± 7.0 years) were also scanned with [¹¹C]DASB, as were eight healthy controls (age=28.7 ± 7.0 years). Patients with Asperger's Disorder and healthy control subjects were matched for age, gender, and ethnicity, and all had normal intelligence. Metabolite-corrected arterial plasma inputs were collected and data analyzed by two-tissue compartment modeling. The primary outcome measure was regional binding potential BP(ND). Neither regional [¹¹C]MDL 100907 BP(ND) nor [¹¹C]DASB BP(ND) was statistically different between the Asperger's and healthy subjects. This study failed to find significant alterations in binding parameters of 5-HT(2A) receptors and serotonin transporters in adult subjects with Asperger's disorder. PMID:22079057

  17. Synthesis and in vivo evaluation of [O-methyl-11C](2R,4R)-4-hydroxy-2-[2-[2-[2-(3-methoxy)phenyl]ethyl]phenoxy] ethyl-1-methylpyrrolidine as a 5-HT2A receptor PET ligand

    International Nuclear Information System (INIS)

    The serotonin2A (5-HT2A) receptor is implicated in the pathophysiology of schizophrenia and mood disorders, and in vivo studies of this receptor would be of value in studying the pathophysiology of these disorders and in measuring the relationship of clinical response to receptor occupancy for 5-HT2A antagonists such as atypical antipsychotics. Therefore, (2R,4R)-4-hydroxy-2-[2-[2-[2-(3-methoxy)-phenyl]ethyl] phenoxy]ethyl-1-methylpyrrolidine (MPM) (13), a selective and high-affinity (K i=0.79 nM) 5HT2A antagonist, has been radiolabeled with carbon-11 by O-methylation of the corresponding desmethyl analogue (2R,4R)-4-hydroxy-2-[2-[2-[2-(3-hydroxy)phenyl]ethyl]phenoxy] ethyl-1-methylpyrrolidine (12) with [11C]methyltriflate in order to determine the suitability of [11C]MPM to quantify 5-HT2A in living brain using PET. Desmethyl-MPM 12 and standard MPM were prepared, starting from 3-hydroxymethylphenol (2), in excellent yield. The yield obtained for radiolabeling was 40±5% (EOB), and the total synthesis time was 30 min at EOS. PET studies with [11C]MPM in baboon showed a distribution in the brain consistent with the known distribution of 5-HT2A receptors. The time-activity curves for the high-binding regions peaked at ∼45 min after injection. Blocking studies with M100907 demonstrated not only 38-57% blocking of tracer binding in brain regions known to have 5-HT2A receptors but also 38% blocking in cerebellum, which has a low 5-HT2A receptor concentration. Although [11C]MPM exhibits appropriate kinetics in baboon for imaging 5-HT2A receptors, its specific binding in cerebellum and higher proportion of nonspecific binding limit its usefulness for the in vivo quantification of 5-HT2A receptors with PET

  18. Effects of imipramine and bupropion on the duration of immobility of ACTH-treated rats in the forced swim test: involvement of the expression of 5-HT2A receptor mRNA.

    Science.gov (United States)

    Kitamura, Yoshihisa; Fujitani, Yoshika; Kitagawa, Kouhei; Miyazaki, Toshiaki; Sagara, Hidenori; Kawasaki, Hiromu; Shibata, Kazuhiko; Sendo, Toshiaki; Gomita, Yutaka

    2008-02-01

    We examined the effect of chronic administration of imipramine and bupropion, monoamine reuptake inhibitors, on the duration of immobility in the forced swim test and serotonin (5-HT)(2A) receptor function in the form of 5-HT(2A) receptor mRNA levels in rats chronically treated with adrenocorticotropic hormone (ACTH). The immobility-decreasing effect of bupropion without imipramine did not influence the chronic ACTH treatment. The effect on the expression of 5-HT(2A) receptor mRNA of chronic ACTH treatment was decreased by bupropion, but not imipramine. These results suggest that bupropion has the effect of reducing immobility time in the forced swim test in the tricyclic antidepressant-resistant depressive model induced by chronic ACTH treatment in rats, and that decreased 5-HT(2A) receptor mRNA levels may be involved in this phenomenon.

  19. The effects of the preferential 5-HT2A agonist psilocybin on prepulse inhibition of startle in healthy human volunteers depend on interstimulus interval.

    Science.gov (United States)

    Vollenweider, Franz X; Csomor, Philipp A; Knappe, Bernhard; Geyer, Mark A; Quednow, Boris B

    2007-09-01

    Schizophrenia patients exhibit impairments in prepulse inhibition (PPI) of the startle response. Hallucinogenic 5-HT(2A) receptor agonists are used for animal models of schizophrenia because they mimic some symptoms of schizophrenia in humans and induce PPI deficits in animals. Nevertheless, one report indicates that the 5-HT(2A) receptor agonist psilocybin increases PPI in healthy humans. Hence, we investigated these inconsistent results by assessing the dose-dependent effects of psilocybin on PPI in healthy humans. Sixteen subjects each received placebo or 115, 215, and 315 microg/kg of psilocybin at 4-week intervals in a randomized and counterbalanced order. PPI at 30-, 60-, 120-, 240-, and 2000-ms interstimulus intervals (ISIs) was measured 90 and 165 min after drug intake, coinciding with the peak and post-peak effects of psilocybin. The effects of psilocybin on psychopathological core dimensions and sustained attention were assessed by the Altered States of Consciousness Rating Scale (5D-ASC) and the Frankfurt Attention Inventory (FAIR). Psilocybin dose-dependently reduced PPI at short (30 ms), had no effect at medium (60 ms), and increased PPI at long (120-2000 ms) ISIs, without affecting startle reactivity or habituation. Psilocybin dose-dependently impaired sustained attention and increased all 5D-ASC scores with exception of Auditory Alterations. Moreover, psilocybin-induced impairments in sustained attention performance were positively correlated with reduced PPI at the 30 ms ISI and not with the concomitant increases in PPI observed at long ISIs. These results confirm the psilocybin-induced increase in PPI at long ISIs and reveal that psilocybin also produces a decrease in PPI at short ISIs that is correlated with impaired attention and consistent with deficient PPI in schizophrenia.

  20. Augmentative effect of tetrandrine on pentobarbital hypnosis mediated by 5-HT1A and 5-HT2A/2C receptors in mice%5-HT1A和5-HT2A/2C受体在粉防己碱增强戊巴比妥钠睡眠中的介导作用

    Institute of Scientific and Technical Information of China (English)

    杜楠; 王黎恩; 师晓荣; 崔翔宇; 崔素颖; 张帆; 张永鹤

    2008-01-01

    前期研究表明粉防己碱增强戊巴比妥钠诱导的催眠作用与5-HT系统相关.本研究采用戊巴比妥钠(45 mg/kg,协)诱导的小鼠翻正反射消失和恢复实验方法,对粉防己碱与不同5-HT受体在增强戊巴比妥钠诱导睡眠中的相互作用进行了探讨.结果表明粉防己碱分别与选择性5-HT1A受体拮抗剂p-MPPI(1 mg/kg,i.p.),选择性5-HT2A/2C受体拮抗剂ketanserin(1.5mg/kg,i.p.)合用可以显著增强戊巴比妥钠诱导的催眠作用.选择性5-HT1A受体激动剂8-OH-DPAT(0.1 mg/kg,s.c.)或5-HT2A/2C受体激动剂DOI(0.2 mg/kg.i.p.)能够显著减少戊巴比妥钠诱导的小鼠睡眠时间,而粉防己碱(60 mg/kg,i.p.)可以显著拮抗这种睡眠抑制作用.此结果提示,粉防己碱增强戊巴比妥钠诱导的催眠作用可能与5-HT1A受体和5-HT2A/2C受体有关.%It has been reported that augmentative effect of tetrandrine on pentobarbital hypnosis in mice may be related to sero-tonergic system. The present study was undertaken to investigate the interaction of tetrandrine and different 5-HT receptors on pentobarbital-induced sleep by using the loss-of-righting reflex method. The results showed that augmentative effect of tetrandrine on pentobarbital hypnosis in mice were potentiated by the p-MPPI (5-HT1A receptor antagonist) (1 mg/kg, i.p.) and ketanserin (5-HT2A/2C receptor antagonist) (1.5 mg/kg, i.p.), respectively. Pretreatment with either 8-OH-DPAT (5-HT1A receptor agonist)(0.1 mg/kg, s.c.) or DOI (5-HT2A/2C receptor agonist) (0.2 mg/kg, i.p.) significantly decreased pentobarbital-induced sleep time,and tetrandrine (60 mg/kg, i.g.) significantly reversed this effect. These results suggest that both the 5-HTtA and 5-HT2A/2C subfamily may be involved in the potentiating mechanism of tetrandrine's effects on pentobarbital hypnosis.

  1. Potentiation of 5-methoxy-N,N-dimethyltryptamine-induced hyperthermia by harmaline and the involvement of activation of 5-HT1A and 5-HT2A receptors.

    Science.gov (United States)

    Jiang, Xi-Ling; Shen, Hong-Wu; Yu, Ai-Ming

    2015-02-01

    5-Methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and harmaline are serotonin (5-HT) analogs often abused together, which alters thermoregulation that may indicate the severity of serotonin toxicity. Our recent studies have revealed that co-administration of monoamine oxidase inhibitor harmaline leads to greater and prolonged exposure to 5-HT agonist 5-MeO-DMT that might be influenced by cytochrome P450 2D6 (CYP2D6) status. This study was to define the effects of harmaline and 5-MeO-DMT on thermoregulation in wild-type and CYP2D6-humanized (Tg-CYP2D6) mice, as well as the involvement of 5-HT receptors. Animal core body temperatures were monitored noninvasively in the home cages after implantation of telemetry transmitters and administration of drugs. Harmaline (5 and 15 mg/kg, i.p.) alone was shown to induce hypothermia that was significantly affected by CYP2D6 status. In contrast, higher doses of 5-MeO-DMT (10 and 20 mg/kg) alone caused hyperthermia. Co-administration of harmaline (2, 5 or 15 mg/kg) remarkably potentiated the hyperthermia elicited by 5-MeO-DMT (2 or 10 mg/kg), which might be influenced by CYP2D6 status at certain dose combination. Interestingly, harmaline-induced hypothermia was only attenuated by 5-HT1A receptor antagonist WAY-100635, whereas 5-MeO-DMT- and harmaline-5-MeO-DMT-induced hyperthermia could be suppressed by either WAY-100635 or 5-HT2A receptor antagonists (MDL-100907 and ketanserin). Moreover, stress-induced hyperthermia under home cage conditions was not affected by WAY-100635 but surprisingly attenuated by MDL-100907 and ketanserin. Our results indicate that co-administration of monoamine oxidase inhibitor largely potentiates 5-MeO-DMT-induced hyperthermia that involves the activation of both 5-HT1A and 5-HT2A receptors. These findings shall provide insights into development of anxiolytic drugs and new strategies to relieve the lethal hyperthermia in serotonin toxicity. PMID:25446678

  2. Serotonin 5-HT2A receptor binding in platelets from healthy subjects as studied by [3H]-lysergic acid diethylamide ([3H]-LSD): intra- and interindividual variability.

    Science.gov (United States)

    Spigset, O; Mjörndal, T

    1997-04-01

    In studies on platelet 5-HT2A receptor binding in patients with neuropsychiatric disorders, there has been a marked variability and a considerable overlap of values between patients and controls. The causes of the large variability in 5-HT2A receptor parameters is still unsettled. In the present study, we have quantified the intra- and interindividual variability of platelet 5-HT2A receptor binding in 112 healthy subjects and explored factors that may influence 5-HT2A receptor binding, using [3H]-lysergic acid diethylamide as radioligand. Age, gender, blood pressure, and metabolic capacity of the liver enzymes CYP2D6 and CYP2C19 did not influence Bmax and Kd values. Body weight and body mass index (BMI) showed a negative correlation with Kd (p = .04 and .03, respectively), but not with Bmax. Bmax was significantly lower in the light half of the year than in the dark half of the year (p = .001), and Kd was significantly lower in the fall than in the summer and winter (p < .001). In females, there was a significant increase in Bmax from week 1 to week 2 of the menstrual cycle (p = .03). Females taking contraceptive pills had significantly higher Kd than drug-free females in weeks 1 and 4 of the menstrual cycle (p = .04). This study shows that a number of factors should be taken into account when using platelet 5-HT2A receptor binding in studies of neuropsychiatric disorders.

  3. Holographic Quantitative Structure-Activity Relationships of Tryptamine Derivatives at NMDA, 5HT1A and 5HT2A Receptors

    Directory of Open Access Journals (Sweden)

    Peter Wolschann

    2013-07-01

    Full Text Available Tryptamine derivatives (Ts were found to inhibit the binding of [3H]MK-801, [3H]ketanserin and [3H]8-OH-DPAT to rat brain membranes. [3H]MK-801 labels the NMDA (N-methyl-D-aspartate receptor, a ionotropic glutamate receptor which controls synaptic plasticity and memory function in the brain, whereas [3H]ketanserin and [3H]8-OH-DPAT label 5HT2A and 5HT1A receptors, respectively. The inhibitory potencies of 64 Ts (as given by IC50 values were correlated with their structural properties by using the Holographic QSAR procedure (HQSAR. This method uses structural fragments and connectivities as descriptors which were encoded in a hologram thus avoiding the usual problems with conformation and alignment of the structures. Four correlation equations with high predictive ability and appropriate statistical test values could be established. The results are visualized by generation of maps reflecting the contribution of individual structural parts to the biological activities.

  4. QSAR–CoMSIA applied to antipsychotic drugs with their dopamine D2 and serotonine 5HT2A membrane receptors

    Directory of Open Access Journals (Sweden)

    SPERANTA AVRAM

    2011-02-01

    Full Text Available Antipsychotic drugs are psychiatric medication primarily used to manage psychosis (e.g., delusions or hallucinations, particularly in schizophrenia and bipolar disorder. First and second generations of antipshychotics tend to block receptors in the brain's dopamine pathways, but antipsychotic drugs encompass a wide range of receptor targets. The inhibition constant, Ki, at the level of membrane receptors is a major determinant of their pharmacokinetic behavior and, consequently, it can affect their antipsychotic activity. Here, predicted inhibition constants, Ki for 71 antipsychotics, already approved for clinical treatment, as well as representative new chemical structures which exhibit antipsychotic activity, were evaluated using 3D-QSAR–CoMSIA models. Significant values of the cross-validated correlation q2 (higher than 0.70 and the fitted correlation r2 (higher than 0.80 revealed that these models have reasonable power to predict the biological affinity of the 15 new risperidone and 12 new olanzapine derivatives in interactions with dopamine D2 and serotonin 5HT2A receptors; these compounds are suggested for further studies.

  5. Examination of the hippocampal contribution to serotonin 5-HT2A receptor-mediated facilitation of object memory in C57BL/6J mice.

    Science.gov (United States)

    Zhang, Gongliang; Cinalli, David; Cohen, Sarah J; Knapp, Kristina D; Rios, Lisa M; Martínez-Hernández, José; Luján, Rafael; Stackman, Robert W

    2016-10-01

    The rodent hippocampus supports non-spatial object memory. Serotonin 5-HT2A receptors (5-HT2AR) are widely expressed throughout the hippocampus. We previously demonstrated that the activation of 5-HT2ARs enhanced the strength of object memory assessed 24 h after a limited (i.e., weak memory) training procedure. Here, we examined the subcellular distribution of 5-HT2ARs in the hippocampal CA1 region and underlying mechanisms of 5-HT2AR-mediated object memory consolidation. Analyses with immuno-electron microscopy revealed the presence of 5-HT2ARs on the dendritic spines and shafts of hippocampal CA1 neurons, and presynaptic terminals in the CA1 region. In an object recognition memory procedure that places higher demand on the hippocampus, only post-training systemic or intrahippocampal administration of the 5-HT2AR agonist TCB-2 enhanced object memory. Object memory enhancement by TCB-2 was blocked by the 5-HT2AR antagonist, MDL 11,937. The memory-enhancing dose of systemic TCB-2 increased extracellular glutamate levels in hippocampal dialysate samples, and increased the mean in vivo firing rate of hippocampal CA1 neurons. In summary, these data indicate a pre- and post-synaptic distribution of 5-HT2ARs, and activation of 5-HT2ARs selectively enhanced the consolidation of object memory, without affecting encoding or retrieval. The 5-HT2AR-mediated facilitation of hippocampal memory may be associated with an increase in hippocampal neuronal firing and glutamate efflux during a post-training time window in which recently encoded memories undergo consolidation. PMID:27114257

  6. Elevated expression of serotonin 5-HT2A receptors in the rat ventral tegmental area enhances vulnerability to the behavioral effects of cocaine

    Directory of Open Access Journals (Sweden)

    David V. Herin

    2013-02-01

    Full Text Available The dopamine mesocorticoaccumbens pathway which originates in the ventral tegmental area (VTA and projects to the nucleus accumbens and prefrontal cortex is a circuit important in mediating the actions of psychostimulants. The function of this circuit is modulated by the actions of serotonin (5-HT at 5-HT2A receptors (5-HT2AR localized to the VTA. In the present study, we tested the hypothesis that virally-mediated overexpression of 5-HT2AR in the VTA would increase cocaine-evoked locomotor activity in the absence of alterations in basal locomotor activity. A plasmid containing the gene for the 5-HT2AR linked to a synthetic marker peptide (Flag was created and the construct was packaged in an adeno-associated virus vector (rAAV-5-HT2AR-Flag. This viral vector (2 µl; 109-10 transducing units/ml was unilaterally infused into the VTA of male rats, while control animals received an intra-VTA infusion of Ringer’s solution. Virus-pretreated rats exhibited normal spontaneous locomotor activity measured in a modified open-field apparatus at 7, 14, and 21 days following infusion. After an injection of cocaine (15 mg/kg, ip, both horizontal hyperactivity and rearing were significantly enhanced in virus-treated rats (p<0.05. Immunohistochemical analysis confirmed expression of Flag and overexpression of the 5-HT2AR protein. These data indicate that the vulnerability of adult male rats to hyperactivity induced by cocaine is enhanced following increased levels of expression of the 5-HT2AR in the VTA and suggest that the 5-HT2AR receptor in the VTA plays a role in regulation of responsiveness to cocaine.

  7. Antidepressant-like activity of Tagetes lucida Cav. is mediated by 5-HT(1A) and 5-HT(2A) receptors.

    Science.gov (United States)

    Bonilla-Jaime, H; Guadarrama-Cruz, G; Alarcon-Aguilar, F J; Limón-Morales, O; Vazquez-Palacios, G

    2015-10-01

    It has been demonstrated that the aqueous extract of Tagetes lucida Cav. shows an antidepressant-like effect on the forced swimming test (FST) in rats. The aim of this study was to analyze the participation of the serotoninergic system in the antidepressant-like effect of the aqueous extract of T. lucida. Different doses of the extract of T. lucida were administered at 72, 48, 24, 18 and 1 h before FST. The animals were pretreated with a 5-HT1A receptor antagonist (WAY-100635, 0.5 mg/kg), a 5-HT2A receptor antagonist (ketanserin, 5 mg/kg), a β-noradrenergic receptor antagonist (propranolol, 200 mg/kg), and with a α2-noradrenergic receptor antagonist (yohimbine, 1 mg/kg) alone or combined with the extract and pretreated with a serotonin synthesis inhibitor (PCPA) before treatment with 8-OH-DPAT + the extract of T. lucida. In addition, suboptimal doses of the 5-HT1A agonist (8-OH-DPAT) + non-effective dose of extract was analyzed in the FST. To determine the presence of flavonoids, the aqueous extract of T. lucida (20 µl, 4 mg/ml) was injected in HPLC; however, a quercetin concentration of 7.72 mg/g of extract weight was detected. A suboptimal dose of 8-OH-DPAT + extract of T. lucida decreased immobility and increased swimming and climbing. An antidepressant-like effect with the aqueous extract of T. lucida at doses of 100 and 200 mg/kg was observed on the FST with decreased immobility behavior and increased swimming; however, this effect was blocked by WAY-100635, ketanserin and PCPA but not by yohimbine and propranolol, suggesting that the extract of T. lucida could be modulating the release/reuptake of serotonin.

  8. Cognitive Impairment Induced by Delta9-tetrahydrocannabinol Occurs through Heteromers between Cannabinoid CB1 and Serotonin 5-HT2A Receptors.

    Directory of Open Access Journals (Sweden)

    Xavier Viñals

    2015-07-01

    Full Text Available Activation of cannabinoid CB1 receptors (CB1R by delta9-tetrahydrocannabinol (THC produces a variety of negative effects with major consequences in cannabis users that constitute important drawbacks for the use of cannabinoids as therapeutic agents. For this reason, there is a tremendous medical interest in harnessing the beneficial effects of THC. Behavioral studies carried out in mice lacking 5-HT2A receptors (5-HT2AR revealed a remarkable 5-HT2AR-dependent dissociation in the beneficial antinociceptive effects of THC and its detrimental amnesic properties. We found that specific effects of THC such as memory deficits, anxiolytic-like effects, and social interaction are under the control of 5-HT2AR, but its acute hypolocomotor, hypothermic, anxiogenic, and antinociceptive effects are not. In biochemical studies, we show that CB1R and 5-HT2AR form heteromers that are expressed and functionally active in specific brain regions involved in memory impairment. Remarkably, our functional data shows that costimulation of both receptors by agonists reduces cell signaling, antagonist binding to one receptor blocks signaling of the interacting receptor, and heteromer formation leads to a switch in G-protein coupling for 5-HT2AR from Gq to Gi proteins. Synthetic peptides with the sequence of transmembrane helices 5 and 6 of CB1R, fused to a cell-penetrating peptide, were able to disrupt receptor heteromerization in vivo, leading to a selective abrogation of memory impairments caused by exposure to THC. These data reveal a novel molecular mechanism for the functional interaction between CB1R and 5-HT2AR mediating cognitive impairment. CB1R-5-HT2AR heteromers are thus good targets to dissociate the cognitive deficits induced by THC from its beneficial antinociceptive properties.

  9. Equilibrium modeling of 5-ht2a receptors with [18f]deuteroaltanserin and PET: feasibility of a constant infusion paradigm

    International Nuclear Information System (INIS)

    [18F]Altanserin has emerged as a promising positron emission tomography (PET) ligand for serotonin-2A (5-HT2A) receptors. The deuterium substitution of both of the 2'-hydrogens of altanserin ([18F]deuteroaltanserin) yields a metabolically more stable radiotracer with higher ratios of parent tracer to radiometabolites and increased specific brain uptake than [18F]altanserin. The slower metabolism of the deuterated analog might preclude the possibility of achieving stable plasma and brain activities with a bolus plus constant infusion within a reasonable time frame for an 18F-labeled tracer (T1/2 110 min). Thus, the purpose of this study was to test the feasibility in human subjects of a constant infusion paradigm for equilibrium modeling of [18F]deuteroaltanserin with PET. Seven healthy male subjects were injected with [18F]deuteroaltanserin as a bolus plus constant infusion lasting 10 h postinjection. PET acquisitions and venous blood sampling were performed throughout the infusion period. Linear regression analysis revealed that time-activity curves for both specific brain uptake and plasma [18F]deuteroaltanserin concentration stabilized after about 5 h. This permitted equilibrium modeling and estimation of V'3 (ratio of specific uptake to total plasma parent concentration) and the binding potential V3 (ratio of specific uptake to free plasma parent concentration). Cortical/cerebellar ratios were increased by 26% relative to those we previously observed with [18F]altanserin using similar methodology in a somewhat older subject sample. These results demonstrate feasibility of equilibrium imaging with [18F]deuteroaltanserin and suggest that it may be superior to [18F]altanserin as a PET radioligand

  10. Modulating the rate and rhythmicity of perceptual rivalry alternations with the mixed 5-HT2A and 5-HT1A agonist psilocybin.

    Science.gov (United States)

    Carter, Olivia L; Pettigrew, John D; Hasler, Felix; Wallis, Guy M; Liu, Guang B; Hell, Daniel; Vollenweider, Franz X

    2005-06-01

    Binocular rivalry occurs when different images are presented simultaneously to corresponding points within the left and right eyes. Under these conditions, the observer's perception will alternate between the two perceptual alternatives. Motivated by the reported link between the rate of perceptual alternations, symptoms of psychosis and an incidental observation that the rhythmicity of perceptual alternations during binocular rivalry was greatly increased 10 h after the consumption of LSD, this study aimed to investigate the pharmacology underlying binocular rivalry and to explore the connection between the timing of perceptual switching and psychosis. Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine, PY) was chosen for the study because, like LSD, it is known to act as an agonist at serotonin (5-HT)1A and 5-HT2A receptors and to produce an altered state sometimes marked by psychosis-like symptoms. A total of 12 healthy human volunteers were tested under placebo, low-dose (115 microg/kg) and high-dose (250 microg/kg) PY conditions. In line with predictions, under both low- and high-dose conditions, the results show that at 90 min postadministration (the peak of drug action), rate and rhythmicity of perceptual alternations were significantly reduced from placebo levels. Following the 90 min testing period, the perceptual switch rate successively increased, with some individuals showing increases well beyond pretest levels at the final testing, 360 min postadministration. However, as some subjects had still not returned to pretest levels by this time, the mean phase duration at 360 min was not found to differ significantly from placebo. Reflecting the drug-induced changes in rivalry phase durations, subjects showed clear changes in psychological state as indexed by the 5D-ASC (altered states of consciousness) rating scales. This study suggests the involvement of serotonergic pathways in binocular rivalry and supports the previously proposed role of a brainstem

  11. Estimates of regional cerebral blood flow and 5-HT2A receptor density in impulsive, aggressive dogs with 99mTc-ECD and 123I-5-I-R91150

    International Nuclear Information System (INIS)

    Impulsive aggression in dogs has an important impact on human public health. Better insight into the pathophysiology of this phenomenon could lead to more adequate diagnosis and treatment. Indirect in vivo research on peripheral body fluids and post-mortem studies in impulsive animals and humans indicate a deficient serotonergic system in general and disturbances in the serotonin-2A (5-HT2A) receptor in particular. In this study, brain perfusion and the 5-HT2A receptors were examined in impulsive, aggressive dogs, in comparison with a group of normally behaving animals. In order to decide which dogs to include in this study, owners were asked to describe the general behaviour of the dogs, the circumstances in which aggression occurred and their conduct during aggressive acts. Finally, 19 dogs were retained for this study, showing, according to different behavioural specialists, disinhibited dominance aggression. Functional imaging studies were performed on all these dogs. Single-photon emission tomography (SPET) was used to measure regional brain perfusion using technetium-99m labelled ethyl cysteinate dimer (ECD). The 5-HT2A receptor binding properties were investigated using the selective radioligand iodine-123 labelled 5-I-R91150. A significant increase in uptake of the 5-HT2A radioligand was noted in all cortical areas. No significant alterations were found in regional cortical perfusion, indicating that the increased binding index was not a consequence of increased tracer delivery. This study supports a role for the serotonergic system in canine impulsive aggression. (orig.)

  12. Synthesis and Characterization of Rhenium(V) Complexes Having 3-(4-m-Chlorophenylpiperazin-1-yl)butane-1-thiol as Coligand toward 5HT2A Specific Radiopharmaceuticals

    International Nuclear Information System (INIS)

    Many imaging agents suitable for positron emission tomography bearing 11C and 18F as a radiotracer were developed on the basis of known 5HT2A receptor antagonist. Imaging agents for single photon emission computed tomography (SPECT) labeled with 123I or 125I were also developed. Preparation of technetium-99m-labeled imaging agent for the 5HT2A receptor stems from mimicking the receptor binding compounds as biologically active molecules (BAMs) which bind to the metals to form proper metal complex with other ligands to accommodate all coordination sites. A novel '3+1' mixed ligand rhenium oxo complex can be generated from the combination of tridentate ligand and monodentate BAM. A few reports describe the synthesis and evaluation of technetium(V) and rhenium(V) complex for 5HT2A serotonin receptor binding based on the ketanserin and its derivatives. A ligand used for BAM based on ketanserin can be designed on the basis of two structural units i. e. quinazoline as part A and phenyl piperidinyl ketone as part B. Either part A or B can be used for BAM while the other part goes as metal binding site

  13. The use of an antagonist 5-HT2a/c for depression and motor function in Parkinson' disease Uso de um antagonista 5-HT2a/c na depressão e na função motora de pacientes com doença de Parkinson

    Directory of Open Access Journals (Sweden)

    Antonio Luiz dos Santos Werneck

    2009-06-01

    Full Text Available OBJECTIVE: To test the ability of a 5HT2a/c (trazodone antagonist, to improve depression and motor function in Parkinson' disease (PD. METHOD: Twenty PD patients with and without depression were randomly assigned to receive trazodone (group 1 or not (group 2. They were evaluated through UPDRS and Hamilton Depression Rating Scale (HAM-D. RESULTS: For the UPDRS the mean score of group 2 was 33.1 ± 19.7 and 37.1 ± 18.0 at the end. For the group 1, the corresponding scores were 31.4 ± 11.3 and 25.9 ± 13.7. The variations in the Mann-Whitney test were 0.734 at the initial moment and 0.208 at the final moment. The variation in the comparison of the initial moment with the final moment was 0.005 providing statistical significance. For the HAM-D, the mean score went up 4 points in group 2, contrary to a 5.5 points decrease in group 1. CONCLUSION: Data analysis shows that this agent significantly improves depression, but the motor function improved only in the depressed patients. Because of the known anti-dopaminergic property of the 5-HT2c receptors, a possible approach for depression in PD could be the use of 5-HT2c antagonists, similarly to the use of atypical neuroleptics in case of psychotic symptoms.OBJETIVO: Avaliar a eficácia de um antagonista 5-HT2a/c (trazodona na depressão e na função motora de pacientes com doença de Parkinson (DP. MÉTODO: Vinte pacientes com DP com e sem depressão foram randomizados e divididos em 2 grupos com e sem a trazodona (grupos 1 e 2. Foram avaliados pela escala UPDRS e a de depressão de Hamilton (EDH. RESULTADOS: A média inicial do grupo 2 na UPDRS foi 33,1 ± 19,7 no momento inicial e 37,1 ± 18,0 no final. Para o grupo 1 as médias correspondentes foram 31,4 ± 11,3 e 25,9 ± 13,7. As variações no teste de Mann-Whitney foram 0,734 no momento inicial e de 0,208 no final. A variação na comparação entre o momento inicial e o final foi 0,005, caracterizando significância estatística. Para a EDH a

  14. Excess of transmission of the G allele of the -1438A/G polymorphism of the 5-HT2A receptor gene in patients with schizophrenia responsive to antipsychotics

    Directory of Open Access Journals (Sweden)

    Hamon Michel

    2008-05-01

    Full Text Available Abstract Background The -1438A/G polymorphism of the 5-HT2A gene has been found to be associated with clinical response to clozapine and other second generation antipsychotics. Testing the impact of this marker on response to first generation antipsychotics (which have a lower affinity for the 5-HT2A receptor provides the opportunity to help disentangling the two different roles that this polymorphism might have. A psychopharmacogenetic role should be detected only for antipsychotics with high affinity to the 5-HT2A receptor (therefore to second generation antipsychotics. An alternative role would imply tagging a subgroup of patients responsive to any antipsychotic, whatever their affinity, meaning that the association is more depending on non pharmacological charaterictics, such as clinical specificities. Methods A family-based sample of 100 Algerian patients with schizophrenia (according to DSM-IV criteria and their 200 biological parents was recruited, in order to avoid stratification biases. Patients were all treated, or have been treated, by conventional antipsychotics (mainly haloperidol for at least four weeks, at appropriate dosage. May and Dencker scale was used to distinguish responders and non responders. Results No allele of the -1438A/G polymorphism of the 5-HT2A gene was transmitted in excess (50 transmitted for 38 untransmitted in the whole sample of patients with schizophrenia (p = .90. In contrast, a significant excess of transmission of the G allele was observed (p = .02 in the subgroup of patients with good treatment response (17 transmitted for 6 untransmitted. Conclusion Using a TDT approach, we showed that the G allele of the -1438A/G polymorphism of the gene coding for the 5-HT2A receptor was associated to schizophrenia with good response to conventional antipsychotics, although this conclusion is based on 88 informative patients only. Because previous data showed the same result with atypical antipsychotics, it can be

  15. Expression of 5-HT and 5-HT2A receptor in rat hippocampus%大鼠海马内5-羟色胺及其受体5-HT2A的表达

    Institute of Scientific and Technical Information of China (English)

    易传安; 胡祥上; 马晓凯; 岳晓玲; 马广; 王滨

    2011-01-01

    Objective: To observe the distribution of the serotoninergic (5-HT) fibers and 5-HT2A receptor in CA1, CA2 and CA3 regions of the rat hippcampus. Methods: The distribution and expression of 5-HT and 5-HT2A receptor were detected by immunohistochemical staining against 5-HT transmitter and 5-HT2A antibodies, and then analyzed with image system. Results: In the hippocampus, the immunoreactive products of 5-HT2A was located in the cell membrane and den-drites of pyramidal cells, especially in dendrites. The 5-HT2A receptor immunoreactive neurons were distributed dominantly in pyramidal cells in Cal, CA2 and CA3 (CA2>CA3>CA1) (P<0. 01). The linear positive products against 5-HT were found in nerve fibers and terminals in Cal, CA2 and CA3 of hippocampus. No positive products of 5-HT2A receptor were found in nerve fibers and terminals in Cal, CA2 and CA3 of hippocampus. Conclusion: 5-HT2A widely distributes in the hippocampus Cal, CA2 and CA3, and can response the regulation of extrinsic 5-HT neurotransmitter.%目的:观察5-羟色胺(5-HT)纤维和5-HT2A受体在大鼠海马CA1、CA2和CA3三个区域的分布特点.方法:用5-HT递质和5-HT2A受体特异性抗体的免疫组织化学显色以及图像处理与分析.结果:在海马内,抗5-HT2A受体的免疫反应阳性产物主要位于锥体细胞的细胞膜和树突,树突染色较深;5-HT2A受体的阳性胞体在CA1、CA2和CA3的分布不均匀,以锥体层细胞分布最多,CA2>CA3>CA1,CA2与CA1之间,CA3与CA1之间比较差异有统计学意义;在海马的CA1、CA2和CA3区可见呈线状的5-HT递质阳性神经纤维及其终末;在海马的CA1、CA2和CA3未见呈点状或线状的5-HT2A受体阳性神经纤维及终末表达.结论:5-HT2A受体广泛分布在海马CA1、CA2和CA3区,可以接受外来5-HT递质的调控.

  16. Gene Therapy by Targeted Adenovirus-mediated Knockdown of Pulmonary Endothelial Tph1 Attenuates Hypoxia-induced Pulmonary Hypertension

    OpenAIRE

    Morecroft, Ian; White, Katie; Caruso, Paola; Nilsen, Margaret; Loughlin, Lynn; Alba, Raul; Reynolds, Paul N; Danilov, Sergei M.; Andrew H. Baker; MacLean, Margaret R.

    2012-01-01

    Serotonin is produced by pulmonary arterial endothelial cells (PAEC) via tryptophan hydroxylase-1 (Tph1). Pathologically, serotonin acts on underlying pulmonary arterial cells, contributing to vascular remodeling associated with pulmonary arterial hypertension (PAH). The effects of hypoxia on PAEC-Tph1 activity are unknown. We investigated the potential of a gene therapy approach to PAH using selective inhibition of PAEC-Tph1 in vivo in a hypoxic model of PAH. We exposed cultured bovine pulmo...

  17. Association Study between Promoter Polymorphism of TPH1 and Progression of Idiopathic Scoliosis

    Science.gov (United States)

    Yablanski, Vasil; Nikolova, Svetla; Vlaev, Evgeni; Savov, Alexey; Kremensky, Ivo

    2016-01-01

    The concept of disease-modifier genes as an element of genetic heterogeneity has been widely accepted and reported. The aim of the current study is to investigate the association between the promoter polymorphism TPH1 (rs10488682) and progression of idiopathic scoliosis (IS) in Eastern European population sample. A total of 105 patients and 210 healthy gender-matched controls were enrolled in this study. The TPH1 promoter polymorphism was genotyped by amplification followed by restriction. The statistical analysis was performed by Fisher's Exact Test. The results indicated that the genotypes and alleles of TPH1 (rs10488682) are not correlated with curve severity, curve pattern, or bracing. Therefore, the examined polymorphic variant could not be considered as a genetic factor with modifying effect of IS. In conclusion, this case-control study revealed no statistically significant association between TPH1 (rs10488682) and progression of IS in Eastern European population sample. These preliminary results should be replicated in extended population studies including larger sample sizes. The identification of molecular markers for IS could be useful for a more accurate prognosis of the risk for a rapid progression of the curve. That would permit early stage treatment of the patient with the least invasive procedures. PMID:27293961

  18. Association Study between Promoter Polymorphism of TPH1 and Progression of Idiopathic Scoliosis

    Directory of Open Access Journals (Sweden)

    Vasil Yablanski

    2016-01-01

    Full Text Available The concept of disease-modifier genes as an element of genetic heterogeneity has been widely accepted and reported. The aim of the current study is to investigate the association between the promoter polymorphism TPH1 (rs10488682 and progression of idiopathic scoliosis (IS in Eastern European population sample. A total of 105 patients and 210 healthy gender-matched controls were enrolled in this study. The TPH1 promoter polymorphism was genotyped by amplification followed by restriction. The statistical analysis was performed by Fisher’s Exact Test. The results indicated that the genotypes and alleles of TPH1 (rs10488682 are not correlated with curve severity, curve pattern, or bracing. Therefore, the examined polymorphic variant could not be considered as a genetic factor with modifying effect of IS. In conclusion, this case-control study revealed no statistically significant association between TPH1 (rs10488682 and progression of IS in Eastern European population sample. These preliminary results should be replicated in extended population studies including larger sample sizes. The identification of molecular markers for IS could be useful for a more accurate prognosis of the risk for a rapid progression of the curve. That would permit early stage treatment of the patient with the least invasive procedures.

  19. Inhibition of SNL-induced upregulation of CGRP and NPY in the spinal cord and dorsal root ganglia by the 5-HT(2A) receptor antagonist ketanserin in rats.

    Science.gov (United States)

    Wang, Dongmei; Chen, Tingjun; Gao, Yun; Quirion, Rémi; Hong, Yanguo

    2012-05-01

    Our previous study has demonstrated that topical and systemic administration of the 5-HT(2A) receptor antagonist ketanserin attenuates neuropathic pain. To explore the mechanisms involved, we examined whether ketanserin reversed the plasticity changes associated with calcitonin gene-related peptides (CGRP) and neuropeptide Y (NPY) which may reflect distinct mechanisms: involvement and compensatory protection. Behavioral responses to thermal and tactile stimuli after spinal nerve ligation (SNL) at L5 demonstrated neuropathic pain and its attenuation in the vehicle- and ketanserin-treated groups, respectively. SNL surgery induced an increase in CGRP and NPY immunoreactivity (IR) in laminae I-II of the spinal cord. L5 SNL produced an expression of NPY-IR in large, medium and small diameter neurons in dorsal root ganglion (DRG) only at L5, but not adjacent L4 and L6. Daily injection of ketanserin (0.3 mg/kg, s.c.) for two weeks suppressed the increase in CGRP-IR and NPY-IR in the spinal cord or DRG. The present study demonstrated that: (1) the expression of CGRP was enhanced in the spinal dorsal horn and NPY was expressed in the DRG containing injured neurons, but not in the adjacent DRG containing intact neurons, following L5 SNL; (2) the maladaptive changes in CGRP and NPY expression in the spinal cord and DRG mediated the bioactivity of 5-HT/5-HT(2A) receptors in neuropathic pain and (3) the blockade of 5-HT(2A) receptors by ketanserin reversed the evoked upregulation of both CGRP and NPY in the spinal cord and DRG contributing to the inhibition of neuropathic pain.

  20. The highly selective 5-hydroxytryptamine (5-HT)2A receptor antagonist, EMD 281014, significantly increases swimming and decreases immobility in male congenital learned helpless rats in the forced swim test.

    Science.gov (United States)

    Patel, Jignesh G; Bartoszyk, Gerd D; Edwards, Emmeline; Ashby, Charles R

    2004-04-01

    We examined the effect of the highly selective 5-hydroxytryptamine (5-HT)(2A) receptor antagonist 7-[4-[2-(4-fluoro-phenyl)-ethyl]-piperazine-1-carbonyl]-1H-indole-3-carbonitrile HCl (EMD 281014) in congenital learned helpless male rats in the forced swim test. The administration of EMD-281014 (0.3-30 mg/kg i.p.) to congenital learned helpless rats dose-dependently and significantly (at 10 and 30 mg/kg) decreased immobility and increased swimming compared to vehicle-treated animals. Thus, EMD 281014 produces effects in the forced swim test resembling those of antidepressants.

  1. Tph2 gene deletion enhances amphetamine-induced hypermotility: effect of 5-HT restoration and role of striatal noradrenaline release.

    Science.gov (United States)

    Carli, Mirjana; Kostoula, Chrysaugi; Sacchetti, Giuseppina; Mainolfi, Pierangela; Anastasia, Alessia; Villani, Claudia; Invernizzi, Roberto William

    2015-11-01

    Variants of tryptophan hydroxylase-2 (Tph2), the gene encoding enzyme responsible for the synthesis of brain serotonin (5-HT), have been associated with neuropsychiatric disorders, substance abuse and addiction. This study assessed the effect of Tph2 gene deletion on motor behavior and found that motor activity induced by 2.5 and 5 mg/kg amphetamine was enhanced in Tph2(-/-) mice. Using the in vivo microdialysis technique we found that the ability of amphetamine to stimulate noradrenaline (NA) release in the striatum was reduced by about 50% in Tph2(-/-) mice while the release of dopamine (DA) was not affected. Tph2 deletion did not affect the release of NA and DA in the prefrontal cortex. The role of endogenous 5-HT in enhancing the effect of amphetamine was confirmed showing that treatment with the 5-HT precursor 5-hydroxytryptophan (10 mg/kg) restored tissue and extracellular levels of brain 5-HT and the effects of amphetamine on striatal NA release and motor activity in Tph2(-/-) mice. Treatment with the NA precursor dihydroxyphenylserine (400 mg/kg) was sufficient to restore the effect of amphetamine on striatal NA release and motor activity in Tph2(-/-) mice. These findings indicate that amphetamine-induced hyperactivity is attenuated by endogenous 5-HT through the inhibition of striatal NA release. Tph2(-/-) mice may be a useful preclinical model to assess the role of 5-HT-dependent mechanisms in the action of psychostimulants. Acute sensitivity to the motor effects of amphetamine has been associated to increased risk of psychostimulant abuse. Here, we show that deletion of Tph2, the gene responsible for brain 5-HT synthesis, enhances the motor effect of amphetamine in mice through the inhibition of striatal NA release. This suggests that Tph2(-/-) mice is a useful preclinical model to assess the role of 5-HT-dependent mechanisms in psychostimulants action. Tph2, tryptophan hydroxylase-2.

  2. The serotonergic hallucinogen 5-methoxy-N,N-dimethyltryptamine disrupts cortical activity in a regionally-selective manner via 5-HT(1A) and 5-HT(2A) receptors.

    Science.gov (United States)

    Riga, Maurizio S; Bortolozzi, Analia; Campa, Letizia; Artigas, Francesc; Celada, Pau

    2016-02-01

    5-Methoxy-N,N-dimethyltryptamine (5-MeO-DMT) is a natural hallucinogen, acting as a non-selective serotonin 5-HT(1A)/5-HT(2A)-R agonist. Psychotomimetic agents such as the non-competitive NMDA-R antagonist phencyclidine and serotonergic hallucinogens (DOI and 5-MeO-DMT) disrupt cortical synchrony in the low frequency range (DMT on low frequency cortical oscillations (LFCO, DMT reduced LFCO in the PFC of WT and KO2A mice. The effect in KO2A mice was fully prevented by the 5-HT(1A)-R antagonist WAY-100635. Systemic and local 5-MeO-DMT reduced 5-HT release in PFC mainly via 5-HT(1A)-R. Moreover, 5-MeO-DMT reduced LFCO in S1, Au1 and V1 of WT mice and only in V1 of KO2A mice, suggesting the involvement of 5-HT(1A)-R activation in the 5-MeO-DMT-induced disruption of V1 activity. In addition, antipsychotic drugs reversed 5-MeO-DMT effects in WT mice. The present results suggest that the hallucinogen action of 5-MeO-DMT is mediated by simultaneous alterations of the activity of sensory (S1, Au1, V1) and associative (PFC) cortical areas, also supporting a role of 5-HT(1A)-R stimulation in V1 and PFC, in addition to the well-known action on 5-HT(2A)-R. Moreover, the reversal by antipsychotic drugs of 5-MeO-DMT effects adds to previous literature supporting the usefulness of the present model in antipsychotic drug development. PMID:26477571

  3. The Combination of Marketed Antagonists of α1b-Adrenergic and 5-HT2A Receptors Inhibits Behavioral Sensitization and Preference to Alcohol in Mice: A Promising Approach for the Treatment of Alcohol Dependence.

    Directory of Open Access Journals (Sweden)

    Fabrice Trovero

    Full Text Available Alcohol-dependence is a chronic disease with a dramatic and expensive social impact. Previous studies have indicated that the blockade of two monoaminergic receptors, α1b-adrenergic and 5-HT2A, could inhibit the development of behavioral sensitization to drugs of abuse, a hallmark of drug-seeking and drug-taking behaviors in rodents. Here, in order to develop a potential therapeutic treatment of alcohol dependence in humans, we have blocked these two monoaminergic receptors by a combination of antagonists already approved by Health Agencies. We show that the association of ifenprodil (1 mg/kg and cyproheptadine (1 mg/kg (α1-adrenergic and 5-HT2 receptor antagonists marketed as Vadilex ® and Periactine ® in France, respectively blocks behavioral sensitization to amphetamine in C57Bl6 mice and to alcohol in DBA2 mice. Moreover, this combination of antagonists inhibits alcohol intake in mice habituated to alcohol (10% v/v and reverses their alcohol preference. Finally, in order to verify that the effect of ifenprodil was not due to its anti-NMDA receptors property, we have shown that a combination of prazosin (0.5 mg/kg, an α1b-adrenergic antagonist, Mini-Press ® in France and cyproheptadine (1 mg/kg could also reverse alcohol preference. Altogether these findings strongly suggest that combined prazosin and cyproheptadine could be efficient as a therapy to treat alcoholism in humans. Finally, because α1b-adrenergic and 5-HT2A receptors blockade also inhibits behavioral sensitization to psychostimulants, opioids and tobacco, it cannot be excluded that this combination will exhibit some efficacy in the treatment of addiction to other abused drugs.

  4. Cellular resilience: 5-HT neurons in Tph2(-/-) mice retain normal firing behavior despite the lack of brain 5-HT.

    Science.gov (United States)

    Montalbano, Alberto; Waider, Jonas; Barbieri, Mario; Baytas, Ozan; Lesch, Klaus-Peter; Corradetti, Renato; Mlinar, Boris

    2015-11-01

    Considerable evidence links dysfunction of serotonin (5-hydroxytryptamine, 5-HT) transmission to neurodevelopmental and psychiatric disorders characterized by compromised "social" cognition and emotion regulation. It is well established that the brain 5-HT system is under autoregulatory control by its principal transmitter 5-HT via its effects on activity and expression of 5-HT system-related proteins. To examine whether 5-HT itself also has a crucial role in the acquisition and maintenance of characteristic rhythmic firing of 5-HT neurons, we compared their intrinsic electrophysiological properties in mice lacking brain 5-HT, i.e. tryptophan hydroxylase-2 null mice (Tph2(-/-)) and their littermates, Tph2(+/-) and Tph2(+/+), by using whole-cell patch-clamp recordings in a brainstem slice preparation and single unit recording in anesthetized animals. We report that the active properties of dorsal raphe nucleus (DRN) 5-HT neurons in vivo (firing rate magnitude and variability; the presence of spike doublets) and in vitro (firing in response to depolarizing current pulses; action potential shape) as well as the resting membrane potential remained essentially unchanged across Tph2 genotypes. However, there were subtle differences in subthreshold properties, most notably, an approximately 25% higher input conductance in Tph2(-/-) mice compared with Tph2(+/-) and Tph2(+/+) littermates (p<0.0001). This difference may at least in part be a consequence of slightly bigger size of the DRN 5-HT neurons in Tph2(-/-) mice (approximately 10%, p<0.0001). Taken together, these findings show that 5-HT neurons acquire and maintain their signature firing properties independently of the presence of their principal neurotransmitter 5-HT, displaying an unexpected functional resilience to complete brain 5-HT deficiency. PMID:26409296

  5. Hallucinogen-like effects of 2-([2-(4-cyano-2,5-dimethoxyphenyl) ethylamino]methyl)phenol (25CN-NBOH), a novel N-benzylphenethylamine with 100-fold selectivity for 5-HT2A receptors, in mice

    DEFF Research Database (Denmark)

    Fantegrossi, William E; Gray, Bradley W; Bailey, Jessica M;

    2015-01-01

    characterized. OBJECTIVE: 25CN-NBOH was compared to the traditional phenethylamine hallucinogen R(-)-2,5-dimethoxy-4-iodoamphetamine (DOI) using mouse models of drug-elicited head twitch behavior and drug discrimination. METHODS: Drug-elicited head twitches were quantified for 10 min following administration...... of various doses of either DOI or 25CN-NBOH, with and without pretreatments of 0.01 mg/kg 5-HT2A antagonist M100907 or 3.0 mg/kg 5-HT2C antagonist RS102221. The capacity of 25CN-NBOH to attenuate DOI-elicited head twitch was also investigated. Mice were trained to discriminate DOI or M100907 from saline......, and 25CN-NBOH was tested for generalization. RESULTS: 25CN-NBOH induced a head twitch response in the mouse that was lower in magnitude than that of DOI, blocked by M100907, but not altered by RS102221. DOI-elicited head twitch was dose-dependently attenuated by 25CN-NBOH pretreatment. 25CN-NBOH produced...

  6. Connections between 5-HT-containing terminals and 5-HT2A receptor and γ-aminobutyric acid or glycine co-existed neurons in the rat medullary dorsal horn

    Institute of Scientific and Technical Information of China (English)

    LI Hui; LI Yun-qing

    2001-01-01

    Objective: To investigate the connections between serotonin (5-HT)-containing terminals and 5-HT2A receptor (5-HT2AR)/γ-aminobutyric acid (GABA) or 5-HT2AR/glycine co-existed neurons in the rat medullary dorsal horn (MDH).Methods: Immunofluorescence histochemical triple-staining for 5-HT, 5-HT2AR, GABA or glycine. Results: 5-HT-immunoreaetive fibers and terminals were chiefly located in the superficial laminae (laminae Ⅰ and Ⅱ) of the MDH. Neurons exhibiting 5-HT2AR-, GABA- or glycine-immunoreactivities were mainly observed in the superficial laminae. Some 5-HT2AR-immunopositive neurons also exhibited GABA- or glycine-immunoreaetivities. 5-HT-containing terminals made close contacts with 5-HT2AR/GABA or 5-HT2AR/glycine co-existed neurons. Conclusion: 5-HT2AR/GABA or 5-HT2AR /glycine co-exist in some of the neurons in the superficial laminae of the MDH. 5-HT-immunoreactive terminals form close connections with 5-HT2AR/GABA or 5-HT2AR/glycine co-existed neurons.

  7. Brain structures implicated in the four-plate test in naïve and experienced Swiss mice using injection of diazepam and the 5-HT2A agonist DOI.

    Science.gov (United States)

    Petit-Demoulière, Benoit; Massé, Fabienne; Cogrel, Nicolas; Hascoët, Martine; Bourin, Michel

    2009-12-01

    Four-plate test-retest (FPT-R) is a useful tool to study aversive memory and abolishment of benzodiazepine effects in experienced mice to four-plate test (FPT), namely one-trial tolerance. In the present study, we have used local injections paradigm, in order to localize structures implied in anxiolytic-like effects of two drugs in naïve and experienced mice: a benzodiazepine, diazepam that is only active in naïve mice; and a 5-HT(2A/2C) agonist, DOI that exert its anxiolytic-like effect both in naïve and experienced mice. Periacqueductal grey substance, three sub-regions of hippocampus (CA1, CA2 and CA3) and two nuclei of amygdala (BLA and LA) have been studied. Local injections did not cause any modifications of ambulatory activity. DOI injections elicit anxiolytic-like effects only when injected into CA2, in naïve and experienced mice. Diazepam had an anxiolytic-like effect in naïve mice, only when injected into lateral nucleus of amygdala; and in experienced mice when injected into PAG. These results help us to better understand the way of action of these two compounds and the structures functionally involved in their effects and in one-trial tolerance (OTT).

  8. Extending David Horrobin's membrane phospholipid theory of schizophrenia: overactivity of cytosolic phospholipase A(2) in the brain is caused by overdrive of coupled serotonergic 5HT(2A/2C) receptors in response to stress.

    Science.gov (United States)

    Eggers, Arnold E

    2012-12-01

    David Horrobin's membrane phospholipid theory of schizophrenia has held up well over time because his therapeutic prediction that dietary supplementation with eicosapentaenoic acid (EPA) would have a therapeutic effect has been partially verified and undergoes continued testing. In the final version of his theory, he hypothesized that there was hyperactivity of phosphoslipase A(2) (PLA(2)) or a related enzyme but did not explain how the hyperactivity came about. It is known that serotonergic 5HT(2A/2C) receptors are coupled to PLA(2), which hydrolyzes both arachidonic acid (AA) and EPA from diacylglycerides at the sn-2 position. In this paper, Horrobin's theory is combined with a previously published theory of chronic stress in which it was hypothesized that a disinhibited dorsal raphe nucleus, the principal nucleus of the serotonergic system, can organize the neuropathology of diseases such as migraine, hypertension, and the metabolic syndrome. The new or combined theory is that schizophrenia is a disease of chronic stress in which a disinhibited DRN causes widespread serotonergic overdrive in the cerebral cortex. This in turn causes overdrive of cPLA(2) and both central and peripheral depletion of AA and EPA. Because EPA is present in smaller amounts, it falls below threshold for maintaining an intracellular balance between AA-derived and EPA-derived second messenger cascades, which leads to abnormal patterns of neuronal firing. There are two causes of neuronal dysfunction: the disinhibited DRN and EPA depletion. Schizophrenia is statistically associated with metabolic syndrome, hypertension, and migraine because they form a cluster of diseases with similar pathophysiology. The theory provides an explanation for both the central and peripheral phospholipid abnormalities in schizophrenia. It also explains the role of stress in schizophrenia, elevated serum PLA(2) activity in schizophrenia, the relationship between untreated schizophrenia and metabolic syndrome

  9. Studies on the role of 5-HT2A and 5-HT2C receptor antagonist and effects of co-administration of Fluoxetines in regulating generalized seizures in albino rats

    Directory of Open Access Journals (Sweden)

    Vasant R Chavan

    2010-07-01

    Full Text Available Introduction: Epilepsy is due to imbalance between inhibitory & excitatory neurotransmitter release at synaptic level in brain such as GABA, Serotonin, Glutamate and nor epinephrine. Recently there are few reports suggesting that, 5-HT1A receptor antagonist with co-administration of fluoxetine has shown anticonvulsant activity. The present study is undertaken to evaluate the action of 5-HT2A/2C mediated anticonvulsant action of Trazodone in MES (Maximum Electro Shock model in albino rats. Materials & Methods: Fifty albino rats of 200-250 gms of either sex were divided into five groups each of 10 rats(n=10, Group–I received distil water 0.5ml oral, Group –II- received sodium valproate - 200mg/kg bw intra peritoneal(i.p.acted as positive control, Group –III- received Trazodone 54mg/bw, orally Group- IV- received sub-anticonvulsant dose of Fluoxetine 6mg/kg/bw i.p. Group- V- received Trazodone 54mg/kg/bw and Fluoxetine 6mg/kg bw. Subsequently all groups were subjected for MES. The results were analyzed by calculating the mean duration of convulsions & absence of HLE and comparison was done by student‘t’ test. Results: The present study revealed that sodium valproate showed 100% protection against MES as compared to negative control,(P<0.05. Trazodone showed 40% protection against MES& decrease in the duration of convulsions by 60%, and Fluoxitine sub-anticonvulsive dose combined with Trazodone 54 mg /kg b.w. has shown 90% protection against MES. The results are parallel to standard drug sodium valproate. Conclusion: Trazodone has exerted anticonvulsant activity, by enhancing 5-HT&NE extra cellular level in brain, and probably potentiated the action of sub anticonvulsive dose of fluoxetine in combination. However, further investigative studies are needed to confirm the potention of trazodone action.

  10. Antidepressive-drug-induced bodyweight gain is associated with polymorphisms in genes coding for COMT and TPH1

    DEFF Research Database (Denmark)

    Secher, Anna; Bukh, Jens; Bock, Camilla;

    2009-01-01

    of a single depressive episode and who were under antidepressive treatment. Weight gainers were identified based on rating with the Udvalg for Kliniske Undersøgelser Side Effect Rating Scale. Polymorphisms in catechol-O-methyltransferase, tryptophan hydroxylase (TPH1), serotonin receptor 2C (HTR2C......) and serotonin transporter (SLC6A4) genes were identified and associated with bodyweight gain during treatment. The AG genotype of catechol-O-methyltransferase rs4680 and the AA genotype of TPH1 rs18532 were significantly associated with bodyweight gain during antidepressive treatment, when adjusted for age...

  11. Changes of Serotonin (5-HT), 5-HT2A Receptor, and 5-HT Transporter in the Sprague-Dawley Rats of Depression,Myocardial Infarction and Myocardial Infarction Co-exist with Depression

    Institute of Scientific and Technical Information of China (English)

    Mei-Yan Liu; Yah-Ping Ren; Wan-Lin Wei; Guo-Xiang Tian; Guo Li

    2015-01-01

    Background:To evaluate whether serotonin (5-HT),5-HT2A receptor (5-HT2AR),and 5-HT transporter (serotonin transporter [SERT]) are associated with different disease states of depression,myocardial infarction (MI) and MI co-exist with depression in Sprague-Dawley rats.Methods:After established the animal model of four groups include control,depression,MI and MI with depression,we measured 5-HT,5-HT2AR and SERT from serum and platelet lysate.Results:The serum concentration of 5-HT in depression rats decreased significantly compared with the control group (303.25 ± 9.99 vs.352.98 ± 13.73;P =0.000),while that in MI group increased (381.78 ± 14.17 vs.352.98 ± 13.73;P =0.000).However,the depression + MI group had no change compared with control group (360.62 ± 11.40 vs.352.98 ± 13.73;P =0.036).The changes of the platelet concentration of 5-HT in the depression,MI,and depression + MI group were different from that of serum.The levels of 5-HT in above three groups were lower than that in the control group (380.40 ± 17.90,387.75 ± 22.28,246.40 ± 18.99 vs.500.29 ± 20.91;P =0.000).The platelet lysate concentration of 5-HT2AR increased in depression group,MI group,and depression + MI group compared with the control group (370.75 ± 14.75,393.47 ± 15.73,446.66 ± 18.86 vs.273.66 ± 16.90;P =0.000).The serum and platelet concentration of SERT in the depression group,MI group and depression + MI group were all increased compared with the control group (527.51 ± 28.32,602.02 ± 23.32,734.76 ± 29.59 vs.490.56 ± 16.90;P =0.047,P =0.000,P =0.000 in each and 906.38 ± 51.84,897.33 ± 60.34,1030.17 ± 58.73 vs.708.62 ± 51.15;P =0.000 in each).Conclusions:The concentration of 5-HT2AR in platelet lysate and SERT in serum and platelet may be involved in the pathway of MI with depression.Further studies should examine whether elevated 5-HT2AR and SERT may contribute to the biomarker in MI patients with depression.

  12. Posttranslational regulation of TPH1 is responsible for the nightly surge of 5-HT output in the rat pineal gland

    OpenAIRE

    Huang, Zheping; Liu, Tiecheng; Chattoraj, Asamanja; Ahmed, Samreen; Michael M Wang; Deng, Jie.; Sun, Xing; Borjigin, Jimo

    2008-01-01

    Serotonin (5-hydroxytryptamine, 5-HT), a precursor for melatonin production, is produced abundantly in the pineal gland of all vertebrate animals. The synthesis of 5-HT in the pineal gland is rate limited by tryptophan hydroxylase 1 (TPH1) whose activity displays a twofold increase at night. Earlier studies from our laboratory demonstrate that pineal 5-HT secretion exhibits dynamic circadian rhythms with elevated levels during the early night, and that the increase is controlled by adrenergic...

  13. Tryptophan hydroxylase gene 1 (TPH1) variants associated with cerebrospinal fluid 5-hydroxyindole acetic acid and homovanillic acid concentrations in healthy volunteers

    DEFF Research Database (Denmark)

    Andreou, Dimitrios; Saetre, Peter; Werge, Thomas;

    2010-01-01

    Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in serotonin synthesis. We investigated possible relationships between five TPH1 gene polymorphisms and cerebrospinal fluid (CSF) concentrations of the major serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA), the major dopamine...... metabolite homovanillic acid (HVA), and the major norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) in healthy volunteers (n=132). The G-allele of the TPH1 rs4537731 (A-6526G) polymorphism was associated with 5-HIAA and HVA, but not MHPG concentrations. None of the other four TPH1...

  14. 神经性厌食患者5-羟色胺2A受体基因多态性与人格特性的关联研究%An study on the association between 5-HT2A receptor gene polymorphism and personality traits in patients with anorexia nervosa

    Institute of Scientific and Technical Information of China (English)

    陈珏; 肖泽萍; 张明岛; 禹顺英; 贾秀珍; 张燃; 袁爱花; 钱伊萍; 虞一萍; 王振; 蒋文晖

    2012-01-01

    Objective To explore the relationship between 5-HT2A 102T/C polymorphism and personality traits in patients with anorexia nervosa. Methods The Multiplex SNaPshot SNP genotyping technique was used to analyze the genotypes of 5-HT2A 102T/C polymorphism and Minnesoda Multiphasic Personality Inventory (MMPI) was applied to measure the personality traits in 107 Chinese Han patients with anorexia nervosa. Results There were significant differences in the Pd (Psychopathic Deviate) T scores among the three genotype subgroups, i.e. C/C, T/T and T/C subgroup, of 5-HT2A 102T/C polymorphism (F = 7.698, P = 0.001). The Pd T scores was significantly higher in the homozygote genotype of both C/C and T/T (67.3 ± 12.7; 65.8 ± 12.7)than in either normal controls or in heterozygote genotype of T/C (58.2 ± 9.8) (P = 0.001 and P = 0.005, respectively). Conclusions S-HT^ 102T/C polymorphism is probably related with the susceptive personality traits of anorexia nervosa. The Pd T score of MMPI is the probable personality endophenotype in anorexia nervosa.%目的 探讨5-羟色胺2A(5-HT2A)受体基因102T/C多态性与神经性厌食患者人格特性之间的关系.方法 应用多重碱基延伸SNP分型技术,对107例神经性厌食患者进行5-HT2A 102T/C基因多态进行检测,并进行明尼苏达多项人格调查表(Minnesoda Multiphasic Personality Inventory,MMPI)评定.结果 5-HT2A 102T/C的三种多态基因型的Pd(心理病理性偏离)量表T分差异有统计学意义(F=7.698,P=0.001);其中,纯合子C/C和T/T基因型Pd量表T分(67.3±12.7;65.8±12.7)均高于中国常模(60),并均显著高于杂合子T/C基因型的Pd量表T分(58.2±9.8)(P1=0.001;P2=0.005).结论 5-HT2A102T/C基因多态可能与神经性厌食的易感人格特性存在关联,MMPI中Pd量表T分很可能是神经性厌食的人格特性内表型.

  15. Identification of Achaete-scute complex-like 1 (ASCL1 target genes and evaluation of DKK1 and TPH1 expression in pancreatic endocrine tumours

    Directory of Open Access Journals (Sweden)

    Skogseid Britt

    2009-09-01

    Full Text Available Abstract Background ASCL1 role in pancreatic endocrine tumourigenesis has not been established. Recently it was suggested that ASCL1 negatively controls expression of the Wnt signalling antagonist DKK1. Notch signalling regulates expression of TPH1, the rate limiting enzyme in the biosyntesis of serotonin. Understanding the development and proliferation of pancreatic endocrine tumours (PETs is essential for the development of new therapies. Methods ASCL1 target genes in the pancreatic endocrine tumour cell line BON1 were identified by RNA interference and microarray expression analysis. Protein expressions of selected target genes in PETs were evaluated by immunohistochemistry. Results 158 annotated ASCL1 target genes were identified in BON1 cells, among them DKK1 and TPH1 that were negatively regulated by ASCL1. An inverse relation of ASCL1 to DKK1 protein expression was observed for 15 out of 22 tumours (68%. Nine tumours displayed low ASCL1/high DKK1 and six tumours high ASCL1/low DKK1 expression. Remaining PETs showed high ASCL1/high DKK1 (n = 4 or low ASCL1/low DKK1 (n = 3 expression. Nine of twelve analysed PETs (75% showed TPH1 expression with no relation to ASCL1. Conclusion A number of genes with potential importance for PET tumourigenesis have been identified. ASCL1 negatively regulated the Wnt signalling antagonist DKK1, and TPH1 expression in BON1 cells. In concordance with these findings DKK1 showed an inverse relation to ASCL1 expression in a subset of PETs, which may affect growth control by the Wnt signalling pathway.

  16. 5-HT2A受体在尼可刹米增强新生大鼠延髓脑片呼吸放电中的作用%Role of 5-HT2A receptor in increase in respiratory-related rhythmic discharge activity by nikethamide in neonatal rat transverse medullary slices

    Institute of Scientific and Technical Information of China (English)

    千智斌; 吴中海

    2008-01-01

    本文旨在探讨中枢呼吸兴奋剂尼可刹米对新生大鼠基本节律性呼吸的产生和调节的影响及5-HT2A受体在其中的作用.制作新生大鼠离体延髓脑片标本,含面神经后核内侧区(the medial region of the nucleus retrofacialis,mNRF)并保留舌下神经根,灌流改良Kreb'S液(modified Kreb'S solution,MKS),记录舌下神经根呼吸相关节律性放电活动(respiratory-re-lated rhythmic discharge activity,RRDA),观察不同浓度尼可刹米、5-HT2A受体特异激动剂2,5-二甲氧基-4-碘苯基丙烷[1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane,DOI]、5-HT2A受体特异拮抗剂酮舍林(ketanserine)以及联合使用尼可刹米和酮舍林对舌下神经根RRDA的影响.结果显示,尼可刹米在0.5~7μg/mL时对延髓脑片RRDA有兴奋作用,在5 μg/mL时对吸气时程(inspiratory time,TI)、放电积分幅度(integral amplitude,IA)、呼吸周期(respiratory cycle,Re)等呼吸指标综合效果最显著.DOI明显延长TI、增强IA、缩短RC,对RRDA有兴奋作用.酮舍林明显缩短TI、减弱IA、延长RC,对RRDA有抑制作用.联合使用DOI和酮舍林对RRDA无明显作用.酮舍林可完全阻断尼可刹米对RC的作用,部分阻断尼可刹米对IA的作用,对尼可刹米引起的TI变化无明显影响.结果提示,尼可刹米增强新生大鼠离体延髓脑片舌下神经根RRDA,5-HT2A受体可能足尼可刹米作用途径之一.%To investigate the effects of nikethamide on the generation and modulation of rhythmic respiration of neonatal rats and therole of 5-HT2A receptor in this course, experiments were performed on the transverse medullary slices of neonatal rats (both sexes, 1-3 d) in vitro. The slices containing the medial region of the nucleus retrofacialis (mNRF) with the hypoglossal nerve rootlets were preparedin which the respiratory-related rhythmic discharge activity (RRDA) was recorded from the hypoglossal nerve rootlets by suctionelectrode. The possible role of nikethamide

  17. Genetic Polymorphisms of SNP Loci in the 5' and 3' Region of TPH2 Gene in Northern Chinese Han Population%中国北方汉族群体TPH2基因5'和3'端SNP位点遗传多态性

    Institute of Scientific and Technical Information of China (English)

    徐晓明; 丁梅; 庞灏; 邢佳鑫; 宣金锋; 王保捷

    2013-01-01

    Objective To investigate the genetic polymorphism in the 5' and 3' region of TPH2 gene of Northern Chinese Han population and to explore its application value in forensic medicine. Methods The sequence variants and the genetic polymorphisms of 6 SNP loci (rs4570625,rsl 1178997,rsl 1178998,rs41317118,rsl7110747 and rs41317114) within a 905 bp 5' flanking region and a 1 104 bp 3' flanking region of TPH2 gene were analyzed by DNA sequencing in a total of 244 unrelated healthy individuals in Northern Chinese Han population. The statistical analysis was carried out by Haploview v4.2 software. Results The genotypic distributions of the 6 SNP loci in the TPH2 gene were in accordance with Hardy-Weinberg equilibrium. One C/T variant in 92922 site was found. There was a high linkage disequilibrium among the 3 SNP loci (rs4570625,rsl 1178997 and rsl 1178998) in the 5' region and the 3 SNP loci (rs41317118,rsl7110747 and rs41317114) in the 3' region of TPH2 gene,respectively. The parameters of population genetics of 6 SNP loci were obtained. Conclusion There are great polymorphisms in the 5' and 3' region of TPH2 gene in Northern Chinese Han population,which could be used as genetic indexes for association analysis of the related diseases,as well as for forensic individual identification and paternity testing.%目的 调查中国北方汉族群体TPH2基因5’和3’端SNP位点遗传多态性并探讨其法医学应用价值.方法 测序分析244例中国北方健康无关个体TPH2基因5’端905 bp和3’端1104bp两个靶片段的序列特征和6个SNP位点(rs4570625、rs11178997、rs11178998、rs41317118、rs17110747和rs41317114)的遗传多态性,应用Haploview v4.2软件进行统计分析. 结果 244例中国北方汉族个体6个SNP位点基因型分布均符合Hardy-Weinberg平衡定律,在92922位点检测到1例C/T变异,TPH2基因5’端3个SNP位点(rs4570625、rs11178997和rs11178998)和3’端3个SNP位点(rs41317118、rs17110747和rs41317114)分别显示

  18. Modulation of 5-HT2A receptors on rhythmic respiration discharge activity in the transverse medullary slice of neonatal rats%5-羟色氨2A受体对新生大鼠延髓脑片节律性呼吸放电的调制作用

    Institute of Scientific and Technical Information of China (English)

    千智斌; 姬明丽; 吴中海

    2008-01-01

    目的 探讨5-羟色氨2A(5-HT2A)受体对新生大鼠延髓脑片节律性呼吸放电的调制作用.方法 制作新生大鼠离体延髓脑片标本,给予灌流恒温改良Kreb's液,记录舌下神经根呼吸相关节律性放电活动(RRDA).标本分2组:第1组使用含5-HT2A受体特异激动剂2,5-二甲氧基-4-碘苯基丙烷(DOI)的Kreb's液灌流脑片,观察其对RRDA的影响;第2组使用含5-HT2A受体特异拮抗剂酮舍林的Kreb's液灌流脑片,观察其对RRDA的影响.结果 DOI延长RRDA吸气放电时程(TI)、缩短呼气时程(TE)、缩短呼吸周期(RC)、增强RRDA放电积分幅度(IA),对RRDA有兴奋作用(P<0.01).酮舍林缩短RRDA的TI,延长TE和RC、减弱IA,对RRDA有抑制作用(P<0.01).结论 5-HT2A受体参与了新生大鼠基本呼吸节律的产生和调节.

  19. Is there a link between Depressive Disorders and Tryptophan Hydroxylase 1 (TPH1) Gene Polymorphism? - Study from a Distressed Area, Kashmir (India)

    Science.gov (United States)

    Tarfarosh, Shah Faisal Ahmad; Dar, Mohammad Maqbool; Hussain, Arshad; Shoib, Sheikh; Shah, Tabindah; Shah, Sahil; Manzoor, Mushbiq

    2016-01-01

    Background The progress that man has made in all domains of life, during all these years of reign over the earth, is utterly remarkable. However, it always came at a price. Each epoch of progress has seen human beings inflicted with trauma and cynical consequences. During the last two decades, Kashmiri (Indian) people have experienced continuous violence, a reign of terror, and political turmoil. Each of these disastrous events has contributed to the increase in psychiatric disorders in this part of the world, especially major depressive disorders. We can observe that besides the environmental influences, gene polymorphism also plays a crucial role in the development of depressive disorders. The role of Tryptophan Hydroxylase 1 (TPH1) gene is implicated in various psychiatric disorders, including depression. However, no study has investigated TPH1 A779C gene polymorphism in depressive disorders in a distressed society like Kashmir (India). Aims To study TPH1 A779C single nucleotide polymorphism in depressive disorders in Kashmiri (Indian) population. Materials and Methods Two hundred and forty patients diagnosed with depressive disorder, and 160 unrelated healthy volunteers (control), were studied in a case-control study design. Polymorphism was determined using polymerase chain reaction (PCR) and agarose gel electrophoresis, after digestion with HAP II enzyme. Genotypes and allele frequencies were compared using Chi-square tests, Fisher’s exact test, odds ratio, 95% confidence interval (C.I.) and a p-value of <0.05 was considered to be statistically significant. Results The mean age ± standard deviation (SD) of depression and control group was 32.02±10.99 and 31.75±9.93, respectively (p= 0.512). It was found that the patients from depression group had AA genotype (51.7%) in comparison to control group (17.5%) and these results were statistically significant (p≤0.0001). Calculation of allelic frequency revealed a stronger association of A allele with

  20. The tryptophan hydroxylase 1 (TPH1) gene, schizophrenia susceptibility, and suicidal behavior: a multi-centre case-control study and meta-analysis

    DEFF Research Database (Denmark)

    Saetre, Peter; Lundmark, Per; Wang, August;

    2010-01-01

    affected individuals having attempted suicide at least once and patients with no history of suicide attempts (P = 0.84). A systematic literature review and meta-analysis support the A218C polymorphism as a susceptibility locus for schizophrenia (odds ratio 1.17, 95% confidence interval 1......Serotonin (5-hydroxytryptamin; 5-HT) alternations has since long been suspected in the pathophysiology of schizophrenia. Tryptophan hydroxylase (tryptophan 5-monooxygenase; TPH) is the rate-limiting enzyme in the biosynthesis of 5-HT, and sequence variation in intron 6 of the TPH1 gene has been...

  1. Therapeutic effect of lithium salt and changes in receptor binding force of platelet 5-HT2A in bipolar affective psychosis and schizoaffective psychosis%双相情感性和分裂情感性精神病患者血小板5-H T2 A受体结合力变化及锂盐治疗效果观察

    Institute of Scientific and Technical Information of China (English)

    周鑫; 李康智; 秦群生

    2015-01-01

    Objective It is to observe the changes of platelet 5-HT2A receptor binding force and the effect of lithium salt in bipolar and schizoaffective psychosis.Methods 23 patients with bipolar affective psychosis and 23 patients with schizoaffec-tive psychosis were selected to observation group, 46 cases of schizophrenia patients were selected to control group.The plate-let 5-HT2A receptor binding force was measured by isotope ligand binding assay in two groups.The degree of depression and anxiety were assessed with Hamilton Depression Scale ( HAMD) and Hamilton Anxiety Scale ( HAMA) , to identify patients with suicidal behavior and Dutch act, and judge the bipolar manic type, bipolar type, split type and split type manic depres-sion.Then the effect on treatment with lithium was observed.Results The platelet 5-HT2A receptor binding force in the ob-servation group were significantly higher than that in the control group (P<0.05).The platelet 5-HT2A receptor binding force of patients with suicidal behavior and Dutch act, dual phase depression and schizophrenia depression were markedly stronger than patients without suicidal behavior and Dutch act, bipolar manic and split manic respectively in observation group ( all P<0.05) .The effect of lithium treatment in effect is patients with suicidal behavior and Dutch act, and depression were significantly lower than that in patients with not suicidal behavior and Dutch act, and depression ( all P<0.05) .Conclusion The platelet 5-HT2A receptor binding capacity in patients with bipolar affective and schizoaffective psychosis are stronger than normal patients, and in patients with suicidal behavior and Dutch act are stronger than that with non suicidal behavior and Dutch act.The effect of lithium treatment in patients of higher platelet 5-HT2A receptor binding capacity is decreased than that of lower platelet 5-HT2A receptor binding force.%目的:研究双相情感性和分裂情感性精神病患者血小板5-HT2 A受体结合

  2. Influence of prenatal depression on TPH2 expression in median raphe nuclei of rats%妊娠期抑郁症对大鼠中缝核色氨酸羟化酶2表达的影响

    Institute of Scientific and Technical Information of China (English)

    徐晓明; 李秋玲; 那全; 崔红; 刘彩霞

    2011-01-01

    Objective To investigate influence of prenatal depression on expression of tryptophan hydroxylase 2 (TPH2) in median raphe nuclei of rats. Methods Adult pregnant Wistar rats, similar in age and body weight, were randomly divided into the experimental group and the control group. The rats of the experimental group were exposed to chronic unexpected mild stress (CUMS) for 18 days to establish an animal model. Behavior scores were assessed by the open-field test and fluid consumption test. Expression of TPH2 in median raphe nuclei was detected by the SP immuno-histochemical method. Results After 18 days of CUMS, the behavior score, amount of fluid consumption and expression of TPH2 in median raphe nuclei were significantly lower in the experimental group than those in the control group (all P <0.01). Expression of TPH2 was negatively correlated with the horizontal score (r = -0.71), vertical score (r = - 0.74) and sugar water consumption amount(r = -0.69), while positively correlated with stop time in the center (r = 0.64). Conclusion Decreased expression of TPH2 in median raphe nuclei of depressive pregnant rats may be related to prenatal depression.%目的 探讨妊娠期抑郁症对大鼠中缝核色氨酸羟化酶2(TPH2)表达的影响.方法 选取月龄、体质量相近的Wistar大鼠,合笼受孕后将孕鼠随机分为实验组、对照组.实验组给予18d慢性不可预见性的温和应激(CUMS)制备妊娠期抑郁症大鼠模型,对照组在正常条件下饲养.采用旷场实验和1%蔗糖水偏爱实验对大鼠进行行为学评分,采用免疫组化SP法测定大鼠中缝核TPH2的表达.结果 18d CUMS后,实验组大鼠旷场实验评分、蔗糖水消耗实验结果及中缝核TPH2表达量低于对照组(P均<0.01).实验组大鼠18d CUMS前后水平运动得分差与TPH2表达量呈负相关(r=-0.71),垂直运动得分差与TPH2表达量呈负相关(r=-0.74),中央格停留时间差与TPH2表达量呈正相关(r=0.64),蔗糖水消耗量差与TPH

  3. Epistasis between IL1A, IL1B, TNF, HTR2A, 5-HTTLPR and TPH2 Variations Does Not Impact Alcohol Dependence Disorder Features

    Directory of Open Access Journals (Sweden)

    Anastasios Kalofoutis

    2009-07-01

    Full Text Available We assessed a set of biological (HDL, LDL, SGOT,SGPT, GGT, HTc, Hb and T levels and psychometric variables (investigated through HAM-D, HAM-A, GAS, Liebowitz Social Anxiety Scale, Mark & Mathews Scale, Leyton scale, and Pilowski scale in a sample of 64 alcohol dependent patients, at baseline and after a detoxification treatment. Moreover, we recruited 47 non-consanguineous relatives who did not suffer alcohol related disorders and underwent the same tests. In both groups we genotyped 11 genetic variations (rs1800587; rs3087258; rs1799724; 5-HTTLPR; rs1386493; rs1386494; rs1487275; rs1843809; rs4570625; rs2129575; rs6313 located in genes whose impact on alcohol related behaviors and disorders has been hypothesized (IL1A, IL1B, TNF, 5-HTTLPR, TPH2 and HTR2A. We analyzed the epistasis of these genetic variations upon the biological and psychological dimensions in the cases and their relatives. Further on, we analyzed the effects of the combined genetic variations on the short – term detoxification treatment efficacy. Finally, being the only not yet investigated variation within this sample, we analyzed the impact of the rs6313 alone on baseline assessment and treatment efficacy. We detected the following results: the couple rs6313 + rs2129575 affected the Leyton -Trait at admission (p = 0.01 (obsessive-compulsive trait, whilst rs1800587 + 5-HTTLPR impacted the Pilowski test at admission (p = 0.01 (hypochondriac symptoms. These results did not survive Bonferroni correction (p ≤ 0.004. This lack of association may depend on the incomplete gene coverage or on the small sample size which limited the power of the study. On the other hand, it may reflect a substantial absence of relevance of the genotype variants toward the alcohol related investigated dimensions. Nonetheless, the marginal significance we detected could witness an informative correlation worth investigating in larger samples.

  4. The 5-HT2A serotonin receptor in executive function: Implications for neuropsychiatric and neurodegenerative diseases.

    Science.gov (United States)

    Aznar, Susana; Hervig, Mona El-Sayed

    2016-05-01

    Executive function entails the interplay of a group of cognitive processes enabling the individual to anticipate consequences, attain self-control, and undertake appropriate goal-directed behaviour. Serotonin signalling at serotonin 2A receptors (5-HT2AR) has important effects on these behavioural and cognitive pathways, with the prefrontal cortex (PFC) as the central actor. Indeed, the 5-HT2ARs are highly expressed in PFC, where they modulate cortical activity and local network oscillations (brain waves). Numerous psychiatric and neurodegenerative diseases result in disrupted executive function. Animal and human studies have linked these disorders with alterations in the 5-HT2AR system, making this an important pharmacological target for the treatment of disorders with impaired cognitive function. This review aims to describe the current state of knowledge on the role of 5-HT2AR signalling in components of executive function, and how 5-HT2AR systems may relate to executive dysfunctions occurring in psychiatric and neurodegenerative diseases. We hope thereby to provide insight into how pharmacotherapy targeting the 5-HT2AR may ameliorate (or exacerbate) aspects of these disorders. PMID:26891819

  5. Current radiosynthesis strategies for 5-HT2A receptor PET tracers

    DEFF Research Database (Denmark)

    Herth, Matthias M; Knudsen, Gitte M

    2015-01-01

    Serotonin 2A receptors have been implicated in various psychophysiological functions and disorders such as depression, Alzheimer's disease, or schizophrenia. Therefore, neuroimaging of this specific receptor is of significant clinical interest, and it is not surprising that many attempts have been...

  6. Correlating the Metabolic Stability of Psychedelic 5-HT2A Agonists with Anecdotal Reports of Human Oral Bioavailability

    DEFF Research Database (Denmark)

    Leth-Petersen, Sebastian; Bundgaard, Christoffer; Hansen, Martin;

    2014-01-01

    little is known about the relationships between the structure of the ligands and their pharmacokinetic profile. In order to evaluate the potential of these compounds for in vivo applications we have determined the microsomal stability of 11 phenethylamines and 27 N-benzylated derivatives thereof using...... human liver microsomes. We found that the N-benzylated phenethylamines have much higher intrinsic clearance than the parent phenethylamines. We hypothesize that their low hepatic stability renders them orally inactive due to first pass metabolism, which is supported by anecdotal data from recreational...

  7. 5-HT2A and 5-HT2C receptors as hypothalamic targets of developmental programming in male rats

    Science.gov (United States)

    Martin-Gronert, Malgorzata S.; Stocker, Claire J.; Wargent, Edward T.; Cripps, Roselle L.; Garfield, Alastair S.; Jovanovic, Zorica; D'Agostino, Giuseppe; Yeo, Giles S. H.; Cawthorne, Michael A.; Arch, Jonathan R. S.; Heisler, Lora K.; Ozanne, Susan E.

    2016-01-01

    ABSTRACT Although obesity is a global epidemic, the physiological mechanisms involved are not well understood. Recent advances reveal that susceptibility to obesity can be programmed by maternal and neonatal nutrition. Specifically, a maternal low-protein diet during pregnancy causes decreased intrauterine growth, rapid postnatal catch-up growth and an increased risk for diet-induced obesity. Given that the synthesis of the neurotransmitter 5-hydroxytryptamine (5-HT) is nutritionally regulated and 5-HT is a trophic factor, we hypothesised that maternal diet influences fetal 5-HT exposure, which then influences development of the central appetite network and the subsequent efficacy of 5-HT to control energy balance in later life. Consistent with our hypothesis, pregnant rats fed a low-protein diet exhibited elevated serum levels of 5-HT, which was also evident in the placenta and fetal brains at embryonic day 16.5. This increase was associated with reduced levels of 5-HT2CR, the primary 5-HT receptor influencing appetite, in the fetal, neonatal and adult hypothalamus. As expected, a reduction of 5-HT2CR was associated with impaired sensitivity to 5-HT-mediated appetite suppression in adulthood. 5-HT primarily achieves effects on appetite by 5-HT2CR stimulation of pro-opiomelanocortin (POMC) peptides within the arcuate nucleus of the hypothalamus (ARC). We show that 5-HT2ARs are also anatomically positioned to influence the activity of ARC POMC neurons and that mRNA encoding 5-HT2AR is increased in the hypothalamus of in utero growth-restricted offspring that underwent rapid postnatal catch-up growth. Furthermore, these animals at 3 months of age are more sensitive to appetite suppression induced by 5-HT2AR agonists. These findings not only reveal a 5-HT-mediated mechanism underlying the programming of susceptibility to obesity, but also provide a promising means to correct it, by treatment with a 5-HT2AR agonist. PMID:26769798

  8. Acute social defeat does not alter cerebral 5-HT2A receptor binding in male Wistar rats

    NARCIS (Netherlands)

    Visser, Anniek K. D.; Meerlo, Peter; Ettrup, Anders; Knudsen, Gitte M.; Bosker, Fokko J.; den Boer, Johan A.; Dierckx, Rudi A. J. O.; van Waarde, Aren

    2014-01-01

    It has been hypothesized that effects of uncontrollable stress on serotonin receptor expression contribute to the etiology of stress-related disorders like depression. While the serotonin-2A receptors (5-HT2AR) are thought to be important in this context, only few studies examined effects of stress

  9. 5-HT2A Receptor Binding in the Frontal Cortex of Parkinson's Disease Patients and Alpha-Synuclein Overexpressing Mice

    DEFF Research Database (Denmark)

    Rasmussen, Nadja Bredo; Olesen, Mikkel Vestergaard; Brudek, Tomasz;

    2016-01-01

    The receptor is highly involved in aspects of cognition and executive function and seen to be affected in neurodegenerative diseases like Alzheimer’s disease and related to the disease pathology. Even though Parkinson’s disease (PD) is primarily a motor disorder, reports of impaired executive...

  10. Management of skin cancer by agonists of 5-HT1A and antagonists of 5-HT2A receptors

    OpenAIRE

    Menezes, Ana Catarina da Silva Fernandes Saraiva de

    2015-01-01

    Tese de mestrado, Ciências Biofarmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2015 A pele é o maior órgão humano e apresenta funções importantes quer a nível neuroendócrino, quer imunológico. A presença de um análogo do eixo hipotalâmico-hipofisário-adrenal na pele permite reagir a fatores externos de stress e modular as funções da mesma, tais como a melanogénese. A serotonina (5-hidroxitriptamina, 5-HT) é um neuromodelador importante que atua como fator de crescimento no can...

  11. 5-HT2A and 5-HT2C receptors as hypothalamic targets of developmental programming in male rats

    Directory of Open Access Journals (Sweden)

    Malgorzata S. Martin-Gronert

    2016-04-01

    Full Text Available Although obesity is a global epidemic, the physiological mechanisms involved are not well understood. Recent advances reveal that susceptibility to obesity can be programmed by maternal and neonatal nutrition. Specifically, a maternal low-protein diet during pregnancy causes decreased intrauterine growth, rapid postnatal catch-up growth and an increased risk for diet-induced obesity. Given that the synthesis of the neurotransmitter 5-hydroxytryptamine (5-HT is nutritionally regulated and 5-HT is a trophic factor, we hypothesised that maternal diet influences fetal 5-HT exposure, which then influences development of the central appetite network and the subsequent efficacy of 5-HT to control energy balance in later life. Consistent with our hypothesis, pregnant rats fed a low-protein diet exhibited elevated serum levels of 5-HT, which was also evident in the placenta and fetal brains at embryonic day 16.5. This increase was associated with reduced levels of 5-HT2CR, the primary 5-HT receptor influencing appetite, in the fetal, neonatal and adult hypothalamus. As expected, a reduction of 5-HT2CR was associated with impaired sensitivity to 5-HT-mediated appetite suppression in adulthood. 5-HT primarily achieves effects on appetite by 5-HT2CR stimulation of pro-opiomelanocortin (POMC peptides within the arcuate nucleus of the hypothalamus (ARC. We show that 5-HT2ARs are also anatomically positioned to influence the activity of ARC POMC neurons and that mRNA encoding 5-HT2AR is increased in the hypothalamus of in utero growth-restricted offspring that underwent rapid postnatal catch-up growth. Furthermore, these animals at 3 months of age are more sensitive to appetite suppression induced by 5-HT2AR agonists. These findings not only reveal a 5-HT-mediated mechanism underlying the programming of susceptibility to obesity, but also provide a promising means to correct it, by treatment with a 5-HT2AR agonist.

  12. Deficits in LTP induction by 5-HT2A receptor antagonist in a mouse model for fragile X syndrome.

    Directory of Open Access Journals (Sweden)

    Zhao-hui Xu

    Full Text Available Fragile X syndrome is a common inherited form of mental retardation caused by the lack of fragile X mental retardation protein (FMRP because of Fmr1 gene silencing. Serotonin (5-HT is significantly increased in the null mutants of Drosophila Fmr1, and elevated 5-HT brain levels result in cognitive and behavioral deficits in human patients. The serotonin type 2A receptor (5-HT2AR is highly expressed in the cerebral cortex; it acts on pyramidal cells and GABAergic interneurons to modulate cortical functions. 5-HT2AR and FMRP both regulate synaptic plasticity. Therefore, the lack of FMRP may affect serotoninergic activity. In this study, we determined the involvement of FMRP in the 5-HT modulation of synaptic potentiation with the use of primary cortical neuron culture and brain slice recording. Pharmacological inhibition of 5-HT2AR by R-96544 or ketanserin facilitated long-term potentiation (LTP in the anterior cingulate cortex (ACC of WT mice. The prefrontal LTP induction was dependent on the activation of NMDARs and elevation of postsynaptic Ca(2+ concentrations. By contrast, inhibition of 5-HT2AR could not restore the induction of LTP in the ACC of Fmr1 knock-out mice. Furthermore, 5-HT2AR inhibition induced AMPA receptor GluR1 subtype surface insertion in the cultured ACC neurons of Fmr1 WT mice, however, GluR1 surface insertion by inhibition of 5-HT2AR was impaired in the neurons of Fmr1KO mice. These findings suggested that FMRP was involved in serotonin receptor signaling and contributed in GluR1 surface expression induced by 5-HT2AR inactivation.

  13. (11)C-labeling and preliminary evaluation of pimavanserin as a 5-HT2A receptor PET-radioligand

    DEFF Research Database (Denmark)

    Andersen, Valdemar L; Hansen, Hanne D; Herth, Matthias M;

    2015-01-01

    Pimavanserin is a selective serotonin 2A receptor (5-HT2AR) inverse agonist that has shown promise for treatment of psychotic symptoms in patients with Parkinson's disease. Here, we detail the (11)C-labeling and subsequently evaluate pimavanserin as a PET-radioligand in pigs. [(11)C]Pimavanserin....... However, this binding could not be blocked by either ketanserin or pimavanserin itself, indicating high nonspecific binding. The lack of displacement by the 5-HT2R antagonist and binding in the thalamus suggests that [(11)C]pimavanserin is not selective for the 5-HT2AR in pigs....

  14. Growth retardation and altered autonomic control in mice lacking brain serotonin

    OpenAIRE

    Alenina, Natalia; Kikic, Dana; Todiras, Mihail; Mosienko, Valentina; Qadri, Fatimunnisa; Plehm, Ralph; Boyé, Philipp; Vilianovitch, Larissa; Sohr, Reinhard; Tenner, Katja; Hörtnagl, Heide; Bader, Michael

    2009-01-01

    Serotonin synthesis in mammals is initiated by 2 distinct tryptophan hydroxylases (TPH), TPH1 and TPH2. By genetically ablating TPH2, we created mice (Tph2−/−) that lack serotonin in the central nervous system. Surprisingly, these mice can be born and survive until adulthood. However, depletion of serotonin signaling in the brain leads to growth retardation and 50% lethality in the first 4 weeks of postnatal life. Telemetric monitoring revealed more extended daytime sleep, suppressed respirat...

  15. Distinct effect of 5-HT1A and 5-HT2A receptors in the medial nucleus of the amygdala on tonic immobility behavior.

    Science.gov (United States)

    de Paula, Bruna Balbino; Leite-Panissi, Christie Ramos Andrade

    2016-07-15

    The tonic immobility (TI) response is an innate fear behavior associated with intensely dangerous situations, exhibited by many species of invertebrate and vertebrate animals. In humans, it is possible that TI predicts the severity of posttraumatic stress disorder symptoms. This behavioral response is initiated and sustained by the stimulation of various groups of neurons distributed in the telencephalon, diencephalon and brainstem. Previous research has found the highest Fos-IR in the posteroventral part of the medial nucleus of the amygdala (MEA) during TI behavior; however, the neurotransmission of this amygdaloid region involved in the modulation of this innate fear behavior still needs to be clarified. Considering that a major drug class used for the treatment of psychopathology is based on serotonin (5-HT) neurotransmission, we investigated the effects of serotonergic receptor activation in the MEA on the duration of TI. The results indicate that the activation of the 5HT1A receptors or the blocking of the 5HT2 receptors of the MEA can promote a reduction in fear and/or anxiety, consequently decreasing TI duration in guinea pigs. In contrast, blocking the 5HT1A receptors or activating the 5HT2 receptors in this amygdalar region increased the TI duration, suggesting an increase in fear and/or anxiety. These alterations do not appear to be due to a modification of spontaneous motor activity, which might non-specifically affect TI duration. Thus, these results suggest a distinct role of the 5HT receptors in the MEA in innate fear modulation. PMID:27150816

  16. Cerebral 5-HT2A receptor and serotonin transporter binding in humans are not affected by the val66met BDNF polymorphism status or blood BDNF levels

    DEFF Research Database (Denmark)

    Klein, Anders Bue; Trajkovska, Viktorija; Erritzoe, David;

    2010-01-01

    Recent studies have proposed an interrelation between the brain-derived neurotrophic factor (BDNF) val66met polymorphism and the serotonin system. In this study, we investigated whether the BDNF val66met polymorphism or blood BDNF levels are associated with cerebral 5-hydroxytryptamine 2A (5-HT(2...

  17. Ligand-dependent conformations and dynamics of the serotonin 5-HT(2A receptor determine its activation and membrane-driven oligomerization properties.

    Directory of Open Access Journals (Sweden)

    Jufang Shan

    Full Text Available From computational simulations of a serotonin 2A receptor (5-HT(2AR model complexed with pharmacologically and structurally diverse ligands we identify different conformational states and dynamics adopted by the receptor bound to the full agonist 5-HT, the partial agonist LSD, and the inverse agonist Ketanserin. The results from the unbiased all-atom molecular dynamics (MD simulations show that the three ligands affect differently the known GPCR activation elements including the toggle switch at W6.48, the changes in the ionic lock between E6.30 and R3.50 of the DRY motif in TM3, and the dynamics of the NPxxY motif in TM7. The computational results uncover a sequence of steps connecting these experimentally-identified elements of GPCR activation. The differences among the properties of the receptor molecule interacting with the ligands correlate with their distinct pharmacological properties. Combining these results with quantitative analysis of membrane deformation obtained with our new method (Mondal et al, Biophysical Journal 2011, we show that distinct conformational rearrangements produced by the three ligands also elicit different responses in the surrounding membrane. The differential reorganization of the receptor environment is reflected in (i-the involvement of cholesterol in the activation of the 5-HT(2AR, and (ii-different extents and patterns of membrane deformations. These findings are discussed in the context of their likely functional consequences and a predicted mechanism of ligand-specific GPCR oligomerization.

  18. Potentiation of 5-methoxy-N,N-dimethyltryptamine-induced hyperthermia by harmaline and the involvement of activation of 5-HT1A and 5-HT2A receptors

    OpenAIRE

    Jiang, Xi-Ling; Shen, Hong-Wu; Yu, Ai-Ming

    2015-01-01

    5-Methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and harmaline are serotonin (5-HT) analogs often abused together, which alters thermoregulation that may indicate the severity of serotonin toxicity. Our recent studies have revealed that co-administration of monoamine oxidase inhibitor harmaline leads to greater and prolonged exposure to 5-HT agonist 5-MeO-DMT that might be influenced by cytochrome P450 2D6 (CYP2D6) status. This study was to define the effects of harmaline and 5-MeO-DMT on thermor...

  19. 18F-labeling and evaluation of novel MDL 100907 derivatives as potential 5-HT2A antagonists for molecular imaging

    DEFF Research Database (Denmark)

    Debus, Fabian; Herth, Matthias Manfred; Piel, Markus;

    2010-01-01

    no reasonable distribution pattern on autoradiographic sections. Moreover, results from microPET scans of (R)-[(18)F]MH.MZ hint on improved molecular imaging characteristics compared with those of [(18)F]MH.MZ. Therefore, (R)-[(18)F]MH.MZ appears to be a highly potent and selective serotonergic PET ligand...

  20. D-serine deficiency attenuates the behavioral and cellular effects induced by the hallucinogenic 5-HT(2A) receptor agonist DOI

    DEFF Research Database (Denmark)

    Santini, Martin A; Balu, Darrick T; Puhl, Matthew D;

    2014-01-01

    Both the serotonin and glutamate systems have been implicated in the pathophysiology of schizophrenia, as well as in the mechanism of action of antipsychotic drugs. Psychedelic drugs act through the serotonin 2A receptor (5-HT2AR), and elicit a head-twitch response (HTR) in mice, which directly c...

  1. Plaque deposition dependent decrease in 5-HT2A serotonin receptor in AbetaPPswe/PS1dE9 amyloid overexpressing mice

    DEFF Research Database (Denmark)

    Holm, Peter; Ettrup, Anders; Klein, Anders B;

    2010-01-01

    -HT2A receptor regulation in double transgenic AbetaPPswe/PS1dE9 mice which display excess production of Abeta and age-dependent increase in amyloid plaques. Three different age-groups, 4-month-old, 8- month-old, and 11-month-old were included in the study. [3H]-MDL100907, [3H]-escitalopram, and [11C...

  2. Genetic disruption of both tryptophan hydroxylase genes dramatically reduces serotonin and affects behavior in models sensitive to antidepressants.

    Directory of Open Access Journals (Sweden)

    Katerina V Savelieva

    Full Text Available The neurotransmitter serotonin (5-HT plays an important role in both the peripheral and central nervous systems. The biosynthesis of serotonin is regulated by two rate-limiting enzymes, tryptophan hydroxylase-1 and -2 (TPH1 and TPH2. We used a gene-targeting approach to generate mice with selective and complete elimination of the two known TPH isoforms. This resulted in dramatically reduced central 5-HT levels in Tph2 knockout (TPH2KO and Tph1/Tph2 double knockout (DKO mice; and substantially reduced peripheral 5-HT levels in DKO, but not TPH2KO mice. Therefore, differential expression of the two isoforms of TPH was reflected in corresponding depletion of 5-HT content in the brain and periphery. Surprisingly, despite the prominent and evolutionarily ancient role that 5-HT plays in both vertebrate and invertebrate physiology, none of these mutations resulted in an overt phenotype. TPH2KO and DKO mice were viable and normal in appearance. Behavioral alterations in assays with predictive validity for antidepressants were among the very few phenotypes uncovered. These behavioral changes were subtle in the TPH2KO mice; they were enhanced in the DKO mice. Herein, we confirm findings from prior descriptions of TPH1 knockout mice and present the first reported phenotypic evaluations of Tph2 and Tph1/Tph2 knockout mice. The behavioral effects observed in the TPH2 KO and DKO mice strongly confirm the role of 5-HT and its synthetic enzymes in the etiology and treatment of affective disorders.

  3. Risk and protective genetic variants in suicidal behaviour: association with SLC1A2, SLC1A3, 5-HTR1B &NTRK2 polymorphisms

    Directory of Open Access Journals (Sweden)

    Buckley Avril

    2011-06-01

    Full Text Available Abstract Background Suicidal behaviour is known to aggregate in families. Patients with psychiatric disorders are at higher risk for suicide attempts (SA, however protective and risk genetic variants for suicide appear to be independent of underlying psychiatric disorders. Here we investigate genetic variants in genes important for neurobiological pathways linked to suicidal behaviour and/or associated endophenotypes, for association with SA among patients with co-existing psychiatric illness. Selected gene-gene and gene-environment interactions were also tested. Methods DNA was obtained from bloods of 159 patients (76 suicide attempters and 83 non-attempters, who were profiled for DSM-IV Axis I psychiatric diagnosis. Twenty-eight single nucleotide polymorphisms (SNPs from 18 candidate genes (COMT, 5-HT2A, 5-HT1A, 5-HTR1B, TPH1, MAO-A, TPH2, DBH, CNR1, BDNF, ABCG1, GABRA5, GABRG2, GABRB2, SLC1A2, SLC1A3, NTRK2, CRHR1 were genotyped. Genotyping was performed by KBioscience. Tests of association between genetic variants and SA were conducted using Chi squared and Armitage Trend tests. Binary logistical regression analyses were performed to evaluate the contribution of individual genetic variants to the prediction of SA, and to examine SNPs for potential gene-gene and gene-environment interactions. Results Our analysis identified 4 SNPs (rs4755404, rs2269272, rs6296 and rs1659400, which showed evidence of association with SA compared to a non-attempter control group. We provide evidence of a 3-locus gene-gene interaction, and a putative gene-environment interaction, whereby genetic variation at the NTRK2 locus may moderate the risk associated with history of childhood abuse. Conclusion Preliminary findings suggest that allelic variability in SLC1A2/3, 5-HTR1B and NTRK2 may be relevant to the underlying diathesis for suicidal acts.

  4. Risk and protective genetic variants in suicidal behaviour: association with SLC1A2, SLC1A3, 5-HTR1B &NTRK2 polymorphisms.

    LENUS (Irish Health Repository)

    Murphy, Therese M

    2012-02-01

    BACKGROUND: Suicidal behaviour is known to aggregate in families. Patients with psychiatric disorders are at higher risk for suicide attempts (SA), however protective and risk genetic variants for suicide appear to be independent of underlying psychiatric disorders. Here we investigate genetic variants in genes important for neurobiological pathways linked to suicidal behaviour and\\/or associated endophenotypes, for association with SA among patients with co-existing psychiatric illness. Selected gene-gene and gene-environment interactions were also tested. METHODS: DNA was obtained from bloods of 159 patients (76 suicide attempters and 83 non-attempters), who were profiled for DSM-IV Axis I psychiatric diagnosis. Twenty-eight single nucleotide polymorphisms (SNPs) from 18 candidate genes (COMT, 5-HT2A, 5-HT1A, 5-HTR1B, TPH1, MAO-A, TPH2, DBH, CNR1, BDNF, ABCG1, GABRA5, GABRG2, GABRB2, SLC1A2, SLC1A3, NTRK2, CRHR1) were genotyped. Genotyping was performed by KBioscience. Tests of association between genetic variants and SA were conducted using Chi squared and Armitage Trend tests. Binary logistical regression analyses were performed to evaluate the contribution of individual genetic variants to the prediction of SA, and to examine SNPs for potential gene-gene and gene-environment interactions. RESULTS: Our analysis identified 4 SNPs (rs4755404, rs2269272, rs6296 and rs1659400), which showed evidence of association with SA compared to a non-attempter control group. We provide evidence of a 3-locus gene-gene interaction, and a putative gene-environment interaction, whereby genetic variation at the NTRK2 locus may moderate the risk associated with history of childhood abuse. CONCLUSION: Preliminary findings suggest that allelic variability in SLC1A2\\/3, 5-HTR1B and NTRK2 may be relevant to the underlying diathesis for suicidal acts.

  5. Effect of glial cell line-derived neurotrophic factor on behavior and key members of the brain serotonin system in mouse strains genetically predisposed to behavioral disorders.

    Science.gov (United States)

    Naumenko, Vladimir S; Bazovkina, Daria V; Semenova, Alina A; Tsybko, Anton S; Il'chibaeva, Tatyana V; Kondaurova, Elena M; Popova, Nina K

    2013-12-01

    The effect of glial cell line-derived neurotrophic factor (GDNF) on behavior and on the serotonin (5-HT) system of a mouse strain predisposed to depressive-like behavior, ASC/Icg (Antidepressant Sensitive Cataleptics), in comparison with the parental "nondepressive" CBA/Lac mice was studied. Within 7 days after acute administration, GDNF (800 ng, i.c.v.) decreased cataleptic immobility but increased depressive-like behavioral traits in both investigated mouse strains and produced anxiolytic effects in ASC mice. The expression of the gene encoding the key enzyme for 5-HT biosynthesis in the brain, tryptophan hydroxylase-2 (Tph-2), and 5-HT1A receptor gene in the midbrain as well as 5-HT2A receptor gene in the frontal cortex were increased in GDNF-treated ASC mice. At the same time, GDNF decreased 5-HT1A and 5-HT2A receptor gene expression in the hippocampus of ASC mice. GDNF failed to change Tph2, 5-HT1A , or 5-HT2A receptor mRNA levels in CBA mice as well as 5-HT transporter gene expression and 5-HT1A and 5-HT2A receptor functional activity in both investigated mouse strains. The results show 1) a GDNF-induced increase in the expression of key genes of the brain 5-HT system, Tph2, 5-HT1A , and 5-HT2A receptors, and 2) significant genotype-dependent differences in the 5-HT system response to GDNF treatment. The data suggest that genetically defined cross-talk between neurotrophic factors and the brain 5-HT system underlies the variability in behavioral response to GDNF.

  6. Purification and Characterization of Tryptophan Hydroxylase

    DEFF Research Database (Denmark)

    Haahr, Lærke Tvedebrink

    This thesis deals with the purification and characterization of the iron-containing enzyme tryptophan hydroxylase (TPH). TPH exists in two isoforms, called TPH1 and TPH2. Each isoform consists of threestructural distinct domains: the regulatory, the catalytic and the tetramerization domain. TPH c...

  7. [18F]Altanserin and small animal PET: Impact of multidrug efflux transporters on ligand brain uptake and subsequent quantification of 5-HT2A receptor densities in the rat brain

    International Nuclear Information System (INIS)

    Introduction: The selective 5-hydroxytryptamine type 2a receptor (5-HT2AR) radiotracer [18F]altanserin is a promising ligand for in vivo brain imaging in rodents. However, [18F]altanserin is a substrate of P-glycoprotein (P-gp) in rats. Its applicability might therefore be constrained by both a differential expression of P-gp under pathological conditions, e.g. epilepsy, and its relatively low cerebral uptake. The aim of the present study was therefore twofold: (i) to investigate whether inhibition of multidrug transporters (MDT) is suitable to enhance the cerebral uptake of [18F]altanserin in vivo and (ii) to test different pharmacokinetic, particularly reference tissue-based models for exact quantification of 5-HT2AR densities in the rat brain. Methods: Eighteen Sprague-Dawley rats, either treated with the MDT inhibitor cyclosporine A (CsA, 50 mg/kg, n = 8) or vehicle (n = 10) underwent 180-min PET scans with arterial blood sampling. Kinetic analyses of tissue time–activity curves (TACs) were performed to validate invasive and non-invasive pharmacokinetic models. Results: CsA application lead to a two- to threefold increase of [18F]altanserin uptake in different brain regions and showed a trend toward higher binding potentials (BPND) of the radioligand. Conclusions: MDT inhibition led to an increased cerebral uptake of [18F]altanserin but did not improve the reliability of BPND as a non-invasive estimate of 5-HT2AR. This finding is most probable caused by the heterogeneous distribution of P-gp in the rat brain and its incomplete blockade in the reference region (cerebellum). Differential MDT expressions in experimental animal models or pathological conditions are therefore likely to influence the applicability of imaging protocols and have to be carefully evaluated

  8. The role of dopamine D3, 5-HT2A and 5-HT2C receptor variants as pharmacogenetic determinants in tardive dyskinesia in African-Caribbean patients under chronic antipsychotic treatment

    NARCIS (Netherlands)

    Wilffert, B.; Al Hadithy, A.F.; Sing, V.J.; Matroos, G.; Hoek, H.W.; van Os, J.; Bruggeman, R.; Brouwers, J.R.; van Harten, P.N.

    2009-01-01

    Abstract Tardive dyskinesia (TD) is associated with polymorphisms of the dopamine D3, serotonin 2A and 2C receptors (DRD3, HTR2A and HTR2C, respectively). This study investigated the possible relationship between TD and the polymorphisms Ser9Gly (DRD3), 102T>C (HTR2A), -1438G>A(HTR2A) and Cys23Ser (

  9. The role of dopamine D-3, 5-HT2(A) and 5-HT2(C) receptor variants as pharmacogenetic determinants in tardive dyskinesia in African-Caribbean patients under chronic antipsychotic treatment Curacao extrapyramidal syndromes study IX

    NARCIS (Netherlands)

    Wilffert, B.; Al Hadithy, A. F. Y.; Sing, V. J.; Matroos, G.; Hoek, H. W.; van Os, J.; Bruggeman, R.; Brouwers, J. R. B. J.; van Harten, P. N.

    2009-01-01

    Tardive dyskinesia (TD) is associated with polymorphisms of the dopamine D-3, serotonin 2A and 2C receptors (DRD3, HTR2A and HTR2C, respectively). This study investigated the possible relationship between TD and the polymorphisms Ser9Gly (DRD3), 102T>C (HTR2A), -1438G>A(HTR2A) and Cys23Ser (HTR2C) i

  10. TPH2 G/T Polymorphism Is Associated with Hyperphagia, IQ, and Internalizing Problems in Prader-Willi Syndrome

    Science.gov (United States)

    Dykens, Elisabeth M.; Roof, Elizabeth; Bittel, Douglas; Butler, Merlin G.

    2011-01-01

    Background: Prader-Willi syndrome (PWS) is a genetic, neurodevelopmental disorder characterized by intellectual disabilities, growth hormone dysregulation, hyperphagia, increased risks of morbid obesity, compulsive behaviors, and irritability. As aberrant serotonergic functioning is strongly implicated in PWS, we examined associations between the…

  11. Design, Synthesis, and Pharmacological Characterization of N- and O-Substituted 5,6,7,8-Tetrahydro-4H-isoxazolo[4,5-d]azepin-3-ol Analogues: Novel 5-HT2A/5-HT2C Receptor Agonists with Pro-Cognitive Properties

    DEFF Research Database (Denmark)

    Jensen, Anders A.; Plath, Niels; Pedersen, Martin Holst Friborg;

    2013-01-01

    to be selective for the two receptors. Administration of 3d substantially improved the cognitive performance of mice in a place recognition Y-maze model, an effect fully reversible by coadministration of the selective 5-HT2C antagonist SB242084. In conclusion, as novel bioavailable cognitive enhancers that most...

  12. Expressivity of tocopherol mutations in sunflower

    OpenAIRE

    Demurin Ya.N.; Efimenko S. G.; Peretyagina T.M.

    2006-01-01

    Influences of genetic background, ontogenesis and environment on tocopherol mutations in sunflower were estimated in this study. The content of α/β - tocopherols varied from 40/60 to 60/40% in seeds of different inbred lines containing the tph1 gene. The lines containing the tph2 gene ranged widely in α/γ - tocopherols, from 0/100 to 80/20%. A double mutation showed variability in different inbred lines in α/β/γ/δ-tocopherol contents from maximum expressivity of 0/0/60/40 to minimum 40/25/25/...

  13. The tryptophan hydroxylase 1 (TPH1) gene, schizophrenia susceptibility, and suicidal behavior: a multi-centre case-control study and meta-analysis

    DEFF Research Database (Denmark)

    Saetre, Peter; Lundmark, Per; Wang, August;

    2010-01-01

    associated with schizophrenia. The minor allele (A) of this polymorphism (A218C) is also more frequent in patients who have attempted suicide and individuals who died by suicide, than in healthy control individuals. In an attempt to replicate previous findings, five single nucleotide polymorphisms (SNPs....../A779 locus increases the susceptibility of schizophrenia in Caucasian and Asian populations. In addition, the data at hand suggest that the locus contributes to the liability of psychiatric disorders characterized by elevated suicidal rates, rather than affecting suicidal behavior of individuals...

  14. The Influence of Family Structure, the TPH2 G-703T and the 5-HTTLPR Serotonergic Genes upon Affective Problems in Children Aged 10-14 Years

    Science.gov (United States)

    Nobile, Maria; Rusconi, Marianna; Bellina, Monica; Marino, Cecilia; Giorda, Roberto; Carlet, Ombretta; Vanzin, Laura; Molteni, Massimo; Battaglia, Marco

    2009-01-01

    Background: Both genetic and psychosocial risk factors influence the risk for depression in development. While the impacts of family structure and of serotonergic polymorphisms upon individual differences for affective problems have been investigated separately, they have never been considered together in a gene-environment interplay perspective.…

  15. Effect of long-term actual spaceflight on the expression of key genes encoding serotonin and dopamine system

    Science.gov (United States)

    Popova, Nina; Shenkman, Boris; Naumenko, Vladimir; Kulikov, Alexander; Kondaurova, Elena; Tsybko, Anton; Kulikova, Elisabeth; Krasnov, I. B.; Bazhenova, Ekaterina; Sinyakova, Nadezhda

    The effect of long-term spaceflight on the central nervous system represents important but yet undeveloped problem. The aim of our work was to study the effect of 30-days spaceflight of mice on Russian biosatellite BION-M1 on the expression in the brain regions of key genes of a) serotonin (5-HT) system (main enzymes in 5-HT metabolism - tryptophan hydroxylase-2 (TPH-2), monoamine oxydase A (MAO A), 5-HT1A, 5-HT2A and 5-HT3 receptors); b) pivotal enzymes in DA metabolism (tyrosine hydroxylase, COMT, MAO A, MAO B) and D1, D2 receptors. Decreased expression of genes encoding the 5-HT catabolism (MAO A) and 5-HT2A receptor in some brain regions was shown. There were no differences between “spaceflight” and control mice in the expression of TPH-2 and 5-HT1A, 5-HT3 receptor genes. Significant changes were found in genetic control of DA system. Long-term spaceflight decreased the expression of genes encoding the enzyme in DA synthesis (tyrosine hydroxylase in s.nigra), DA metabolism (MAO B in the midbrain and COMT in the striatum), and D1 receptor in hypothalamus. These data suggested that 1) microgravity affected genetic control of 5-HT and especially the nigrostriatal DA system implicated in the central regulation of muscular tonus and movement, 2) the decrease in the expression of genes encoding key enzyme in DA synthesis, DA degradation and D1 receptor contributes to the movement impairment and dyskinesia produced by the spaceflight. The study was supported by Russian Foundation for Basic Research grant № 14-04-00173.

  16. Glucocorticoids Inhibit Basal and Hormone-Induced Serotonin Synthesis in Pancreatic Beta Cells

    Science.gov (United States)

    Hasni Ebou, Moina; Singh-Estivalet, Amrit; Launay, Jean-Marie; Callebert, Jacques; Tronche, François; Ferré, Pascal; Gautier, Jean-François; Guillemain, Ghislaine; Bréant, Bernadette

    2016-01-01

    Diabetes is a major complication of chronic Glucocorticoids (GCs) treatment. GCs induce insulin resistance and also inhibit insulin secretion from pancreatic beta cells. Yet, a full understanding of this negative regulation remains to be deciphered. In the present study, we investigated whether GCs could inhibit serotonin synthesis in beta cell since this neurotransmitter has been shown to be involved in the regulation of insulin secretion. To this aim, serotonin synthesis was evaluated in vitro after treatment with GCs of either islets from CD1 mice or MIN6 cells, a beta-cell line. We also explored the effect of GCs on the stimulation of serotonin synthesis by several hormones such as prolactin and GLP 1. We finally studied this regulation in islet in two in vivo models: mice treated with GCs and with liraglutide, a GLP1 analog, and mice deleted for the glucocorticoid receptor in the pancreas. We showed in isolated islets and MIN6 cells that GCs decreased expression and activity of the two key enzymes of serotonin synthesis, Tryptophan Hydroxylase 1 (Tph1) and 2 (Tph2), leading to reduced serotonin contents. GCs also blocked the induction of serotonin synthesis by prolactin or by a previously unknown serotonin activator, the GLP-1 analog exendin-4. In vivo, activation of the Glucagon-like-Peptide-1 receptor with liraglutide during 4 weeks increased islet serotonin contents and GCs treatment prevented this increase. Finally, islets from mice deleted for the GR in the pancreas displayed an increased expression of Tph1 and Tph2 and a strong increased serotonin content per islet. In conclusion, our results demonstrate an original inhibition of serotonin synthesis by GCs, both in basal condition and after stimulation by prolactin or activators of the GLP-1 receptor. This regulation may contribute to the deleterious effects of GCs on beta cells. PMID:26901633

  17. Glucocorticoids Inhibit Basal and Hormone-Induced Serotonin Synthesis in Pancreatic Beta Cells.

    Directory of Open Access Journals (Sweden)

    Moina Hasni Ebou

    Full Text Available Diabetes is a major complication of chronic Glucocorticoids (GCs treatment. GCs induce insulin resistance and also inhibit insulin secretion from pancreatic beta cells. Yet, a full understanding of this negative regulation remains to be deciphered. In the present study, we investigated whether GCs could inhibit serotonin synthesis in beta cell since this neurotransmitter has been shown to be involved in the regulation of insulin secretion. To this aim, serotonin synthesis was evaluated in vitro after treatment with GCs of either islets from CD1 mice or MIN6 cells, a beta-cell line. We also explored the effect of GCs on the stimulation of serotonin synthesis by several hormones such as prolactin and GLP 1. We finally studied this regulation in islet in two in vivo models: mice treated with GCs and with liraglutide, a GLP1 analog, and mice deleted for the glucocorticoid receptor in the pancreas. We showed in isolated islets and MIN6 cells that GCs decreased expression and activity of the two key enzymes of serotonin synthesis, Tryptophan Hydroxylase 1 (Tph1 and 2 (Tph2, leading to reduced serotonin contents. GCs also blocked the induction of serotonin synthesis by prolactin or by a previously unknown serotonin activator, the GLP-1 analog exendin-4. In vivo, activation of the Glucagon-like-Peptide-1 receptor with liraglutide during 4 weeks increased islet serotonin contents and GCs treatment prevented this increase. Finally, islets from mice deleted for the GR in the pancreas displayed an increased expression of Tph1 and Tph2 and a strong increased serotonin content per islet. In conclusion, our results demonstrate an original inhibition of serotonin synthesis by GCs, both in basal condition and after stimulation by prolactin or activators of the GLP-1 receptor. This regulation may contribute to the deleterious effects of GCs on beta cells.

  18. Selective estrogen receptor-beta (SERM-beta) compounds modulate raphe nuclei tryptophan hydroxylase-1 (TPH-1) mRNA expression and cause antidepressant-like effects in the forced swim test.

    Science.gov (United States)

    Clark, J A; Alves, S; Gundlah, C; Rocha, B; Birzin, E T; Cai, S-J; Flick, R; Hayes, E; Ho, K; Warrier, S; Pai, L; Yudkovitz, J; Fleischer, R; Colwell, L; Li, S; Wilkinson, H; Schaeffer, J; Wilkening, R; Mattingly, E; Hammond, M; Rohrer, S P

    2012-11-01

    Estrogen acts through two molecularly distinct receptors termed estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) which bind estradiol with similar affinities and mediate the effects of estrogen throughout the body. ERα plays a major role in reproductive physiology and behavior, and mediates classic estrogen signaling in such tissues as the uterus, mammary gland, and skeleton. ERβ, however, modulates estrogen signaling in the ovary, the immune system, prostate, gastrointestinal tract, and hypothalamus, and there is some evidence that ERβ can regulate ERα activity. Moreover, ERβ knockout studies and receptor distribution analyses in the CNS suggest that this receptor may play a role in the modulation of mood and cognition. In recent years several ERβ-specific compounds (selective estrogen receptor beta modulators; SERM-beta) have become available, and research suggests potential utility of these compounds in menopausal symptom relief, breast cancer prevention, diseases that have an inflammatory component, osteoporosis, cardiovascular disease, and inflammatory bowel disease, as well as modulation of mood, and anxiety. Here we demonstrate an antidepressant-like effect obtained using two SERM-beta compounds, SERM-beta1 and SERM-beta2. These compounds exhibit full agonist activity at ERβ in a cell based estrogen response element (ERE) transactivation assay. SERM-beta1 and 2 are non-proliferative with respect to breast as determined using the MCF-7 breast cancer cell-based assay and non-proliferative in the uterus as determined by assessing the effects of SERM-beta compounds on immature rat uterine weight and murine uterine weight. In vivo SERM-beta1 and 2 are brain penetrant and display dose dependent efficacy in the murine dorsal raphe assays for induction of tryptophan hydroxylase mRNA and progesterone receptor protein. These compounds show activity in the murine forced swim test and promote hippocampal neurogenesis acutely in rats. Taken together these data suggest that ERβ may play an important role in modulating mood and the ERβ specific compounds described herein will be useful tools for probing the utility of an ERβ agonist for treating neuroendocrine-related mood disturbance and menopausal symptoms.

  19. Reduced nursing frequency during prolonged lactation in the mouse decreases milk production and increases mammary expression of tryptophan hydroxylase 1 (TPH1), but does not accelerate mammary gland remodeling

    Science.gov (United States)

    We have observed that lactating mouse dams nursed 4 times per day (4X) maintained lactation, but had lower milk yields by the weigh-suckle-weigh method, than dams nursed ad libitum (AL). Therefore, we hypothesized that decreased nursing frequency would also decrease lactation persistence, increase m...

  20. Radiosynthesis and evaluation of 11C-CIMBI-5 as a 5-HT2A receptor agonist radioligand for PET

    DEFF Research Database (Denmark)

    Ettrup, Anders; Palner, Mikael; Gillings, Nic;

    2010-01-01

    PET brain imaging of the serotonin 2A (5-hydroxytryptamine 2A, or 5-HT(2A)) receptor has been widely used in clinical studies, and currently, several well-validated radiolabeled antagonist tracers are used for in vivo imaging of the cerebral 5-HT(2A) receptor. Access to 5-HT(2A) receptor agonist ...

  1. Radiosynthesis and in vivo evaluation of a series of substituted 11C-phenethylamines as 5-HT2A agonist PET tracers

    DEFF Research Database (Denmark)

    Ettrup, Anders; Hansen, Martin; Santini, Martin A;

    2011-01-01

    Positron emission tomography (PET) imaging of serotonin 2A (5-HT(2A)) receptors with agonist tracers holds promise for the selective labelling of 5-HT(2A) receptors in their high-affinity state. We have previously validated [(11)C]Cimbi-5 and found that it is a 5-HT(2A) receptor agonist PET trace...

  2. Enhanced prefrontal serotonin 2A receptor signaling in the subchronic phencyclidine mouse model of schizophrenia

    DEFF Research Database (Denmark)

    Santini, Martin A; Ratner, Cecilia Friis; Aznar, Susana;

    2013-01-01

    Prefrontal serotonin 2A receptors (5-HT2A Rs) have been linked to the pathogenesis and treatment of schizophrenia. Many antipsychotics fully occupy 5-HT2A R at clinical relevant doses, and activation of 5-HT2A receptors by lysergic acid diethylamide (LSD) and LSD-like drugs induces a schizophrenia...

  3. Genetic possibilities for altering sunflower oil quality to obtain novel oils.

    Science.gov (United States)

    Skorić, Dragan; Jocić, Sinisa; Sakac, Zvonimir; Lecić, Nada

    2008-04-01

    The sunflower is one of the four most important oilseed crops in the world, and the nutritional quality of its edible oil ranks among the best vegetable oils in cultivation. Typically up to 90% of the fatty acids in conventional sunflower oil are unsaturated, namely oleic (C 18:1, 16%-19%) and linoleic (C 18:2, 68%-72%) fatty acids. Palmitic (C 16:0, 6%), stearic (C 18:0, 5%), and minor amounts of myristic (C 14:0), myristoleic (C 14:1), palmitoleic (C 16:1), arachidic (C 20:0), behenic (C 22:0), and other fatty acids account for the remaining 10%. Advances in modern genetics, most importantly induced mutations, have altered the fatty acid composition of sunflower oil to a significant extent. Treating sunflower seeds with gamma- and X-rays has produced mutants with 25%-30% palmitic acid. Sunflower seed treatment with X-rays has also resulted in mutants having 30% palmitoleic acid, while treatments with mutagenic sodium azide have produced seeds containing 35% stearic acid. The most important mutations have been obtained by treatment with dimethyl sulfate, which produced genotypes with more than 90% oleic acid. Mutants have also been obtained that have a high linoleic acid content (>80%) by treating seeds with X-rays and ethyl methanesulfonate. Of the vitamin E family of compounds, sunflower oil is known to predominantly contain alpha-tocopherol (>90%). Spontaneous mutations controlled by recessive genes have been discovered that significantly alter tocopherol forms and levels. The genes in question are tph(1) (50% alpha- and 50% beta-tocopherol), tph(2) (0%-5% alpha- and 95%-100% gamma-tocopherol), and tph(1)tph(2) (8%-40% alpha-, 0%-25% beta-, 25%-84% gamma-, and 8%-50% delta-tocopherol). The existence of (mutant) genes for increased levels of individual fatty acids and for different forms and levels of tocopherol enables the development of sunflower hybrids with different oil quality. The greatest progress has been made in developing high-oleic hybrids (>90

  4. The role of the serotonergic system in suicidal behavior

    Directory of Open Access Journals (Sweden)

    Sadkowski M

    2013-11-01

    Full Text Available Marta Sadkowski,1,* Brittany Dennis,2–4,* Robert C Clayden,2 Wala ElSheikh,5 Sumathy Rangarajan,5 Jane DeJesus,5 Zainab Samaan3–6 1Arts and Sciences Program, 2Faculty of Health Sciences, 3Department of Clinical Epidemiology and Biostatistics, 4Population Genomics Program, McMaster University, Hamilton, ON, Canada; 5Population Health Research Institute, Hamilton, ON, Canada; 6Department of Psychiatry and Behavioral Neurosciences, McMaster University, Hamilton, ON, Canada *These authors contributed equally to this work Abstract: Serotonin is a widely investigated neurotransmitter in several psychopathologies, including suicidal behavior (SB; however, its role extends to several physiological functions involving the nervous system, as well as the gastrointestinal and cardiovascular systems. This review summarizes recent research into ten serotonergic genes related to SB. These genes – TPH1, TPH2, SLC6A4, SLC18A2, HTR1A, HTR1B, HTR2A, DDC, MAOA, and MAOB – encode proteins that are vital to serotonergic function: tryptophan hydroxylase; the serotonin transporter 5-HTT; the vesicular transporter VMAT2; the HTR1A, HTR1B, and HTR2A receptors; the L-amino acid decarboxylase; and the monoamine oxidases. This review employed a systematic search strategy and a narrative research methodology to disseminate the current literature investigating the link between SB and serotonin. Keywords: serotonin, suicide, genetic

  5. Improving effect of chronic resveratrol treatment on central monoamine synthesis and cognition in aged rats.

    Science.gov (United States)

    Sarubbo, F; Ramis, M R; Aparicio, S; Ruiz, L; Esteban, S; Miralles, A; Moranta, D

    2015-06-01

    Resveratrol is a polyphenol exhibiting antioxidant and neuroprotective effects in neurodegenerative diseases. However, neuroprotective properties during normal aging have not been clearly demonstrated. We analyzed the in vivo effects of chronic administration of resveratrol (20 mg/kg/day for 4 weeks) in old male rats (Wistar, 20 months), on tryptophan hydroxylase (TPH) and tyrosine hydroxylase (TH) activities which mediate central monoaminergic neurotransmitters synthesis, and besides, on hippocampal-dependent working memory test (radial maze). Our results show an age-related decline in neurochemical parameters that were reversed by resveratrol administration. The resveratrol treatment enhances serotonin (5-HT) levels in pineal gland, in hippocampus, and in striatum, and those of noradrenaline (NA) in hippocampus and also dopamine (DA) in striatum. These changes were largely due to an increased activity of TPH-1 (463 % in pineal gland), TPH-2 (70-51 % in hippocampus and striatum), and TH (150-36 % in hippocampus and striatum). Additionally, the observed hippocampal effects correlate with a resveratrol-induced restorative effect on working memory (radial maze). In conclusion, this study suggests resveratrol treatment as a restoring therapy for the impaired cognitive functions occurring along normal aging process, by preventing 5-HT, DA, and NA neurotransmission decline.

  6. Sexually dimorphic serotonergic dysfunction in a mouse model of Huntington's disease and depression.

    Directory of Open Access Journals (Sweden)

    Thibault Renoir

    Full Text Available Depression is the most common psychiatric disorder in Huntington's disease (HD patients. In the general population, women are more prone to develop depression and such susceptibility might be related to serotonergic dysregulation. There is yet to be a study of sexual dimorphism in the development and presentation of depression in HD patients. We investigated whether 8-week-old male and female R6/1 transgenic HD mice display depressive-like endophenotypes associated with serotonergic impairments. We also studied the behavioral effects of acute treatment with sertraline. We found that only female HD mice exhibited a decreased preference for saccharin as well as impaired emotionality-related behaviors when assessed on the novelty-suppressed feeding test (NSFT and the forced-swimming test (FST. The exaggerated immobility time displayed by female HD in the FST was reduced by acute administration of sertraline. We also report an increased response to the 5-HT(1A receptor agonist 8-OH-DPAT in inducing hypothermia and a decreased 5-HT(2A receptor function in HD animals. While tissue levels of serotonin were reduced in both male and female HD mice, we found that serotonin concentration and hydroxylase-2 (TPH2 mRNA levels were higher in the hippocampus of males compared to female animals. Finally, the antidepressant-like effects of sertraline in the FST were blunted in male HD animals. This study reveals sex-specific depressive-related behaviors during an early stage of HD prior to any cognitive and motor deficits. Our data suggest a crucial role for disrupted serotonin signaling in mediating the sexually dimorphic depression-like phenotype in HD mice.

  7. Transcriptional up-regulation in expression of 5-hydroxytryptamine2A and transcriptional down-regulation of angiotensin II type 1 receptors during organ culture of rat mesenteric artery

    DEFF Research Database (Denmark)

    Luo, Guogang; Xu, Cang-Bao; Cao, Yong-Xiao;

    2004-01-01

    receptors (5-HT(2A)) and angiotensin II type 1 receptors (AT(1)) demonstrated that the contractions occurred via 5-HT(2A) and AT(1) receptors, respectively. Real-time PCR revealed that the 5-HT(2A) receptor mRNA was up-regulated in parallel with the contractile response while there was a down-regulation of...... AT(1) receptor mRNA. Transcriptional inhibitor actinomycin D and specific protein kinase C inhibitor Ro31-8220 demonstrated that it was a transcriptional mechanism with involvement of protein kinase C that regulated the enhanced expression of 5-HT(2A) receptors in the mesenteric artery....

  8. Novelty-induced activity-regulated cytoskeletal-associated protein (Arc) expression in frontal cortex requires serotonin 2A receptor activation

    DEFF Research Database (Denmark)

    Santini, Martin; Klein, A B; El-Sayed, M;

    2011-01-01

    , indicating that the involvement of 5-HT(2A)R in this response is restricted to the FC. Similarly, the novelty-induced stress as determined by increasing levels of plasma corticosterone, was not influenced by 5-HT(2A)R antagonism suggesting that Arc mRNA and stress are activated via distinct mechanisms. Taken...

  9. Serotonin 2A receptor antagonists for treatment of schizophrenia

    DEFF Research Database (Denmark)

    Ebdrup, Bjørn Hylsebeck; Rasmussen, Hans; Arnt, Jørn;

    2011-01-01

    receptor antagonists is evaluated. Moreover, the investigational pipeline of major pharmaceutical companies is examined and an Internet search conducted to identify other pharmaceutical companies investigating 5-HT2A receptor antagonists for the treatment of schizophrenia. Expert opinion: 5-HT2A receptor...

  10. Serotonin 2A receptors contribute to the regulation of risk-averse decisions

    DEFF Research Database (Denmark)

    Macoveanu, Julian; Rowe, James B; Hornboll, Bettina;

    2013-01-01

    in processing negative outcomes and regulating risk-averse behavior. During fMRI, twenty healthy volunteers performed a gambling task under two conditions: with or without blocking the 5-HT2A receptors. The volunteers repeatedly chose between small, likely rewards and large, unlikely rewards. Choices were...... with large missed rewards. In the context of normal 5-HT2A receptor function, ventral striatum displayed a stronger response to low-risk negative outcomes in risk-taking as opposed to risk-averse individuals. This (negative) correlation between the striatal response to low-risk negative outcomes and risk......-averse choice behavior was abolished by 5-HT2A receptor blockade. The results provide the first evidence for a critical role of 5-HT2A receptor function in regulating risk-averse behavior. We suggest that the 5-HT2A receptor system facilitates risk-taking behavior by modulating the outcome evaluation of "missed...

  11. Transgenic expression of the human growth hormone minigene promotes pancreatic β-cell proliferation.

    Science.gov (United States)

    Baan, Mieke; Kibbe, Carly R; Bushkofsky, Justin R; Harris, Ted W; Sherman, Dawn S; Davis, Dawn Belt

    2015-10-01

    Transgenic mouse models are designed to study the role of specific proteins. To increase transgene expression the human growth hormone (hGH) minigene, including introns, has been included in many transgenic constructs. Until recently, it was thought that the hGH gene was not spliced, transcribed, and translated to produce functional hGH protein. We generated a transgenic mouse with the transcription factor Forkhead box M1 (FoxM1) followed by the hGH minigene, under control of the mouse insulin promoter (MIP) to target expression specifically in the pancreatic β-cell. Expression of FoxM1 in isolated pancreatic islets in vitro stimulates β-cell proliferation. We aimed to investigate the effect of FoxM1 on β-cell mass in a mouse model for diabetes mellitus. However, we found inadvertent coexpression of hGH protein from a spliced, bicistronic mRNA. MIP-FoxM1-hGH mice had lower blood glucose and higher pancreatic insulin content, due to increased β-cell proliferation. hGH signals through the murine prolactin receptor, and expression of its downstream targets tryptophan hydroxylase-1 (Tph1), tryptophan hydroxylase-2 (Tph2), and cytokine-inducible SH2 containing protein (Cish) was increased. Conversely, transcriptional targets of FoxM1 were not upregulated. Our data suggest that the phenotype of MIP-FoxM1-hGH mice is due primarily to hGH activity and that the FoxM1 protein remains largely inactive. Over the past decades, multiple transgenic mouse strains were generated that make use of the hGH minigene to increase transgene expression. Our work suggests that each will need to be carefully screened for inadvertent hGH production and critically evaluated for the use of proper controls. PMID:26202070

  12. 前额叶皮层的5-HT谷氨酸:一个新的抗精神病药的靶点%5-HT in prefrontal cortex:a new target of psychotolytic drugs

    Institute of Scientific and Technical Information of China (English)

    张策

    2000-01-01

    Activation of neocortical 5 hydroxytryptamine 2A (5-HT2A) re ceptors is thought to mediate the profoud psychominetic effects of hallucinogeni c drugs such as lysergic acid diethylamide(LSD).Coversely, blockade of neocortic al 5-HT2A receptor may be related to the thymoleptic effects of newly rele ased antidepressant especially atypical antipsychotic drugs. Electrophsiological experiments using in vitro rat slices of the medial prefrontal cortex has f ound that activation of 5-HT2A receptors results in glutamate release fr om thalamocortical terminals.In addition to activation of 5-HT2A receptors , metabotropic glutamate (mGluR),and neuropeptide (μ-opioid) receptors suppress this release of glutamate that is induced by 5-HT2A receptor activation. Recent clinical reports have found clear structural change in the prefrontal cor tex of depressed patients. Furthermore, a number of post-mortem studies of suici des from different laboratories have found an increased number of 5-HT2A b inding sites in certain regions of the prefrontal cortex. Thus,understanding the effects of 5-HT2A receptor activation in prefrontal cortex is likely to b e relevant for the development of antidepressant drugs.

  13. Loss of serotonin 2A receptors exceeds loss of serotonergic projections in early Alzheimer's disease

    DEFF Research Database (Denmark)

    Marner, Lisbeth; Frøkjær, Vibe; Kalbitzer, Jan;

    2012-01-01

    In patients with Alzheimer's disease (AD), postmortem and imaging studies have revealed early and prominent reductions in cerebral serotonin 2A (5-HT(2A)) receptors. To establish if this was due to a selective disease process of the serotonin system, we investigated the cerebral 5-HT(2A) receptor...... = .0005). No change in [(11)C]DASB binding was found in the midbrain. We conclude that the prominent reduction in neocortical 5-HT(2A) receptor binding in early AD is not caused by a primary loss of serotonergic neurons or their projections....

  14. HSV-Mediated Transgene Expression of Chimeric Constructs to Study Behavioral Function of GPCR Heteromers in Mice.

    Science.gov (United States)

    Holloway, Terrell; Moreno, Jose L; González-Maeso, Javier

    2016-01-01

    The heteromeric receptor complex between 5-HT2A and mGlu2 has been implicated in some of the behavioral phenotypes in mouse models of psychosis(1,2). Consequently, investigation of structural details of the interaction between 5-HT2A and mGlu2 affecting schizophrenia-related behaviors represents a powerful translational tool. As previously shown, the head-twitch response (HTR) in mice is elicited by hallucinogenic drugs and this behavioral response is absent in 5-HT2A knockout (KO) mice(3,4). Additionally, by conditionally expressing the 5-HT2A receptor only in cortex, it was demonstrated that 5-HT2A receptor-dependent signaling pathways on cortical pyramidal neurons are sufficient to elicit head-twitch behavior in response to hallucinogenic drugs(3). Finally, it has been shown that the head-twitch behavioral response induced by the hallucinogens DOI and lysergic acid diethylamide (LSD) is significantly decreased in mGlu2-KO mice(5). These findings suggest that mGlu2 is at least in part necessary for the 5-HT2A receptor-dependent psychosis-like behavioral effects induced by LSD-like drugs. However, this does not provide evidence as to whether the 5-HT2A-mGlu2 receptor complex is necessary for this behavioral phenotype. To address this question, herpes simplex virus (HSV) constructs to express either mGlu2 or mGlu2ΔTM4N (mGlu2/mGlu3 chimeric construct that does not form the 5-HT2A-mGlu2 receptor complex) in the frontal cortex of mGlu2-KO mice were used to examine whether this GPCR heteromeric complex is needed for the behavioral effects induced by LSD-like drugs(6). PMID:27501227

  15. Serotonin 2a Receptor and serotonin 1a receptor interact within the medial prefrontal cortex during recognition memory in mice

    Directory of Open Access Journals (Sweden)

    Juan Facundo Morici

    2015-12-01

    Full Text Available Episodic memory, can be defined as the memory for unique events. The serotonergic system one of the main neuromodulatory systems in the brain appears to play a role in it. The serotonin 2a receptor (5-HT2aR one of the principal post-synaptic receptors for 5-HT in the brain, is involved in neuropsychiatric and neurological disorders associated with memory deficits. Recognition memory can be defined as the ability to recognize if a particular event or item was previously encountered and is thus considered, under certain conditions, a form of episodic memory. As human data suggest that a constitutively decrease of 5-HT2A signaling might affect episodic memory performance we decided to compare the performance of mice with disrupted 5-HT2aR signaling (htr2a -/- with wild type (htr2a+/+ littermates in different recognition memory and working memory tasks that differed in the level of proactive interference. We found that ablation of 5-HT2aR signaling throughout development produces a deficit in tasks that cannot be solved by single item strategy suggesting that 5-HT2aR signaling is involved in interference resolution. We also found that in the absence of 5-HT2aR signaling serotonin has a deleterious effect on recognition memory retrieval through the activation of 5-HT1aR in the medial prefrontal cortex.

  16. Mechanism of Inhibition of Novel Tryptophan Hydroxylase Inhibitors Revealed by Co-crystal Structures and Kinetic Analysis

    OpenAIRE

    Cianchetta, Giovanni; Stouch, Terry; Yu, Wangsheng; Shi, Zhi-cai; Tari, Leslie W.; Swanson, Ronald V.; Hunter, Michael J; Hoffman, Isaac D.; Liu, QingYun

    2010-01-01

    Trytophan Hydroxylase Type I (TPH1), most abundantly expressed in the gastrointestinal tract, initiates the synthesis of serotonin by catalyzing hydroxylation of tryptophan in the presence of biopterin and oxygen. We have previously described three series of novel, periphery-specific TPH1 inhibitors that selectively deplete serotonin in the gastrointestinal tract. We have now determined co-crystal structures of TPH1 with three of these inhibitors at high resolution. Analysis of the structural...

  17. 5-HT2 receptors modulate the expression of antipsychotic-induced dopamine supersensitivity.

    Science.gov (United States)

    Charron, Alexandra; Hage, Cynthia El; Servonnet, Alice; Samaha, Anne-Noël

    2015-12-01

    Antipsychotic treatment can produce supersensitivity to dopamine receptor stimulation. This compromises the efficacy of ongoing treatment and increases the risk of relapse to psychosis upon treatment cessation. Serotonin 5-HT2 receptors modulate dopamine function and thereby influence dopamine-dependent responses. Here we evaluated the hypothesis that 5-HT2 receptors modulate the behavioural expression of antipsychotic-induced dopamine supersensitivity. To this end, we first treated rats with the antipsychotic haloperidol using a clinically relevant treatment regimen. We then assessed the effects of a 5-HT2 receptor antagonist (ritanserin; 0.01 and 0.1mg/kg) and of a 5-HT2A receptor antagonist (MDL100,907; 0.025-0.1mg/kg) on amphetamine-induced psychomotor activity. Antipsychotic-treated rats showed increased amphetamine-induced locomotion relative to antipsychotic-naïve rats, indicating a dopamine supersensitive state. At the highest dose tested (0.1mg/kg for both antagonists), both ritanserin and MDL100,907 suppressed amphetamine-induced locomotion in antipsychotic-treated rats, while having no effect on this behaviour in control rats. In parallel, antipsychotic treatment decreased 5-HT2A receptor density in the prelimbic cortex and nucleus accumbens core and increased 5-HT2A receptor density in the caudate-putamen. Thus, activation of either 5-HT2 receptors or of 5-HT2A receptors selectively is required for the full expression of antipsychotic-induced dopamine supersensitivity. In addition, antipsychotic-induced dopamine supersensitivity enhances the ability of 5-HT2/5-HT2A receptors to modulate dopamine-dependent behaviours. These effects are potentially linked to changes in 5-HT2A receptor density in the prefrontal cortex and the striatum. These observations raise the possibility that blockade of 5-HT2A receptors might overcome some of the behavioural manifestations of antipsychotic-induced dopamine supersensitivity. PMID:26508706

  18. Quantitative phosphoproteomics unravels biased phosphorylation of serotonin 2A receptor at Ser280 by hallucinogenic versus nonhallucinogenic agonists.

    Science.gov (United States)

    Karaki, Samah; Becamel, Carine; Murat, Samy; Mannoury la Cour, Clotilde; Millan, Mark J; Prézeau, Laurent; Bockaert, Joël; Marin, Philippe; Vandermoere, Franck

    2014-05-01

    The serotonin 5-HT(2A) receptor is a primary target of psychedelic hallucinogens such as lysergic acid diethylamine, mescaline, and psilocybin, which reproduce some of the core symptoms of schizophrenia. An incompletely resolved paradox is that only some 5-HT(2A) receptor agonists exhibit hallucinogenic activity, whereas structurally related agonists with comparable affinity and activity lack such a psychoactive activity. Using a strategy combining stable isotope labeling by amino acids in cell culture with enrichment in phosphorylated peptides by means of hydrophilic interaction liquid chromatography followed by immobilized metal affinity chromatography, we compared the phosphoproteome in HEK-293 cells transiently expressing the 5-HT(2A) receptor and exposed to either vehicle or the synthetic hallucinogen 1-[2,5-dimethoxy-4-iodophenyl]-2-aminopropane (DOI) or the nonhallucinogenic 5-HT(2A) agonist lisuride. Among the 5995 identified phosphorylated peptides, 16 sites were differentially phosphorylated upon exposure of cells to DOI versus lisuride. These include a serine (Ser(280)) located in the third intracellular loop of the 5-HT(2A) receptor, a region important for its desensitization. The specific phosphorylation of Ser(280) by hallucinogens was further validated by quantitative mass spectrometry analysis of immunopurified receptor digests and by Western blotting using a phosphosite specific antibody. The administration of DOI, but not of lisuride, to mice, enhanced the phosphorylation of 5-HT(2A) receptors at Ser(280) in the prefrontal cortex. Moreover, hallucinogens induced a less pronounced desensitization of receptor-operated signaling in HEK-293 cells and neurons than did nonhallucinogenic agonists. The mutation of Ser(280) to aspartic acid (to mimic phosphorylation) reduced receptor desensitization by nonhallucinogenic agonists, whereas its mutation to alanine increased the ability of hallucinogens to desensitize the receptor. This study reveals a biased

  19. Quantitative Phosphoproteomics Unravels Biased Phosphorylation of Serotonin 2A Receptor at Ser280 by Hallucinogenic versus Nonhallucinogenic Agonists*

    Science.gov (United States)

    Karaki, Samah; Becamel, Carine; Murat, Samy; Mannoury la Cour, Clotilde; Millan, Mark J.; Prézeau, Laurent; Bockaert, Joël; Marin, Philippe; Vandermoere, Franck

    2014-01-01

    The serotonin 5-HT2A receptor is a primary target of psychedelic hallucinogens such as lysergic acid diethylamine, mescaline, and psilocybin, which reproduce some of the core symptoms of schizophrenia. An incompletely resolved paradox is that only some 5-HT2A receptor agonists exhibit hallucinogenic activity, whereas structurally related agonists with comparable affinity and activity lack such a psychoactive activity. Using a strategy combining stable isotope labeling by amino acids in cell culture with enrichment in phosphorylated peptides by means of hydrophilic interaction liquid chromatography followed by immobilized metal affinity chromatography, we compared the phosphoproteome in HEK-293 cells transiently expressing the 5-HT2A receptor and exposed to either vehicle or the synthetic hallucinogen 1-[2,5-dimethoxy-4-iodophenyl]-2-aminopropane (DOI) or the nonhallucinogenic 5-HT2A agonist lisuride. Among the 5995 identified phosphorylated peptides, 16 sites were differentially phosphorylated upon exposure of cells to DOI versus lisuride. These include a serine (Ser280) located in the third intracellular loop of the 5-HT2A receptor, a region important for its desensitization. The specific phosphorylation of Ser280 by hallucinogens was further validated by quantitative mass spectrometry analysis of immunopurified receptor digests and by Western blotting using a phosphosite specific antibody. The administration of DOI, but not of lisuride, to mice, enhanced the phosphorylation of 5-HT2A receptors at Ser280 in the prefrontal cortex. Moreover, hallucinogens induced a less pronounced desensitization of receptor-operated signaling in HEK-293 cells and neurons than did nonhallucinogenic agonists. The mutation of Ser280 to aspartic acid (to mimic phosphorylation) reduced receptor desensitization by nonhallucinogenic agonists, whereas its mutation to alanine increased the ability of hallucinogens to desensitize the receptor. This study reveals a biased phosphorylation of

  20. Activation of serotonin 2A receptors underlies the psilocybin-induced effects on α oscillations, N170 visual-evoked potentials, and visual hallucinations.

    Science.gov (United States)

    Kometer, Michael; Schmidt, André; Jäncke, Lutz; Vollenweider, Franz X

    2013-06-19

    Visual illusions and hallucinations are hallmarks of serotonergic hallucinogen-induced altered states of consciousness. Although the serotonergic hallucinogen psilocybin activates multiple serotonin (5-HT) receptors, recent evidence suggests that activation of 5-HT2A receptors may lead to the formation of visual hallucinations by increasing cortical excitability and altering visual-evoked cortical responses. To address this hypothesis, we assessed the effects of psilocybin (215 μg/kg vs placebo) on both α oscillations that regulate cortical excitability and early visual-evoked P1 and N170 potentials in healthy human subjects. To further disentangle the specific contributions of 5-HT2A receptors, subjects were additionally pretreated with the preferential 5-HT2A receptor antagonist ketanserin (50 mg vs placebo). We found that psilocybin strongly decreased prestimulus parieto-occipital α power values, thus precluding a subsequent stimulus-induced α power decrease. Furthermore, psilocybin strongly decreased N170 potentials associated with the appearance of visual perceptual alterations, including visual hallucinations. All of these effects were blocked by pretreatment with the 5-HT2A antagonist ketanserin, indicating that activation of 5-HT2A receptors by psilocybin profoundly modulates the neurophysiological and phenomenological indices of visual processing. Specifically, activation of 5-HT2A receptors may induce a processing mode in which stimulus-driven cortical excitation is overwhelmed by spontaneous neuronal excitation through the modulation of α oscillations. Furthermore, the observed reduction of N170 visual-evoked potentials may be a key mechanism underlying 5-HT2A receptor-mediated visual hallucinations. This change in N170 potentials may be important not only for psilocybin-induced states but also for understanding acute hallucinatory states seen in psychiatric disorders, such as schizophrenia and Parkinson's disease.

  1. Stabilization of Tryptophan Hydroxylase 2 by L-Phenylalanine Induced Dimerization

    DEFF Research Database (Denmark)

    Tidemand, Kasper Damgaard; Christensen, Hans Erik Mølager; Hoeck, Niclas;

    2016-01-01

    Tryptophan hydroxylase 2 (TPH2) catalyses the initial and rate-limiting step in the biosynthesis of serotonin, which is associated with a variety of disorders such as depression, obsessive compulsive disorder, and schizophrenia. Full length TPH2 is poorly characterized due to low purification qua...

  2. Association between Tryptophan Hydroxylase 2 Gene Polymorphism and Completed Suicide

    Science.gov (United States)

    Fudalej, Sylwia; Ilgen, Mark; Fudalej, Marcin; Kostrzewa, Grazyna; Barry, Kristen; Wojnar, Marcin; Krajewski, Pawel; Blow, Frederic; Ploski, Rafal

    2010-01-01

    The association between suicide and a single nucleotide polymorphism (rs1386483) was examined in the recently identified tryptophan hydroxylase 2 (TPH2) gene. Blood samples of 143 suicide victims and 162 age- and sex-matched controls were examined. The frequency of the TT genotype in the TPH2 polymorphism was higher in suicide victims than in…

  3. Synthesis and biological evaluation of a series of benzoxazole/benzothiazole-containing 2,3-dihydrobenzo[b][1,4]dioxine derivatives as potential antidepressants.

    Science.gov (United States)

    Wang, Songlin; Chen, Yin; Zhao, Song; Xu, Xiangqing; Liu, Xin; Liu, Bi-Feng; Zhang, Guisen

    2014-04-01

    A series of benzoxazole/benzothiazole-2,3-dihydrobenzo[b][1,4]dioxine derivatives (5a-5d and 8a-8j) was synthesized. Compounds were evaluated for binding affinities at the 5-HT1A and 5-HT2A receptors. Antidepressant activities of the compounds were screened using the forced swimming test (FST) and the tail suspension test (TST). The results indicated that the compounds exhibited high affinities for the 5-HT1A and 5-HT2A receptors and showed a marked antidepressant-like activity. Compound 8g exhibited high affinities for the 5-HT1A (Ki=17 nM) and 5-HT2A (Ki=0.71 nM) receptors; it also produced a decrease of the immobility time and exhibited potent antidepressant-like effects in the FST and TST in mice.

  4. Brain serotonin signaling does not determine sexual preference in male mice.

    Directory of Open Access Journals (Sweden)

    Mariana Angoa-Pérez

    Full Text Available It was reported recently that male mice lacking brain serotonin (5-HT lose their preference for females (Liu et al., 2011, Nature, 472, 95-100, suggesting a role for 5-HT signaling in sexual preference. Regulation of sex preference by 5-HT lies outside of the well established roles in this behavior established for the vomeronasal organ (VNO and the main olfactory epithelium (MOE. Presently, mice with a null mutation in the gene for tryptophan hydroxylase 2 (TPH2, which are depleted of brain 5-HT, were tested for sexual preference. When presented with inanimate (urine scents from male or estrous female or animate (male or female mouse in estrus sexual stimuli, TPH2-/- males show a clear preference for female over male stimuli. When a TPH2-/- male is offered the simultaneous choice between an estrous female and a male mouse, no sexual preference is expressed. However, when confounding behaviors that are seen among 3 mice in the same cage are controlled, TPH2-/- mice, like their TPH2+/+ counterparts, express a clear preference for female mice. Female TPH2-/- mice are preferred by males over TPH2+/+ females but this does not lead to increased pregnancy success. In fact, if one or both partners in a mating pair are TPH2-/- in genotype, pregnancy success rates are significantly decreased. Finally, expression of the VNO-specific cation channel TRPC2 and of CNGA2 in the MOE of TPH2-/- mice is normal, consistent with behavioral findings that sexual preference of TPH2-/- males for females is intact. In conclusion, 5-HT signaling in brain does not determine sexual preference in male mice. The use of pharmacological agents that are non-selective for the 5-HT neuronal system and that have serious adverse effects may have contributed historically to the stance that 5-HT regulates sexual behavior, including sex partner preference.

  5. Brain serotonin signaling does not determine sexual preference in male mice.

    Science.gov (United States)

    Angoa-Pérez, Mariana; Herrera-Mundo, Nieves; Kane, Michael J; Sykes, Catherine E; Anneken, John H; Francescutti, Dina M; Kuhn, Donald M

    2015-01-01

    It was reported recently that male mice lacking brain serotonin (5-HT) lose their preference for females (Liu et al., 2011, Nature, 472, 95-100), suggesting a role for 5-HT signaling in sexual preference. Regulation of sex preference by 5-HT lies outside of the well established roles in this behavior established for the vomeronasal organ (VNO) and the main olfactory epithelium (MOE). Presently, mice with a null mutation in the gene for tryptophan hydroxylase 2 (TPH2), which are depleted of brain 5-HT, were tested for sexual preference. When presented with inanimate (urine scents from male or estrous female) or animate (male or female mouse in estrus) sexual stimuli, TPH2-/- males show a clear preference for female over male stimuli. When a TPH2-/- male is offered the simultaneous choice between an estrous female and a male mouse, no sexual preference is expressed. However, when confounding behaviors that are seen among 3 mice in the same cage are controlled, TPH2-/- mice, like their TPH2+/+ counterparts, express a clear preference for female mice. Female TPH2-/- mice are preferred by males over TPH2+/+ females but this does not lead to increased pregnancy success. In fact, if one or both partners in a mating pair are TPH2-/- in genotype, pregnancy success rates are significantly decreased. Finally, expression of the VNO-specific cation channel TRPC2 and of CNGA2 in the MOE of TPH2-/- mice is normal, consistent with behavioral findings that sexual preference of TPH2-/- males for females is intact. In conclusion, 5-HT signaling in brain does not determine sexual preference in male mice. The use of pharmacological agents that are non-selective for the 5-HT neuronal system and that have serious adverse effects may have contributed historically to the stance that 5-HT regulates sexual behavior, including sex partner preference. PMID:25706994

  6. Cross-talk between 5-hydroxytryptamine and substance P in the melanogensis and apoptosis of B16F10 melanoma cells.

    Science.gov (United States)

    Zhou, Jia; Geng, Kun-kun; Ping, Feng-feng; Gao, Yue-ying; Liu, Lei; Feng, Bai-nian

    2016-03-15

    Skin pigmentation is a complex process controlled by many different factors. Substance P (SP) regulates many biological functions, including melanogenesis and stress. Our previous study indicated that regulation of SP on melanocyte function was mediated by neurokinin 1 receptor (NK1 receptor). Substantial evidence has accumulated that psychological stress can be associated with skin pigmentation, so that the impact of 5-hydroxytryptamine (5-HT), one of the important factors participating in stress process, on melanogenesis has also been concerned. It has been reported that 5-HT induces melanin synthesis via 5-HT2A receptor. Furthermore, 5-HT2A receptor and NK1 receptor are G-protein coupled receptors (GPCRs) and both expressed on melanocyte, the present study was designed to investigate whether SP has influence on the adjustment function of 5-HT. Our data demonstrated that, SP inhibited 5-HT2A receptor expression to neutralize the pro-melanogenesis effect of 5-HT on B16F10 cells. The up-regulation of NK1 receptor expression was simultaneous with the down-regulation of 5-HT2A receptor treated by SP. This inhibition of 5-HT2A receptor expression by SP could be reversed by NK1 receptor antagonist Spantide I. Our studies indicated that SP could directly induce B16F10 cells apoptosis in vitro. 5-HT and 5-HT2A receptor agonist could mitigate this apoptotic effect of SP. It is the strong evidence of possible cross-talk between GPCRs and giving enlightenments when screening desirable drugs for target receptors. PMID:26872989

  7. Brain serotonin 2A receptor binding: Relations to body mass index, tobacco and alcohol use

    DEFF Research Database (Denmark)

    Erritzoe, D.; Frokjaer, V. G.; Haugbol, S.;

    2009-01-01

    to increased food and alcohol intake, and conversely, stimulation of the serotonergic system induces weight reduction and decreased food/alcohol intake as well as tobacco smoking. To investigate whether body weight, alcohol intake and tobacco smoking were related to the regulation of the cerebral serotonin 2A...... receptor (5-HT(2A)) in humans, we tested in 136 healthy human subjects if body mass index (BMI), degree of alcohol consumption and tobacco smoking was associated to the cerebral in vivo 5-HT(2A) receptor binding as measured with (18)F-altanserin PET. The subjects' BMI's ranged from 18.4 to 42.8 (25...

  8. Regulating prefrontal cortex activation

    DEFF Research Database (Denmark)

    Aznar, Susana; Klein, Anders Bue

    2013-01-01

    pharmacological effect of elevating serotonin levels in anxiety regulation. Recent animal and human functional magnetic resonance studies have pointed to a specific involvement of the 5-hydroxytryptamine (5-HT)2A serotonin receptor in the PFC feedback regulatory projection onto the amygdala. This receptor...... of emotion-based actions, such as addiction and other impulse-related behaviors. In this review, we give an overview of the 5-HT2A receptor distribution (neuronal, intracellular, and anatomical) along with its functional and physiological effect on PFC activation, and how that relates to more recent findings...... of a regulatory effect of the PFC on the emotional control of our actions....

  9. Genetic dysfunction of serotonin 2A receptor hampers response to antidepressant drugs: A translational approach.

    Science.gov (United States)

    Qesseveur, Gaël; Petit, Anne Cécile; Nguyen, Hai Thanh; Dahan, Lionel; Colle, Romain; Rotenberg, Samuel; Seif, Isabelle; Robert, Pauline; David, Denis; Guilloux, Jean-Philippe; Gardier, Alain M; Verstuyft, Céline; Becquemont, Laurent; Corruble, Emmanuelle; Guiard, Bruno P

    2016-06-01

    Pharmacological studies have yielded valuable insights into the role of the serotonin 2A (5-HT2A) receptor in major depressive disorder (MDD) and antidepressant drugs (ADs) response. However, it is still unknown whether genetic variants in the HTR2A gene affect the therapeutic outcome of ADs and the mechanism underlying the regulation of such response remains poorly described. In this context, a translational human-mouse study offers a unique opportunity to address the possibility that variations in the HTR2A gene may represent a relevant marker to predict the efficacy of ADs. In a first part of this study, we investigated in depressed patients the effect of three HTR2A single nucleotide polymorphisms (SNPs), selected for their potential functional consequences on 5-HT2A receptor (rs6313, rs6314 and rs7333412), on response and remission rates after 3 months of antidepressant treatments. We also explored the consequences of the constitutive genetic inactivation of the 5-HT2A receptor (i.e. in 5-HT2A(-/-) mice) on the activity of acute and prolonged administration of SSRIs. Our clinical data indicate that GG patients for the rs7333412 SNP were less prone to respond to ADs than AA/AG patients. In the preclinical study, we demonstrated that the 5-HT2A receptor exerts an inhibitory influence on the neuronal activity of the serotonergic system after acute administration of SSRIs. However, while the chronic administration of the SSRIs escitalopram or fluoxetine elicited a progressive increased in the firing rate of 5-HT neurons in 5-HT2A(+/+) mice, it failed to do so in 5-HT2A(-/-) mutants. These electrophysiological impairments were associated with a decreased ability of the chronic administration of fluoxetine to stimulate hippocampal plasticity and to produce antidepressant-like activities. Genetic loss of the 5-HT2A receptor compromised the activity of chronic treatment with SSRIs, making this receptor a putative marker to predict ADs response. PMID:26764241

  10. Serotonergic stimulation of the rat hypothalamo-pituitary-adrenal axis

    DEFF Research Database (Denmark)

    Mikkelsen, Jens D; Hay-Schmidt, Anders; Kiss, Alexander

    2004-01-01

    Acute stimulation of the hypothalamo-pituitary-adrenal (HPA) axis by selective serotonin reuptake inhibitors (SSRIs) is mediated by several postsynaptic 5-HT receptor subtypes. Activation of 5-HT(1A) and 5-HT(2A) receptors increases plasma corticosterone levels, and it is likely that these receptor...... that the two serotonin receptor subtypes affect the HPA axis via a central target. In conclusion, 5-HT(1A) and 5-HT(2A) receptors regulate corticotrophin-releasing hormone (CRH) neurons via distinct but strongly interacting pathways, probably converging on the same neurons in the hypothalamus....

  11. Serotonergic systems in the balance: CRHR1 and CRHR2 differentially control stress-induced serotonin synthesis.

    Science.gov (United States)

    Donner, Nina C; Siebler, Philip H; Johnson, Danté T; Villarreal, Marcos D; Mani, Sofia; Matti, Allison J; Lowry, Christopher A

    2016-01-01

    Anxiety and affective disorders are often associated with hypercortisolism and dysfunctional serotonergic systems, including increased expression of TPH2, the gene encoding the rate-limiting enzyme of neuronal serotonin synthesis. We previously reported that chronic glucocorticoid exposure is anxiogenic and increases rat Tph2 mRNA expression, but it was still unclear if this also translates to increased TPH2 protein levels and in vivo activity of the enzyme. Here, we found that adult male rats treated with corticosterone (CORT, 100 μg/ml) via the drinking water for 21 days indeed show increased TPH2 protein expression in the dorsal and ventral part of the dorsal raphe nucleus (DRD, DRV) during the light phase, abolishing the enzyme's diurnal rhythm. In a second study, we systemically blocked the conversion of 5-hydroxytryptophan (5-HTP) to serotonin immediately before rats treated with CORT or vehicle were either exposed to 30 min acoustic startle stress or home cage control conditions. This allowed us to measure 5-HTP accumulation as a direct readout of basal versus stress-induced in vivo TPH2 activity. As expected, basal TPH2 activity was elevated in the DRD, DRV and MnR of CORT-treated rats. In response to stress, a multitude of serotonergic systems reacted with increased TPH2 activity, but the stress-, anxiety-, and learned helplessness-related dorsal and caudal DR (DRD/DRC) displayed stress-induced increases in TPH2 activity only after chronic CORT-treatment. To address the mechanisms underlying this region-specific CORT-dependent sensitization, we stereotaxically implanted CORT-treated rats with cannulae targeting the DR, and pharmacologically blocked either corticotropin-releasing hormone receptor type 1 (CRHR1) or type 2 (CRHR2) 10 min prior to acoustic startle stress. CRHR2 blockade prevented stress-induced increases of TPH2 activity within the DRD/DRC, while blockade of CRHR1 potentiated stress-induced TPH2 activity in the entire DR. Stress-induced TPH2

  12. Cloning, expression, purification and characterization of tryptophan hydroxylase variants

    DEFF Research Database (Denmark)

    Boesen, Jane

    such as depression and obsessive-compulsive disorder (OCD). Characterization of TPH and elucidation of the enzymes regulation and catalytic mechanism is therefore vital to our understanding of the serotonin balance. This study concerns variants of both human TPH isoform 1 (hTPH1) and human TPH isoform 2 (h PH2...... the variant. The GST-rhTPH1 variant could be purified using affinity chromatography followed by gel filtration with high purity and a yield of 40 mg/l culture. The purified GST-rhTPH1 exists as a dimer in solution due to dimerization of GST. The GST could be cleaved successfully from the fusion protein using...

  13. Enhanced transcription of contractile 5-hydroxytryptamine 2A receptors via extracellular signal-regulated kinase 1/2 after organ culture of rat mesenteric artery

    DEFF Research Database (Denmark)

    Cao, Yong-Xiao; He, Lang-Chong; Xu, Cang-Bao;

    2005-01-01

    5-Hydroxytryptamine (5-HT) has been found to elicit enhanced contractile effects in some vascular disorders. The present study was designed to examine if vascular 5-HT2A receptors are up-regulated during organ culture and if the extracellular signal-regulated protein kinase 1/2 (ERK1/2) pathways ...

  14. Robust upregulation of serotonin 2A receptors after chronic spinal transection of rats: An immunohistochemical study

    DEFF Research Database (Denmark)

    Kong, Xiang-Yu; Wienecke, Jacob; Hultborn, Hans;

    2010-01-01

    of the sacrocaudal spinal cord. The results show that in the spinalized rats the immunoreactivity of 5-HT2A receptors below the lesion is dramatically increased in the motoneuron soma and its proximal dendritic territory, most likely also in their distal dendritic territory, to a level 3-5-fold higher than...

  15. Novelty-induced activity-regulated cytoskeletal-associated protein (Arc) expression in frontal cortex requires serotonin 2A receptor activation

    DEFF Research Database (Denmark)

    Santini, Martin; Klein, A B; El-Sayed, M;

    2011-01-01

    Many psychiatric disorders are characterized by cognitive and emotional alterations that are related to abnormal function of the frontal cortex (FC). FC is involved in working memory and decision making and is activated following exposure to a novel environment. The serotonin 2A receptor (5-HT(2A...

  16. The Reduction of Baseline Serotonin 2A Receptors in Mild Cognitive Impairment is Stable at Two-year Follow-up

    DEFF Research Database (Denmark)

    Marner, Lisbeth; Knudsen, Gitte M; Madsen, Karine;

    2011-01-01

    We previously demonstrated a 20-30% reduction in cortical 5-HT2A receptor binding in patients with mild cognitive impairment (MCI) as compared to healthy subjects. Here we present a two-year follow-up of 14 patients and 12 healthy age-matched subjects. Baseline and follow-up partial volume...

  17. Receptor interaction profiles of novel psychoactive tryptamines compared with classic hallucinogens.

    Science.gov (United States)

    Rickli, Anna; Moning, Olivier D; Hoener, Marius C; Liechti, Matthias E

    2016-08-01

    The present study investigated interactions between the novel psychoactive tryptamines DiPT, 4-OH-DiPT, 4-OH-MET, 5-MeO-AMT, and 5-MeO-MiPT at monoamine receptors and transporters compared with the classic hallucinogens lysergic acid diethylamide (LSD), psilocin, N,N-dimethyltryptamine (DMT), and mescaline. We investigated binding affinities at human monoamine receptors and determined functional serotonin (5-hydroxytryptamine [5-HT]) 5-HT2A and 5-HT2B receptor activation. Binding at and the inhibition of human monoamine uptake transporters and transporter-mediated monoamine release were also determined. All of the novel tryptamines interacted with 5-HT2A receptors and were partial or full 5-HT2A agonists. Binding affinity to the 5-HT2A receptor was lower for all of the tryptamines, including psilocin and DMT, compared with LSD and correlated with the reported psychoactive doses in humans. Several tryptamines, including psilocin, DMT, DiPT, 4-OH-DiPT, and 4-OH-MET, interacted with the serotonin transporter and partially the norepinephrine transporter, similar to 3,4-methylenedioxymethamphetamine but in contrast to LSD and mescaline. LSD but not the tryptamines interacted with adrenergic and dopaminergic receptors. In conclusion, the receptor interaction profiles of the tryptamines predict hallucinogenic effects that are similar to classic serotonergic hallucinogens but also MDMA-like psychoactive properties. PMID:27216487

  18. Receptor interaction profiles of novel psychoactive tryptamines compared with classic hallucinogens.

    Science.gov (United States)

    Rickli, Anna; Moning, Olivier D; Hoener, Marius C; Liechti, Matthias E

    2016-08-01

    The present study investigated interactions between the novel psychoactive tryptamines DiPT, 4-OH-DiPT, 4-OH-MET, 5-MeO-AMT, and 5-MeO-MiPT at monoamine receptors and transporters compared with the classic hallucinogens lysergic acid diethylamide (LSD), psilocin, N,N-dimethyltryptamine (DMT), and mescaline. We investigated binding affinities at human monoamine receptors and determined functional serotonin (5-hydroxytryptamine [5-HT]) 5-HT2A and 5-HT2B receptor activation. Binding at and the inhibition of human monoamine uptake transporters and transporter-mediated monoamine release were also determined. All of the novel tryptamines interacted with 5-HT2A receptors and were partial or full 5-HT2A agonists. Binding affinity to the 5-HT2A receptor was lower for all of the tryptamines, including psilocin and DMT, compared with LSD and correlated with the reported psychoactive doses in humans. Several tryptamines, including psilocin, DMT, DiPT, 4-OH-DiPT, and 4-OH-MET, interacted with the serotonin transporter and partially the norepinephrine transporter, similar to 3,4-methylenedioxymethamphetamine but in contrast to LSD and mescaline. LSD but not the tryptamines interacted with adrenergic and dopaminergic receptors. In conclusion, the receptor interaction profiles of the tryptamines predict hallucinogenic effects that are similar to classic serotonergic hallucinogens but also MDMA-like psychoactive properties.

  19. Serotonergic projections from the raphe nuclei to the subthalamic nucleus; a retrograde- and anterograde neuronal tracing study

    DEFF Research Database (Denmark)

    Reznitsky, Martin; Plenge, Per; Hay-Schmidt, Anders

    2016-01-01

    the 5-HT1A and 5-HT2A not were present. Retrograde tracer FluoroGold or Choleratoxin subunit B were iontophoretically delivered in the STN and combined with immunohistochemistry for 5-HT in order to map the topographic organization in the dorsal raphe system. The study showed that approximately 320...

  20. Drug: D08397 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available 61 429.5292 D08397.gif Antimigraine; Serotonin antagonist ATC code: N02CX01 5-HT2A-receptor antagonist [HSA:...ERVOUS SYSTEM N02 ANALGESICS N02C ANTIMIGRAINE PREPARATIONS N02CX Other antimigraine

  1. Ritanserin as add-on medication to neuroleptic therapy for patients with chronic or subchronic schizophrenia

    NARCIS (Netherlands)

    Den Boer, JA; Vahlne, JO; Post, P; Heck, AH; Daubenton, F; Olbrich, R

    2000-01-01

    The effect of ritanserin, a potent 5HT(2A/2C) receptor antagonist, used as an add-on medication to neuroleptic treatmentin patients with schizophrenia, was compared with that of placebo, in an international, double-blind, parallel-group study. Previously established neuroleptic therapy was maintaine

  2. Similar serotonin-2A receptor binding in rats with different coping styles or levels of aggression

    DEFF Research Database (Denmark)

    Visser, Anniek Kd; Ettrup, Anders; Klein, Anders Bue;

    2015-01-01

    Individual differences in coping style emerge as a function of underlying variability in the activation of a mesocorticolimbic brain circuitry. Particularly serotonin seems to play an important role. For this reason, we assessed serotonin-2A receptor (5-HT2A R) binding in the brain of rats with d...

  3. Polymorphisms of serotonin receptor 2A and 2C genes and COMT in relation to obesity and type 2 diabetes

    DEFF Research Database (Denmark)

    Kring, Sofia I I; Werge, Thomas; Holst, Claus;

    2009-01-01

    BACKGROUND: Candidate genes of psychological importance include 5HT2A, 5HT2C, and COMT, implicated in the serotonin, noradrenaline and dopamine pathways, which also may be involved in regulation of energy balance. We investigated the associations of single nucleotide polymorphisms (SNPs) of these...

  4. Drug: D06633 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available 33.gif Insomnia, major depression, and schizophrenia 5-HT2A-receptor antagonist [HSA:3356] [KO:K04157] hsa04...D06633 Drug Pruvanserin hydrochloride (USAN) C22H21FN4O. HCl 412.1466 412.8877 D066

  5. Cerebral markers of the serotonergic system in rat models of obesity and after Roux-en-Y gastric bypass

    DEFF Research Database (Denmark)

    Ratner, Cecilia; Ettrup, Anders; Bueter, Marco;

    2012-01-01

    markers. Using receptor autoradiography, brain regional-densities of the serotonin transporter (SERT) and the 5-HT(2A) and 5-HT(4) receptors were measured in (i) selectively bred polygenic diet-induced obese (pgDIO) rats, (ii) outbred DIO rats, and (iii) Roux-en-Y gastric bypass (RYGB)-operated rats. pg...

  6. Drug: D06632 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available , major depression, and schizophrenia 5-HT2A-receptor antagonist [HSA:3356] [KO:K04157] hsa04020(3356) Calci...D06632 Drug Pruvanserin (USAN/INN) C22H21FN4O 376.1699 376.4267 D06632.gif Insomnia

  7. Dihydrobenzofuran analogues of hallucinogens. 4. Mescaline derivatives.

    Science.gov (United States)

    Monte, A P; Waldman, S R; Marona-Lewicka, D; Wainscott, D B; Nelson, D L; Sanders-Bush, E; Nichols, D E

    1997-09-12

    Dihydrobenzofuran and tetrahydrobenzodifuran functionalities were employed as conformationally restricted bioisosteres of the aromatic methoxy groups in the prototypical hallucinogen, mescaline (1). Thus, 4-(2-aminoethyl)-6,7-dimethoxy-2,3-dihydrobenzofuran hydrochloride (8) and 1-(8-methoxy-2,3,5,6-tetrahydrobenzo[1,2-b:5,4-b']difuran-4-yl)-2- aminoethane hydrochloride (9) were prepared and evaluated along with 1 for activity in the two-lever drug discrimination (DD) paradigm in rats trained to discriminate saline from LSD tartrate (0.08 mg/kg). Also, 1, 8, and 9 were assayed for their ability to displace [3H]ketanserin from rat cortical homogenate 5-HT2A receptors and [3H]8-OH-DPAT from rat hippocampal homogenate 5-HT1A receptors. In addition, these compounds were evaluated for their ability to compete for agonist and antagonist binding to cells expressing cloned human 5-HT2A, 5-HT2B, and 5-HT2C receptors. Finally, agonist efficacy was assessed by measurement of phosphoinositide hydrolysis in NIH 3T3 cells expressing the rat 5-HT2A or 5-HT2C receptors. Although 1 fully substituted for LSD in the DD assays (ED50 = 33.5 mumol/kg), neither 8 nor 9 substituted for LSD, with just 50% of the rats administered 8 selecting the drug lever, and only 29% of the rats administered 9 selecting the drug lever. All of the test compounds had micromolar affinity for the 5-HT1A and 5-HT2A receptors in rat brain homogenate. Curiously, the rank order of affinities of the compounds at 5-HT2A sites was opposite their order of potency in the behavioral assay. An evaluation for ability to stimulate phosphoinositide turnover as a measure of functional efficacy revealed that all the compounds were of approximately equal efficacy to serotonin in 5-HT2C receptors. At 5-HT2A receptors, however, 8 and 9 were significantly less efficacious, eliciting only 61 and 45%, respectively, of the maximal response. These results are consistent with the proposed mechanism of action for phenethylamine

  8. The HIV antiretroviral drug efavirenz has LSD-like properties.

    Science.gov (United States)

    Gatch, Michael B; Kozlenkov, Alexey; Huang, Ren-Qi; Yang, Wenjuan; Nguyen, Jacques D; González-Maeso, Javier; Rice, Kenner C; France, Charles P; Dillon, Glenn H; Forster, Michael J; Schetz, John A

    2013-11-01

    Anecdotal reports have surfaced concerning misuse of the HIV antiretroviral medication efavirenz ((4S)-6-chloro-4-(2-cyclopropylethynyl)-4-(trifluoromethyl)-2,4-dihydro-1H-3,1-benzoxazin-2-one) by HIV patients and non-infected teens who crush the pills and smoke the powder for its psychoactive effects. Molecular profiling of the receptor pharmacology of efavirenz pinpointed interactions with multiple established sites of action for other known drugs of abuse including catecholamine and indolamine transporters, and GABAA and 5-HT(2A) receptors. In rodents, interaction with the 5-HT(2A) receptor, a primary site of action of lysergic acid diethylamine (LSD), appears to dominate efavirenz's behavioral profile. Both LSD and efavirenz reduce ambulation in a novel open-field environment. Efavirenz occasions drug-lever responding in rats discriminating LSD from saline, and this effect is abolished by selective blockade of the 5-HT(2A) receptor. Similar to LSD, efavirenz induces head-twitch responses in wild-type, but not in 5-HT(2A)-knockout, mice. Despite having GABAA-potentiating effects (like benzodiazepines and barbiturates), and interactions with dopamine transporter, serotonin transporter, and vesicular monoamine transporter 2 (like cocaine and methamphetamine), efavirenz fails to maintain responding in rats that self-administer cocaine, and it fails to produce a conditioned place preference. Although its molecular pharmacology is multifarious, efavirenz's prevailing behavioral effect in rodents is consistent with LSD-like activity mediated via the 5-HT(2A) receptor. This finding correlates, in part, with the subjective experiences in humans who abuse efavirenz and with specific dose-dependent adverse neuropsychiatric events, such as hallucinations and night terrors, reported by HIV patients taking it as a medication.

  9. Inhibition of alpha oscillations through serotonin-2A receptor activation underlies the visual effects of ayahuasca in humans.

    Science.gov (United States)

    Valle, Marta; Maqueda, Ana Elda; Rabella, Mireia; Rodríguez-Pujadas, Aina; Antonijoan, Rosa Maria; Romero, Sergio; Alonso, Joan Francesc; Mañanas, Miquel Àngel; Barker, Steven; Friedlander, Pablo; Feilding, Amanda; Riba, Jordi

    2016-07-01

    Ayahuasca is an Amazonian psychotropic plant tea typically obtained from two plants, Banisteriopsis caapi and Psychotria viridis. It contains the psychedelic 5-HT2A and sigma-1 agonist N,N-dimethyltryptamine (DMT) plus β-carboline alkaloids with monoamine-oxidase (MAO)-inhibiting properties. Although the psychoactive effects of ayahuasca have commonly been attributed solely to agonism at the 5-HT2A receptor, the molecular target of classical psychedelics, this has not been tested experimentally. Here we wished to study the contribution of the 5-HT2A receptor to the neurophysiological and psychological effects of ayahuasca in humans. We measured drug-induced changes in spontaneous brain oscillations and subjective effects in a double-blind randomized placebo-controlled study involving the oral administration of ayahuasca (0.75mg DMT/kg body weight) and the 5-HT2A antagonist ketanserin (40mg). Twelve healthy, experienced psychedelic users (5 females) participated in four experimental sessions in which they received the following drug combinations: placebo+placebo, placebo+ayahuasca, ketanserin+placebo and ketanserin+ayahuasca. Ayahuasca induced EEG power decreases in the delta, theta and alpha frequency bands. Current density in alpha-band oscillations in parietal and occipital cortex was inversely correlated with the intensity of visual imagery induced by ayahuasca. Pretreatment with ketanserin inhibited neurophysiological modifications, reduced the correlation between alpha and visual effects, and attenuated the intensity of the subjective experience. These findings suggest that despite the chemical complexity of ayahuasca, 5-HT2A activation plays a key role in the neurophysiological and visual effects of ayahuasca in humans. PMID:27039035

  10. Effects of the hallucinogen 2,5-dimethoxy-4-iodophenethylamine (2C-I) and superpotent N-benzyl derivatives on the head twitch response.

    Science.gov (United States)

    Halberstadt, Adam L; Geyer, Mark A

    2014-02-01

    N-benzyl substitution markedly enhances the affinity of phenethylamine hallucinogens at the 5-HT(2A) receptor. N-benzyl substituted derivatives of 2,5-dimethoxy-4-iodophenethylamine (2C-I), such as N-(2-methoxybenzyl)-2,5-dimethoxy-4-iodophenethylamine (25I-NBOMe) and N-(2,3-methylenedioxybenzyl)-2,5-dimethoxy-4-iodophenethylamine (25I-NBMD), have appeared recently as designer drugs, but have not been characterized behaviorally. The head twitch response (HTR) is induced by 5-HT(2A) receptor activation in rats and mice, and is widely used as a behavioral proxy for hallucinogen effects in humans. Nevertheless, it is not clear whether phenethylamine hallucinogens reliably provoke this behavior. Hence, we investigated whether 2C-I, 25I-NBOMe and 25I-NBMD induce head twitches in C57BL/6J mice. The HTR was assessed using a head-mounted magnet and a magnetometer coil. 2C-I (1-10 mg/kg SC), 25I-NBOMe (0.1-1 mg/kg SC), and 25I-NBMD (1-10 mg/kg SC) induced the HTR. 25I-NBOMe displayed 14-fold higher potency than 2C-I, and the selective 5-HT(2A) antagonist M100,907 completely blocked the HTR induced by all three compounds. These findings show that phenethylamine hallucinogens induce the HTR by activating 5-HT(2A) receptors. Our results demonstrate that 25I-NBOMe is a highly potent derivative of 2C-I, confirming previous in vitro findings that N-benzyl substitution increases 5-HT(2A) affinity. Given the high potency and ease of synthesis of N-benzylphenethylamines, it is likely that the recreational use of these hallucinogens will become more widespread in the future.

  11. Psilocybin-induced deficits in automatic and controlled inhibition are attenuated by ketanserin in healthy human volunteers.

    Science.gov (United States)

    Quednow, Boris B; Kometer, Michael; Geyer, Mark A; Vollenweider, Franz X

    2012-02-01

    The serotonin-2A receptor (5-HT(2A)R) has been implicated in the pathogenesis of schizophrenia and related inhibitory gating and behavioral inhibition deficits of schizophrenia patients. The hallucinogen psilocybin disrupts automatic forms of sensorimotor gating and response inhibition in humans, but it is unclear so far whether the 5-HT(2A)R or 5-HT(1A)R agonist properties of its bioactive metabolite psilocin account for these effects. Thus, we investigated whether psilocybin-induced deficits in automatic and controlled inhibition in healthy humans could be attenuated by the 5-HT(2A/2C)R antagonist ketanserin. A total of 16 healthy participants received placebo, ketanserin (40 mg p.o.), psilocybin (260 μg/kg p.o.), or psilocybin plus ketanserin in a double-blind, randomized, and counterbalanced order. Sensorimotor gating was measured by prepulse inhibition (PPI) of the acoustic startle response. The effects on psychopathological core dimensions and behavioral inhibition were assessed by the altered states of consciousness questionnaire (5D-ASC), and the Color-Word Stroop Test. Psilocybin decreased PPI at short lead intervals (30 ms), increased all 5D-ASC scores, and selectively increased errors in the interference condition of the Stroop Test. Stroop interference and Stroop effect of the response latencies were increased under psilocybin as well. Psilocybin-induced alterations were attenuated by ketanserin pretreatment, whereas ketanserin alone had no significant effects. These findings suggest that the disrupting effects of psilocybin on automatic and controlled inhibition processes are attributable to 5-HT(2A)R stimulation. Sensorimotor gating and attentional control deficits of schizophrenia patients might be due to changes within the 5-HT(2A)R system. PMID:21956447

  12. Psilocybin-induced deficits in automatic and controlled inhibition are attenuated by ketanserin in healthy human volunteers.

    Science.gov (United States)

    Quednow, Boris B; Kometer, Michael; Geyer, Mark A; Vollenweider, Franz X

    2012-02-01

    The serotonin-2A receptor (5-HT(2A)R) has been implicated in the pathogenesis of schizophrenia and related inhibitory gating and behavioral inhibition deficits of schizophrenia patients. The hallucinogen psilocybin disrupts automatic forms of sensorimotor gating and response inhibition in humans, but it is unclear so far whether the 5-HT(2A)R or 5-HT(1A)R agonist properties of its bioactive metabolite psilocin account for these effects. Thus, we investigated whether psilocybin-induced deficits in automatic and controlled inhibition in healthy humans could be attenuated by the 5-HT(2A/2C)R antagonist ketanserin. A total of 16 healthy participants received placebo, ketanserin (40 mg p.o.), psilocybin (260 μg/kg p.o.), or psilocybin plus ketanserin in a double-blind, randomized, and counterbalanced order. Sensorimotor gating was measured by prepulse inhibition (PPI) of the acoustic startle response. The effects on psychopathological core dimensions and behavioral inhibition were assessed by the altered states of consciousness questionnaire (5D-ASC), and the Color-Word Stroop Test. Psilocybin decreased PPI at short lead intervals (30 ms), increased all 5D-ASC scores, and selectively increased errors in the interference condition of the Stroop Test. Stroop interference and Stroop effect of the response latencies were increased under psilocybin as well. Psilocybin-induced alterations were attenuated by ketanserin pretreatment, whereas ketanserin alone had no significant effects. These findings suggest that the disrupting effects of psilocybin on automatic and controlled inhibition processes are attributable to 5-HT(2A)R stimulation. Sensorimotor gating and attentional control deficits of schizophrenia patients might be due to changes within the 5-HT(2A)R system.

  13. Role of 5-hydroxytryptamine in platelet thrombus formation and mechanisms of inhibition of thrombus formation by 5-hydroxytryptamine2A antagonists in rabbits.

    Science.gov (United States)

    Takano, S

    1995-01-01

    The role of 5-hydroxytryptamine (5-HT) in platelet thrombus formation and in the mechanisms of inhibition of thrombus formation by 5-HT2A antagonists was investigated using a turbidimetric method. Collagen-induced platelet aggregation occurred simultaneously with a release of 5-HT from the platelets. The supernatant of collagen-aggregated platelets induced a further aggregation volume-dependently. This supernatant-induced aggregation was inhibited by either 5-HT2A antagonists or adenosine-diphosphate (ADP) scavenging. 5-Hydroxytryptamine and a small amount of the supernatant shifted the dose-response curves of collagen to the left. The aggregation velocity and the onset of aggregation by collagen were significantly increased by the supernatant, but not by 5-HT. The 5-HT2A antagonists, ketanserin and MCI-9042, returned the dose-response curves of the maximum aggregation and of the aggregation velocity of collagen, which were already amplified by the supernatant, to the original values. The onset of aggregation was delayed by the antagonists, but was not completely returned to the original points. There were distinct differences between the effects of endogenous 5-HT, derived from platelets which were stimulated by collagen, and those of exogenous 5-HT on both extensive platelet activation and amplification of the collagen-induced aggregation. These findings suggest that endogenous 5-HT activates platelets in synergism with ADP. The 5-HT2A antagonists used, block the synergism via 5-HT2A receptors and lead to inhibition of a positive feedback loop of thrombus formation. PMID:8836449

  14. Activation of serotonin2A receptors in the medial septum-diagonal band of Broca complex enhanced working memory in the hemiparkinsonian rats.

    Science.gov (United States)

    Li, Li-Bo; Zhang, Li; Sun, Yi-Na; Han, Ling-Na; Wu, Zhong-Heng; Zhang, Qiao-Jun; Liu, Jian

    2015-04-01

    Serotonin2A (5-HT2A) receptors are highly expressed in the medial septum-diagonal band of Broca complex (MS-DB), especially in parvalbumin (PV)-positive neurons linked to hippocampal theta rhythm, which is involved in cognition. Cognitive impairments commonly occur in Parkinson's disease. Here we performed behavioral, electrophysiological, neurochemical and immunohistochemical studies in rats with complete unilateral 6-hydroxydopamine lesions of the medial forebrain bundle (MFB) to assess the importance of dopamine (DA) depletion and MS-DB 5-HT2A receptors for working memory. The MFB lesions resulted in working memory impairment and decreases in firing rate and density of MS-DB PV-positive neurons, peak frequency of hippocampal theta rhythm, and DA levels in septohippocampal system and medial prefrontal cortex (mPFC) compared to control rats. Intra-MS-DB injection of high affinity 5-HT2A receptor agonist TCB-2 enhanced working memory, increased firing rate of PV-positive neurons and peak frequency of hippocampal theta rhythm, elevated DA levels in the hippocampus and mPFC, and decreased 5-HT level in the hippocampus in control and lesioned rats. Compared to control rats, the duration of the excitatory effect produced by TCB-2 on the firing rate of PV-positive neurons was markedly shortened in lesioned rats, indicating dysfunction of 5-HT2A receptors. These findings suggest that unilateral lesions of the MFB in rats induced working memory deficit, and activation of MS-DB 5-HT2A receptors enhanced working memory, which may be due to changes in the activity of septohippocampal network and monoamine levels in the hippocampus and mPFC.

  15. Attention-deficit hyperactivity disorder in adults: A systematic review and meta-analysis of genetic, pharmacogenetic and biochemical studies.

    Science.gov (United States)

    Bonvicini, C; Faraone, S V; Scassellati, C

    2016-07-01

    found for salivary cortisol, whereas lower serum docosahexaenoic acid (DHA) levels were found in ADHD adults. This last association was significant even after Bonferroni correction and in absence of heterogeneity. Other polyunsaturated fatty acids (PUFAs) such as AA (arachidonic acid), EPA (eicosapentaenoic acid) and DyLA (dihomogammalinolenic acid) levels were not different between patients and controls. No publication biases were observed for these markers. Genes linked to dopaminergic, serotoninergic and noradrenergic signaling, metabolism (DBH, TPH1, TPH2, DDC, MAOA, MAOB, BCHE and TH), neurodevelopment (BDNF and others), the SNARE system and other forty genes/proteins related to different pathways were not meta-analyzed due to insufficient data. In conclusion, we found that there were not enough genetic, pharmacogenetic and biochemical studies of ADHD in adults and that more investigations are needed. Moreover we confirmed a significant role of BAIAP2 and DHA in the etiology of ADHD exclusively in adults. Future research should be focused on the replication of these findings and to assess their specificity for ADHD. PMID:27217152

  16. Physical weight loading induces expression of tryptophan hydroxylase 2 in the brain stem.

    Directory of Open Access Journals (Sweden)

    Joon W Shim

    Full Text Available Sustaining brain serotonin is essential in mental health. Physical activities can attenuate mental problems by enhancing serotonin signaling. However, such activity is not always possible in disabled individuals or patients with dementia. Knee loading, a form of physical activity, has been found to mimic effects of voluntary exercise. Focusing on serotonergic signaling, we addressed a question: Does local mechanical loading to the skeleton elevate expression of tryptophan hydroxylase 2 (tph2 that is a rate-limiting enzyme for brain serotonin? A 5 min knee loading was applied to mice using 1 N force at 5 Hz for 1,500 cycles. A 5-min treadmill running was used as an exercise (positive control, and a 90-min tail suspension was used as a stress (negative control. Expression of tph2 was determined 30 min - 2 h in three brain regions --frontal cortex (FC, ventromedial hypothalamus (VMH, and brain stem (BS. We demonstrated for the first time that knee loading and treadmill exercise upregulated the mRNA level of tph2 in the BS, while tail suspension downregulated it. The protein level of tph2 in the BS was also upregulated by knee loading and downregulated by tail suspension. Furthermore, the downregulation of tph2 mRNA by tail suspension can be partially suppressed by pre-application of knee loading. The expression of tph2 in the FC and VMH was not significantly altered with knee loading. In this study we provided evidence that peripheral mechanical loading can activate central tph2 expression, suggesting that physical cues may mediate tph2-cathalyzed serotonergic signaling in the brain.

  17. 5-HT2 Receptor Regulation of Mitochondrial Genes: Unexpected Pharmacological Effects of Agonists and Antagonists.

    Science.gov (United States)

    Harmon, Jennifer L; Wills, Lauren P; McOmish, Caitlin E; Demireva, Elena Y; Gingrich, Jay A; Beeson, Craig C; Schnellmann, Rick G

    2016-04-01

    In acute organ injuries, mitochondria are often dysfunctional, and recent research has revealed that recovery of mitochondrial and renal functions is accelerated by induction of mitochondrial biogenesis (MB). We previously reported that the nonselective 5-HT2 receptor agonist DOI [1-(4-iodo-2,5-dimethoxyphenyl)propan-2-amine] induced MB in renal proximal tubular cells (RPTCs). The goal of this study was to determine the role of 5-HT2 receptors in the regulation of mitochondrial genes and oxidative metabolism in the kidney. The 5-HT2C receptor agonist CP-809,101 [2-[(3-chlorophenyl)methoxy]-6-(1-piperazinyl)pyrazine] and antagonist SB-242,084 [6-chloro-2,3-dihydro-5-methyl-N-[6-[(2-methyl-3-pyridinyl)oxy]-3-pyridinyl]-1H-indole-1-carboxyamide dihydrochloride] were used to examine the induction of renal mitochondrial genes and oxidative metabolism in RPTCs and in mouse kidneys in the presence and absence of the 5-HT2C receptor. Unexpectedly, both CP-809,101 and SB-242,084 increased RPTC respiration and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) mRNA expression in RPTCs at 1-10 nM. In addition, CP-809,101 and SB-242,084 increased mRNA expression of PGC-1α and the mitochondrial proteins NADH dehydrogenase subunit 1 and NADH dehydrogenase (ubiquinone) β subcomplex 8 in mice. These compounds increased mitochondrial genes in RPTCs in which the 5-HT2C receptor was downregulated with small interfering RNA and in the renal cortex of mice lacking the 5-HT2C receptor. By contrast, the ability of these compounds to increase PGC-1α mRNA and respiration was blocked in RPTCs treated with 5-HT2A receptor small interfering RNA or the 5-HT2A receptor antagonist eplivanserin. In addition, the 5-HT2A receptor agonist NBOH-2C-CN [4-[2-[[(2-hydroxyphenyl)methyl]amino]ethyl]-2,5-dimethoxybenzonitrile] increased RPTC respiration at 1-100 nM. These results suggest that agonism of the 5-HT2A receptor induces MB and that the classic 5-HT2C receptor agonist CP

  18. Deletion of CB2 cannabinoid receptor induces schizophrenia-related behaviors in mice.

    Science.gov (United States)

    Ortega-Alvaro, Antonio; Aracil-Fernández, Auxiliadora; García-Gutiérrez, María S; Navarrete, Francisco; Manzanares, Jorge

    2011-06-01

    The possible role of the CB(2) receptor (CB(2)r) in psychiatric disorders has been considered. Several animal models use knockout (KO) mice that display schizophrenia-like behaviors and this study evaluated the role of CB(2)r in the regulation of such behaviors. Mice lacking the CB(2)r (CB(2)KO) were challenged in open field, light-dark box, elevated plus-maze, tail suspension, step down inhibitory avoidance, and pre-pulse inhibition tests (PPI). Furthermore, the effects of treatment with cocaine and risperidone were evaluated using the OF and the PPI test. Gene expression of dopamine D(2) (D(2)r), adrenergic-α(2C) (α(2C)r), serotonergic 5-HT(2A) and 5-HT(2C) receptors (5-HT(2A)r and 5-HT(2C)r) were studied by RT-PCR in brain regions related to schizophrenia. Deletion of CB(2)r decreased motor activity in the OF test, but enhanced response to acute cocaine and produced mood-related alterations, PPI deficit, and cognitive impairment. Chronic treatment with risperidone tended to impair PPI in WT mice, whereas it 'normalized' the PPI deficit in CB(2)KO mice. CB(2)KO mice presented increased D(2)r and α(2C)r gene expressions in the prefrontal cortex (PFC) and locus coeruleus (LC), decreased 5-HT(2C)r gene expression in the dorsal raphe (DR), and 5-HT(2A)r gene expression in the PFC. Chronic risperidone treatment in WT mice left α(2C)r gene expression unchanged, decreased D(2)r gene expression (15 μg/kg), and decreased 5-HT(2C)r and 5-HT(2A)r in PFC and DR. In CB(2)KO, the gene expression of D(2)r in the PFC, of α(2C)r in the LC, and of 5-HT(2C)r and 5-HT(2A)r in PFC was reduced; 5-HT(2C)r and 5-HT(2A)r gene expressions in DR were increased after treatment with risperidone. These results suggest that deletion of CB(2)r has a relation with schizophrenia-like behaviors. Pharmacological manipulation of CB(2)r may merit further study as a potential therapeutic target for the treatment of schizophrenia-related disorders. PMID:21430651

  19. Synthesis and pharmacological evaluation of piperidine (piperazine)-substituted benzoxazole derivatives as multi-target antipsychotics.

    Science.gov (United States)

    Huang, Ling; Zhang, Wenjun; Zhang, Xiaohua; Yin, Lei; Chen, Bangyin; Song, Jinchun

    2015-11-15

    The present study describes the optimization of a series of novel benzoxazole-piperidine (piperazine) derivatives combining high dopamine D2 and serotonin 5-HT1A, 5-HT2A receptor affinities. Of these derivatives, the pharmacological features of compound 29 exhibited high affinities for the DA D2, 5-HT1A and 5-HT2A receptors, but low affinities for the 5-HT2C and histamine H1 receptors and human ether-a-go-go-related gene (hERG) channels. Furthermore, compound 29 reduced apomorphine-induced climbing and 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI)-induced head twitching without observable catalepsy, even at the highest dose tested. Thus, compound 29 is a promising candidate as a multi-target antipsychotic treatment. PMID:26483200

  20. Recent Advances in the Neuropsychopharmacology of Serotonergic Hallucinogens

    Science.gov (United States)

    Halberstadt, Adam L.

    2014-01-01

    Serotonergic hallucinogens, such as (+)-lysergic acid diethylamide, psilocybin, and mescaline, are somewhat enigmatic substances. Although these drugs are derived from multiple chemical families, they all produce remarkably similar effects in animals and humans, and they show cross-tolerance. This article reviews the evidence demonstrating the serotonin 5-HT2A receptor is the primary site of hallucinogen action. The 5-HT2A receptor is responsible for mediating the effects of hallucinogens in human subjects, as well as in animal behavioral paradigms such as drug discrimination, head twitch response, prepulse inhibition of startle, exploratory behavior, and interval timing. Many recent clinical trials have yielded important new findings regarding the psychopharmacology of these substances. Furthermore, the use of modern imaging and electrophysiological techniques is beginning to help unravel how hallucinogens work in the brain. Evidence is also emerging that hallucinogens may possess therapeutic efficacy. PMID:25036425

  1. Synthesis and pharmacological evaluation of piperidine (piperazine)-substituted benzoxazole derivatives as multi-target antipsychotics.

    Science.gov (United States)

    Huang, Ling; Zhang, Wenjun; Zhang, Xiaohua; Yin, Lei; Chen, Bangyin; Song, Jinchun

    2015-11-15

    The present study describes the optimization of a series of novel benzoxazole-piperidine (piperazine) derivatives combining high dopamine D2 and serotonin 5-HT1A, 5-HT2A receptor affinities. Of these derivatives, the pharmacological features of compound 29 exhibited high affinities for the DA D2, 5-HT1A and 5-HT2A receptors, but low affinities for the 5-HT2C and histamine H1 receptors and human ether-a-go-go-related gene (hERG) channels. Furthermore, compound 29 reduced apomorphine-induced climbing and 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI)-induced head twitching without observable catalepsy, even at the highest dose tested. Thus, compound 29 is a promising candidate as a multi-target antipsychotic treatment.

  2. Drug: D05738 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D05738 Drug Ritanserin (USAN/INN); Tiserton (TN) C27H25F2N3OS 477.1686 477.5687 D05...ication of drugs [BR:br08310] G Protein-coupled receptors Rhodopsin family Serotonin 5-HT2A-receptor [HSA:3356] [KO:K04157] Rita...nserin D05738 Ritanserin (USAN/INN) 5-HT2C-receptor [HSA:3358] [KO:K04157] Ritanserin D05738 Rita

  3. Serotonergic Hallucinogens as Translational Models Relevant to Schizophrenia

    OpenAIRE

    Halberstadt, Adam L.; Geyer, Mark A.

    2013-01-01

    One of the oldest models of schizophrenia is based on the effects of serotonergic hallucinogens such as mescaline, psilocybin, and (+)-lysergic acid diethylamide (LSD), which act through the serotonin 5-HT2A receptor. These compounds produce a “model psychosis” in normal individuals that resembles at least some of the positive symptoms of schizophrenia. Based on these similarities, and because evidence has emerged that the serotonergic system plays a role in the pathogenesis of schizophrenia ...

  4. Personality, psychopathology, life attitudes and neuropsychological performance among ritual users of ayahuasca: a longitudinal study

    OpenAIRE

    José Carlos Bouso; Débora González; Sabela Fondevila; Marta Cutchet; Xavier Fernández; Paulo César Ribeiro Barbosa; Miguel Ángel Alcázar-Córcoles; Wladimyr Sena Araújo; Manel J Barbanoj; Josep Maria Fábregas; Jordi Riba

    2012-01-01

    Ayahuasca is an Amazonian psychoactive plant beverage containing the serotonergic 5-HT(2A) agonist N,N-dimethyltryptamine (DMT) and monoamine oxidase-inhibiting alkaloids (harmine, harmaline and tetrahydroharmine) that render it orally active. Ayahuasca ingestion is a central feature in several Brazilian syncretic churches that have expanded their activities to urban Brazil, Europe and North America. Members of these groups typically ingest ayahuasca at least twice per month. Prior research h...

  5. Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats

    OpenAIRE

    Vanessa Manchim Favaro; Maurício Yonamine; Juliana Carlota Kramer Soares; Maria Gabriela Menezes de Oliveira

    2015-01-01

    Ayahuasca is a hallucinogenic beverage that combines the action of the 5-HT2A/2C agonist N,N-dimethyltryptamine (DMT) from Psychotria viridis with the monoamine oxidase inhibitors (MAOIs) induced by beta-carbonyls from Banisteriopsis caapi. Previous investigations have highlighted the involvement of ayahuasca with the activation of brain regions known to be involved with episodic memory, contextual associations and emotional processing after ayahuasca ingestion. Moreover long term users show ...

  6. Daytime Ayahuasca administration modulates REM and slow-wave sleep in healthy volunteers

    OpenAIRE

    Manel J Barbanoj; Riba, J.; Clos, S; Gimenez, S.; Grasa, E; Romero Lafuente, Sergio

    2008-01-01

    Ayahuasca is a traditional South American psychoactive beverage and the central sacrament of Brazilianbased religious groups, with followers in Europe and the United States. The tea contains the psychedelic indole N, N-dimethyltryptamine (DMT) and β-carboline alkaloids with monoamine oxidase-inhibiting properties that render DMT orally active. DMT interacts with serotonergic neurotransmission acting as a partial agonist at 5-HT1A and 5-HT2A/2C receptor sites. Given the...

  7. Differential contributions of serotonin receptors to the behavioral effects of indoleamine hallucinogens in mice

    OpenAIRE

    Halberstadt, Adam L.; Koedood, Liselore; Powell, Susan B.; GEYER, Mark A

    2010-01-01

    Psilocin (4-hydroxy-N,N-dimethyltryptamine) is a hallucinogen that acts as an agonist at 5-HT1A, 5-HT2A, and 5-HT2C receptors. Psilocin is the active metabolite of psilocybin, a hallucinogen that is currently being investigated clinically as a potential therapeutic agent. In the present investigation, we used a combination of genetic and pharmacological approaches to identify the serotonin (5-HT) receptor subtypes responsible for mediating the effects of psilocin on head twitch response (HTR)...

  8. Suppressive effect of mitragynine on the 5-methoxy-N,N-dimethyltryptamine-induced head-twitch response in mice.

    Science.gov (United States)

    Matsumoto, K; Mizowaki, M; Takayama, H; Sakai, S; Aimi, N; Watanabe, H

    1997-01-01

    We investigated the effects of mitragynine, a major alkaloid isolated from the leaves of Mitragyna speciosa Korth (Rubiaceae), on the 5-HT2A receptor-mediated head-twitch response in mice. Intraperitoneal injection of mitragynine (5-30 mg/kg), as well as intraperitoneal injection of 5-HT2A receptor antagonist ritanserin, inhibited the 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT: 16 mg/kg, IP)-induced head-twitch response in a dose-dependent manner. In contrast, mitragynine affected neither head-weaving caused by 5-MeO-DMT, nor drug-free spontaneous motor activity. Pretreatment of mice with reserpine (5 mg/kg, IP), p-chlorophenylalanine (p-CPA, 300 mg/kg x 3 times, IP), or 6-hydroxydopamine (6-OHDA, 50 micrograms/mouse, ICV) plus nomifensine (5 mg/kg, IP) did not change the suppressant effect of mitragynine on the head-twitch response caused by 5-MeO-DMT. On the other hand, the alpha 2-adrenoceptor antagonists yohimbine (0.5 mg/kg, IP), and idazoxan (0.2 mg/kg, IP), significantly attenuated the suppressant effect of mitragynine. Lesion of central noradrenergic systems by 6-OHDA plus nomifensine did not alter the effect of idazoxan (0.2 mg/kg) on mitragynine-induced suppression of the head-twitch response. These results indicate that stimulation of postsynaptic alpha 2-adrenoceptor, blockade of 5-HT2A receptors, or both, are involved in suppression of 5-HT2A receptor-mediated head-twitch response by mitragynine. PMID:9164589

  9. 5-HT2A and mGlu2 receptor binding levels are related to differences in impulsive behavior in the Roman Low- (RLA) and High- (RHA) avoidance rat strains

    DEFF Research Database (Denmark)

    Klein, A B; Ultved, L; Adamsen, D;

    2014-01-01

    serotonin transporter (SERT), 5-HT(2A) and 5-HT(1A) receptor binding using highly specific radioligands ((3)H-escitalopram, (3)H-MDL100907 and (3)H-WAY100635) and mGlu2/3 receptor binding ((3)H-LY341495) using receptor autoradiography in fronto-cortical sections from RLA-I (n=8) and RHA-I (n=8) male rats...

  10. Serotonin 2A Receptors Differentially Contribute to Abuse-Related Effects of Cocaine and Cocaine-Induced Nigrostriatal and Mesolimbic Dopamine Overflow in Nonhuman Primates

    OpenAIRE

    Murnane, Kevin S.; Winschel, Jake; Schmidt, Karl T.; Stewart, LaShaya M.; Rose, Samuel J.; Cheng, Kejun; Rice, Kenner C.; Howell, Leonard L.

    2013-01-01

    Two of the most commonly used procedures to study the abuse-related effects of drugs in laboratory animals are intravenous drug self-administration and reinstatement of extinguished behavior previously maintained by drug delivery. Intravenous self-administration is widely accepted to model ongoing drug-taking behavior, whereas reinstatement procedures are accepted to model relapse to drug taking following abstinence. Previous studies indicate that 5-HT2A receptor antagonists attenuate the rei...

  11. Effects of serotonin 2A/1A receptor stimulation on social exclusion processing

    Science.gov (United States)

    Preller, Katrin H.; Pokorny, Thomas; Hock, Andreas; Kraehenmann, Rainer; Stämpfli, Philipp; Seifritz, Erich; Scheidegger, Milan; Vollenweider, Franz X.

    2016-01-01

    Social ties are crucial for physical and mental health. However, psychiatric patients frequently encounter social rejection. Moreover, an increased reactivity to social exclusion influences the development, progression, and treatment of various psychiatric disorders. Nevertheless, the neuromodulatory substrates of rejection experiences are largely unknown. The preferential serotonin (5-HT) 2A/1A receptor agonist, psilocybin (Psi), reduces the processing of negative stimuli, but whether 5-HT2A/1A receptor stimulation modulates the processing of negative social interactions remains unclear. Therefore, this double-blind, randomized, counterbalanced, cross-over study assessed the neural response to social exclusion after the acute administration of Psi (0.215 mg/kg) or placebo (Pla) in 21 healthy volunteers by using functional magnetic resonance imaging (fMRI) and resting-state magnetic resonance spectroscopy (MRS). Participants reported a reduced feeling of social exclusion after Psi vs. Pla administration, and the neural response to social exclusion was decreased in the dorsal anterior cingulate cortex (dACC) and the middle frontal gyrus, key regions for social pain processing. The reduced neural response in the dACC was significantly correlated with Psi-induced changes in self-processing and decreased aspartate (Asp) content. In conclusion, 5-HT2A/1A receptor stimulation with psilocybin seems to reduce social pain processing in association with changes in self-experience. These findings may be relevant to the normalization of negative social interaction processing in psychiatric disorders characterized by increased rejection sensitivity. The current results also emphasize the importance of 5-HT2A/1A receptor subtypes and the Asp system in the control of social functioning, and as prospective targets in the treatment of sociocognitive impairments in psychiatric illnesses. PMID:27091970

  12. Modulatory effect of the 5-HT1A agonist buspirone and the mixed non-hallucinogenic 5-HT1A/2A agonist ergotamine on psilocybin-induced psychedelic experience.

    Science.gov (United States)

    Pokorny, Thomas; Preller, Katrin H; Kraehenmann, Rainer; Vollenweider, Franz X

    2016-04-01

    The mixed serotonin (5-HT) 1A/2A/2B/2C/6/7 receptor agonist psilocybin dose-dependently induces an altered state of consciousness (ASC) that is characterized by changes in sensory perception, mood, thought, and the sense of self. The psychological effects of psilocybin are primarily mediated by 5-HT2A receptor activation. However, accumulating evidence suggests that 5-HT1A or an interaction between 5-HT1A and 5-HT2A receptors may contribute to the overall effects of psilocybin. Therefore, we used a double-blind, counterbalanced, within-subject design to investigate the modulatory effects of the partial 5-HT1A agonist buspirone (20mg p.o.) and the non-hallucinogenic 5-HT2A/1A agonist ergotamine (3mg p.o.) on psilocybin-induced (170 µg/kg p.o.) psychological effects in two groups (n=19, n=17) of healthy human subjects. Psychological effects were assessed using the Altered State of Consciousness (5D-ASC) rating scale. Buspirone significantly reduced the 5D-ASC main scale score for Visionary Restructuralization (VR) (ppsilocybin-induced 5D-ASC main scale scores. The present finding demonstrates that buspirone exerts inhibitory effects on psilocybin-induced effects, presumably via 5-HT1A receptor activation, an interaction between 5-HT1A and 5-HT2A receptors, or both. The data suggest that the modulation of 5-HT1A receptor activity may be a useful target in the treatment of visual hallucinations in different psychiatric and neurological diseases.

  13. Serotonin Transporter and Receptor Expression in Osteocytic MLO-Y4 Cells

    OpenAIRE

    BLIZIOTES, M.; ESHLEMAN, A.; BURT-PICHAT, B.; Zhang, X.-W.; Hashimoto, J; WIREN, K.; C. Chenu

    2006-01-01

    Neurotransmitter regulation of bone metabolism has been a subject of increasing interest and investigation. We reported previously that osteoblastic cells express a functional serotonin (5-HT) signal transduction system, with mechanisms for responding to and regulating uptake of 5-HT. The clonal murine osteocytic cell line, MLO-Y4, demonstrates expression of the serotonin transporter (5-HTT), and the 5-HT1A, and 5-HT2A receptors by real-time RT-PCR and immunoblot analysis. Immunohistochemistr...

  14. Modulatory effect of the 5-HT1A agonist buspirone and the mixed non-hallucinogenic 5-HT1A/2A agonist ergotamine on psilocybin-induced psychedelic experience.

    Science.gov (United States)

    Pokorny, Thomas; Preller, Katrin H; Kraehenmann, Rainer; Vollenweider, Franz X

    2016-04-01

    The mixed serotonin (5-HT) 1A/2A/2B/2C/6/7 receptor agonist psilocybin dose-dependently induces an altered state of consciousness (ASC) that is characterized by changes in sensory perception, mood, thought, and the sense of self. The psychological effects of psilocybin are primarily mediated by 5-HT2A receptor activation. However, accumulating evidence suggests that 5-HT1A or an interaction between 5-HT1A and 5-HT2A receptors may contribute to the overall effects of psilocybin. Therefore, we used a double-blind, counterbalanced, within-subject design to investigate the modulatory effects of the partial 5-HT1A agonist buspirone (20mg p.o.) and the non-hallucinogenic 5-HT2A/1A agonist ergotamine (3mg p.o.) on psilocybin-induced (170 µg/kg p.o.) psychological effects in two groups (n=19, n=17) of healthy human subjects. Psychological effects were assessed using the Altered State of Consciousness (5D-ASC) rating scale. Buspirone significantly reduced the 5D-ASC main scale score for Visionary Restructuralization (VR) (pergotamine did not show any effects on the psilocybin-induced 5D-ASC main scale scores. The present finding demonstrates that buspirone exerts inhibitory effects on psilocybin-induced effects, presumably via 5-HT1A receptor activation, an interaction between 5-HT1A and 5-HT2A receptors, or both. The data suggest that the modulation of 5-HT1A receptor activity may be a useful target in the treatment of visual hallucinations in different psychiatric and neurological diseases. PMID:26875114

  15. Effect of tryptophan hydroxylase-2 gene polymorphism G-703 T on personality in a population representative sample.

    Science.gov (United States)

    Lehto, Kelli; Vaht, Mariliis; Mäestu, Jarek; Veidebaum, Toomas; Harro, Jaanus

    2015-03-01

    The tryptophan hydroxylase-2 gene (TPH2) is coding for the key enzyme of serotonin (5-HT) synthesis in the brain and has been associated with a number of psychiatric conditions. A functional variation in the TPH2 gene (G-703T, rs4570625) has been found to affect anxiety-related personality; however, information is very limited regarding the five factor model (FFM) personality traits. We have examined the association of the TPH2 G-703T polymorphism with FFM personality traits, and the possible modulation by the functional variation in the serotonin transporter gene (5-HTTLPR) in a large longitudinal population representative sample. The FFM personality traits were assessed in both birth cohorts of the Estonian Children Personality Behaviour and Health Study at ages 15 (n=742) and 18 (n=834). Significant association of the TPH2 genotype with Neuroticism and Conscientiousness was found at age 15, and with Extraversion and Conscientiousness at age 18. Participants with the T/T genotype scored significantly lower on Neuroticism and higher on Conscientiousness and Extraversion scales. In addition, a gene×gene interaction effect on Conscientiousness was revealed: the TPH2 genotype effect was evident only in the 5-HTTLPR S-allele carriers. These results provide further evidence on the possible role of genetic variations in 5-HT neurotransmission on development of personality traits, and suggest a functional interaction between two key proteins in the 5-HT-ergic system.

  16. Serotonin Is a Key Factor for Mouse Red Blood Cell Survival

    Science.gov (United States)

    Amireault, Pascal; Bayard, Elisa; Launay, Jean-Marie; Sibon, David; Le Van Kim, Caroline; Colin, Yves; Dy, Michel; Hermine, Olivier; Côté, Francine

    2013-01-01

    Serotonin (5-HT) is a monoamine originally purified from blood as a vasoactive agent. In nonneuronal tissues, its presence is linked with the expression of tryptophan hydroxylase 1 (TPH1) that catalyzes the rate-limiting step of its synthesis. Targeted disruption in mice of the TPH1 gene results in very low levels of circulating 5-HT. Previous analysis of the TPH1 knockout (TPH1−/−) mouse revealed that they develop a phenotype of macrocytic anemia with a reduced half-life of their circulating red blood cells (RBC). In this study, to establish whether the observed reduced half-life of TPH1−/− RBC is an intrinsic or an extrinsic characteristic, we compared their survival to RBC isolated from wild-type mice. Both in vivo and in vitro data converge to demonstrate an extrinsic protective effect of 5-HT since presence of 5-HT in the RBC environment protects RBC from senescence. The protective effect played by 5-HT is not mediated through activation of a classical pharmacological pathway as no 5-HT receptors were detected on isolated RBC. Rather, 5-HT acts as an effective antioxidant since reduction of 5-HT circulating levels are associated with a decrease in the plasma antioxidant capacity. We further demonstrate a link between oxidation and the removal of damaged RBC following transfusion, as supplementation with 5-HT improves RBC post-transfusion survival in a mouse model of blood banking. PMID:24358245

  17. Influence of exercise on serotonergic neuromodulation in the brain.

    Science.gov (United States)

    Weicker, H; Strüder, H K

    2001-01-01

    Implications of exercise on serotonergic neuromodulation in the brain have been investigated in two studies. Acute paroxetine (selective serotonin (5-HT) reuptake inhibitor) administration to endurance athletes, who performed a cycle ergometer test to exhaustion at moderate intensity, reduced time to exhaustion and post exercise cognitive performance in comparison to trials with placebo or BCAA administration. Furthermore, during a 3-week moderate endurance training of sedentary males basaline values of Bmax of 5-HT transporters (5-HTT) and 5-HT2A receptors (5-HT(2A)R) on isolated platelet membranes increased while plasma prolactin (PRL) concentrations decreased as well as mood and physical efficiency improved. In contrast, after an excessive training program over four weeks, well-trained endurance athletes showed no change of Bmax of 5-HTT, but a decline of 5-HT(2A)R density and an increase in basal plasma PRL concentration. Mood was impaired and central fatigue increased. Thus, the impact of exercise on 5-HT neurotransmission may depend on training state of athletes and extent of exertion. The theoretical background of the implication of exercise and the effect of long lasting exhaustive exercise in athletes on mental and physical efficiency or central fatigue are evaluated. The significance of the primary disturbance of central neuromodulation and dysfunction of 5-HTT, 5-HT receptor subtypes and the phosphoinositol signal transduction as well as the limited modulation capacity of the 5-HT system in overstrain are also addressed. PMID:11310929

  18. Serotonin 2A receptor agonist binding in the human brain with [11C]Cimbi-36

    DEFF Research Database (Denmark)

    Ettrup, Anders; Svarer, Claus; McMahon, Brenda;

    2016-01-01

    ]Cimbi-36 and the 5-HT2A receptor antagonist [(18)F]altanserin. METHODS: Sixteen healthy volunteers (mean age 23.9 ± 6.4years, 6 males) were scanned twice with a high resolution research tomography PET scanner. All subjects were scanned after a bolus of [(11)C]Cimbi-36; eight were scanned twice to determine...... BPNDs measured with [(11)C]Cimbi-36 and [(18)F]altanserin (mean Pearson's r: 0.95 ± 0.04) suggesting similar cortical binding of the radioligands. Relatively higher binding with [(11)C]Cimbi-36 as compared to [(18)F]altanserin was found in the choroid plexus and hippocampus in the human brain....... CONCLUSIONS: Excellent test-retest reproducibility highlights the potential of [(11)C]Cimbi-36 for PET imaging of 5-HT2A receptor agonist binding in vivo. Our data suggest that Cimbi-36 and altanserin both bind to 5-HT2A receptors, but in regions with high 5-HT2C receptor density, choroid plexus...

  19. Synthesis and evaluation of a series of 2-substituted-5-thiopropylpiperazine (piperidine-1,3,4-oxadiazoles derivatives as atypical antipsychotics.

    Directory of Open Access Journals (Sweden)

    Yin Chen

    Full Text Available BACKGROUND: It is important to develop novel antipsychotics that can effectively treat schizophrenia with minor side-effects. The aim of our work is to develop novel antipsychotics that act on dopamine D(2 and D(3, serotonin 5-HT(1A and 5-HT(2A receptors with low affinity for the serotonin 5-HT(2C and H(1 receptors, which can effectively cure positive symptoms, negative symptoms and cognitive impairment without the weight gain side-effect. METHODOLOGY/PRINCIPAL FINDINGS: A series of 2-substituted-5-thiopropylpiperazine (piperidine -1,3,4-oxadiazoles derivatives have been synthesized and the target compounds were evaluated for binding affinities to D(2, 5-HT(1A and 5-HT(2A receptors. Preliminary results indicated that compounds 14, 16 and 22 exhibited high affinities to D(2, 5-HT(1A and 5-HT(2A receptors among these compounds. Further binding tests showed that compound 22 had high affinity for D(3 receptor, and low affinity for serotonin 5-HT(2C and H(1 receptors. In addition, compound 22 inhibited apomorphine-induced climbing behavior and MK-801-induced hyperactivity with no extrapyramidal symptoms liability in mice. Moreover, compound 22 exhibited acceptable pharmacokinetic properties. CONCLUSIONS/SIGNIFICANCE: Compound 22 showed an atypical antipsychotic activity without liability for extrapyramidal symptoms. We anticipate compound 22 to be useful for developing a novel class of drug for the treatment of schizophrenia.

  20. Aromatic interactions impact ligand binding and function at serotonin 5-HT2C G protein-coupled receptors: receptor homology modelling, ligand docking, and molecular dynamics results validated by experimental studies

    Science.gov (United States)

    Córdova-Sintjago, Tania; Villa, Nancy; Fang, Lijuan; Booth, Raymond G.

    2014-02-01

    The serotonin (5-hydroxytryptamine, 5-HT) 5-HT2 G protein-coupled receptor (GPCR) family consists of types 2A, 2B, and 2C that share ∼75% transmembrane (TM) sequence identity. Agonists for 5-HT2C receptors are under development for psychoses; whereas, at 5-HT2A receptors, antipsychotic effects are associated with antagonists - in fact, 5-HT2A agonists can cause hallucinations and 5-HT2B agonists cause cardiotoxicity. It is known that 5-HT2A TM6 residues W6.48, F6.51, and F6.52 impact ligand binding and function; however, ligand interactions with these residues at the 5-HT2C receptor have not been reported. To predict and validate molecular determinants for 5-HT2C-specific activation, results from receptor homology modelling, ligand docking, and molecular dynamics simulation studies were compared with experimental results for ligand binding and function at wild type and W6.48A, F6.51A, and F6.52A point-mutated 5-HT2C receptors.

  1. Behavioral and pharmacokinetic interactions between monoamine oxidase inhibitors and the hallucinogen 5-methoxy-N,N-dimethyltryptamine.

    Science.gov (United States)

    Halberstadt, Adam L

    2016-04-01

    Monoamine oxidase inhibitors (MAOIs) are often ingested together with tryptamine hallucinogens, but relatively little is known about the consequences of their combined use. We have shown previously that monoamine oxidase-A (MAO-A) inhibitors alter the locomotor profile of the hallucinogen 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) in rats, and enhance its interaction with 5-HT2A receptors. The goal of the present studies was to investigate the mechanism for the interaction between 5-MeO-DMT and MAOIs, and to determine whether other behavioral responses to 5-MeO-DMT are similarly affected. Hallucinogens disrupt prepulse inhibition (PPI) in rats, an effect typically mediated by 5-HT2A activation. 5-MeO-DMT also disrupts PPI but the effect is primarily attributable to 5-HT1A activation. The present studies examined whether an MAOI can alter the respective contributions of 5-HT1A and 5-HT2A receptors to the effects of 5-MeO-DMT on PPI. A series of interaction studies using the 5-HT1A antagonist WAY-100,635 and the 5-HT2A antagonist MDL 11,939 were performed to assess the respective contributions of these receptors to the behavioral effects of 5-MeO-DMT in rats pretreated with an MAOI. The effects of MAO-A inhibition on the pharmacokinetics of 5-MeO-DMT and its metabolism to bufotenine were assessed using liquid chromatography-electrospray ionization-selective reaction monitoring-tandem mass spectrometry (LC-ESI-SRM-MS/MS). 5-MeO-DMT (1mg/kg) had no effect on PPI when tested 45-min post-injection but disrupted PPI in animals pretreated with the MAO-A inhibitor clorgyline or the MAO-A/B inhibitor pargyline. The combined effect of 5-MeO-DMT and pargyline on PPI was antagonized by pretreatment with either WAY-100,635 or MDL 11,939. Inhibition of MAO-A increased the level of 5-MeO-DMT in plasma and whole brain, but had no effect on the conversion of 5-MeO-DMT to bufotenine, which was found to be negligible. The present results confirm that 5-MeO-DMT can disrupt PPI by

  2. Differential contributions of serotonin receptors to the behavioral effects of indoleamine hallucinogens in mice.

    Science.gov (United States)

    Halberstadt, Adam L; Koedood, Liselore; Powell, Susan B; Geyer, Mark A

    2011-11-01

    Psilocin (4-hydroxy-N,N-dimethyltryptamine) is a hallucinogen that acts as an agonist at 5-HT(1A), 5-HT(2A), and 5-HT(2C) receptors. Psilocin is the active metabolite of psilocybin, a hallucinogen that is currently being investigated clinically as a potential therapeutic agent. In the present investigation, we used a combination of genetic and pharmacological approaches to identify the serotonin (5-HT) receptor subtypes responsible for mediating the effects of psilocin on head twitch response (HTR) and the behavioral pattern monitor (BPM) in C57BL/6J mice. We also compared the effects of psilocin with those of the putative 5-HT(2C) receptor-selective agonist 1-methylpsilocin and the hallucinogen and non-selective serotonin receptor agonist 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT). Psilocin, 1-methylpsilocin, and 5-MeO-DMT induced the HTR, effects that were absent in mice lacking the 5-HT(2A) receptor gene. When tested in the BPM, psilocin decreased locomotor activity, holepoking, and time spent in the center of the chamber, effects that were blocked by the selective 5-HT(1A) antagonist WAY-100635 but were not altered by the selective 5-HT(2C) antagonist SB 242,084 or by 5-HT(2A) receptor gene deletion. 5-MeO-DMT produced similar effects when tested in the BPM, and the action of 5-MeO-DMT was significantly attenuated by WAY-100635. Psilocin and 5-MeO-DMT also decreased the linearity of locomotor paths, effects that were mediated by 5-HT(2C) and 5-HT(1A) receptors, respectively. In contrast to psilocin and 5-MeO-DMT, 1-methylpsilocin (0.6-9.6 mg/kg) was completely inactive in the BPM. These findings confirm that psilocin acts as an agonist at 5-HT(1A), 5-HT(2A), and 5-HT(2C) receptors in mice, whereas the behavioral effects of 1-methylpsilocin indicate that this compound is acting at 5-HT(2A) sites but is inactive at the 5-HT(1A) receptor. The fact that 1-methylpsilocin displays greater pharmacological selectivity than psilocin indicates that 1-methylpsilocin

  3. Tetracycline inducible gene manipulation in serotonergic neurons.

    Directory of Open Access Journals (Sweden)

    Tillmann Weber

    Full Text Available The serotonergic (5-HT neuronal system has important and diverse physiological functions throughout development and adulthood. Its dysregulation during development or later in adulthood has been implicated in many neuropsychiatric disorders. Transgenic animal models designed to study the contribution of serotonergic susceptibility genes to a pathological phenotype should ideally allow to study candidate gene overexpression or gene knockout selectively in serotonergic neurons at any desired time during life. For this purpose, conditional expression systems such as the tet-system are preferable. Here, we generated a transactivator (tTA mouse line (TPH2-tTA that allows temporal and spatial control of tetracycline (Ptet controlled transgene expression as well as gene deletion in 5-HT neurons. The tTA cDNA was inserted into a 196 kb PAC containing a genomic mouse Tph2 fragment (177 kb by homologous recombination in E. coli. For functional analysis of Ptet-controlled transgene expression, TPH2-tTA mice were crossed to a Ptet-regulated lacZ reporter line (Ptet-nLacZ. In adult double-transgenic TPH2-tTA/Ptet-nLacZ mice, TPH2-tTA founder line L62-20 showed strong serotonergic β-galactosidase expression which could be completely suppressed with doxycycline (Dox. Furthermore, Ptet-regulated gene expression could be reversibly activated or inactivated when Dox was either withdrawn or added to the system. For functional analysis of Ptet-controlled, Cre-mediated gene deletion, TPH2-tTA mice (L62-20 were crossed to double transgenic Ptet-Cre/R26R reporter mice to generate TPH2-tTA/Ptet-Cre/R26R mice. Without Dox, 5-HT specific recombination started at E12.5. With permanent Dox administration, Ptet-controlled Cre-mediated recombination was absent. Dox withdrawal either postnatally or during adulthood induced efficient recombination in serotonergic neurons of all raphe nuclei, respectively. In the enteric nervous system, recombination could not be detected. We

  4. Pyrrolo[1,3]benzothiazepine-based serotonin and dopamine receptor antagonists. Molecular modeling, further structure-activity relationship studies, and identification of novel atypical antipsychotic agents.

    Science.gov (United States)

    Campiani, Giuseppe; Butini, Stefania; Fattorusso, Caterina; Catalanotti, Bruno; Gemma, Sandra; Nacci, Vito; Morelli, Elena; Cagnotto, Alfredo; Mereghetti, Ilario; Mennini, Tiziana; Carli, Miriana; Minetti, Patrizia; Di Cesare, M Assunta; Mastroianni, Domenico; Scafetta, Nazzareno; Galletti, Bruno; Stasi, M Antonietta; Castorina, Massimo; Pacifici, Licia; Vertechy, Mario; Di Serio, Stefano; Ghirardi, Orlando; Tinti, Ornella; Carminati, Paolo

    2004-01-01

    Recently we reported the pharmacological characterization of the 9,10-dihydropyrrolo[1,3]benzothiazepine derivative (S)-(+)-8 as a novel atypical antipsychotic agent. This compound had an optimum pK(i) 5-HT(2A)/D(2) ratio of 1.21 (pK(i) 5-HT(2A) = 8.83; pK(i) D(2) = 7.79). The lower D(2) receptor affinity of (S)-(+)-8 compared to its enantiomer was explained by the difficulty in reaching the conformation required to optimally fulfill the D(2) pharmacophore. With the aim of finding novel atypical antipsychotics we further investigated the core structure of (S)-(+)-8, synthesizing analogues with specific substituents; the structure-activity relationship (SAR) study was also expanded with the design and synthesis of other analogues characterized by a pyrrolo[2,1-b][1,3]benzothiazepine skeleton, substituted on the benzo-fused ring or on the pyrrole system. On the 9,10-dihydro analogues the substituents introduced on the pyrrole ring were detrimental to affinity for dopamine and for 5-HT(2A) receptors, but the introduction of a double bond at C-9/10 on the structure of (S)-(+)-8 led to a potent D(2)/5-HT(2A) receptor ligand with a typical binding profile (9f, pK(i) 5-HT(2A)/D(2) ratio of 1.01, log Y = 8.43). Then, to reduce D(2) receptor affinity and restore atypicality on unsaturated analogues, we exploited the effect of specific substitutions on the tricyclic system of 9f. Through a molecular modeling approach we generated a novel series of potential atypical antipsychotic agents, with optimized 5HT(2A)/D(2) receptor affinity ratios and that were easier to synthesize and purify than the reference compound (S)-(+)-8. A number of SAR trends were identified, and among the analogues synthesized and tested in binding assays, 9d and 9m were identified as the most interesting, giving atypical log Y scores respectively 4.98 and 3.18 (pK(i) 5-HT(2A)/D(2) ratios of 1.20 and 1.30, respectively). They had a multireceptor affinity profile and could be promising atypical agents

  5. Metabolomics Approach Reveals Integrated Metabolic Network Associated with Serotonin Deficiency

    Science.gov (United States)

    Weng, Rui; Shen, Sensen; Tian, Yonglu; Burton, Casey; Xu, Xinyuan; Liu, Yi; Chang, Cuilan; Bai, Yu; Liu, Huwei

    2015-07-01

    Serotonin is an important neurotransmitter that broadly participates in various biological processes. While serotonin deficiency has been associated with multiple pathological conditions such as depression, schizophrenia, Alzheimer’s disease and Parkinson’s disease, the serotonin-dependent mechanisms remain poorly understood. This study therefore aimed to identify novel biomarkers and metabolic pathways perturbed by serotonin deficiency using metabolomics approach in order to gain new metabolic insights into the serotonin deficiency-related molecular mechanisms. Serotonin deficiency was achieved through pharmacological inhibition of tryptophan hydroxylase (Tph) using p-chlorophenylalanine (pCPA) or genetic knockout of the neuronal specific Tph2 isoform. This dual approach improved specificity for the serotonin deficiency-associated biomarkers while minimizing nonspecific effects of pCPA treatment or Tph2 knockout (Tph2-/-). Non-targeted metabolic profiling and a targeted pCPA dose-response study identified 21 biomarkers in the pCPA-treated mice while 17 metabolites in the Tph2-/- mice were found to be significantly altered compared with the control mice. These newly identified biomarkers were associated with amino acid, energy, purine, lipid and gut microflora metabolisms. Oxidative stress was also found to be significantly increased in the serotonin deficient mice. These new biomarkers and the overall metabolic pathways may provide new understanding for the serotonin deficiency-associated mechanisms under multiple pathological states.

  6. Serotonin and Early Cognitive Development: Variation in the Tryptophan Hydroxylase 2 Gene Is Associated with Visual Attention in 7-Month-Old Infants

    Science.gov (United States)

    Leppanen, Jukka M.; Peltola, Mikko J.; Puura, Kaija; Mantymaa, Mirjami; Mononen, Nina; Lehtimaki, Terho

    2011-01-01

    Background: Allelic variation in the promoter region of a gene that encodes tryptophan hydroxylase isoform 2 (TPH2), a rate-limiting enzyme of serotonin synthesis in the central nervous system, has been associated with variations in cognitive function and vulnerability to affective spectrum disorders. Little is known about the effects of this gene…

  7. Association between tryptophan hydroxylase-2 genotype and the antidepressant effect of citalopram and paroxetine on immobility time in the forced swim test in mice.

    Science.gov (United States)

    Kulikov, Alexander V; Tikhonova, Maria A; Osipova, Daria V; Kulikov, Victor A; Popova, Nina K

    2011-10-01

    Tryptophan hydroxylase-2 (TPH2) is the rate limiting enzyme of serotonin synthesis in the brain. The 1473G allele of the C1473G polymorphism in mTPH2 gene is associated with reduced enzyme activity and serotonin synthesis rate in the mouse brain. Here, the influence of the 1473G allele on the antidepressant effect of selective serotonin reuptake inhibitors (SSRIs), citalopram (2.5 or 5.0mg/kg) and paroxetine (5.0 or 10.0mg/kg), in the forced swim test was studied using B6-1473G and B6-1473C congenic mouse lines with the 1473G (decreased TPH2 activity) or 1473C (normal TPH2 activity) alleles, respectively, transferred to the genome of C57BL/6 mouse strain. Paroxetine (5.0 or 10.0mg/kg) and citalopram (2.5 or 5.0mg/kg) decreased immobility time in B6-1473C mice, while both doses of paroxetine and 2.5mg/kg of citaloprame did not alter immobility time in B6-1473G mice. However, 5.0mg/kg of citalopram reduced immobility in B6-1473G mice. The results provided genetic evidence of moderate association between 1473G allele and reduced sensitivity to SSRIs in mice.

  8. Serotonin control of thermotaxis memory behavior in nematode Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Yinxia Li

    Full Text Available Caenorhabditis elegans is as an ideal model system for the study of mechanisms underlying learning and memory. In the present study, we employed C. elegans assay system of thermotaxis memory to investigate the possible role of serotonin neurotransmitter in memory control. Our data showed that both mutations of tph-1, bas-1, and cat-4 genes, required for serotonin synthesis, and mutations of mod-5 gene, encoding a serotonin reuptake transporter, resulted in deficits in thermotaxis memory behavior. Exogenous treatment with serotonin effectively recovered the deficits in thermotaxis memory of tph-1 and bas-1 mutants to the level of wild-type N2. Neuron-specific activity assay of TPH-1 suggests that serotonin might regulate the thermotaxis memory behavior by release from the ADF sensory neurons. Ablation of ADF sensory neurons by expressing a cell-death activator gene egl-1 decreased the thermotaxis memory, whereas activation of ADF neurons by expression of a constitutively active protein kinase C homologue (pkc-1(gf increased the thermotaxis memory and rescued the deficits in thermotaxis memory in tph-1 mutants. Moreover, serotonin released from the ADF sensory neurons might act through the G-protein-coupled serotonin receptors of SER-4 and SER-7 to regulate the thermotaxis memory behavior. Genetic analysis implies that serotonin might further target the insulin signaling pathway to regulate the thermotaxis memory behavior. Thus, our results suggest the possible crucial role of serotonin and ADF sensory neurons in thermotaxis memory control in C. elegans.

  9. Mechanism of Inhibition of Novel Tryptophan Hydroxylase Inhibitors Revealed by Co-crystal Structures and Kinetic Analysis.

    Science.gov (United States)

    Cianchetta, Giovanni; Stouch, Terry; Yu, Wangsheng; Shi, Zhi-Cai; Tari, Leslie W; Swanson, Ronald V; Hunter, Michael J; Hoffman, Isaac D; Liu, Qingyun

    2010-01-01

    Trytophan Hydroxylase Type I (TPH1), most abundantly expressed in the gastrointestinal tract, initiates the synthesis of serotonin by catalyzing hydroxylation of tryptophan in the presence of biopterin and oxygen. We have previously described three series of novel, periphery-specific TPH1 inhibitors that selectively deplete serotonin in the gastrointestinal tract. We have now determined co-crystal structures of TPH1 with three of these inhibitors at high resolution. Analysis of the structural data showed that each of the three inhibitors fills the tryptophan binding pocket of TPH1 without reaching into the binding site of the cofactor pterin, and induces major conformational changes of the enzyme. The enzyme-inhibitor complexes assume a compact conformation that is similar to the one in tryptophan complex. Kinetic analysis showed that all three inhibitors are competitive versus the substrate tryptophan, consistent with the structural data that the compounds occupy the tryptophan binding site. On the other hand, all three inhibitors appear to be uncompetitive versus the cofactor 6-methyltetrahydropterin, which is not only consistent with the structural data but also indicate that the hydroxylation reaction follows an ordered binding mechanism in which a productive complex is formed only if tryptophan binds only after pterin, similar to the kinetic mechanisms of tyrosine and phenylalanine hydroxylase.

  10. Transmission disequilibrium of polymorphic variants in the tryptophan hydroxylase-2 gene in children and adolescents with obsessive-compulsive disorder.

    Science.gov (United States)

    Mössner, Rainald; Walitza, Susanne; Geller, Frank; Scherag, André; Gutknecht, Lise; Jacob, Christian; Bogusch, Lisa; Remschmidt, Helmut; Simons, Michael; Herpertz-Dahlmann, Beate; Fleischhaker, Christian; Schulz, Eberhard; Warnke, Andreas; Hinney, Anke; Wewetzer, Christoph; Lesch, Klaus-Peter

    2006-08-01

    Dysfunction of the central serotonergic system has been implicated in the pathophysiology of obsessive-compulsive disorder (OCD). The genetic contribution to the development of OCD is particularly high in early-onset OCD. The aim of this study was to investigate the effect of polymorphic variants in the gene of the novel brain-specific tryptophan hydroxylase-2 (TPH2), the rate-limiting enzyme of serotonin (5-HT) synthesis in the brain, in OCD with disease onset in childhood and adolescence. We analysed two common single nucleotide polymorphisms (SNPs) of TPH2 in the putative transcriptional control region and in intron 2 of the TPH2 gene in a unique family-based sample of OCD patients with onset of the disease in childhood and adolescence comprising 71 complete, independent trios. The transmission disequilibrium test was used to determine transmission of alleles and haplotypes from parents to offspring. In this first study of TPH2 in OCD, analysis of the SNPs, rs4570625 and rs4565946, revealed a significant preferential transmission of haplotype G-C to children and adolescents with OCD. Moreover, a trend towards preferential transmission of the C allele of SNP rs4565946 to the patients was found. The genotype relative-risk estimate for homozygous C allele carriers of SNP rs4565946 was 2.58 (95% CI 0.98-6.82). In conclusion, the results link TPH2 variations to the pathogenesis of early-onset OCD and further support the aetiological relevance of 5-HT signalling in OCD. PMID:16146581

  11. Variations in tryptophan hydroxylase 2 linked to decreased serotonergic activity are associated with elevated risk for metabolic syndrome in depression.

    Science.gov (United States)

    Kloiber, S; Kohli, M A; Brueckl, T; Ripke, S; Ising, M; Uhr, M; Menke, A; Unschuld, P G; Horstmann, S; Salyakina, D; Muller-Myhsok, B; Binder, E B; Holsboer, F; Lucae, S

    2010-07-01

    Major depression and the metabolic syndrome (MetS) are interacting clinical conditions influenced by genetic susceptibility. For both disorders, impaired serotonergic neurotransmission in specific brain areas has been suggested. This led us to investigate whether variants in the gene coding for tryptophan hydroxylase 2 (TPH2), the brain-specific and rate-limiting enzyme for serotonin biosynthesis, might be predictive for an increased liability for the development of MetS in depressed patients. In a case-control study consisting of 988 patients with recurrent unipolar depression (RUD) and 1023 psychiatric healthy controls, MetS components were ascertained according to the International Diabetes Foundation criteria. A total of 41 single nucleotide polymorphisms fully covering the TPH2 gene region were genotyped in stage 1 (300 patients/300 controls), resulting in significant genetic associations of polymorphisms located in exon 7 and intron 8 of TPH2 and the occurrence of MetS in depressed patients after correction for age, gender and multiple testing (51 RUD-MetS/179 RUD-non-MetS). We were able to confirm the significant association of rs17110690 in stage 2 (688 patients/723 controls; 110 RUD-MetS/549 RUD-non-MetS) and to link risk-genotypes and risk-haplotypes for MetS to lower TPH2 mRNA expression and to lower 5-hydroxyindoleacetic acid levels in cerebrospinal fluid previously reported in functional studies. Our findings suggest that TPH2 polymorphisms characterize a subgroup of depressed patients who are especially prone to develop metabolic disorders induced by a genotype-dependent impairment of serotonergic neurotransmission. Identifying depressed patients at high risk for MetS using genetic variants could have direct clinical impact on individualized disease management and prevention strategies. PMID:19125159

  12. The effects of child maltreatment on early signs of antisocial behavior: genetic moderation by tryptophan hydroxylase, serotonin transporter, and monoamine oxidase A genes.

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    Cicchetti, Dante; Rogosch, Fred A; Thibodeau, Eric L

    2012-08-01

    Gene-environment interaction effects in predicting antisocial behavior in late childhood were investigated among maltreated and nonmaltreated low-income children (N = 627, M age = 11.27). Variants in three genes were examined: tryptophan hydroxylase 1 (TPH1), serotonin transporter linked polymorphic region (5-HTTLPR), and monoamine oxidase A (MAOA) upstream variable number tandem repeat. In addition to child maltreatment status, we considered the impact of maltreatment subtypes, developmental timing of maltreatment, and chronicity. Indicators of antisocial behavior were obtained from self-, peer, and adult counselor reports. In a series of analyses of covariance, child maltreatment and its parameters demonstrated strong main effects on early antisocial behavior as assessed by all report forms. Genetic effects operated primarily in the context of gene-environment interactions, moderating the impact of child maltreatment on outcomes. Across the three genes, among nonmaltreated children no differences in antisocial behavior were found based on genetic variation. In contrast, among maltreated children specific polymorphisms of TPH1, 5-HTTLPR, and MAOA were each related to heightened self-report of antisocial behavior; the interaction of 5-HTTLPR and developmental timing of maltreatment also indicated more severe antisocial outcomes for children with early onset and recurrent maltreatment based on genotype. TPH1 and 5-HTTLPR interacted with maltreatment subtype to predict peer reports of antisocial behavior; genetic variation contributed to larger differences in antisocial behavior among abused children. The TPH1 and 5-HTTLPR polymorphisms also moderated the effects of maltreatment subtype on adult reports of antisocial behavior; again, the genetic effects were strongest for children who were abused. In addition, TPH1 moderated the effect of developmental timing of maltreatment and chronicity on adult reports of antisocial behavior. The findings elucidate how genetic

  13. Serotonin Deficiency Rescues Lactation on Day 1 in Mice Fed a High Fat Diet

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    Prichard, Allan S.; Perez, Paola K.; Streckenbach, Liana J.; Olson, Jake M.; Cook, Mark E.; Hernandez, Laura L.

    2016-01-01

    Obesity is an inflammatory state associated with delayed lactogenesis stage II and altered mammary gland morphology. Serotonin mediates inflammation and mammary gland involution. The objective of this study was to determine if a genetic deficiency of tryptophan hydroxylase 1, the rate-limiting enzyme in peripheral serotonin synthesis, would result in an improved ability to lactate in dams fed a high fat diet. Twenty-six female mice were fed a high (HFD) or low fat (LFD) diet throughout pregnancy and lactation. Fourteen mice were genetically deficient for Tph1 (Tph1-/-), and twelve were wild type. Milk yield, pup mortality, and dam weights were recorded and milk samples were collected. On day 10 of lactation, dams were sacrificed and mammary glands were harvested for RT-PCR and histological evaluation. HFD dams weighed more than LFD dams at the onset of lactation. WT HFD dams were unable to lactate on day 1 of lactation and exhibited increased pup mortality relative to all other treatments, including Tph1-/- HFD dams. mRNA expression of immune markers C-X-C motif chemokine 5 and tumor necrosis factor alpha were elevated in WT HFD mammary glands. Mammary gland histology showed a reduced number of alveoli in WT compared to Tph1-/- dams, regardless of diet, and the alveoli of HFD dams were smaller than those of LFD dams. Finally, fatty acid profile in milk was dynamic in both early and peak lactation, with reduced de novo synthesis of fatty acids on day 10 of lactation in the HFD groups. Administration of a HFD to C57BL/6 dams produced an obese phenotype in the mammary gland, which was alleviated by a genetic deficiency of Tph1. Serotonin may modulate the effects of obesity on the mammary gland, potentially contributing to the delayed onset of lactogenesis seen in obese women. PMID:27603698

  14. PET imaging reveals brain functional changes in internet gaming disorder

    International Nuclear Information System (INIS)

    Internet gaming disorder is an increasing problem worldwide, resulting in critical academic, social, and occupational impairment. However, the neurobiological mechanism of internet gaming disorder remains unknown. The aim of this study is to assess brain dopamine D2 (D2)/Serotonin 2A (5-HT2A) receptor function and glucose metabolism in the same subjects by positron emission tomography (PET) imaging approach, and investigate whether the correlation exists between D2 receptor and glucose metabolism. Twelve drug-naive adult males who met criteria for internet gaming disorder and 14 matched controls were studied with PET and 11C-N-methylspiperone (11C-NMSP) to assess the availability of D2/5-HT2A receptors and with 18F-fluoro-D-glucose (18F-FDG) to assess regional brain glucose metabolism, a marker of brain function. 11C-NMSP and 18F-FDG PET imaging data were acquired in the same individuals under both resting and internet gaming task states. In internet gaming disorder subjects, a significant decrease in glucose metabolism was observed in the prefrontal, temporal, and limbic systems. Dysregulation of D2 receptors was observed in the striatum, and was correlated to years of overuse. A low level of D2 receptors in the striatum was significantly associated with decreased glucose metabolism in the orbitofrontal cortex. For the first time, we report the evidence that D2 receptor level is significantly associated with glucose metabolism in the same individuals with internet gaming disorder, which indicates that D2/5-HT2A receptor-mediated dysregulation of the orbitofrontal cortex could underlie a mechanism for loss of control and compulsive behavior in internet gaming disorder subjects. (orig.)

  15. Phospholipase C mediates (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI)-, but not lysergic acid diethylamide (LSD)-elicited head bobs in rabbit medial prefrontal cortex.

    Science.gov (United States)

    Schindler, Emmanuelle A D; Harvey, John A; Aloyo, Vincent J

    2013-01-23

    The phenethylamine and indoleamine classes of hallucinogens demonstrate distinct pharmacological properties, although they share a serotonin(2A) (5-HT(2A)) receptor mechanism of action (MOA). The 5-HT(2A) receptor signals through phosphatidylinositol (PI) hydrolysis, which is initiated upon activation of phospholipase C (PLC). The role of PI hydrolysis in the effects of hallucinogens remains unclear. In order to better understand the role of PI hydrolysis in the MOA of hallucinogens, the PLC inhibitor, 1-[6-((17β-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl]-1H-pyrrole-2,5-dione (U73122), was used to study the effects of two hallucinogens, the phenethylamine, (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), and the indoleamine, lysergic acid diethylamide (LSD). PI hydrolysis was quantified through release of [3H]inositol-4-phosphate from living rabbit frontocortical tissue prisms. Head bobs were counted after hallucinogens were infused into the medial prefrontal cortex (mPFC) of rabbits. Both DOI and LSD stimulated PI hydrolysis in frontocortical tissue through activation of PLC. DOI-stimulated PI hydrolysis was blocked by 5-HT(2A/2C) receptor antagonist, ketanserin, whereas the LSD signal was blocked by 5-HT(2B/2C) receptor antagonist, SB206553. When infused into the mPFC, both DOI- and LSD-elicited head bobs. Pretreatment with U73122 blocked DOI-, but not LSD-elicited head bobs. The two hallucinogens investigated were distinct in their activation of the PI hydrolysis signaling pathway. The serotonergic receptors involved with DOI and LSD signals in frontocortical tissue were different. Furthermore, PLC activation in mPFC was necessary for DOI-elicited head bobs, whereas LSD-elicited head bobs were independent of this pathway. These novel findings urge closer investigation into the intracellular mechanism of action of these unique compounds.

  16. Dual role of endogenous serotonin in 2,4,6-trinitrobenzene sulfonic acid-induced colitis

    Directory of Open Access Journals (Sweden)

    Alberto eRapalli

    2016-03-01

    Full Text Available Background and Aims: Changes in gut serotonin content have been described in Inflammatory Bowel Disease and in different experimental models of colitis: the critical role of this monoamine in the pathogenesis of chronic gastrointestinal inflammation is gradually emerging. Aim of the present study was to evaluate the contribution of endogenous serotonin through the activation of its specific receptor subtypes to the local and systemic inflammatory responses in an experimental model of Inflammatory Bowel Disease. Methods: Colitis was induced by intrarectal 2,4,6-TriNitroBenzene Sulfonic acid in mice subacutely treated with selective antagonists of 5-HT1A (WAY100135, 5-HT2A (Ketanserin, 5-HT3 (Ondansetron, 5-HT4 (GR125487, 5-HT7 (SB269970 receptors and with 5-HT1A agonist 8-Hydroxy-2-(di-n-propylaminotetralin. Results: Blockade of 5-HT1A receptors worsened TNBS-induced local and systemic neutrophil recruitment while 5-HT1A agonist delayed and mitigated the severity of colitis, counteracting the increase in colonic 5-HT content. On the contrary, blockade of 5-HT2A receptors improved global health conditions, reduced colonic morphological alterations, down-regulated neutrophil recruitment, inflammatory cytokines levels and colonic apoptosis. Antagonism of 5-HT3, 5-HT4 and 5-HT7 receptor sites did not remarkably affect the progression and outcome of the pathology or only slightly improved it.Conclusions: The prevailing deleterious contribution given by endogenous serotonin to inflammation in TNBS-induced colitis is seemingly mediated by 5-HT2A and, to a lesser extent, by 5-HT4 receptors and coexists with the weak beneficial effect elicited by 5-HT1A stimulation. These findings suggest how only a selective interference with 5-HT pro-inflammatory actions may represent an additional potential therapeutic option for intestinal inflammatory disorders.

  17. Molecular mechanisms of serotonergic action of the HIV-1 antiretroviral efavirenz.

    Science.gov (United States)

    Dalwadi, Dhwanil A; Kim, Seongcheol; Amdani, Shahnawaz M; Chen, Zhenglan; Huang, Ren-Qi; Schetz, John A

    2016-08-01

    Efavirenz is highly effective at suppressing HIV-1, and the WHO guidelines list it as a component of the first-line antiretroviral (ARV) therapies for treatment-naïve patients. Though the pharmacological basis is unclear, efavirenz is commonly associated with a risk for neuropsychiatric adverse events (NPAEs) when taken at the prescribed dose. In many patients these NPAEs appear to subside after several weeks of treatment, though long-term studies show that in some patients the NPAEs persist. In a recent study focusing on the abuse potential of efavirenz, its receptor psychopharmacology was reported to include interactions with a number of established molecular targets for known drugs of abuse, and it displayed a prevailing behavioral profile in rodents resembling an LSD-like activity. In this report, we discovered interactions with additional serotonergic targets that may be associated with efavirenz-induced NPAEs. The most robust interactions were with 5-HT3A and 5-HT6 receptors, with more modest interactions noted for the 5-HT2B receptor and monoamine oxidase A. From a molecular mechanistic perspective, efavirenz acts as a 5-HT6 receptor inverse agonist of Gs-signaling, 5-HT2A and 5-HT2C antagonist of Gq-signaling, and a blocker of the 5-HT3A receptor currents. Efavirenz also completely or partially blocks agonist stimulation of the M1 and M3 muscarinic receptors, respectively. Schild analysis suggests that efavirenz competes for the same site on the 5-HT2A receptor as two known hallucinogenic partial agonists (±)-DOI and LSD. Prolonged exposure to efavirenz reduces 5-HT2A receptor density and responsiveness to 5-HT. Other ARVs such as zidovudine, nevirapine and emtricitabine did not share the same complex pharmacological profile as efavirenz, though some of them weakly interact with the 5-HT6 receptor or modestly block GABAA currents. PMID:27157251

  18. Multiple receptor subtypes mediate the effects of serotonin on rat subfornical organ neurons

    Science.gov (United States)

    Scrogin, K. E.; Johnson, A. K.; Schmid, H. A.

    1998-01-01

    The subfornical organ (SFO) receives significant serotonergic innervation. However, few reports have examined the functional effects of serotonin on SFO neurons. This study characterized the effects of serotonin on spontaneously firing SFO neurons in the rat brain slice. Of 31 neurons tested, 80% responded to serotonin (1-100 microM) with either an increase (n = 15) or decrease (n = 10) in spontaneous activity. Responses to serotonin were dose dependent and persisted after synaptic blockade. Excitatory responses could also be mimicked by the 5-hydroxytryptamine (5-HT)2A/2C receptor agonist 2,5-dimethoxy-4-iodoamphetamine (DOI; 1-10 microM) and could be blocked by the 5-HT2A/2C-receptor antagonist LY-53,857 (10 microM). LY-53,857 unmasked inhibitory responses to serotonin in 56% of serotonin-excited cells tested. Serotonin-inhibited cells were also inhibited by the 5-HT1A-receptor agonist 8-hydroxy-2(di-n-propylamino)tetralin (8-OH-DPAT; 1-10 microM; n = 7). The data indicate that SFO neurons are responsive to serotonin via postsynaptic activation of multiple receptor subtypes. The results suggest that excitatory responses to serotonin are mediated by 5-HT2A or 5-HT2C receptors and that inhibitory responses may be mediated by 5-HT1A receptors. In addition, similar percentages of serotonin-excited and -inhibited cells were also sensitive to ANG II. As such the functional relationship between serotonin and ANG II in the SFO remains unclear.

  19. Different Serotonergic Expression in Nevomelanocytic Tumors

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    Naimi-Akbar, Clara; Ritter, Markus; Demel, Sasika; El-Nour, Husameldin; Hedblad, Mari-Anne [Dermatology and Venereology Unit, Department of Medicine, Solna, Karolinska Institutet, Karolinska University Hospital, Solna (Sweden); Azmitia, Efrain C. [Department of Biology and Psychiatry, New York University, NY (United States); Nordlind, Klas, E-mail: klas.nordlind@karolinska.se [Dermatology and Venereology Unit, Department of Medicine, Solna, Karolinska Institutet, Karolinska University Hospital, Solna (Sweden)

    2010-06-07

    The neuromediator serotonin (5-hydroxytryptamine; 5-HT) has been proposed to play a role in tumor progression. Thus, the aim of the present investigation was to determine whether alterations in the serotonergic system occur in nevomelanocytic tumors. For this purpose, paraffin-embedded biopsies of superficial spreading malignant melanoma (SSM), dysplastic compound nevi (DN) and benign compound nevi (BCN) were characterized with regard to their expression of 5-HT, the 5-HT1A and 5-HT2A receptors, and the serotonin transporter protein (SERT), by immunohistochemical analysis. Melanocytes in the region surrounding the tumor were found to express both the 5-HT1A and 5-HT2A receptors. Tumor cells that immunostained positively for the different serotonergic markers were observed in the suprabasal epidermis of DN tissue and, to an even greater extent, in the case of SSM. Furthermore, some of these latter cells expressed both 5-HT1AR and 5-HT2AR. The level of expression of 5-HT1AR at the junctional area was lower for SSM than for DN or BCN. As the degree of atypia increased, the intensity of tumor cell staining in the dermis for 5-HT1AR and SERT declined. Vessel immunoreactivity for 5-HT2A was more intense in SSM than in BCN tissue. Round-to-dendritic cells that expressed both SERT and 5-HT1AR were seen to infiltrate into the dermal region of the tumor, this infiltration being more evident in the case of DN and SSM. These latter cells were also tryptase-positive, indicating that they are mast cells. Thus, alterations in serotonergic system may be involved in nevomelanocytic tumors and mast cells may play an important role in this connection.

  20. Effects of white spirits on rat brain 5-HT receptor functions and synaptic remodeling.

    Science.gov (United States)

    Lam, H R; Plenge, P; Jørgensen, O S

    2001-01-01

    Previously, inhalation exposure to different types of white spirit (i.e. complex mixtures of aliphatic, aromatic, alkyl aromatic, and naphthenic hydrocarbons) has been shown to induce neurochemical effects in rat brains. Especially, the serotonergic system was involved at the global, regional, and subcellular levels. This study investigates the effects of two types of white spirit on 5-hydroxytryptamine (5-HT) transporters (5-HTT), 5-HT(2A) and 5-HT(4) receptor expression in forebrain, and on neural cell adhesion molecule (NCAM) and 25-kDa synaptosomal associated protein (SNAP-25) concentrations when applied as indices for synaptic remodeling in forebrain, hippocampus, and entorhinal cortex. Male Wistar rats were exposed to 0, 400, or 800 ppm of aromatic (20 vol.% aromatic hydrocarbons) or dearomatized white spirit (catalytically hydrogenated white spirit) in the inhaled air for 6 h/day, 7 days/week for 3 weeks. The 5-HTT B(max) and K(d) were not affected. Both types of white spirit at 800 ppm decreased B(max) for the 5-HT(2A) receptor. The aromatic type decreased the K(d) of the 5-HT(2A) and 5-HT(4) receptors at 800 ppm. Aromatic white spirit did not affect NCAM or SNAP-25 concentrations or NCAM/SNAP-25 ratio in forebrain, whereas NCAM increased in hippocampus and the NCAM/SNAP-25 ratio decreased in entorhinal cortex. Dearomatized white spirit did not affect NCAM, SNAP-25, or NCAM/SNAP-25 ratio in any brain region. The affected 5-HT receptor expression and synaptic plasticity marker proteins indicate that inhalation exposure to high concentrations of white spirit may be neurotoxic to rats, especially the aromatic white spirit type. PMID:11792528

  1. Neurobiological changes mediating the effects of chronic fluoxetine on cocaine use.

    Science.gov (United States)

    Sawyer, Eileen K; Mun, Jiyoung; Nye, Jonathon A; Kimmel, Heather L; Voll, Ronald J; Stehouwer, Jeffrey S; Rice, Kenner C; Goodman, Mark M; Howell, Leonard L

    2012-07-01

    Acute SSRI (selective serotonin reuptake inhibitor) treatment has been shown to attenuate the abuse-related effects of cocaine; however, SSRIs have had limited success in clinical trials for cocaine abuse, possibly due to neurobiological changes that occur during chronic administration. In order to better understand the role of serotonin (5HT) in cocaine abuse and treatment, we examined the effects of chronic treatment with the SSRI fluoxetine at clinically relevant serum concentrations on cocaine-related neurobiology and behavior. Rhesus macaques self-administering cocaine underwent a 6-week dosing regimen with fluoxetine designed to approximate serum concentrations observed in humans. Self-administration and reinstatement were monitored throughout the treatment and washout period. In vivo microdiaylsis was used to assess changes in dopaminergic and serotonergic neurochemistry. Positron emission tomography was used to assess changes in the 5HT transporter and 2A receptor binding potential (BP). Functional output of the 5HT system was assessed using prolactin levels. Cocaine-primed reinstatement and cocaine-elicited dopamine overflow were significantly suppressed following chronic fluoxetine treatment. 5HT2A receptor BP was increased in the frontal cortex following treatment while prolactin release was blunted, suggesting desensitization of the 5HT2A receptor. These effects persisted after a 6-week washout period. Measures of pre-synaptic serotonergic function and cocaine self-administration were unaffected. These data demonstrate that acute and chronic fluoxetine treatments exert different effects on cocaine-related behavior. Furthermore, chronic fluoxetine treatment causes alterations in 5HT2A receptors in the frontal cortex that may selectively disrupt cocaine-primed reinstatement. Fluoxetine may not be useful for treatment of ongoing cocaine abuse but may be useful in relapse prevention. PMID:22434223

  2. The role of 5-HT7 receptor antagonism in the amelioration of MK-801-induced learning and memory deficits by the novel atypical antipsychotic drug lurasidone.

    Science.gov (United States)

    Horisawa, Tomoko; Nishikawa, Hiroyuki; Toma, Satoko; Ikeda, Atsushi; Horiguchi, Masakuni; Ono, Michiko; Ishiyama, Takeo; Taiji, Mutsuo

    2013-05-01

    Lurasidone is a novel atypical antipsychotic with high affinity for dopamine D2, serotonin 5-HT7 and 5-HT2A receptors. We previously reported that lurasidone and the selective 5-HT7 receptor antagonist, SB-656104-A improved learning and memory deficits induced by MK-801, an N-methyl-d-aspartate (NMDA) receptor antagonist, in the rat passive avoidance test. In this study, we first examined the role of the 5-HT7 receptor antagonistic activity of lurasidone in its pro-cognitive effect to ameliorate MK-801-induced deficits in the rat passive avoidance test. The 5-HT7 receptor agonist, AS19, (2S)-(+)-5-(1,3,5-trimethylpyrazol-4-yl)-2-(dimethylamino) tetralin, (3 mg/kg, s.c.) completely blocked the attenuating effects of lurasidone (3 mg/kg, p.o.), highlighting the importance of 5-HT7 receptor antagonism in the pro-cognitive effect of lurasidone. AS19 (3 mg/kg, s.c.) also blocked the ameliorating effect of SB-656104-A (10 mg/kg, i.p.) in the same experimental paradigm. To further extend our observation, we next tested whether 5-HT7 receptor antagonism still led to the amelioration of MK-801-induced deficits when combined with D2 and 5-HT2A receptor antagonists, and found that SB-656104-A (10 mg/kg, i.p.) significantly ameliorated MK-801-induced deficits even in the presence of the D2 receptor antagonist raclopride (0.1 mg/kg, s.c.) and 5-HT2A receptor antagonist ketanserin (1 mg/kg, s.c.). Taken together, these results suggest that the 5-HT7 receptor antagonistic activity of lurasidone plays an important role in its effectiveness against MK-801-induced deficits, and may contribute to its pharmacological actions in patients with schizophrenia.

  3. Effects of psilocybin on hippocampal neurogenesis and extinction of trace fear conditioning.

    Science.gov (United States)

    Catlow, Briony J; Song, Shijie; Paredes, Daniel A; Kirstein, Cheryl L; Sanchez-Ramos, Juan

    2013-08-01

    Drugs that modulate serotonin (5-HT) synaptic concentrations impact neurogenesis and hippocampal (HPC)-dependent learning. The primary objective is to determine the extent to which psilocybin (PSOP) modulates neurogenesis and thereby affects acquisition and extinction of HPC-dependent trace fear conditioning. PSOP, the 5-HT2A agonist 25I-NBMeO and the 5-HT2A/C antagonist ketanserin were administered via an acute intraperitoneal injection to mice. Trace fear conditioning was measured as the amount of time spent immobile in the presence of the conditioned stimulus (CS, auditory tone), trace (silent interval) and post-trace interval over 10 trials. Extinction was determined by the number of trials required to resume mobility during CS, trace and post-trace when the shock was not delivered. Neurogenesis was determined by unbiased counts of cells in the dentate gyrus of the HPC birth-dated with BrdU co-expressing a neuronal marker. Mice treated with a range of doses of PSOP acquired a robust conditioned fear response. Mice injected with low doses of PSOP extinguished cued fear conditioning significantly more rapidly than high-dose PSOP or saline-treated mice. Injection of PSOP, 25I-NBMeO or ketanserin resulted in significant dose-dependent decreases in number of newborn neurons in hippocampus. At the low doses of PSOP that enhanced extinction, neurogenesis was not decreased, but rather tended toward an increase. Extinction of "fear conditioning" may be mediated by actions of the drugs at sites other than hippocampus such as the amygdala, which is known to mediate the perception of fear. Another caveat is that PSOP is not purely selective for 5-HT2A receptors. PSOP facilitates extinction of the classically conditioned fear response, and this, and similar agents, should be explored as potential treatments for post-traumatic stress disorder and related conditions.

  4. Serotonergic effects of dotarizine in coronary artery and in oocytes expressing 5-HT2 receptors.

    Science.gov (United States)

    Montiel, C; Herrero, C J; García-Palomero, E; Renart, J; García, A G; Lomax, R B

    1997-08-01

    In strips of pig coronary arteries incubated in oxygenated Krebs-bicarbonate solution at 37 degrees C, dotarizine blocked the phasic contractions evoked by 5-HT (0.5 microM) or K+ depolarization (35 mM K+) with an IC50 of 0.22 and 3.7 microM, respectively. Flunarizine inhibited both types of contractions with IC50 values of 1.7 microM for 5-HT and 2.4 microM for K+ responses. In Xenopus oocytes injected with in vitro transcribed RNA encoding for 5-HT2A or 5-HT2C receptors, 5-HT (100 nM for 20 s) applied every 10 min caused, in both cases, a reproducible inward current through Ca2(+)-activated Cl- channels (ICl). Dotarizine inhibited the 5-HT2A response in a concentration-dependent manner, with an IC50 of 2.2 nM. In contrast, the 5-HT2C response was unaffected by 1 microM dotarizine and blocked around 62% by 10 microM of this drug. The ICl activated either by intracellular injection of inositol 1,4,5-trisphosphate (IP3) in oocytes or by direct photorelease of Ca2+ in DM-nitrophen-injected oocytes was unaffected by 10 microM dotarizine. It is concluded that dotarizine blocks 5-HT2A receptors with a high affinity; the compound is devoid of intracellular effects on any further steps of the transduction pathway (i.e., IP3 receptor). Contrary to flunarizine that blocks equally well the serotonergic and the K+ vascular responses, dotarizine exhibits 17-fold higher affinity for vascular 5-HT receptors. These findings might be relevant to an understanding of the mechanism involved in the use of dotarizine and flunarizine as prophylactic agents in migraine.

  5. Serotonin 2A Receptors Differentially Contribute to Abuse-Related Effects of Cocaine and Cocaine-Induced Nigrostriatal and Mesolimbic Dopamine Overflow in Nonhuman Primates

    Science.gov (United States)

    Murnane, Kevin S.; Winschel, Jake; Schmidt, Karl T.; Stewart, LaShaya M.; Rose, Samuel J.; Cheng, Kejun; Rice, Kenner C.

    2013-01-01

    Two of the most commonly used procedures to study the abuse-related effects of drugs in laboratory animals are intravenous drug self-administration and reinstatement of extinguished behavior previously maintained by drug delivery. Intravenous self-administration is widely accepted to model ongoing drug-taking behavior, whereas reinstatement procedures are accepted to model relapse to drug taking following abstinence. Previous studies indicate that 5-HT2A receptor antagonists attenuate the reinstatement of cocaine-maintained behavior but not cocaine self-administration in rodents. Although the abuse-related effects of cocaine have been closely linked to brain dopamine systems, no previous study has determined whether this dissociation is related to differential regulation of dopamine neurotransmission. To elucidate the neuropharmacological and neuroanatomical mechanisms underlying this phenomenon, we evaluated the effects of the selective 5-HT2A receptor antagonist M100907 on intravenous cocaine self-administration and drug- and cue-primed reinstatement in rhesus macaques (Macaca mulatta). In separate subjects, we evaluated the role of 5-HT2A receptors in cocaine-induced dopamine overflow in the nucleus accumbens (n = 4) and the caudate nucleus (n = 5) using in vivo microdialysis. Consistent with previous studies, M100907 (0.3 mg/kg, i.m.) significantly attenuated drug- and cue-induced reinstatement but had no significant effects on cocaine self-administration across a range of maintenance doses. Importantly, M100907 (0.3 mg/kg, i.m.) attenuated cocaine-induced (1.0 mg/kg, i.v.) dopamine overflow in the caudate nucleus but not in the nucleus accumbens. These data suggest that important abuse-related effects of cocaine are mediated by distinct striatal dopamine projection pathways. PMID:23946394

  6. In Silico and In Vitro Analysis of Bacoside A Aglycones and Its Derivatives as the Constituents Responsible for the Cognitive Effects of Bacopa monnieri.

    Science.gov (United States)

    Ramasamy, Seetha; Chin, Sek Peng; Sukumaran, Sri Devi; Buckle, Michael James Christopher; Kiew, Lik Voon; Chung, Lip Yong

    2015-01-01

    Bacopa monnieri has been used in Ayurvedic medicine to improve memory and cognition. The active constituent responsible for its pharmacological effects is bacoside A, a mixture of dammarane-type triterpenoid saponins containing sugar chains linked to a steroid aglycone skeleton. Triterpenoid saponins have been reported to be transformed in vivo to metabolites that give better biological activity and pharmacokinetic characteristics. Thus, the activities of the parent compounds (bacosides), aglycones (jujubogenin and pseudojujubogenin) and their derivatives (ebelin lactone and bacogenin A1) were compared using a combination of in silico and in vitro screening methods. The compounds were docked into 5-HT1A, 5-HT2A, D1, D2, M1 receptors and acetylcholinesterase (AChE) using AutoDock and their central nervous system (CNS) drug-like properties were determined using Discovery Studio molecular properties and ADMET descriptors. The compounds were screened in vitro using radioligand receptor binding and AChE inhibition assays. In silico studies showed that the parent bacosides were not able to dock into the chosen CNS targets and had poor molecular properties as a CNS drug. In contrast, the aglycones and their derivatives showed better binding affinity and good CNS drug-like properties, were well absorbed through the intestines and had good blood brain barrier (BBB) penetration. Among the compounds tested in vitro, ebelin lactone showed binding affinity towards M1 (Ki = 0.45 μM) and 5-HT2A (4.21 μM) receptors. Bacoside A and bacopaside X (9.06 μM) showed binding affinity towards the D1 receptor. None of the compounds showed any inhibitory activity against AChE. Since the stimulation of M1 and 5-HT2A receptors has been implicated in memory and cognition and ebelin lactone was shown to have the strongest binding energy, highest BBB penetration and binding affinity towards M1 and 5-HT2A receptors, we suggest that B. monnieri constituents may be transformed in vivo to the

  7. In Silico and In Vitro Analysis of Bacoside A Aglycones and Its Derivatives as the Constituents Responsible for the Cognitive Effects of Bacopa monnieri.

    Directory of Open Access Journals (Sweden)

    Seetha Ramasamy

    Full Text Available Bacopa monnieri has been used in Ayurvedic medicine to improve memory and cognition. The active constituent responsible for its pharmacological effects is bacoside A, a mixture of dammarane-type triterpenoid saponins containing sugar chains linked to a steroid aglycone skeleton. Triterpenoid saponins have been reported to be transformed in vivo to metabolites that give better biological activity and pharmacokinetic characteristics. Thus, the activities of the parent compounds (bacosides, aglycones (jujubogenin and pseudojujubogenin and their derivatives (ebelin lactone and bacogenin A1 were compared using a combination of in silico and in vitro screening methods. The compounds were docked into 5-HT1A, 5-HT2A, D1, D2, M1 receptors and acetylcholinesterase (AChE using AutoDock and their central nervous system (CNS drug-like properties were determined using Discovery Studio molecular properties and ADMET descriptors. The compounds were screened in vitro using radioligand receptor binding and AChE inhibition assays. In silico studies showed that the parent bacosides were not able to dock into the chosen CNS targets and had poor molecular properties as a CNS drug. In contrast, the aglycones and their derivatives showed better binding affinity and good CNS drug-like properties, were well absorbed through the intestines and had good blood brain barrier (BBB penetration. Among the compounds tested in vitro, ebelin lactone showed binding affinity towards M1 (Ki = 0.45 μM and 5-HT2A (4.21 μM receptors. Bacoside A and bacopaside X (9.06 μM showed binding affinity towards the D1 receptor. None of the compounds showed any inhibitory activity against AChE. Since the stimulation of M1 and 5-HT2A receptors has been implicated in memory and cognition and ebelin lactone was shown to have the strongest binding energy, highest BBB penetration and binding affinity towards M1 and 5-HT2A receptors, we suggest that B. monnieri constituents may be transformed in vivo

  8. Two cases of mild serotonin toxicity via 5-hydroxytryptamine 1A receptor stimulation

    Directory of Open Access Journals (Sweden)

    Nakayama H

    2014-02-01

    Full Text Available Hiroto Nakayama,1,* Sumiyo Umeda,2,* Masashi Nibuya,3 Takeshi Terao,4 Koichi Nisijima,5 Soichiro Nomura3 1Yamaguchi Prefecture Mental Health Medical Center, Yamaguchi, Japan; 2Department of Psychiatry, NTT West Osaka Hospital, Osaka, Japan; 3Department of Psychiatry, National Defense Medical College, Saitama, Japan; 4Department of Neuropsychiatry, Oita University Faculty of Medicine, Oita, Japan; 5Department of Psychiatry, Jichi University School of Medicine, Tochigi, Japan  *These authors contributed equally to this work Abstract: We propose the possibility of 5-hydroxytryptamine (5-HT1A receptor involvement in mild serotonin toxicity. A 64-year-old woman who experienced hallucinations was treated with perospirone (8 mg/day. She also complained of depressed mood and was prescribed paroxetine (10 mg/day. She exhibited finger tremors, sweating, coarse shivering, hyperactive knee jerks, vomiting, diarrhea, tachycardia, and psychomotor agitation. After the discontinuation of paroxetine and perospirone, the symptoms disappeared. Another 81-year-old woman, who experienced delusions, was treated with perospirone (8 mg/day. Depressive symptoms appeared and paroxetine (10 mg/day was added. She exhibited tachycardia, finger tremors, anxiety, agitation, and hyperactive knee jerks. The symptoms disappeared after the cessation of paroxetine and perospirone. Recently, the effectiveness of coadministrating 5-HT1A agonistic psychotropics with selective serotonin reuptake inhibitors (SSRIs has been reported, and SSRIs with 5-HT1A agonistic activity have been newly approved in the treatment of depression. Perospirone is a serotonin–dopamine antagonist and agonistic on the 5-HT1A receptors. Animal studies have indicated that mild serotonin excess induces low body temperature through 5-HT1A, whereas severe serotonin excess induces high body temperature through 5-HT2A activation. Therefore, it could be hypothesized that mild serotonin excess induces side effects

  9. Return of the lysergamides. Part I: Analytical and behavioural characterization of 1-propionyl-d-lysergic acid diethylamide (1P-LSD).

    Science.gov (United States)

    Brandt, Simon D; Kavanagh, Pierce V; Westphal, Folker; Stratford, Alexander; Elliott, Simon P; Hoang, Khoa; Wallach, Jason; Halberstadt, Adam L

    2016-09-01

    1-Propionyl-d-lysergic acid diethylamide hemitartrate (1P-LSD) has become available as a 'research chemical' in the form of blotters and powdered material. This non-controlled derivative of d-lysergic acid diethylamide (LSD) has previously not been described in the published literature despite being closely related to 1-acetyl-LSD (ALD-52), which was developed in the 1950s. This study describes the characterization of 1P-LSD in comparison with LSD using various chromatographic and mass spectrometric methods, infrared and nuclear magnetic resonance spectroscopy. An important feature common to LSD and other serotonergic hallucinogens is that they produce 5-HT2A -receptor activation and induce the head-twitch response (HTR) in rats and mice. In order to assess whether 1P-LSD displays LSD-like properties and activates the 5-HT2A receptor, male C57BL/6 J mice were injected with vehicle (saline) or 1P-LSD (0.025-0.8 mg/kg, IP) and HTR assessed for 30 min using magnetometer coil recordings. It was found that 1P-LSD produced a dose-dependent increase in HTR counts, and that it had ~38% (ED50  = 349.6 nmol/kg) of the potency of LSD (ED50  = 132.8 nmol/kg). Furthermore, HTR was abolished when 1P-LSD administration followed pretreatment with the selective 5-HT2A receptor antagonist M100907 (0.1 mg/kg, SC), which was consistent with the concept that the behavioural response was mediated by activation of the 5-HT2A receptor. These results indicate that 1P-LSD produces LSD-like effects in mice, consistent with its classification as a serotonergic hallucinogen. Nevertheless, the extent to which 1P-LSD might show psychoactive effects in humans similar to LSD remains to be investigated. Copyright © 2015 John Wiley & Sons, Ltd.

  10. Total synthesis and evaluation of [18F]MHMZ

    DEFF Research Database (Denmark)

    Herth, Matthias M; Debus, Fabian; Piel, Markus;

    2008-01-01

    Radiochemical labeling of MDL 105725 using the secondary labeling precursor 2-[(18)F]fluoroethyltosylate ([(18)F]FETos) was carried out in yields of approximately 90% synthesizing [(18)F]MHMZ in a specific activity of approximately 50MBq/nmol with a starting activity of approximately 3GBq. Overall...... radiochemical yield including [(18)F]FETos synthon synthesis, [(18)F]fluoroalkylation and preparing the injectable [(18)F]MHMZ solution was 42% within a synthesis time of approximately 100 min. The novel compound showed excellent specific binding to the 5-HT(2A) receptor (K(i)=9.0 nM) in vitro and promising in...

  11. LEUPROLIDE INHIBITS MARBLE-BURYING BEHAVIOR VIA MODULATION OF 5-HT1B RECEPTOR

    OpenAIRE

    Parle Milind; Gaikwad Uday

    2011-01-01

    Obsessive compulsive disorder (OCD) is characterized by intrusive thoughts followed by repetitive behaviors. Serotonin-related genes found in OCD include those required for coding of 5-HT transporter and 5-HT receptors (5-HT2A, 5-HT2B, 5-HT2C and 5-HT1B). Marble-burying behavior of mice is a well-accepted paradigm to screen anti-compulsive activity. The aim of this study was to evaluate the effect of leuprolide alone and it’s combination with sumatriptan or ondansetron on marble-burying behav...

  12. High-Performance Liquid Chromatography with Tandem Mass Spectrometry for the Determination of Nine Hallucinogenic 25-NBOMe Designer Drugs in Urine Specimens

    OpenAIRE

    Poklis, Justin L.; Clay, Deborah J.; Poklis, Alphonse

    2014-01-01

    We present a high-performance liquid chromatography triple quadrupole mass spectrometry (HPLC–MS-MS) method for the identification and quantification of nine serotonin 5-HT2A receptor agonist hallucinogenic substances from a new class of N-methoxybenzyl derivatives of methoxyphenylethylamine (NBOMe) designer drugs in human urine: 25H-NBOMe, 2CC-NBOMe, 25I-NBF, 25D-NBOMe, 25B-NBOMe, 2CT-NBOMe, 25I-NBMD, 25G-NBOMe and 25I-NBOMe. This assay was developed for the Virginia Commonwealth University ...

  13. The time course of serotonin 2C receptor expression after spinal transection of rats

    DEFF Research Database (Denmark)

    Ren, Li-Qun; Wienecke, Jacob; Chen, Meng;

    2013-01-01

    In the spinal cord 5-HT systems modulate the spinal network via various 5-HT receptors. 5-HT2A and 2C receptors are likely the most important 5-HT receptors for enhancing the motoneuron excitability by facilitating the persistent inward current, and thus play an important role for the pathogenesis...... distributed in different regions of the spinal gray matter and was predominantly located in the neuronal somata and their dendrites although it seemed also present in axonal fibers in the superficial dorsal horn. 5-HT2CR-IR in different regions of the spinal gray matter was seen to be increased at 14 days...

  14. New halogenated tris-(phenylalkyl)amines as h5-HT2B receptor ligands.

    Science.gov (United States)

    Kapadia, Nirav; Ahmed, Shahrear; Harding, Wayne W

    2016-07-15

    A series of compounds in which various halogen substituents were incorporated into a phenyl ring of a tris-(phenylalkyl)amine scaffold, was synthesized and evaluated for affinity to h5-HT2 receptors. In general, all compounds were found to have good affinity for the 5-HT2B receptor and were selective over 5-HT2A and 5-HT2C receptors. Compound 9i was the most selective compound in this study and is the highest affinity 5-HT2B receptor ligand bearing a tris-(phenylalkyl)amine scaffold to date. PMID:27261181

  15. [Aggressive behavior: theoretical and biological aspects].

    Science.gov (United States)

    Giotakos, O

    2013-01-01

    that serotonin facilitates prefrontal inhibition and insufficient serotonergic activity may increase aggression levels. Gabaminergic activity reduce subcortical reactivity, and thus reduced gabaminergic activity may increase aggression. In addition, agonism of 5-HT2A receptor may increase impulsivity levels, while 5-HT2C receptor agonism may decrease it. An imbalance between these receptors with increased serotonergic activity at the 5-HT2A receptor and decreased 5-HT2C receptor sensitivity may increase the possibility of aggression. Fluoxetine may reserve this pattern by increasing presynaptic availability, decreasing 5-HT2A binding and enhancing signal at 5-HT2C receptors. Similarly, atypical antipsychotics, which in parallel with the D2 antagonism have a prominent 5-HT2A receptor antagonism, manifest significant antiaggressive properties. In addition mood stabilizers, affecting glutamatergic/gabaminergic balance, serve to the reduction of impulsive aggression, while lithium manifests positive effect on both suicidality and impulsive aggression. PMID:24200542

  16. The flavonoid quercetin reverses pulmonary hypertension in rats.

    Directory of Open Access Journals (Sweden)

    Daniel Morales-Cano

    Full Text Available Quercetin is a dietary flavonoid which exerts vasodilator, antiplatelet and antiproliferative effects and reduces blood pressure, oxidative status and end-organ damage in humans and animal models of systemic hypertension. We hypothesized that oral quercetin treatment might be protective in a rat model of pulmonary arterial hypertension. Three weeks after injection of monocrotaline, quercetin (10 mg/kg/d per os or vehicle was administered for 10 days to adult Wistar rats. Quercetin significantly reduced mortality. In surviving animals, quercetin decreased pulmonary arterial pressure, right ventricular hypertrophy and muscularization of small pulmonary arteries. Classic biomarkers of pulmonary arterial hypertension such as the downregulated expression of lung BMPR2, Kv1.5, Kv2.1, upregulated survivin, endothelial dysfunction and hyperresponsiveness to 5-HT were unaffected by quercetin. Quercetin significantly restored the decrease in Kv currents, the upregulation of 5-HT2A receptors and reduced the Akt and S6 phosphorylation. In vitro, quercetin induced pulmonary artery vasodilator effects, inhibited pulmonary artery smooth muscle cell proliferation and induced apoptosis. In conclusion, quercetin is partially protective in this rat model of PAH. It delayed mortality by lowering PAP, RVH and vascular remodeling. Quercetin exerted effective vasodilator effects in isolated PA, inhibited cell proliferation and induced apoptosis in PASMCs. These effects were associated with decreased 5-HT2A receptor expression and Akt and S6 phosphorylation and partially restored Kv currents. Therefore, quercetin could be useful in the treatment of PAH.

  17. Anxiolytic activity of the neuroprotective peptide HLDF-6 and its effects on brain neurotransmitter systems in BALB/c and C57BL/6 mice.

    Science.gov (United States)

    Zolotarev, Yurii A; Kovalev, Georgii I; Kost, Natalya V; Voevodina, Margarita E; Sokolov, Oleg Y; Dadayan, Alexander K; Kondrakhin, Evgenii A; Vasileva, Ekaterina V; Bogachuk, Anna P; Azev, Vyacheslav N; Lipkin, Valery M; Myasoedov, Nikolai F

    2016-09-01

    This study is focused on a new amide derivative of the peptide HLDF-6 (Thr-Gly-Glu-Asn-His-Arg). This hexapeptide is a fragment of Human Leukaemia Differentiation Factor (HLDF). It displays a broad range of nootropic and neuroprotective activities. We showed, for the first time, that the peptide HLDF-6-amide has high anxiolytic activity. We used 'open field' and 'elevated plus maze' tests to demonstrate anxiolytic effects of HLDF-6-amide (0.1 and 0.3 mg/kg intranasally), which were comparable to those of the reference drug diazepam (0.5 mg/kg). Five daily equipotent doses of HLDF-6-amide selectively mitigated anxiety and increased the density of NMDA receptors in the hippocampus of stress-susceptible BALB/c mice, and had no effect on stress-resilient C57BL/6 mice. The subchronic administration of HLDF-6-amide showed no effect on the density of GABAA and nicotine receptors but was accompanied by a nonselective decrease of the 5-HT2A serotonin receptor density in frontal cortex of both strains. The mechanism of the specific anxiolytic activity of HLDF-6-amide may include its action on the NMDA-glutamatergic receptor system of the hippocampus and on serotonin 5-HT2A-receptors in the prefrontal cortex. The psychotropic activity of HLDF-6-amide is promising for its introduction to medical practice as a highly effective anxiolytic medicine for mental and neurological diseases. PMID:27464742

  18. Using melanopsin to study G protein signaling in cortical neurons.

    Science.gov (United States)

    McGregor, K M; Bécamel, C; Marin, P; Andrade, R

    2016-09-01

    Our understanding of G protein-coupled receptors (GPCRs) in the central nervous system (CNS) has been hampered by the limited availability of tools allowing for the study of their signaling with precise temporal control. To overcome this, we tested the utility of the bistable mammalian opsin melanopsin to examine G protein signaling in CNS neurons. Specifically, we used biolistic (gene gun) approaches to transfect melanopsin into cortical pyramidal cells maintained in organotypic slice culture. Whole cell recordings from transfected neurons indicated that application of blue light effectively activated the transfected melanopsin to elicit the canonical biphasic modulation of membrane excitability previously associated with the activation of GPCRs coupling to Gαq-11 Remarkably, full mimicry of exogenous agonist concentration could be obtained with pulses as short as a few milliseconds, suggesting that their triggering required a single melanopsin activation-deactivation cycle. The resulting temporal control over melanopsin activation allowed us to compare the activation kinetics of different components of the electrophysiological response. We also replaced the intracellular loops of melanopsin with those of the 5-HT2A receptor to create a light-activated GPCR capable of interacting with the 5-HT2A receptor interacting proteins. The resulting chimera expressed weak activity but validated the potential usefulness of melanopsin as a tool for the study of G protein signaling in CNS neurons. PMID:27306679

  19. Dynamic alterations of serotonergic metabolism and receptors during social isolation of low- and high-active mice.

    Science.gov (United States)

    Rilke, O; Freier, D; Jähkel, M; Oehler, J

    1998-04-01

    Alterations induced by social isolation (1 day to 18 weeks) in low- and high-active mice (LAM and HAM) were studied in respect to serotonin metabolism, [3H]-8-OH-DPAT binding of presynaptic (midbrain), postsynaptic (hippocampus) 5-HT1A receptors and [3H]-ketanserin binding of cortical 5-HT2A receptors. Individual housing of mice was associated with reduction of serotonin metabolism, depending on isolation time and brain structure. Whereas a transient decrease in the striatum and cortex was detected between 1 week and 6 weeks, reduction of cerebellar and hippocampal serotonin metabolism was found later (12-18 weeks). Serotonergic systems of HAM were found to be more reactive to environmental disturbances, and their serotonin metabolism was more affected by social isolation. Isolation-induced upregulation of cortical 5-HT2A receptors was measured only in HAM. Densities of postsynaptic 5-HT1A receptors in the hippocampus did differ either in grouped or isolated mice. However, there were significant differences in hippocampal 5-HT1A receptor affinity, especially between 1 day and 3 weeks. Transient downregulation of presynaptic 5-HT1A receptors in the midbrain was found in isolated mice between 3 and 6 weeks. These results are discussed in terms of interactions between serotonergic alterations and isolation-induced aggression.

  20. 5-HT modulation of dopamine release in basal ganglia in psilocybin-induced psychosis in man--a PET study with [11C]raclopride.

    Science.gov (United States)

    Vollenweider, F X; Vontobel, P; Hell, D; Leenders, K L

    1999-05-01

    The modulating effects of serotonin on dopamine neurotransmission are not well understood, particularly in acute psychotic states. Positron emission tomography was used to examine the effect of psilocybin on the in vivo binding of [11C]raclopride to D2-dopamine receptors in the striatum in healthy volunteers after placebo and a psychotomimetic dose of psilocybin (n = 7). Psilocybin is a potent indoleamine hallucinogen and a mixed 5-HT2A and 5-HT1A receptor agonist. Psilocybin administration (0.25 mg/kg p.o.) produced changes in mood, disturbances in thinking, illusions, elementary and complex visual hallucinations and impaired ego-functioning. Psilocybin significantly decreased [11C]raclopride receptor binding potential (BP) bilaterally in the caudate nucleus (19%) and putamen (20%) consistent with an increase in endogenous dopamine. Changes in [11C]raclopride BP in the ventral striatum correlated with depersonalization associated with euphoria. Together with previous reports of 5-HT receptor involvement in striatal dopamine release, it is concluded that stimulation of both 5-HT2A and 5-HT1A receptors may be important for the modulation of striatal dopamine release in acute psychoses. The present results indirectly support the hypothesis of a serotonin-dopamine dysbalance in schizophrenia and suggest that psilocybin is a valuable tool in the analysis of serotonin-dopamine interactions in acute psychotic states.

  1. Psilocybin-induced stimulus control in the rat.

    Science.gov (United States)

    Winter, J C; Rice, K C; Amorosi, D J; Rabin, R A

    2007-10-01

    Although psilocybin has been trained in the rat as a discriminative stimulus, little is known of the pharmacological receptors essential for stimulus control. In the present investigation rats were trained with psilocybin and tests were then conducted employing a series of other hallucinogens and presumed antagonists. An intermediate degree of antagonism of psilocybin was observed following treatment with the 5-HT(2A) receptor antagonist, M100907. In contrast, no significant antagonism was observed following treatment with the 5-HT(1A/7) receptor antagonist, WAY-100635, or the DA D(2) antagonist, remoxipride. Psilocybin generalized fully to DOM, LSD, psilocin, and, in the presence of WAY-100635, DMT while partial generalization was seen to 2C-T-7 and mescaline. LSD and MDMA partially generalized to psilocybin and these effects were completely blocked by M-100907; no generalization of PCP to psilocybin was seen. The present data suggest that psilocybin induces a compound stimulus in which activity at the 5-HT(2A) receptor plays a prominent but incomplete role. In addition, psilocybin differs from closely related hallucinogens such as 5-MeO-DMT in that agonism at 5-HT(1A) receptors appears to play no role in psilocybin-induced stimulus control.

  2. Metabotropic glutamate receptor 2 and corticotrophin-releasing factor receptor-1 gene expression is differently regulated by BDNF in rat primary cortical neurons

    DEFF Research Database (Denmark)

    Jørgensen, Christinna V; Klein, Anders B; El-Sayed, Mona;

    2013-01-01

    Brain-derived neurotrophic factor (BDNF) is important for neuronal survival and plasticity. Incorporation of matured receptor proteins is an integral part of synapse formation. However, whether BDNF increases synthesis and integration of receptors in functional synapses directly is unclear. We...... are particularly interested in the regulation of the 5-hydroxytryptamine receptor 2A (5-HT2A R). This receptor form a functional complex with the metabotropic glutamate receptor 2 (mGluR2) and is recruited to the cell membrane by the corticotrophin-releasing factor receptor 1 (CRF-R1). The effect of BDNF on gene...... expression for all these receptors, as well as a number of immediate-early genes, was pharmacologically characterized in primary neurons from rat frontal cortex. BDNF increased CRF-R1 mRNA levels up to fivefold, whereas mGluR2 mRNA levels were proportionally downregulated. No effect on 5-HT2A R mRNA was seen...

  3. Association of the ADRA1A gene and the severity of metabolic abnormalities in patients with schizophrenia.

    Science.gov (United States)

    Cheng, Chin; Chiu, Hsien-Jane; Loh, El-Wui; Chan, Chin-Hong; Hwu, Tzong-Ming; Liu, Yun-Ru; Lan, Tsuo-Hung

    2012-01-10

    Patients with schizophrenia have a higher risk of developing metabolic abnormalities and their associated diseases. Some studies found that the accumulative number of metabolic syndrome components was associated with the severity of metabolic abnormalities. The purpose of this study was to examine the roles of the ADRA1A, ADRA2A, ADRB3, and 5HT2A genes in the risk of having more severe metabolic abnormalities among patients with schizophrenia. We studied a sample of 232 chronic inpatients with schizophrenia (120 males and 112 females) to explore the associations between the four candidate genes and the severity of metabolic syndrome by accumulative number of the components. Four single nucleotide polymorphisms in the candidate genes were genotyped, including the Arg347Cys in ADRA1A, the C1291G in ADRA2A, the Try64Arg in ADRB3, and the T102C in 5HT2A. An association between the accumulative number of metabolic syndrome components and the ADRA1A gene was found after adjusting age, sex, and other related variables (p-value=0.036). Presence of the Arg347 allele in the ADRA1A gene is a risk factor for having more severe metabolic abnormalities. These findings suggest a medical attention of closely monitoring metabolic risks for schizophrenia patients with high-risk genotypes. PMID:22037178

  4. Meta analysis on the relationship between 5-hydroxytryptamine 2A receptor gene polymorphism T102C and schizophrenia%中国人群5-HT2A受体基因T102C与精神分裂症患者关联性的Meta分析

    Institute of Scientific and Technical Information of China (English)

    黄月薪; 吴娴波; 吴晓翔

    2015-01-01

    目的 探讨5-羟色胺2A(5-hydroxytryptamine,5-HT2A)受体基因T102C多态性与精神分裂症患者相关性.方法 检索EMBASE、PubMed、CBM、CNKI、万方等数据库,收集在中国地区进行的与5-HT2A受体基因T102C多态性研究相关的文献,按照纳入与排除标准筛选整理相关数据后用Revman 5.0软件进行Meta分析,并进行文献发表偏倚检验.结果 检索到相关研究56篇,纳入符合标准的11篇文献,共收集4 728个研究个体,其中研究组例数2 135例,对照组人数2 593人.各研究均符合Hardy-Weinberg平衡(均P>0.05),Meta分析结果显示5-HT2A受体基因T102C多态性等位基因模型(Tvs C)、隐性基因模型(CC+CT) vs TT和共显性基因模型(TT vs CC和CT vs CC)三种基因模型差异无显著统计学意义(均P>0.05).显性基因模型(CT+TT) vs CC分析结果I2=45%有中度异质性,但采用亚组分析法去除Ni等的数据分析时I2=9%,Z=2.01,P<0.05.结论 5-HT2A受体基因T102C位点C等位基因为隐性基因,CC可能是治病因子,需待进一步循征研究提供证据.%Objective To assess the association of 5-hydroxytryptamine 2A (5-HT2A) receptor gene polymorphism with schizophrenia by Meta analysis.Methods Literatures on the relationship between 5-HT2A receptor gene polymorphism T102C and the Chinese schizophrenia in EMBASE,PubMed,CBM,CNKI and Wanfang Med Online were taken as research objects.Screening the relevant data according to the included and excluded standard,then,Software of RevMan 5.0 was employed to do Meta analysis.Meanwhile,we inspect the literatures publication bias.Results Twelve literatures were included,collecting 4 728 individuals,enrolling 2 135 for the schizophrenia group and 2 593 for the control group.The research conforms to Hardy Weinberg equilibrium (all P>0.05).The Meta analysis results showed that there was no significant association between 5-HT2A receptor gene polymorphism and schizophrenia including the allele model

  5. The antimalarial drug quinine interferes with serotonin biosynthesis and action.

    Science.gov (United States)

    Islahudin, Farida; Tindall, Sarah M; Mellor, Ian R; Swift, Karen; Christensen, Hans E M; Fone, Kevin C F; Pleass, Richard J; Ting, Kang-Nee; Avery, Simon V

    2014-01-01

    The major antimalarial drug quinine perturbs uptake of the essential amino acid tryptophan, and patients with low plasma tryptophan are predisposed to adverse quinine reactions; symptoms of which are similar to indications of tryptophan depletion. As tryptophan is a precursor of the neurotransmitter serotonin (5-HT), here we test the hypothesis that quinine disrupts serotonin function. Quinine inhibited serotonin-induced proliferation of yeast as well as human (SHSY5Y) cells. One possible cause of this effect is through inhibition of 5-HT receptor activation by quinine, as we observed here. Furthermore, cells exhibited marked decreases in serotonin production during incubation with quinine. By assaying activity and kinetics of the rate-limiting enzyme for serotonin biosynthesis, tryptophan hydroxylase (TPH2), we showed that quinine competitively inhibits TPH2 in the presence of the substrate tryptophan. The study shows that quinine disrupts both serotonin biosynthesis and function, giving important new insight to the action of quinine on mammalian cells.

  6. Gut microbes promote colonic serotonin production through an effect of short-chain fatty acids on enterochromaffin cells.

    Science.gov (United States)

    Reigstad, Christopher S; Salmonson, Charles E; Rainey, John F; Szurszewski, Joseph H; Linden, David R; Sonnenburg, Justin L; Farrugia, Gianrico; Kashyap, Purna C

    2015-04-01

    Gut microbiota alterations have been described in several diseases with altered gastrointestinal (GI) motility, and awareness is increasing regarding the role of the gut microbiome in modulating GI function. Serotonin [5-hydroxytryptamine (5-HT)] is a key regulator of GI motility and secretion. To determine the relationship among gut microbes, colonic contractility, and host serotonergic gene expression, we evaluated mice that were germ-free (GF) or humanized (HM; ex-GF colonized with human gut microbiota). 5-HT reduced contractile duration in both GF and HM colons. Microbiota from HM and conventionally raised (CR) mice significantly increased colonic mRNAs Tph1 [(tryptophan hydroxylase) 1, rate limiting for mucosal 5-HT synthesis; P cell numbers (cells producing 5-HT) were unchanged. Short-chain fatty acids (SCFAs) promoted TPH1 transcription in BON cells (human EC cell model). Thus, gut microbiota acting through SCFAs are important determinants of enteric 5-HT production and homeostasis. PMID:25550456

  7. Targeting brain serotonin synthesis: insights into neurodevelopmental disorders with long-term outcomes related to negative emotionality, aggression and antisocial behaviour

    OpenAIRE

    Lesch, Klaus-Peter; Araragi, Naozumi; Waider, Jonas; van den Hove, Daniel; Gutknecht, Lise

    2012-01-01

    Aggression, which comprises multi-faceted traits ranging from negative emotionality to antisocial behaviour, is influenced by an interaction of biological, psychological and social variables. Failure in social adjustment, aggressiveness and violence represent the most detrimental long-term outcome of neurodevelopmental disorders. With the exception of brain-specific tryptophan hydroxylase-2 (Tph2), which generates serotonin (5-HT) in raphe neurons, the contribution of gene variation to aggres...

  8. Time- and age-dependent effects of serotonin on gasping and autoresuscitation in neonatal mice.

    Science.gov (United States)

    Chen, Jianping; Magnusson, Jennifer; Karsenty, Gerard; Cummings, Kevin J

    2013-06-15

    The role of brain stem serotonin (5-hydroxytryptamine, 5-HT) in autoresuscitation in neonatal life is unclear. We hypothesized that a specific loss of 5-HT would compromise gasping and autoresuscitation mainly in the second postnatal week and that acute restoration of 5-HT would reverse the defects. We exposed postnatal day (P)4-5, P8-9, and P11-12 tryptophan-hydroxylase-2 knockout (TPH2(-/-)) and wild-type littermates (WT) to 10 episodes of anoxia (97% N2, 3% CO2), measuring survival, gasp latency, gasp frequency (fB), and the time required to restore eupnea and heart rate. We also tested P8-9 TPH2(-/-) mice after restoring 5-HT with a single injection of 5-hydroxytryptophan (5-HTP) 1-2 h before testing or with multiple injections beginning 24 h before testing. At P4-5 and P8-9, but not at P11-12, gasp latency and the recovery of eupnea were delayed ~2- to 3-fold in TPH2(-/-) pups compared with WT (P pups displayed reduced gasp fB (~20-30%; P rate recovery (~60%; P = 0.002) compared with WT littermates. TPH2(-/-) survival was reduced compared with WT (P pups, improved cardiorespiratory recovery and survival required 24 h of treatment. Our data suggest that 5-HT operates over a long time span (24 h) to improve survival during episodic severe hypoxia. Early in development (P4-9), 5-HT is critical for both respiratory and cardiovascular components of autoresuscitation; later (P11-12), it is critical mainly for cardiovascular components. Nevertheless, the effect of 5-HT deficiency on survival is most striking from P8 to P12. PMID:23558391

  9. Central anti-fatigue activity of verbascoside.

    Science.gov (United States)

    Zhu, Meiju; Zhu, Hongzhu; Tan, Ninghua; Wang, Hui; Chu, Hongbiao; Zhang, Chonglin

    2016-03-11

    In this study, the effects of verbascoside on treadmill exercise endurance, 5-hydroxytryptamine (5-HT) concentrations, the second isoforms of tryptophan hydroxylase (TPH2) and serotonergic type 1B inhibitory autoreceptors (5-HT1B) protein expression in the caudate putamen of exercised rats were investigated. Sixty Sprague-Dawley male rats were randomly divided into six groups: normal group, exercise group, exercise and verbascoside (0.1mg/kg)-treated group, exercise and verbascoside (1mg/kg)-treated group, exercise and verbascoside (10mg/kg)-treated group, exercise and caffeine (10mg/kg)-treated group. In exercise groups, rats were put on treadmill and forced to run for 30min once a day for 6 consecutive days. On the 7th day of the experiment, the time to exhaustion in treadmill exercise was determined for the trained groups. Immediately after the determination of the exhaustion time, all rats were sacrificed. 5-HT concentrations were detected by HPLC analysis. TPH2 and 5-HT1B protein expression were measured by western blot analysis. We found that verbascoside could prolong the time to exhaustion in treadmill exercise and suppress the exercise-induced increase of 5-HT synthesis and TPH2 protein expression, and prevent the exercise-induced decrease of 5-HT1B protein expression in the caudate putamen. Verbascoside was found as effective as caffeine in these effects. Verbascoside at 10mg/kg improved endurance of exercised rats. The mechanism of verbascoside' s anti-fatigue activity might be related to the inhibition of the exercise-induced synthesis of 5-HT and TPH2 expression, and to the increase of the 5-HT1B expression in the caudate putamen of exercised rats. PMID:26827721

  10. Genetic mapping of escalated aggression in wild-derived mouse strain MSM/Ms: association with serotonin-related genes

    Directory of Open Access Journals (Sweden)

    Aki eTakahashi

    2014-06-01

    Full Text Available The Japanese wild-derived mouse strain MSM/Ms (MSM retains a wide range of traits related to behavioral wildness, including high levels of emotionality and avoidance of humans. In this study, we observed that MSM showed a markedly higher level of aggression than the standard laboratory strain C57BL/6J. Whereas almost all MSM males showed high frequencies of attack bites and pursuit in the resident-intruder test, only a few C57BL/6J males showed aggressive behaviors, with these behaviors observed at only a low frequency. Sexually mature MSM males in their home cages killed their littermates, or sometimes female pair-mates. To study the genetic and neurobiological mechanisms that underlie the escalated aggression observed in MSM mice, we analyzed reciprocal F1 crosses and five consomic strains of MSM (Chr 4, 13, 15, X and Y against the background of C57BL/6J. We identified two chromosomes, Chr 4 and Chr 15, which were involved in the heightened aggression observed in MSM. These chromosomes had different effects on aggression: whereas MSM Chr 15 increased agitation and initiation of aggressive events, MSM Chr 4 induced a maladaptive level of aggressive behavior. Expression analysis of mRNAs of serotonin receptors, serotonin transporter and Tph2, an enzyme involved in serotonin synthesis in seven brain areas, indicated several differences among MSM, C57BL/6J, and their consomic strains. We found that Tph2 expression in the midbrain was increased in the Chr 4 consomic strain, as well as in MSM, and that there was a strong positive genetic correlation between aggressive behavior and Tph2 expression at the mRNA level. Therefore, it is possible that increased expression of the Tph2 gene is related to escalated aggression observed in MSM.

  11. Mice Genetically Depleted of Brain Serotonin do not Display a Depression-like Behavioral Phenotype

    OpenAIRE

    Angoa-Pérez, Mariana; Kane, Michael J.; Briggs, Denise I.; Herrera-Mundo, Nieves; Sykes, Catherine E.; Francescutti, Dina M.; Kuhn, Donald M

    2014-01-01

    Reductions in function within the serotonin (5HT) neuronal system have long been proposed as etiological factors in depression. Serotonin selective reuptake inhibitors (SSRIs) are the most common treatment for depression and their therapeutic effect is generally attributed to their ability to increase the synaptic levels of 5HT. Tryptophan hydroxylase 2 (TPH2) is the initial and rate-limiting enzyme in the biosynthetic pathway of 5HT in the CNS and losses in its catalytic activity lead to red...

  12. RFX transcription factor DAF-19 regulates 5-HT and innate immune responses to pathogenic bacteria in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Yusu Xie

    Full Text Available In Caenorhabditis elegans the Toll-interleukin receptor domain adaptor protein TIR-1 via a conserved mitogen-activated protein kinase (MAPK signaling cascade induces innate immunity and upregulates serotonin (5-HT biosynthesis gene tph-1 in a pair of ADF chemosensory neurons in response to infection. Here, we identify transcription factors downstream of the TIR-1 signaling pathway. We show that common transcription factors control the innate immunity and 5-HT biosynthesis. We demonstrate that a cysteine to tyrosine substitution in an ARM motif of the HEAT/Arm repeat region of the TIR-1 protein confers TIR-1 hyperactivation, leading to constitutive tph-1 upregulation in the ADF neurons, increased expression of intestinal antimicrobial genes, and enhanced resistance to killing by the human opportunistic pathogen Pseudomonas aeruginosa PA14. A forward genetic screen for suppressors of the hyperactive TIR-1 led to the identification of DAF-19, an ortholog of regulatory factor X (RFX transcription factors that are required for human adaptive immunity. We show that DAF-19 concerts with ATF-7, a member of the activating transcription factor (ATF/cAMP response element-binding B (CREB family of transcription factors, to regulate tph-1 and antimicrobial genes, reminiscent of RFX-CREB interaction in human immune cells. daf-19 mutants display heightened susceptibility to killing by PA14. Remarkably, whereas the TIR-1-MAPK-DAF-19/ATF-7 pathway in the intestinal immunity is regulated by DKF-2/protein kinase D, we found that the regulation of tph-1 expression is independent of DKF-2 but requires UNC-43/Ca(2+/calmodulin-dependent protein kinase (CaMK II. Our results suggest that pathogenic cues trigger a common core-signaling pathway via tissue-specific mechanisms and demonstrate a novel role for RFX factors in neuronal and innate immune responses to infection.

  13. The effects of child maltreatment on early signs of antisocial behavior: Genetic moderation by Tryptophan Hydroxylase, Serotonin Transporter, and Monoamine Oxidase-A-Genes

    OpenAIRE

    Cicchetti, Dante; Rogosch, Fred A.; Thibodeau, Eric

    2012-01-01

    Gene-environment interaction effects in predicting antisocial behavior in late childhood were investigated among maltreated and nonmaltreated low-income children (N = 627, M age = 11.27). Variants in three genes, TPH1, 5-HTTLPR, and MAOA uVNTR, were examined. In addition to child maltreatment status, we also considered the impact of maltreatment subtypes, developmental timing of maltreatment, and chronicity. Indicators of antisocial behavior were obtained from self-, peer-, and adult counselo...

  14. A link between serotonin-related gene polymorphisms, amygdala activity, and placebo-induced relief from social anxiety.

    Science.gov (United States)

    Furmark, Tomas; Appel, Lieuwe; Henningsson, Susanne; Ahs, Fredrik; Faria, Vanda; Linnman, Clas; Pissiota, Anna; Frans, Orjan; Bani, Massimo; Bettica, Paolo; Pich, Emilio Merlo; Jacobsson, Eva; Wahlstedt, Kurt; Oreland, Lars; Långström, Bengt; Eriksson, Elias; Fredrikson, Mats

    2008-12-01

    Placebo may yield beneficial effects that are indistinguishable from those of active medication, but the factors underlying proneness to respond to placebo are widely unknown. Here, we used functional neuroimaging to examine neural correlates of anxiety reduction resulting from sustained placebo treatment under randomized double-blind conditions, in patients with social anxiety disorder. Brain activity was assessed during a stressful public speaking task by means of positron emission tomography before and after an 8 week treatment period. Patients were genotyped with respect to the serotonin transporter-linked polymorphic region (5-HTTLPR) and the G-703T polymorphism in the tryptophan hydroxylase-2 (TPH2) gene promoter. Results showed that placebo response was accompanied by reduced stress-related activity in the amygdala, a brain region crucial for emotional processing. However, attenuated amygdala activity was demonstrable only in subjects who were homozygous for the long allele of the 5-HTTLPR or the G variant of the TPH2 G-703T polymorphism, and not in carriers of short or T alleles. Moreover, the TPH2 polymorphism was a significant predictor of clinical placebo response, homozygosity for the G allele being associated with greater improvement in anxiety symptoms. Path analysis supported that the genetic effect on symptomatic improvement with placebo is mediated by its effect on amygdala activity. Hence, our study shows, for the first time, evidence of a link between genetically controlled serotonergic modulation of amygdala activity and placebo-induced anxiety relief. PMID:19052197

  15. Extensive juvenile "babysitting" facilitates later adult maternal responsiveness, decreases anxiety, and increases dorsal raphe tryptophan hydroxylase-2 expression in female laboratory rats.

    Science.gov (United States)

    Harding, Kaitlyn M; Lonstein, Joseph S

    2016-05-01

    Pregnancy and parturition can dramatically affect female neurobiology and behavior. This is especially true for laboratory-reared rodents, in part, because such rearing prevents a host of developmental experiences that females might undergo in nature, including juvenile alloparenting. We examined the effect of chronic exposure to pups during post-weaning juvenile life (days 22-36) on adult maternal responsiveness, anxiety-related behaviors, and dorsal raphe tryptophan hydroxylase-2 (TPH2) and serotonin transporter (SERT) levels in nulliparous rats. Adult females with juvenile alloparental experience showed significantly faster sensitized maternal responsiveness, less anxiety, and more dorsal raphe TPH2. Juvenile alloparenting did not affect females' later social novelty and preference behaviors toward adults, suggesting their increased interest in pups did not extend to all social partners. In a second experiment, suckling a pregnant dam (achieved by postpartum estrus reinsemination), interacting with her after standard laboratory weaning age, and a 3-day exposure to younger siblings also reduced juvenile females' later anxiety but did not affect maternal responsiveness or TPH2. Thus, extensive juvenile "babysitting" can have long-term effects reminiscent of pregnancy and parturition on maternal responsiveness and anxiety, and these effects may be driven by upregulated serotonin. © 2016 Wiley Periodicals, Inc. Dev Psychobiol 58: 492-508, 2016. PMID:26806471

  16. Molecular Dynamics Simulation of Tryptophan Hydroxylase-1: Binding Modes and Free Energy Analysis to Phenylalanine Derivative Inhibitors

    Directory of Open Access Journals (Sweden)

    Liang Ouyang

    2013-05-01

    Full Text Available Serotonin is a neurotransmitter that modulates many central and peripheral functions. Tryptophan hydroxylase-1 (TPH1 is a key enzyme of serotonin synthesis. In the current study, the interaction mechanism of phenylalanine derivative TPH1 inhibitors was investigated using molecular dynamics (MD simulations, free energy calculations, free energy decomposition analysis and computational alanine scanning. The predicted binding free energies of these complexes are consistent with the experimental data. The analysis of the individual energy terms indicates that although the van der Waals and electrostatics interaction contributions are important in distinguishing the binding affinities of these inhibitors, the electrostatic contribution plays a more crucial role in that. Moreover, it is observed that different configurations of the naphthalene substituent could form different binding patterns with protein, yet lead to similar inhibitory potency. The combination of different molecular modeling techniques is an efficient way to interpret the interaction mechanism of inhibitors and our work could provide valuable information for the TPH1 inhibitor design in the future.

  17. A gene-expression-based neural code for food abundance that modulates lifespan.

    Science.gov (United States)

    Entchev, Eugeni V; Patel, Dhaval S; Zhan, Mei; Steele, Andrew J; Lu, Hang; Ch'ng, QueeLim

    2015-05-12

    How the nervous system internally represents environmental food availability is poorly understood. Here, we show that quantitative information about food abundance is encoded by combinatorial neuron-specific gene-expression of conserved TGFβ and serotonin pathway components in Caenorhabditis elegans. Crosstalk and auto-regulation between these pathways alters the shape, dynamic range, and population variance of the gene-expression responses of daf-7 (TGFβ) and tph-1 (tryptophan hydroxylase) to food availability. These intricate regulatory features provide distinct mechanisms for TGFβ and serotonin signaling to tune the accuracy of this multi-neuron code: daf-7 primarily regulates gene-expression variability, while tph-1 primarily regulates the dynamic range of gene-expression responses. This code is functional because daf-7 and tph-1 mutations bidirectionally attenuate food level-dependent changes in lifespan. Our results reveal a neural code for food abundance and demonstrate that gene expression serves as an additional layer of information processing in the nervous system to control long-term physiology.

  18. Genetic basis of unstable expression of high gamma-tocopherol content in sunflower seeds

    Directory of Open Access Journals (Sweden)

    García-Moreno María J

    2012-05-01

    Full Text Available Abstract Background Tocopherols are natural antioxidants with both in vivo (vitamin E and in vitro activity. Sunflower seeds contain predominantly alpha-tocopherol (>90% of total tocopherols, with maximum vitamin E effect but lower in vitro antioxidant action than other tocopherol forms such as gamma-tocopherol. Sunflower germplasm with stable high levels of gamma-tocopherol (>85% has been developed. The trait is controlled by recessive alleles at a single locus Tph2 underlying a gamma-tocopherol methyltransferase (gamma-TMT. Additionally, unstable expression of increased gamma-tocopherol content in the range from 5 to 85% has been reported. The objective of this research was to determine the genetic basis of unstable expression of high gamma-tocopherol content in sunflower seeds. Results Male sterile plants of nuclear male sterile line nmsT2100, with stable high gamma-tocopherol content, were crossed with plants of line IAST-1, with stable high gamma-tocopherol content but derived from a population that exhibited unstable expression of the trait. F2 seeds showed continuous segregation for gamma-tocopherol content from 1.0 to 99.7%. Gamma-tocopherol content in F2 plants (average of 24 individual F3 seeds segregated from 59.4 to 99.4%. A genetic linkage map comprising 17 linkage groups (LGs was constructed from this population using 109 SSR and 20 INDEL marker loci, including INDEL markers for tocopherol biosynthesis genes. QTL analysis revealed a major QTL on LG 8 that corresponded to the gamma-TMT Tph2 locus, which suggested that high gamma-tocopherol lines nmsT2100 and IAST-1 possess different alleles at this locus. Modifying genes were identified at LGs 1, 9, 14 and 16, corresponding in most cases with gamma-TMT duplicated loci. Conclusions Unstable expression of high gamma-tocopherol content is produced by the effect of modifying genes on tph2a allele at the gamma-TMT Tph2 gene. This allele is present in line IAST-1 and is different to

  19. Melatonin biosynthesizing enzyme genes and clock genes in ovary and whole brain of zebrafish (Danio rerio): Differential expression and a possible interplay.

    Science.gov (United States)

    Khan, Zeeshan Ahmad; Yumnamcha, Thangal; Rajiv, Chongtham; Devi, Haobijam Sanjita; Mondal, Gopinath; Devi, Sh Dharmajyoti; Bharali, Rupjyoti; Chattoraj, Asamanja

    2016-07-01

    The present study on zebrafish (Danio rerio) is the first attempt to demonstrate the circadian mRNA expression of melatonin biosynthesizing enzyme genes (Tph1a, Aanat1, Aanat2 and Hiomt) and clock associated genes (Bmal1a, Clock1a, Per1b, Per2 and Cry2a) in the ovary with a comparison to whole brain in normal (LD=12h L:12h D) and altered photic conditions (continuous dark, DD; continuous light, LL). Moreover, the present study also confirmed the ability of zebrafish ovary to biosynthesize melatonin both in vivo and in vitro with a significant difference at day and night. qRT-PCR analysis of genes revealed a dark acrophase of Aanat2 in both organs while Tph1 is in whole brain in LD condition. On the contrary, Bmal1a and Clock1a giving their peak in light, thereby showing a negative correlation with Tph1a and Aanat2. In LD-ovary, the acrophase of Tph1a, Bmal1a and Clock1a is in light and thus display a positive correlation. This trend of relationship in respect to Tph1a is not changing in altered photic conditions in both organs (except in DD-ovary). On the other hand this association for Aanat2 is varying in ovary under altered photic conditions but only in DD-whole brain. Both in LD and LL the expression of Aanat2 in brain presenting an opposite acrophase with both Bmal1a and Clock1a of ovary and consequently displaying a strong negative correlation among them. Interestingly, all ovarian clock associated genes become totally arrhythmic in DD, representing a loss of correlation between the melatonin synthesizing genes in brain and clock associated genes in ovary. The result is also indicating the formation of two heterodimers namely Clock1a:Bmal1a and Per2:Cry2a in the functioning of clock genes in both organs, irrespective of photic conditions, as they are exhibiting a strong significant positive correlation. Collectively, our data suggest that ovary of zebrafish is working as peripheral oscillator having its own melatonin biosynthesizing machinery and signifying a

  20. Antagonism of lateral saphenous vein serotonin receptors from steers grazing endophyte-free, wild-type, or novel endophyte-infected tall fescue.

    Science.gov (United States)

    Klotz, J L; Aiken, G E; Johnson, J M; Brown, K R; Bush, L P; Strickland, J R

    2013-09-01

    Pharmacologic profiling of serotonin (5HT) receptors of bovine lateral saphenous vein has shown that cattle grazing endophyte-infected (Neotyphodium coenophialum) tall fescue (Lolium arundinaceum) have altered responses to ergovaline, 5HT, 5HT2A, and 5HT7 agonists. To determine if 5HT receptor activity of tall fescue alkaloids is affected by grazing endophyte-free (EF), wild-type [Kentucky-31 (KY31)], novel endophyte AR542-infected (MAXQ), or novel endophyte AR584-infected (AR584) tall fescue, contractile responses of lateral saphenous veins biopsied from cattle grazing these different fescue-endophyte combinations were evaluated in presence or absence of antagonists for 5HT2A (ketanserin) or 5HT7 (SB-269970) receptors. Biopsies were conducted over 2 yr on 35 mixed-breed steers (361.5 ± 6.3 kg) grazing EF (n = 12), KY31 (n = 12), MAXQ (n = 6), or AR584 (n = 5) pasture treatments (3 ha) between 84 and 98 d (Yr 1) or 108 to 124 d (Yr 2). Segments (2 to 3 cm) of vein were surgically biopsied, sliced into 2- to 3-mm cross-sections, and suspended in a myograph chamber containing 5 mL of oxygenated Krebs-Henseleit buffer (95% O2/5% CO2; pH = 7.4; 37°C). Veins were exposed to increasing concentrations of 5HT, ergovaline, and ergovaline + 1 × 10(-5) M ketanserin or + 1 × 10(-6) M SB-269970 in Yr 1. In Yr 2, ergotamine and ergocornine were evaluated in presence or absence of 1 × 10(-5) M ketanserin. Contractile response data were normalized to a reference addition of 1 × 10(-4) M norepinephrine. In Yr 1, contractile response to 5HT and ergovaline were least (P ergotamine (P = 0.13) or ergocornine (P = 0.99) across pasture treatments, but ketanserin reduced (P < 0.05) the contractile response to both alkaloids. The 5HT2A receptor is involved in alkaloid-induced vascular contraction and alkaloid binding may be affected by exposure to different endophyte-fescue combinations. PMID:23825335

  1. Association of tryptophan hydroxylase-2 gene and family environment with antisocial personality disorder%色氨酸羟化酶2基因和家庭环境因素与反社会人格障碍的关联分析

    Institute of Scientific and Technical Information of China (English)

    吴岩峰; 潘风华; 谭钊安; 柯晓燕; 李云涛; 郑大同; 张建平; 茆正洪; 张建秋

    2011-01-01

    目的 探讨色氨酸羟化酶2(TPH2)基因、家庭环境因素及其交互作用与反社会人格障碍(ASPD)的关系.方法 选取TPH2基因rs4290270和rs7305115 2个多态性位点,采用聚合酶链反应-限制性片段长度多态性基因分型技术,测定117例反社会人格障碍患者(ASPD组)和142名健康人(对照组)的TPH2基因多态性分布,并运用家庭环境量表-中文版(Family Environment ScaleChinese Version,FES-CV)评估家庭环境.结果 ASPD组TPH2基因rs4290270、rs7305115 2个多态性位点的基因型和等位基因频率分布与对照组比较,差异均无统计学意义(P>0.05).ASPD组TA单体型频率显著高于对照组,差异有统计学意义(x2=6.177,P<0.05),相对危险度的估计值(OR)为1.865,95%可信区间(CI)为1.135~3.065;其他单体型在2组间的差异无统计学意义.家庭环境中的情感表达和道德宗教观2个因子与TA单体型存在交互作用(P<0.05),OR值分别为1.122和1.080,95%CI分别为1.043~1.206和1.010~1.155.结论 TPH2单体型TA可能与ASPD的发生有关,负性的家庭环境可能进一步加重携带危险单体型对个体的不利影响,个体发生反社会人格障碍的易感性更高.%objective To study the association of tryptophan hydroxylase 2(TPH2)gene polymorphism and family environment with antisocial personality disorder(ASPD)in Chinese Han population.Methods The single nucleotide polymorphism(SNPs)of TPH2,rs4290270 and rs7305115 were analyzed by PCR-RFLP genotyping assay in 117 ASPD patients and 142 healthy controls.The family Environment Scale-Chinese Version(FES-CV)was used to evaluate the family environment of all subjects.Results There were no significant differences between ASPD and controls in genotype and allele frequencies of rs4290270 and rs7305115.The distributions of TA haplotype was significantly more frequent in patients than in controls[odds ratio(OR)1.865,95%confidence interval(CI)1.135-3.065,P<0.05].Interactions between genetic and

  2. 抗精神病新药鲁拉西酮的药理与临床研究进展%Progress in pharmacological and clinical studies of antipsychotic drug:lurasidone

    Institute of Scientific and Technical Information of China (English)

    封宇飞

    2011-01-01

    Lurasidone is a novel psychotropic agent with high affinity for dopamine D2 and serotonin 5-HT2A receptors. Lurasidone has received accelerated approval from the FDA for the treatment of schizophrenia. A literature search was conducted using Medline with the key word lurasidone. Its pharmacology, pharmacokinetics and drug interactions, clinical study and safety were reviewed in this paper.%鲁拉西酮是一种新型抗精神病药,对多巴胺D和5-HT受体具有高度的亲和性.FDA批准其用于精神分裂症的治疗.文中通过Medline对鲁拉西酮进行文献检索,并对其药理作用、药动学、药物相互作用、临床研究和安全性进行了综述.

  3. [Serotonin and treatment of mental disorders. Present status and future perspectives].

    Science.gov (United States)

    Sevcík, J; Masek, K

    1997-07-14

    Serotoninergic system is involved in the regulation of diverse biological and psychological functions and a variety of serotonin receptor subtypes represent a possible target for a new generation of medications. 5-HT receptors play an important role in both schizophrenia and depression. Modern strategies for treating schizophrenia profit from the existence of interaction between serotonin and dopamine systems. New drugs called serotonin-dopamine antagonists (SDAs) offer wider spectra of activity and lower extrapyramidal side effects liability. The principle of the SDAs is that the drug should be a potent serotonin 5-HT 2A antagonist, with slightly less potent dopamine D2 receptor-blocking properties. New pharmacological agents with great therapeutic potential and fewer side effects were recently developed also for the treatment of depression. Among these new antidepressives the serotonin selective reuptake inhibitors (SSRIs) currently play the most important role. PMID:9340186

  4. Familial risk for mood disorder and the personality risk factor, neuroticism, interact in their association with frontolimbic serotonin 2A receptor binding

    DEFF Research Database (Denmark)

    Frøkjær, Vibe; Vinberg, Maj; Erritzøe, David;

    2010-01-01

    -twin history of mood disorder were included. They answered self-report personality questionnaires and underwent [(18)F]altanserin positron emission tomography. We found a significant interaction between neuroticism and familial risk in predicting the frontolimbic 5-HT(2A) receptor binding (p=0......Life stress is a robust risk factor for later development of mood disorders, particularly for individuals at familial risk. Likewise, scoring high on the personality trait neuroticism is associated with an increased risk for mood disorders. Neuroticism partly reflects stress vulnerability...... binding. These findings point at a plausible neurobiological link between genetic and personality risk factors and vulnerability to developing mood disorders. It contributes to our understanding of why some people at high risk develop mood disorders while others do not. We speculate that an increased...

  5. Evidence for the use of pimavanserin in the treatment of Parkinson’s disease psychosis

    Science.gov (United States)

    Sarva, Harini; Henchcliffe, Claire

    2016-01-01

    Parkinson’s disease (PD) is a progressive neurodegenerative disorder with both motor and nonmotor symptoms (NMS), leading to significant morbidity and caregiver burden. Psychosis is common but is under recognized by physicians. When present, it increases the patient’s risk of hospitalization and nursing home placement and caregiver burden. Although the atypical antipsychotic agent, clozapine, has been considered the gold standard treatment, severe agranulocytosis in 0.38% of patients and more commonly milder leukopenia, resulting in frequent blood testing, limit its use. Pimavanserin, a 5HT2A receptor inverse agonist, has been shown to reduce psychosis in PD without worsening motor symptoms. It is therefore a welcome therapeutic option for this devastating NMS. PMID:27800022

  6. Cluster analysis in kinetic modelling of the brain: A noninvasive alternative to arterial sampling

    DEFF Research Database (Denmark)

    Liptrot, Matthew George; Adams, K.H.; Martiny, L.;

    2004-01-01

    In emission tomography, quantification of brain tracer uptake, metabolism or binding requires knowledge of the cerebral input function. Traditionally, this is achieved with arterial blood sampling. We propose a noninvasive alternative via the use of a blood vessel time-activity curve (TAC......) extracted directly from dynamic positron emission tomography (PET) scans by cluster analysis. Five healthy subjects were injected with the 5HT2A- receptor ligand [18F]-altanserin and blood samples were subsequently taken from the radial artery and cubital vein. Eight regions-of-interest (ROI) TACs were...... by the 'within-variance' measure and by 3D visual inspection of the homogeneity of the determined clusters. The cluster-determined input curve was then used in Logan plot analysis and compared with the arterial and venous blood samples, and additionally with one of the currently used alternatives to arterial...

  7. 化合物XZ07抗精神分裂症活性及作用机制研究%Effects of compound XZ07 on schizophrenia models in mice and its mechanism

    Institute of Scientific and Technical Information of China (English)

    魏雅芹; 徐祥清

    2012-01-01

    Objective To investigate the effects of compound XZ07 on schizophrenia models in mice and its mechanism. Methods Using apomorphine - induced mice climbing model and MK - 801 - induced mice hyperlocomotion model to examine the effects of compound XZ07 on schizophrenia. The affinities of compound XZ07 on rat D2 and 5 - HT1A , 5 - HT2A receptors were evaluated in vitro binding assays using the radioligands [ 3H ] 8 - OH - DPAT , [ 3H ] -Ketanserin,[3 H ]-Spiperone,respectively. Results Compared with model group, compound XZ07 dose - dependently decreased the climbing scores in apomorphine -induced climbing test,meanwhile it also significantly inhibited the spontaneous activity ( P < 0.01 ) in MK - 801 - induced hyperlocomotion test at the dose of 10 and 30 mg/kg, but at low dose ( 3 mg/kg ) it had no affects on the spontaneous activity. At the in vitro binding test compound XZ07 showed high affinity on D2 and 5 - HT1A, 5 - HT2A receptors. Conclusion Compound XZ07 has effects on schizophrenia, its mechanism may be involved in 5 - HT1A , 5 - HT2A and D2 receptors.%目的 了解化合物XZ07抗精神分裂症活性,并对其作用机制进行初步探讨.方法 采用阿扑吗啡诱导小鼠攀爬模型及地卓西平(MK-801 )诱导小鼠高活动性模型,观察化合物XZ07对模型小鼠攀爬行为及活动总路程的影响来了解化合物XZ07抗精神分裂活性;大鼠断头取脑后提取脑内多巴胺(D2)、5-羟色胺1A(5-HT1A)及5-羟色胺2A(5-HT2A)受体蛋白,采用体外配体受体结合试验,通过观察化合物XZ07与D2、5-HT1A及5-HT2A受体的亲和性来初步了解其作用机制.结果 化合物XZ07高、中、低3个剂量都能剂量依赖性地抑制阿朴吗啡小鼠攀爬行为,显著减少小鼠攀爬试验中评分(P<0.01);化合物XZ07高、中剂量能显著减少MK-801诱导的高活动性小鼠90 min内总活动路程(P<0.01);体外受体试验发现,化合物XZ07与D2、5-HT1A及5-HT2A受体均具有较高的亲和力.结论

  8. Tesofensine, a novel triple monoamine reuptake inhibitor, induces appetite suppression by indirect stimulation of alpha1 adrenoceptor and dopamine D1 receptor pathways in the diet-induced obese rat

    DEFF Research Database (Denmark)

    Axel, Anne Marie Dixen; Mikkelsen, Jens D; Hansen, Henrik H

    2010-01-01

    Tesofensine is a novel monoamine reuptake inhibitor that inhibits both norepinephrine, 5-HT, and dopamine (DA) reuptake function. Tesofensine is currently in clinical development for the treatment of obesity, however, the pharmacological basis for its strong effect in obesity management...... is not clarified. Using a rat model of diet-induced obesity (DIO), we characterized the pharmacological mechanisms underlying the appetite suppressive effect of tesofensine. DIO rats treated with tesofensine (2.0 mg/kg, s.c.) for 16 days showed significantly lower body weights than vehicle-treated DIO rats, being...... antagonist), or ritanserin (0.03 mg/kg, 5-HT(2A/C) receptor antagonist). Hence, the mechanism underlying the suppression of feeding by tesofensine in the obese rat is dependent on the drug's ability to indirectly stimulate alpha(1) adrenoceptor and DA D(1) receptor function....

  9. Novel psychoactive substances: the pharmacology of stimulants and hallucinogens.

    Science.gov (United States)

    Schifano, Fabrizio; Papanti, G Duccio; Orsolini, Laura; Corkery, John M

    2016-07-01

    There are increasing levels of concern relating to the rapidly evolving novel psychoactive substances/NPS and web markets' scenarios. The paper aims at providing an overview of the clinical pharmacological issues related to some of the most popular NPS categories, e.g. stimulants and hallucinogens. NPS intake is typically associated with the imbalance of a complex range of neurotransmitter pathways/receptors, namely: dopamine; cannabinoid/CB1; and 5-HT2A. The intake is almost invariably undetectable with standard screening tests. Hence, it may frequently occur that the acute management of NPS misusers will need to focus on decreasing levels of both self/outward-directed aggression and agitation. Benzodiazepines may be considered as first line treatment. Alternatively, propofol and/or antipsychotics can be administered. Focus will be as well on treatment of possible rhabdomyolysis and hyperthermia. Indeed, future studies should inform better tailored management/treatment strategies. PMID:26985969

  10. Serotonergic involvement in stress-induced vasopressin and oxytocin secretion

    DEFF Research Database (Denmark)

    Jørgensen, Henrik; Knigge, Ulrich; Kjaer, Andreas;

    2002-01-01

    OBJECTIVE: To investigate the involvement of serotonin (5-hydroxytryptamine - 5-HT) receptors in mediation of stress-induced arginine vasopressin (AVP) and oxytocin (OT) secretion in male rats. DESIGN: Experiments on laboratory rats with control groups. METHODS: Different stress paradigms were...... applied after pretreatment with intracerebroventricular infusion of saline or different 5-HT antagonists. RESULTS: Restraint stress (5 min), hypotensive hemorrhage or dehydration for 24 h increased AVP secretion fivefold and OT secretion threefold. Swim stress for 3 min had no effect on AVP secretion......, but increased OT secretion threefold. Ether vapor or hypoglycemia had no effect on AVP or OT secretion. The restraint stress-induced AVP response was inhibited by pretreatment with the 5-HT(2A+2C) antagonists ketanserin (KET) and LY-53857 (LY) and the 5-HT(3+4) antagonist ICS-205930 (ICS), whereas the 5-HT(1A...

  11. Synthesis and pharmacological evaluation of several N-(2-nitrophenylpiperazine derivatives

    Directory of Open Access Journals (Sweden)

    DEANA ANDRIC

    2007-05-01

    Full Text Available Six newly synthesized heterocyclic (2-nitrophenylpiperazines, with a specific structure of the heteroaryl group, whichmimics the catechol moiety of dopamine (benzimidazoles and substituted benzimidazoles, were evaluated for their binding affinity to rat dopamine (DA, serotonin (5-HT and α1 receptors. All compounds with a benzimidazole group had a 5-HT2A/D2 receptors binding ratio characteristic for atypical neuroleptics (>1, pKi values. Compound 7c, 4-bromo-6-{2-[4-(2-nitrophenylpiperazin-1-yl]ethyl}-1H-benzimidazole, expressed higher affinities for all receptor classes than clozapine. Also, it exhibited the best characteristic for atypical neuroleptics and presents a compound with the best profile for further in vivo investigations.

  12. MR-based automatic delineation of volumes of interest in human brain PET images using probability maps

    DEFF Research Database (Denmark)

    Svarer, Claus; Madsen, Karina; Hasselbalch, Steen G.;

    2005-01-01

    delineation of the VOI set. The approach was also shown to work equally well in individuals with pronounced cerebral atrophy. Probability-map-based automatic delineation of VOIs is a fast, objective, reproducible, and safe way to assess regional brain values from PET or SPECT scans. In addition, the method......The purpose of this study was to develop and validate an observer-independent approach for automatic generation of volume-of-interest (VOI) brain templates to be used in emission tomography studies of the brain. The method utilizes a VOI probability map created on the basis of a database of several...... subjects' MR-images, where VOI sets have been defined manually. High-resolution structural MR-images and 5-HT(2A) receptor binding PET-images (in terms of (18)F-altanserin binding) from 10 healthy volunteers and 10 patients with mild cognitive impairment were included for the analysis. A template including...

  13. MR-based automatic delineation of volumes of interest in human brain PET images using probability maps

    DEFF Research Database (Denmark)

    Svarer, Claus; Madsen, Karina; Hasselbalch, Steen G.;

    2005-01-01

    delineation of the VOI set. The approach was also shown to work equally well in individuals with pronounced cerebral atrophy. Probability-map-based automatic delineation of VOIs is a fast, objective, reproducible, and safe way to assess regional brain values from PET or SPECT scans. In addition, the method...... applies well in elderly subjects, even in the presence of pronounced cerebral atrophy...... subjects' MR-images, where VOI sets have been defined manually. High-resolution structural MR-images and 5-HT(2A) receptor binding PET-images (in terms of (18)F-altanserin binding) from 10 healthy volunteers and 10 patients with mild cognitive impairment were included for the analysis. A template including...

  14. Lurasidone: The 2016 update on the pharmacology, efficacy and safety profile.

    Science.gov (United States)

    Jaeschke, Rafał R; Sowa-Kućma, Magdalena; Pańczyszyn-Trzewik, Patrycja; Misztak, Paulina; Styczeń, Krzysztof; Datka, Wojciech

    2016-08-01

    The aim of this paper was to review the up-to-date evidence base on pharmacology and clinical properties of lurasidone. Lurasidone is an atypical antipsychotic, approved by the US Food and Drug Administration (FDA) for the treatment of schizophrenia and bipolar depression. Lurasidone exhibits both an antipsychotic and antidepressant action. Based on its pharmacodynamics profile, it is believed that the drug's clinical action is mediated mainly through the D2, 5-HT2A and 5-HT7 receptors inhibition. In patients with schizophrenia the recommended dose range is 40-80mg/day. In bipolar depression broader dosage ranges (20-120mg/day) were found to be effective. In terms of side effects, higher rates of akathisia, parkinsonism and hyperprolactinemia were observed in individuals receiving lurasidone (as compared to patients treated with other atypical antipsychotics). On the other hand, treatment with lurasidone yields relatively lower risk for developing sedation or overweight/obesity. PMID:27203278

  15. Anxiolytic-like effects of DOI microinjections into the hippocampus (but not the amygdala nor the PAG) in the mice four plates test.

    Science.gov (United States)

    Masse, Fabienne; Petit-Demouliere, Benoit; Dubois, Isabelle; Hascoët, Martine; Bourin, Michel

    2008-04-01

    Anxiolytic-like effects of DOI, a 5-HT(2A/2C) agonist have been observed in the four plates test (FPT) after intra-peritoneal administrations. In the present study, DOI (1 microg, 2 microg or 5 microg per mice) was directly injected to three brain structures, the hippocampus, the amygdala and the periaqueductal gray matter (PAG). Tests were carried out immediately after injections. In amygdala and PAG, DOI exerted an anxiogenic-like effect. In the hippocampus, a strong anxiolytic-like effect was found only when injecting 5 microg DOI/mice in the FPT, with a size effect comparable to the anxiolytic-like effect of diazepam 1mg/kg injected intra-peritoneally. DOI or vehicle injections did not affect locomotor activity. These results help us to understand mechanisms of action of DOI in animal models of anxiety, probably through an interaction with other neurotransmitter system, which may take place in the hippocampus.

  16. 5-Hydroxytryptamine (serotonin 2A receptor gene polymorphism is associated with schizophrenia

    Directory of Open Access Journals (Sweden)

    Subash Padmajeya Sujitha

    2014-01-01

    Full Text Available Background & objectives: Schizophrenia, the debilitating neuropsychiatric disorder, is known to be heritable, involving complex genetic mechanisms. Several chromosomal regions associated with schizophrenia have been identified during the past; putative gene (s in question, to be called the global signature for the pathophysiology of the disease, however, seems to evade us. The results obtained from the several population-wise association-non association studies have been diverse. w0 e therefore, undertook the present study on Tamil speaking population in south India to examine the association between the single nucleotide polymorphisms (SNPs at the serotonin receptor gene (5HT2A and the occurrence of the disease. Methods: Blood samples collected from 266 cases and 272 controls were subjected to genotyping (PCR amplification of candidate SNPs, RFLP and sequencing. The data on the SNPs were subjected to statistical analysis for assessing the gene frequencies in both the cases and the controls. Results: The study revealed significant association between the genotypic frequencies of the serotonin receptor polymorphism and schizophrenia. SNP analysis revealed that the frequencies of GG (30%, rs6311 and CC genotypes (32%, rs6313, were higher in patients (P<0.05 than in controls. The study also showed presence of G and C alleles in patients. s0 ignificant levels of linkage disequilibrium (LD were found to exist between the genotype frequencies of rs6311 and rs6313. Interpretation & conclusions: This study indicated an association between the SNPs (rs6311 and rs6313 of the serotonin receptor 5HT2A and schizophrenia. HapMap analysis revealed that in its genotype distribution, the Tamil speaking population was different from several other populations across the world, signifying the importance of such ethnicity-based studies to improve our understanding of this complex disease.

  17. Serotonin1A receptors in the pathophysiology of schizophrenia: development of novel cognition-enhancing therapeutics.

    Science.gov (United States)

    Sumiyoshi, Tomiki; Bubenikova-Valesova, Vera; Horacek, Jiri; Bert, Bettina

    2008-10-01

    Serotonin (5-HT) receptors have been suggested to play key roles in psychosis, cognition, and mood via influence on neurotransmitters, synaptic integrity, and neural plasticity. Specifically, genetic evidence indicates that 5-HT(1A), 5-HT(2A), and 5-HT(2C) receptor single-nucleotide polymorphisms (SNPs) are related to psychotic symptoms, cognitive disturbances, and treatment response in schizophrenia. Data from animal research suggest the role of 5-HT in cognition via its influence on dopaminergic, cholinergic, glutamatergic, and GABAergic function. This article provides up-to-date findings on the role of 5-HT receptors in endophenotypic variations in schizophrenia and the development of newer cognition-enhancing medications, based on basic science and clinical evidence. Imaging genetics studies on associations of polymorphisms of several 5-HT receptor subtypes with brain structure, function, and metabolism suggest a role for the prefrontal cortex and the parahippocampal gyrus in cognitive impairments of schizophrenia. Data from animal experiments to determine the effect of agonists/antagonists at 5-HT(1A), 5-HT(2A), and 5-HT(2C) receptors on behavioral performance in animal models of schizophrenia based on the glutamatergic hypothesis provide useful information. For this purpose, standard as well as novel cognitive tasks provide a measure of memory/information processing and social interaction. In order to scrutinize mixed evidence for the ability of 5-HT(1A) agonists/antagonists to improve cognition, behavioral data in various paradigms from transgenic mice overexpressing 5-HT(1A) receptors provide valuable insights. Clinical trials reporting the advantage of 5-HT(1A) partial agonists add to efforts to shape pharmacologic perspectives concerning cognitive enhancement in schizophrenia by developing novel compounds acting on 5-HT receptors. Overall, these lines of evidence from translational research will facilitate the development of newer pharmacologic strategies

  18. 5-HT2 receptor blocker sarpogrelate prevents downregulation of antiapoptotic protein Bcl-2 and protects the heart against ischemia-reperfusion injury.

    Science.gov (United States)

    Rajesh, Katare Gopalrao; Suzuki, Ryoko; Maeda, Hironori; Murio, Yamamoto; Sasaguri, Shiro

    2006-09-27

    Even though reperfusion is the treatment of choice in patients admitted with acute myocardial infarction, reperfusion itself has been demonstrated to activate various pathological factors especially following procedures of cardiac revascularization. 5-hydroxytryptamine (5HT) is one such factor activated during reperfusion and is known to trigger the post ischemic contractile dysfunction and pathological apoptosis. Here we demonstrate the potential effects of the 5-HT(2)A antagonist sarpogrelate in protecting the myocardium against reperfusion injury of heart. Male Wistar rats weighing between 220 and 240 g were subjected to 30 min left coronary artery (LCA) occlusion and 120 min reperfusion. Sarpogrelate (4 mg/kg) was infused intravenously for 30 min either before LCA occlusion or at reperfusion. Following reperfusion the samples were collected for infarction area, immunohistochemistry, western blotting and myocardial metabolite analysis. Sarpogrelate infusion before ischemia resulted in (a) significant recovery of post ischemic cardiac functions (LVDP, EDP), (b) significant reduction in the infarct size among the risk area after triphenyl tetrazolium chloride staining (p<0.001), (c) decreased tissue water content (p<0.05), (d) well preserved myocardial ATP (p<0.05), (e) reduction in Bcl-2 downregulation and caspase 3 activation and (g) less prevalence of apoptotic cells (3.1+/-0.4% to 15.2+/-0.6%, drug versus control). Treating the rats with sarpogrelate during reperfusion also showed similar results. This study thus demonstrates the protective effects of sarpogrelate and supports the role for 5-HT2A inhibition in preventing the reperfusion injury of the heart. PMID:16876202

  19. Predicting targets of compounds against neurological diseases using cheminformatic methodology.

    Science.gov (United States)

    Nikolic, Katarina; Mavridis, Lazaros; Bautista-Aguilera, Oscar M; Marco-Contelles, José; Stark, Holger; do Carmo Carreiras, Maria; Rossi, Ilaria; Massarelli, Paola; Agbaba, Danica; Ramsay, Rona R; Mitchell, John B O

    2015-02-01

    Recently developed multi-targeted ligands are novel drug candidates able to interact with monoamine oxidase A and B; acetylcholinesterase and butyrylcholinesterase; or with histamine N-methyltransferase and histamine H3-receptor (H3R). These proteins are drug targets in the treatment of depression, Alzheimer's disease, obsessive disorders, and Parkinson's disease. A probabilistic method, the Parzen-Rosenblatt window approach, was used to build a "predictor" model using data collected from the ChEMBL database. The model can be used to predict both the primary pharmaceutical target and off-targets of a compound based on its structure. Molecular structures were represented based on the circular fingerprint methodology. The same approach was used to build a "predictor" model from the DrugBank dataset to determine the main pharmacological groups of the compound. The study of off-target interactions is now recognised as crucial to the understanding of both drug action and toxicology. Primary pharmaceutical targets and off-targets for the novel multi-target ligands were examined by use of the developed cheminformatic method. Several multi-target ligands were selected for further study, as compounds with possible additional beneficial pharmacological activities. The cheminformatic targets identifications were in agreement with four 3D-QSAR (H3R/D1R/D2R/5-HT2aR) models and by in vitro assays for serotonin 5-HT1a and 5-HT2a receptor binding of the most promising ligand (71/MBA-VEG8).

  20. Serotonin increases synaptic activity in olfactory bulb glomeruli.

    Science.gov (United States)

    Brill, Julia; Shao, Zuoyi; Puche, Adam C; Wachowiak, Matt; Shipley, Michael T

    2016-03-01

    Serotoninergic fibers densely innervate olfactory bulb glomeruli, the first sites of synaptic integration in the olfactory system. Acting through 5HT2A receptors, serotonin (5HT) directly excites external tufted cells (ETCs), key excitatory glomerular neurons, and depolarizes some mitral cells (MCs), the olfactory bulb's main output neurons. We further investigated 5HT action on MCs and determined its effects on the two major classes of glomerular interneurons: GABAergic/dopaminergic short axon cells (SACs) and GABAergic periglomerular cells (PGCs). In SACs, 5HT evoked a depolarizing current mediated by 5HT2C receptors but did not significantly impact spike rate. 5HT had no measurable direct effect in PGCs. Serotonin increased spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs) in PGCs and SACs. Increased sEPSCs were mediated by 5HT2A receptors, suggesting that they are primarily due to enhanced excitatory drive from ETCs. Increased sIPSCs resulted from elevated excitatory drive onto GABAergic interneurons and augmented GABA release from SACs. Serotonin-mediated GABA release from SACs was action potential independent and significantly increased miniature IPSC frequency in glomerular neurons. When focally applied to a glomerulus, 5HT increased MC spontaneous firing greater than twofold but did not increase olfactory nerve-evoked responses. Taken together, 5HT modulates glomerular network activity in several ways: 1) it increases ETC-mediated feed-forward excitation onto MCs, SACs, and PGCs; 2) it increases inhibition of glomerular interneurons; 3) it directly triggers action potential-independent GABA release from SACs; and 4) these network actions increase spontaneous MC firing without enhancing responses to suprathreshold sensory input. This may enhance MC sensitivity while maintaining dynamic range. PMID:26655822

  1. Lateral/Basolateral Amygdala Serotonin Type-2 Receptors Modulate Operant Self-administration of a Sweetened Ethanol Solution via Inhibition of Principal Neuron Activity

    Directory of Open Access Journals (Sweden)

    Brian eMccool

    2014-01-01

    Full Text Available The lateral/basolateral amygdala (BLA forms an integral part of the neural circuitry controlling innate anxiety and learned fear. More recently, BLA dependent modulation of self-administration behaviors suggests a much broader role in the regulation of reward evaluation. To test this, we employed a self-administration paradigm that procedurally segregates ‘seeking’ (exemplified as lever-press behaviors from consumption (drinking directed at a sweetened ethanol solution. Microinjection of the nonselective serotonin type-2 receptor agonist, alpha-methyl-5-hydroxytryptamine (-m5HT into the BLA reduced lever pressing behaviors in a dose-dependent fashion. This was associated with a significant reduction in the number of response-bouts expressed during non-reinforced sessions without altering the size of a bout or the rate of responding. Conversely, intra-BLA -m5HT only modestly effected consumption-related behaviors; the highest dose reduced the total time spent consuming a sweetened ethanol solution but did not inhibit the total number of licks, number of lick bouts, or amount of solution consumed during a session. In vitro neurophysiological characterization of BLA synaptic responses showed that -m5HT significantly reduced extracellular field potentials. This was blocked by the 5-HT2A/C antagonist ketanserin suggesting that 5-HT2-like receptors mediate the behavioral effect of -m5HT. During whole-cell patch current-clamp recordings, we subsequently found that -m5HT increased action potential threshold and hyperpolarized the resting membrane potential of BLA pyramidal neurons. Together, our findings show that the activation of BLA 5-HT2A/C receptors inhibits behaviors related to reward-seeking by suppressing BLA principal neuron activity. These data are consistent with the hypothesis that the BLA modulates reward-related behaviors and provides specific insight into BLA contributions during operant self-administration of a

  2. Inhibitory Effect of Serotonin Antagonist on Leukocyte-Endothelial Interactions In Vivo and In Vitro.

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    Hiroshi Kataoka

    Full Text Available Although 5-HT2A serotonergic antagonists have been used to treat vascular disease in patients with diabetes mellitus or obesity, their effects on leukocyte-endothelial interactions have not been fully investigated. In this study, we assessed the effects of sarpogrelate hydrochloride (SRPO, a 5-HT2A receptor inverse agonist, on leukocyte-endothelial cell interactions in obesity both in vivo and in vitro.In the in vivo experiment, C57BL/6 mice were fed a high-fat high-fructose diet (HFFD, comprising 20% fat and 30% fructose, with or without intraperitoneal injection of 5 mg/kg/day SRPO for 4 weeks. The body weight, visceral fat weight, and serum monocyte chemoattractant protein-1 levels in the mice increased significantly with the HFFD, but these effects were prevented by chronic injections of SRPO. Intravital microscopy of the femoral artery detected significant leukocyte-endothelial interactions after treatment with HFFD, but these leukocyte-endothelial interactions were reduced in the mice injected with SRPO. In the in vitro experiment, pre-incubation of activated human umbilical vein endothelial cells (HUVECs with platelet-rich plasma (PRP induced THP-1 cell adhesion under physiological flow conditions, but the adhesion was reduced by pretreatment of PRP with SRPO. A fluorescent immunobinding assay showed that PRP induced significant upregulation of E-selectin in HUVECs, but this upregulation was reduced by pretreatment of PRP with SRPO. In other in vitro conditions, pre-incubation of THP-1 cells with phorbol 12-myristate 13-acetate increased the adhesion of THP-1 cells to activated HUVECs under rotational conditions, but this adhesion was reduced by pretreatment with SRPO. Western blotting analysis showed that protein kinase C α activation in THP-1 cells was inhibited by SRPO.Our findings indicated that SRPO inhibits vascular inflammation in obesity via inactivation of platelets and leukocytes, and improvement of obese.

  3. M-100907 (Aventis).

    Science.gov (United States)

    de Paulis, T

    2001-01-01

    M-100907 is a highly selective 5-HT2A antagonist that is being developed by Aventis Pharmaceuticals, formerly Hoechst Marion Roussel (HMR), for the potential treatment of schizophrenia. M-100907 is in phase III trials for chronic schizophrenia [307936], [307942], [307940]. In August 1999, development was discontinued for acute schizophrenia (schizoaffective disorder) on the basis of poor results [335083]. M-100907 is a potent antagonist in every putative animal behavioral model of schizophrenia that involves activation of 5-HT2A receptors [181713]. Interestingly, M-100907 is also active in animal models involving blockade of NMDA glutamatergic channel receptors, an effect known to resemble some behavioral symptoms of schizophrenia in man [390328]. M-100907 belongs to a series of piperidine derivatives, which were originally disclosed in the associated patent, EP-00208235. M-100907 is specifically claimed in a later patent, EP-00531410. This patent describes superior in vivo potency for M-100907 and its claims include the use of M-100907 for the treatment of thromboembolic disorders. The use of M-100907 for the treatment of various developmental neurological disorders such as autism and attention deficit hyperactivity disorder is disclosed in WO-09956750. In 1996, this product was designated one of HMR's nine top priority products, serving an unmet medical need and addressing a potential market in excess of US $500 million per year [221118]. In January 1999, BT Alex Brown predicted sales of US $30 million in 2000 rising to US $220 million in 2002 [318220]. In April 1999, ABN Amro predicted annual sales of DM 50 million in 2000, rising to DM 150 million in 2002 [328676].

  4. Influence of serotonergic/noradrenergic gene polymorphisms on nausea and sweating induced by milnacipran in the treatment of depression

    Directory of Open Access Journals (Sweden)

    Hisashi Higuchi, Hitoshi Takahashi

    2009-07-01

    Full Text Available Hisashi Higuchi1, Hitoshi Takahashi2, Mitsuhiro Kamata3, Keizo Yoshida41Department of Psychiatry, St. Marianna University, School of Medicine, Kanagawa, Japan; 2Department of Psychiatry, Tokyo Women’s Medical University, School of Medicine, Tokyo, Japan; 3Department of Psychiatry, Yuri-Kumiai General Hospital, Yuri-Honjo, Akita, Japan; 4Department of Psychiatry, Nagoya University School of Medicine, Aichi, JapanAbstract: The present study was conducted to find out the predictors of side effects such as nausea and excessive sweating induced by milnacipran, a serotonin/norepinephrine reuptake inhibitor. Both clinical characteristics prior to the treatment and gene polymorphisms such as serotonin transporter (5-HTT gene-linked polymorphic region (5-HTTLPR, a variable number of tandem repeats in the second intron of the 5-HTT gene (5-HTTVNTR, 5-HT2A receptor gene (5-HT2A G-1438A, a TPH gene polymorphism in intron 7 (TPH A218C, norepinephrine transporter (NET gene polymorphism in the promoter region (NET T-182C and in the exon 9 (NET G1287A, a variable number of tandem repeats in the promoter region of monoamine oxidase A, were items to be assessed in this study. Ninety-six patients with major depressive disorder were treated with milnacipran. Side effects were assessed at 1, 2, 4, and 6 weeks of treatment with Udvalg for Kliniske Undersogelser side effects scale. The results showed that no gene polymorphisms included in this study affected the susceptibility of nausea and excessive sweating induced by milnacipran. Patients with older age are more likely to develop excessive sweating than others. The major limitation of this study is a small sample size. Further studies with larger populations and more kinds of gene polymorphisms should be needed to see if specific gene polymorphisms determine the susceptibility of side effects induced by milnacipran. Keywords: milnacipran, nausea, excessive sweating, gene polymorphisms

  5. The effect of the sigma-1 receptor selective compound LS-1-137 on the DOI-induced head twitch response in mice.

    Science.gov (United States)

    Malik, Maninder; Rangel-Barajas, Claudia; Mach, Robert H; Luedtke, Robert R

    2016-09-01

    Several receptor mediated pathways have been shown to modulate the murine head twitch response (HTR). However, the role of sigma receptors in the murine (±)-2,5-dimethoxy-4-iodoamphetamine (DOI)-induced HTR has not been previously investigated. We examined the ability of LS-1-137, a novel sigma-1 vs. sigma-2 receptor selective phenylacetamide, to modulate the DOI-induced HTR in DBA/2J mice. We also assessed the in vivo efficacy of reference sigma-1 receptor antagonists and agonists PRE-084 and PPCC. The effect of the sigma-2 receptor selective antagonist RHM-1-86 was also examined. Rotarod analysis was performed to monitor motor coordination after LS-1-137 administration. Radioligand binding techniques were used to determine the affinity of LS-1-137 at 5-HT2A and 5-HT2C receptors. LS-1-137 and the sigma-1 receptor antagonists haloperidol and BD 1047 were able to attenuate a DOI-induced HTR, indicating that LS-1-137 was acting in vivo as a sigma-1 receptor antagonist. LS-1-137 did not compromise rotarod performance within a dose range capable of attenuating the effects of DOI. Radioligand binding studies indicate that LS-1-137 exhibits low affinity binding at both 5-HT2A and 5-HT2C receptors. Based upon the results from these and our previous studies, LS-1-137 is a neuroprotective agent that attenuates the murine DOI-induced HTR independent of activity at 5-HT2 receptor subtypes, D2-like dopamine receptors, sigma-2 receptors and NMDA receptors. LS-1-137 appears to act as a sigma-1 receptor antagonist to inhibit the DOI-induced HTR. Therefore, the DOI-induced HTR can be used to assess the in vivo efficacy of sigma-1 receptor selective compounds.

  6. Serotonin receptors are involved in the spinal mediation of descending facilitation of surgical incision-induced increase of Fos-like immunoreactivity in rats

    Directory of Open Access Journals (Sweden)

    Prado Wiliam A

    2010-03-01

    Full Text Available Abstract Background Descending pronociceptive pathways may be implicated in states of persistent pain. Paw skin incision is a well-established postoperative pain model that causes behavioral nociceptive responses and enhanced excitability of spinal dorsal horn neurons. The number of spinal c-Fos positive neurons of rats treated intrathecally with serotonin, noradrenaline or acetylcholine antagonists where evaluated to study the descending pathways activated by a surgical paw incision. Results The number of c-Fos positive neurons in laminae I/II ipsilateral, lamina V bilateral to the incised paw, and in lamina X significantly increased after the incision. These changes: remained unchanged in phenoxybenzamine-treated rats; were increased in the contralateral lamina V of atropine-treated rats; were inhibited in the ipsilateral lamina I/II by 5-HT1/2B/2C (methysergide, 5-HT2A (ketanserin or 5-HT1/2A/2C/5/6/7 (methiothepin receptors antagonists, in the ipsilateral lamina V by methysergide or methiothepin, in the contralateral lamina V by all the serotonergic antagonists and in the lamina X by LY 278,584, ketanserin or methiothepin. Conclusions We conclude: (1 muscarinic cholinergic mechanisms reduce incision-induced response of spinal neurons inputs from the contralateral paw; (2 5-HT1/2A/2C/3 receptors-mediate mechanisms increase the activity of descending pathways that facilitates the response of spinal neurons to noxious inputs from the contralateral paw; (3 5-HT1/2A/2C and 5-HT1/2C receptors increases the descending facilitation mechanisms induced by incision in the ipsilateral paw; (4 5-HT2A/3 receptors contribute to descending pronociceptive pathways conveyed by lamina X spinal neurons; (5 α-adrenergic receptors are unlikely to participate in the incision-induced facilitation of the spinal neurons.

  7. Effects of sarpogrelate hydrochloride on skin ulcers and quality of life in patients with systemic sclerosis.

    Science.gov (United States)

    Yoshimasu, Takashi; Ikeda, Takaharu; Uede, Koji; Kanazawa, Nobuo; Furukawa, Fukumi

    2012-06-01

    5-Hydroxytryptamine 2A serotonin receptor (5-HT(2A) ) is associated with the contraction of vascular smooth muscle, platelet aggregation and thrombus formation and coronary artery spasms. Sarpogrelate hydrochloride (sarpogrelate) is a selective 5-HT(2A) antagonist and was supposed to be effective for Raynaud's phenomenon with collagen disease. Sarpogrelate has not been investigated regarding the effects, safety and quality of life (QOL) in patient with skin ulcers of collagen disease. Eleven patients with skin ulcers and systemic sclerosis (SSc) were administrated sarpogrelate p.o. three times a day for 3-6 months. The area (mean ± standard error) of skin ulcer at the pretreatment, and after 3 and 6 months of sarpogrelate intake was 2.1 ± 0.8, 0.2 ± 0.1 and 0.1 ± 0.1 mm(2), respectively. The reduction of skin ulcer area was significant after 3 months of sarpogrelate intake. In assessment of QOL, scores of symptoms and emotions but not of functioning were significantly improved after sarpogrelate intake. The global score (mean ± SE) of Skindex-16 at pretreatment, and after 3 and 6 months of sarpogrelate intake was 31.8 ± 8.7, 23.7 ± 8.3 and 10.9 ± 4.6, respectively. The score was significantly improved after 6 months of sarpogrelate intake. There were no obvious side-effects during this study. Sarpogrelate was considered to be a useful drug to improve skin ulcers and QOL in patients with SSc. PMID:22077618

  8. Risperidone induces long-lasting changes in the conditioned avoidance response and accumbal gene expression selectively in animals treated as adolescents.

    Science.gov (United States)

    Moe, Aung Aung Kywe; Kurniawan, Nyoman D; Alexander, Suzanne; Cui, Xiaoying; Burne, Thomas H J; Eyles, Darryl W

    2016-09-01

    Adolescence is a period of dynamic remodeling and maturation in the brain. Exposure to psychotropic drugs during adolescence can potentially alter neural maturation in the adolescent brain subsequently altering neural function at maturity. In this regard, antipsychotic drugs (APDs) are important given a notable global increase in prescription of these APDs to adolescents for a variety of behavioural symptoms and conditions over the past twenty years. However, there is a paucity of data on the long-term consequences of APDs on the adolescent brain. In this preclinical study, we have examined whether the adolescent brain is more susceptible than the adult brain to long-term neural changes induced by risperidone, which is the APD most frequently prescribed to adolescents. Rats were chronically treated (21 days) with 1.3 mg/kg/day risperidone or vehicle either as adolescents (postnatal day (PND) 36-56)) or adults (PND80-100). Behaviour was assessed using the well-described suppression of the conditioned avoidance response (CAR) by APDs. We examined CAR after all animals had reached maturity (PND127). We show that mature rats treated with risperidone as adolescents had increased CAR suppression compared to adults when rechallenged with this same drug. In the nucleus accumbens, significant downregulation of serotonergic 5HT2A receptors and catechol-o-methyl transferase mRNA levels was observed only in the adolescent treated animals. Impaired 5HT2A receptor signaling may explain the increased CAR suppression observed in rats treated with risperidone as adolescents. Magnetic resonance imaging (MRI), however, did not detect any risperidone-induced long-term brain structural change at maturity. These findings confirm that APD administration during adolescence may produce long-term behavioural and neurochemical alterations. PMID:27130903

  9. The effect of psilocin on memory acquisition, retrieval and consolidation in rat.

    Directory of Open Access Journals (Sweden)

    Lukas eRambousek

    2014-05-01

    Full Text Available The involvement of the serotonin system in the pathophysiology of schizophrenia has been elucidated by experiments with hallucinogens. Application of a hallucinogen to humans leads to changes in perception, cognition, emotions and induction of psychotic-like symptoms that resemble symptoms of schizophrenia. In rodent studies, their acute administration affects sensorimotor gating, locomotor activity, social behavior and cognition including working memory, the phenotypes are considered as an animal model of schizophrenia. The complexity and singularity of human cognition raises questions about the validity of animal models utilizing agonists of 5-HT2A receptors. The present study thus investigated the effect of psilocin on memory acquisition, reinforced retrieval and memory consolidation in rats. Psilocin is a main metabolite of psilocybin acting as an agonist at 5-HT2A receptors with a contribution of 5-HT2C and 5-HT1A receptors. First, we tested the effect of psilocin on the acquisition of a Carousel maze, a spatial task requiring navigation using distal cues, attention and cognitive coordination. Psilocin significantly impaired the acquisition of the Carousel Maze at both doses (1 and 4 mg/kg. The higher dose of psilocin blocked the learning processes even in an additional session when the rats received only saline. Next, we examined the effect of psilocin on reinforced retrieval and consolidation in the Morris water maze (MWM. The dose of 4 mg/kg disrupted reinforced retrieval in the Morris water maze. However, the application of a lower dose was without any significant effect. Finally, neither the low nor high dose of psilocin injected post-training caused a deficit in memory consolidation in the MWM. Taken together, the psilocin dose dependently impaired the acquisition of the Carousel maze and reinforced retrieval in MWM; however, it had no effect on memory consolidation.

  10. Effects of psilocybin on time perception and temporal control of behaviour in humans.

    Science.gov (United States)

    Wittmann, Marc; Carter, Olivia; Hasler, Felix; Cahn, B Rael; Grimberg, Ulrike; Spring, Philipp; Hell, Daniel; Flohr, Hans; Vollenweider, Franz X

    2007-01-01

    Hallucinogenic psilocybin is known to alter the subjective experience of time. However, there is no study that systematically investigated objective measures of time perception under psilocybin. Therefore, we studied dose-dependent effects of the serotonin (5-HT)2A/1A receptor agonist psilocybin (4-phosphoryloxy-N, N-dimethyltryptamine) on temporal processing, employing tasks of temporal reproduction, sensorimotor synchronization and tapping tempo. To control for cognitive and subjective changes, we assessed spatial working memory and conscious experience. Twelve healthy human volunteers were tested under placebo, medium (115 microg/kg), and high (250 microg/kg) dose conditions, in a double-blind experimental design. Psilocybin was found to significantly impair subjects' ability to (1) reproduce interval durations longer than 2.5 sec, (2) to synchronize to inter-beat intervals longer than 2 sec and (3) caused subjects to be slower in their preferred tapping rate. These objective effects on timing performance were accompanied by working-memory deficits and subjective changes in conscious state, namely increased reports of 'depersonalization' and 'derealization' phenomena including disturbances in subjective 'time sense.' Our study is the first to systematically assess the impact of psilocybin on timing performance on standardized measures of temporal processing. Results indicate that the serotonin system is selectively involved in duration processing of intervals longer than 2 to 3 seconds and in the voluntary control of the speed of movement. We speculate that psilocybin's selective disruption of longer intervals is likely to be a product of interactions with cognitive dimensions of temporal processing -presumably via 5-HT2A receptor stimulation.

  11. Gene expression changes in the prefrontal cortex, anterior cingulate cortex and nucleus accumbens of mood disorders subjects that committed suicide.

    Directory of Open Access Journals (Sweden)

    Adolfo Sequeira

    Full Text Available Suicidal behaviors are frequent in mood disorders patients but only a subset of them ever complete suicide. Understanding predisposing factors for suicidal behaviors in high risk populations is of major importance for the prevention and treatment of suicidal behaviors. The objective of this project was to investigate gene expression changes associated with suicide in brains of mood disorder patients by microarrays (Affymetrix HG-U133 Plus2.0 in the dorsolateral prefrontal cortex (DLPFC: 6 Non-suicides, 15 suicides, the anterior cingulate cortex (ACC: 6NS, 9S and the nucleus accumbens (NAcc: 8NS, 13S. ANCOVA was used to control for age, gender, pH and RNA degradation, with P ≤ 0.01 and fold change ± 1.25 as criteria for significance. Pathway analysis revealed serotonergic signaling alterations in the DLPFC and glucocorticoid signaling alterations in the ACC and NAcc. The gene with the lowest p-value in the DLPFC was the 5-HT2A gene, previously associated both with suicide and mood disorders. In the ACC 6 metallothionein genes were down-regulated in suicide (MT1E, MT1F, MT1G, MT1H, MT1X, MT2A and three were down-regulated in the NAcc (MT1F, MT1G, MT1H. Differential expression of selected genes was confirmed by qPCR, we confirmed the 5-HT2A alterations and the global down-regulation of members of the metallothionein subfamilies MT 1 and 2 in suicide completers. MTs 1 and 2 are neuro-protective following stress and glucocorticoid stimulations, suggesting that in suicide victims neuroprotective response to stress and cortisol may be diminished. Our results thus suggest that suicide-specific expression changes in mood disorders involve both glucocorticoids regulated metallothioneins and serotonergic signaling in different regions of the brain.

  12. Activity of sap from Croton lechleri on rat vascular and gastric smooth muscles.

    Science.gov (United States)

    Froldi, G; Zagotto, G; Filippini, R; Montopoli, M; Dorigo, P; Caparrotta, L

    2009-08-01

    The effects of red sap from Croton lechleri (SdD), Euphorbiaceae, on vascular and gastric smooth muscles were investigated. SdD, from 10 to 1000 microg/ml, induced concentration-dependent vasoconstriction in rat caudal arteries, which was endothelium-independent. In arterial preparations pre-constricted by phenylephrine (0.1 microM) or KCl (30 mM), SdD also produced concentration-dependent vasoconstriction. To study the mechanisms implicated in this effect we used selective inhibitors such as prazosin (0.1 microM), an antagonist of alpha(1)-adrenoceptors, atropine (0.1 microM), an antagonist of muscarinic receptors, and ritanserin (50 nM), a 5-HT(2A) antagonist; none of these influenced vasoconstriction caused by SdD. Likewise, nifedipine (50 nM), an inhibitor of L-type calcium channels, did not modify the action of SdD. Capsaicin (100 nM), an agonist of vanilloid receptors, also did not affect vasoconstriction by SdD. We also investigated the action of SdD (10-1000 microg/ml) on rat gastric fundus; per se the sap slightly increased contractile tension. When the gastric fundus was pre-treated with SdD (100 microg/ml) the contraction induced by carbachol (1 microM) was increased, whereas that by KCl (60mM) or capsaicin (100 nM) were unchanged. The data shows that SdD increased contractile tension in a concentration-dependent way, both on vascular and gastric smooth muscles. The vasoconstriction is unrelated to alpha(1), M, 5-HT(2A) and vanilloid receptors as well as L-type calcium channels. SdD increased also contraction by carbachol on rat gastric fundus. Thus for the first time, experimental data provides evidence that sap from C. lechleri owns constricting activity on smooth muscles. PMID:19406630

  13. In Vitro and In Vivo Characterization of the Alkaloid Nuciferine.

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    Martilias S Farrell

    Full Text Available The sacred lotus (Nelumbo nucifera contains many phytochemicals and has a history of human use. To determine which compounds may be responsible for reported psychotropic effects, we used in silico predictions of the identified phytochemicals. Nuciferine, an alkaloid component of Nelumbo nucifera and Nymphaea caerulea, had a predicted molecular profile similar to antipsychotic compounds. Our study characterizes nuciferine using in vitro and in vivo pharmacological assays.Nuciferine was first characterized in silico using the similarity ensemble approach, and was followed by further characterization and validation using the Psychoactive Drug Screening Program of the National Institute of Mental Health. Nuciferine was then tested in vivo in the head-twitch response, pre-pulse inhibition, hyperlocomotor activity, and drug discrimination paradigms.Nuciferine shares a receptor profile similar to aripiprazole-like antipsychotic drugs. Nuciferine was an antagonist at 5-HT2A, 5-HT2C, and 5-HT2B, an inverse agonist at 5-HT7, a partial agonist at D2, D5 and 5-HT6, an agonist at 5-HT1A and D4 receptors, and inhibited the dopamine transporter. In rodent models relevant to antipsychotic drug action, nuciferine blocked head-twitch responses and discriminative stimulus effects of a 5-HT2A agonist, substituted for clozapine discriminative stimulus, enhanced amphetamine induced locomotor activity, inhibited phencyclidine (PCP-induced locomotor activity, and rescued PCP-induced disruption of prepulse inhibition without induction of catalepsy.The molecular profile of nuciferine was similar but not identical to that shared with several approved antipsychotic drugs suggesting that nuciferine has atypical antipsychotic-like actions.

  14. Effects of 5-hydroxytryptamine and 5-hydroxytryptamine 2A/2C agonist on the genioglossus activity and sleep apnea in rats

    Institute of Scientific and Technical Information of China (English)

    ZHONG Yi-jue; ZHANG Cheng; WANG Guang-fa

    2010-01-01

    Background 5-hydroxytryptamine (5-HT) is a common neurotransmitter in the brain which plays an important role in the pathogenesis of sleep apnea.Dysfunction of 5-HT and 5-HT2 receptors may lead to the collapse of the upper airway and the instability of respiratory control, which in turn produce apnea.Genioglossus (GG) is one of the most important oropharyngeal muscles maintaining the upper airway open.The present study aimed to investigate the effects of 5-HT and 5-HT2 receptor on GG activity and the sleep apnea in Sprague-Dawley (SD) rats.Methods Microinjection probes were placed within the fourth ventricle of sixteen SD rats.After recovery for a week, the electromyogram (EMG) of GG was recorded in the anesthetized and vagotomized rats.The changes of GG activity before and after the microinjection of 5-HT or 5-HT2A/2c agonist -2,5-dimethoxy-4-iodoamphetamine hydrochloride (DOI)were observed.Probes were also laid in another eight SD rats.Electroencephalogram (EEG), EMG of neck muscle and respiration were recorded at the same time a week later.The effects of DOI on the occurrence of sleep apnea were explored.Results Both 5-HT and DOI significantly enhanced the activity of GG just 3 minutes after the completion of injection.The effect of 5-HT disappeared quickly and the effect of DOI lasted for more than 27 minutes.DOI also significantly decreased the post-sigh apnea index in non-rapid-eye-movement (NREM) and rapid-eye-movement (REM) sleep and decreased the spontaneous apnea index only in NREM sleep (P <0.05, respectively).Conclusion 5-HT and 5-HT2A/2c system correlated closely with the pathogenesis of the sleep apnea syndrome and 5-HT receptors may become the target of the drug treatment.

  15. Effects of Supplement of Tryptophan on Behavior and Related Hormones in Piglets After Mixing%饲粮中添加色氨酸对仔猪混群后行为及相关激素的影响

    Institute of Scientific and Technical Information of China (English)

    刘化伟; 石宝明; 娄蕾; 王红

    2012-01-01

    [目的]研究饲粮中添加色氨酸对仔猪混群后行为、相关激素水平和5-羟色胺受体2A(5-HT2A)基因表达的影响.[方法]将144头体重相近(8.00±0.25) kg的28日龄断奶仔猪随机分为3个处理组,即对照组、处理组Ⅰ和Ⅱ;每组设6个重复,每个重复有8头猪.对照组饲喂色氨酸含量为0.21%的基础饲粮,处理组Ⅰ和Ⅱ分别在基础饲粮的基础上添加0.1%和0.2%的色氨酸,饲喂28 d后混群,观察猪的争斗行为和日常行为,测定唾液皮质醇浓度、下丘脑5-羟色胺含量和5-HT2A基因表达量.[结果]混群后,与对照组相比,添加色氨酸的处理组仔猪争斗时间和争斗次数显著降低(P<0.05),趴卧行为显著提高(P<0.05),站立行为显著降低(P< 0.05),采食、犬坐行为无显著差异(P>0.05);随饲粮色氨酸水平的提高,仔猪唾液皮质醇含量显著降低(P<0.05),下丘脑中5-羟色胺浓度显著升高(P<0.05),下丘脑中5-HT2A mRNA相对表达量依次降低,其中添加0.2%的色氨酸组与对照组相比差异显著(P<0.05).[结论]在满足仔猪色氨酸营养需要(0.21%)的基础上,额外添加0.1%和0.2%的色氨酸能提高仔猪下丘脑5-羟色胺的含量,调控5-HT2A基因mRNA的表达水平,降低仔猪混群后唾液皮质醇的含量,进而缓解仔猪混群后的应激行为.%[Objective] The objectives of this experiment were to evaluate the effects of dietary tryptophan on behavior, concentrations of relative hormones and expression of 5-HT2A mRNA in piglets after mixing. [Method] A total of 144 weaning piglets at 28 d of age with initial average weight at (8.00.25) kg were assigned to three groups randomly. Each group included 6 replicates with 15 piglets each. The control group was fed with the basal diet including 0.21% tryptophan, the trentment groups (treatment groups I and II) with basal diets plus 0.1% and 0.2% tryptophan, respectively. Piglets were mixed after diet introduction for 28 d. The aggressive

  16. A gene-environment investigation on personality traits in two independent clinical sets of adult patients with personality disorder and attention deficit/hyperactive disorder.

    Science.gov (United States)

    Jacob, Christian P; Nguyen, Thuy Trang; Dempfle, Astrid; Heine, Monika; Windemuth-Kieselbach, Christine; Baumann, Katarina; Jacob, Florian; Prechtl, Julian; Wittlich, Maike; Herrmann, Martin J; Gross-Lesch, Silke; Lesch, Klaus-Peter; Reif, Andreas

    2010-06-01

    While an interactive effect of genes with adverse life events is increasingly appreciated in current concepts of depression etiology, no data are presently available on interactions between genetic and environmental (G x E) factors with respect to personality and related disorders. The present study therefore aimed to detect main effects as well as interactions of serotonergic candidate genes (coding for the serotonin transporter, 5-HTT; the serotonin autoreceptor, HTR1A; and the enzyme which synthesizes serotonin in the brain, TPH2) with the burden of life events (#LE) in two independent samples consisting of 183 patients suffering from personality disorders and 123 patients suffering from adult attention deficit/hyperactivity disorder (aADHD). Simple analyses ignoring possible G x E interactions revealed no evidence for associations of either #LE or of the considered polymorphisms in 5-HTT and TPH2. Only the G allele of HTR1A rs6295 seemed to increase the risk of emotional-dramatic cluster B personality disorders (p = 0.019, in the personality disorder sample) and to decrease the risk of anxious-fearful cluster C personality disorders (p = 0.016, in the aADHD sample). We extended the initial simple model by taking a G x E interaction term into account, since this approach may better fit the data indicating that the effect of a gene is modified by stressful life events or, vice versa, that stressful life events only have an effect in the presence of a susceptibility genotype. By doing so, we observed nominal evidence for G x E effects as well as main effects of 5-HTT-LPR and the TPH2 SNP rs4570625 on the occurrence of personality disorders. Further replication studies, however, are necessary to validate the apparent complexity of G x E interactions in disorders of human personality.

  17. Genetic polymorphisms in monoamine systems and outcome of cognitive behavior therapy for social anxiety disorder.

    Directory of Open Access Journals (Sweden)

    Evelyn Andersson

    Full Text Available OBJECTIVE: The role of genetics for predicting the response to cognitive behavior therapy (CBT for social anxiety disorder (SAD has only been studied in one previous investigation. The serotonin transporter (5-HTTLPR, the catechol-o-methyltransferase (COMT val158met, and the tryptophan hydroxylase-2 (TPH2 G-703T polymorphisms are implicated in the regulation of amygdala reactivity and fear extinction and therefore might be of relevance for CBT outcome. The aim of the present study was to investigate if these three gene variants predicted response to CBT in a large sample of SAD patients. METHOD: Participants were recruited from two separate randomized controlled CBT trials (trial 1: n = 112, trial 2: n = 202. Genotyping were performed on DNA extracted from blood or saliva samples. Effects were analyzed at follow-up (6 or 12 months after treatment for both groups and for each group separately at post-treatment. The main outcome measure was the Liebowitz Social Anxiety Scale Self-Report. RESULTS: At long-term follow-up, there was no effect of any genotype, or gene × gene interactions, on treatment response. In the subsamples, there was time by genotype interaction effects indicating an influence of the TPH2 G-703T-polymorphism on CBT short-term response, however the direction of the effect was not consistent across trials. CONCLUSIONS: None of the three gene variants, 5-HTTLPR, COMTval158met and TPH2 G-703T, was associated with long-term response to CBT for SAD. TRIAL REGISTRATION: ClinicalTrials.gov (ID-NCT0056496.

  18. Inducible gene manipulations in brain serotonergic neurons of transgenic rats.

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    Tillmann Weber

    Full Text Available The serotonergic (5-HT system has been implicated in various physiological processes and neuropsychiatric disorders, but in many aspects its role in normal and pathologic brain function is still unclear. One reason for this might be the lack of appropriate animal models which can address the complexity of physiological and pathophysiological 5-HT functioning. In this respect, rats offer many advantages over mice as they have been the animal of choice for sophisticated neurophysiological and behavioral studies. However, only recently technologies for the targeted and tissue specific modification of rat genes - a prerequisite for a detailed study of the 5-HT system - have been successfully developed. Here, we describe a rat transgenic system for inducible gene manipulations in 5-HT neurons. We generated a Cre driver line consisting of a tamoxifen-inducible CreERT2 recombinase under the control of mouse Tph2 regulatory sequences. Tissue-specific serotonergic Cre recombinase expression was detected in four transgenic TPH2-CreERT2 rat founder lines. For functional analysis of Cre-mediated recombination, we used a rat Cre reporter line (CAG-loxP.EGFP, in which EGFP is expressed after Cre-mediated removal of a loxP-flanked lacZ STOP cassette. We show an in-depth characterisation of this rat Cre reporter line and demonstrate its applicability for monitoring Cre-mediated recombination in all major neuronal subpopulations of the rat brain. Upon tamoxifen induction, double transgenic TPH2-CreERT2/CAG-loxP.EGFP rats show selective and efficient EGFP expression in 5-HT neurons. Without tamoxifen administration, EGFP is only expressed in few 5-HT neurons which confirms minimal background recombination. This 5-HT neuron specific CreERT2 line allows Cre-mediated, inducible gene deletion or gene overexpression in transgenic rats which provides new opportunities to decipher the complex functions of the mammalian serotonergic system.

  19. Brain 5-HT deficiency increases stress vulnerability and impairs antidepressant responses following psychosocial stress.

    Science.gov (United States)

    Sachs, Benjamin D; Ni, Jason R; Caron, Marc G

    2015-02-24

    Brain serotonin (5-HT) deficiency and exposure to psychosocial stress have both been implicated in the etiology of depression and anxiety disorders, but whether 5-HT deficiency influences susceptibility to depression- and anxiety-like phenotypes induced by psychosocial stress has not been formally established. Most clinically effective antidepressants increase the extracellular levels of 5-HT, and thus it has been hypothesized that antidepressant responses result from the reversal of endogenous 5-HT deficiency, but this hypothesis remains highly controversial. Here we evaluated the impact of brain 5-HT deficiency on stress susceptibility and antidepressant-like responses using tryptophan hydroxylase 2 knockin (Tph2KI) mice, which display 60-80% reductions in brain 5-HT. Our results demonstrate that 5-HT deficiency leads to increased susceptibility to social defeat stress (SDS), a model of psychosocial stress, and prevents the fluoxetine (FLX)-induced reversal of SDS-induced social avoidance, suggesting that 5-HT deficiency may impair antidepressant responses. In light of recent clinical and preclinical studies highlighting the potential of inhibiting the lateral habenula (LHb) to achieve antidepressant and antidepressant-like responses, we also examined whether LHb inhibition could achieve antidepressant-like responses in FLX-insensitive Tph2KI mice subjected to SDS. Our data reveal that using designer receptors exclusively activated by designer drugs (DREADDs) to inhibit LHb activity leads to reduced SDS-induced social avoidance behavior in both WT and Tph2KI mice. This observation provides additional preclinical evidence that inhibiting the LHb might represent a promising alternative therapeutic approach under conditions in which selective 5-HT reuptake inhibitors are ineffective.

  20. Organoids as an ex vivo model for studying the serotonin system in the murine small intestine and colon epithelium.

    Science.gov (United States)

    Tsuruta, Takeshi; Saito, Shinichi; Osaki, Yosuke; Hamada, Akihiro; Aoki-Yoshida, Ayako; Sonoyama, Kei

    2016-05-20

    Intestinal organoids were recently established as an ex vivo model of the intestinal epithelium. The present study investigated the serotonin (5-hydroxytryptamine, 5-HT) system using organoids. Organoids from murine small intestinal and colonic crypts were successfully cultured. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that small intestinal and colonic organoids express mRNAs encoding tryptophan hydroxylase-1 (TPH1) (the rate-limiting enzyme of 5-HT synthesis), serotonin reuptake transporter (SERT), 5-HT receptor (HTR)2A, HTR2B, and HTR4. SERT mRNA levels were significantly higher in the small intestine than in the colon in both the mucosal tissues and organoids, as estimated by quantitative real-time RT-PCR. Although the 5-HT concentration and levels of chromogranin A (CgA) (an enteroendocrine cell marker), TPH1, and HTR4 mRNAs were significantly higher in the colonic mucosa than the small intestinal mucosa, they were the same in small intestinal and colonic organoids. There were no significant differences in HTR2A and HTR2B mRNA levels between the small intestine and colon in either the mucosal tissues or organoids. Immunofluorescence staining showed that the number of CgA-positive cells in the colonic organoids appeared to increase upon culturing with acetate. Acetate supplementation significantly increased CgA, TPH1, and HTR4 mRNA levels in the colonic organoids. We propose that organoids are useful for investigating the 5-HT system in the intestinal epithelium, even though colonic organoids may require gut microbiota-derived factors such as short-chain fatty acids. PMID:27105910

  1. Estado de salud bucodental y presencia de lesiones orales de enfermedad injerto contra hospedador (EICH) en pacientes sometidos a trasplante alogénico de progenitores hematopoyéticos en la Región de Murcia

    OpenAIRE

    Martínez Millán, Silvia

    2016-01-01

    OBJETIVOS: 1. Evaluar el estado de salud bucodental de los pacientes sometidos alo-TPH. 2. Estudiar la frecuencia de aparición de EICH oral. 3. Estudiar la relación entre aparición de EICH oral y presencia de placa bacteriana, estado periodontal e índices de caries, ausencias y obturaciones. 4. Hacer una revisión bibliográfica sobre el protocolo de tratamiento de EICH oral. 5. Confirmar la necesidad de pautas de higiene bucodental y visitas regulares odontológicas, previas y p...

  2. An association study of suicide and candidate genes in the serotonergic system

    DEFF Research Database (Denmark)

    Buttenschøn, Henriette N; Flint, Tracey J; Foldager, Leslie;

    2013-01-01

    interaction test showed that the minor allele of rs1800532 in TPH1 has a protective effect for males younger than 35 years and females older than 50 years, whereas for the oldest male subjects, it tended to be a risk factor. We also observed a significant interaction between age-group and the 5-HTTLPR...... genotype (with and without rs25531) in SLC6A4. The long allele or high expression allele tends to have a protective effect in the middle age-group. Limitation: We only analysed a limited number of genetic variants. Conclusion: None of the analysed variants are strong risk factors. To reveal a better...

  3. Modulatory Effect of 5-Hydroxytryptamine 2A Receptor on Discharge Activities of Inspiratory Neurons in the Medial Region of Nucleus Retrofacialis of Neonatal Rats in Vitro%5-羟色胺2A受体对新生大鼠离体延髓脑片吸气神经元放电的调制

    Institute of Scientific and Technical Information of China (English)

    千智斌; 姬明丽; 齐莹; 吴中海

    2008-01-01

    目的 探讨5-羟色胺2A(5-HT2A)受体对新生大鼠延髓脑片吸气神经元放电的调制作用.方法 制作新生大鼠离体延髓脑片标本,给予灌流恒温改良Kreb's液(MKS),使用内含银一氯化银电极的吸附电极吸附舌下神经根,稳定记录舌下神经根呼吸相关节律性放电活动(RRDA)后,使用微电极以细胞外记录方式在面神经后核内侧区同步记录吸气神经元放电.同步记录舌下神经根RRDA和吸气神经元放电后,用含40μmol/L 5-HT2A受体特异激动剂2,5-二甲氧基-4-碘苯基丙烷-2胺盐酸盐(DOI)的MKS充分灌流延髓脑片,记录吸气神经元放电活动变化,冲洗至RRDA和吸气神经元放电基本恢复,用含5-HT2A受体特异拮抗剂酮舍林的MKS灌流脑片,记录吸气神经元放电活动变化.结果 使用DOI激活5-HT2A受体后,吸气神经元放电时程(TI)为(0.86±0.07)s,呼气时程(TE)为(10.78±1.06)s,呼吸周期(RC)为(11.79±1.64)s,吸气神经元放电积分幅度(IA)为(357.98±37.21)(μV·s),放电峰频率(PF)为(37.83±3.66)Hz,对照组分别为(0.68±0.06)s、(13.89±2.14)s、(14.77±1.92)s、(273.57±24.39)(μV·s)和(29.92±4.50)Hz, DOI组与对照组比较均有显著差异(Pa<0.01).对吸气神经元放电有兴奋作用.应用酮舍林后,缩短TI为(0.55±0.07)s,延长TE为(18.43±3.28)s, RC为(20.17±2.91)s, IA减为(214.37±33.52)(μV·s),PF为(22.17±3.92)Hz,与对照组和DOI组比较均有显著差异(Pa<0.01).对吸气神经元放电有抑制作用.结论 5-HT2A受体参与调节新生大鼠延髓脑片吸气神经元放电活动.%Objective To explore the modulatory effect of 5-HT2A receptors on the discharge activities of inspiratory neurons in medial region of nucleus retrofacialis of neonatal rats. Methods Experiments were performed in vitro brainstem slice preparations from neonatal rats. These preparations included the medial region of nucleus retrofacialis with the hypoglossal nerve rootlets retained. The rhythmic

  4. 色氨酸羟化酶2启动子区基因多态性与酒依赖的关联性研究%Association study on tryptophan hydroxylase 2 promoter region gene polymorphisms with alcohol dependence

    Institute of Scientific and Technical Information of China (English)

    李秋凤; 唐春玲; 胡建

    2015-01-01

    目的 探讨中国北方汉族人群色氨酸羟化酶2 (TPH2)启动子区基因(rs4570625、rs11178997)多态性与酒依赖及酒依赖的抑郁症状是否存在关联性.方法 应用聚合酶链式反应(PCR)扩增技术及基因序列测序方法,对60例酒依赖患者(患者组)和62例正常人群(对照组)的TPH2启动子区基因位点rs4570625和rs11178997的基因型和等位基因频率进行测定.应用24项汉密尔顿抑郁量表(HAMD)评定酒依赖患者的抑郁症状,并分析酒依赖的抑郁症状与TPH2基因多态性的关联性.结果 rs4570625的基因型(G/G、G/T、T/T)分布频率在两组之间差异无统计学意义(x2=5.078,P>0.05),但其等位基因(G和T)频率分布在患者组和对照组之问差异有统计学意义(x2=5.280,P<0.05).rs4570625的等位基因分布频率与酒依赖的抑郁症状之间差异也存在统计学意义(P<0.05),但其基因型分布频率与酒依赖的抑郁症状之间差异无统计学意义(P>0.05).rs11178997的基因型(A/A、A/T、T/T)和等位基因(A和T)分布频率在患者组和对照组之间均差异无统计学意义(均P>0.05),且与酒依赖的抑郁症状之间均差异无统计学意义(均P>0.05).结论 中国北方汉族人群TPH2启动子区基因rs4570625的多态性与酒依赖和酒依赖的抑郁症状有关,而且T等位基因的携带是易感者,但rs1117899的多态性与酒依赖及其抑郁症状并无相关性.%Objective To investigate the association of single nucleotide polymorphisms (SNPs) of loci rs4570625,rs11178997 at promoter region of tryptophan hydroxylase 2 (TPH2) genes with alcohol dependence and depressive symptom in the alcohol-dependent subjects in north Chinese Han people.Methods Genotype and allele frequencies of the TPH2 rs4570625 and rs1 1178997 polymorphisms were examined in 60 alcohol-dependent subjects (patient group) and 62 normal controls (control group) by Polymerase Chain Reaction (PCR) amplification and DNA sequencing

  5. The crystal structure of tryptophan hydroxylase with bound amino acid substrate

    DEFF Research Database (Denmark)

    Windahl, Michael Skovbo; Petersen, Charlotte Rode; Christensen, Hans Erik Mølager;

    2008-01-01

    acid hydroxylase with bound natural amino acid substrate. The iron coordination can be described as distorted trigonal bipyramidal coordination with His273, His278, and Glu318 (partially bidentate) and one imidazole as ligands. The tryptophan stacks against Pro269 with a distance of 3.9 Å between...... of the neurotransmitter and hormone serotonin (5-hydroxytryptamine). We have determined the 1.9 Å resolution crystal structure of the catalytic domain (Δ1−100/Δ415−445) of chicken TPH isoform 1 (TPH1) in complex with the tryptophan substrate and an iron-bound imidazole. This is the first structure of any aromatic amino......124−Asp139 and Ile367−Thr369 close around the active site. Similar structural changes are seen in the catalytic domain of phenylalanine hydroxylase (PAH) upon binding of substrate analogues norleucine and thienylalanine to the PAH·BH4 complex. In fact, the chicken TPH1·Trp·imidazole structure...

  6. A Run-Length Encoding Approach for Path Analysis of C. elegans Search Behavior

    Science.gov (United States)

    Kim, Hongkyun; Furst, Jacob

    2016-01-01

    The nematode Caenorhabditis elegans explores the environment using a combination of different movement patterns, which include straight movement, reversal, and turns. We propose to quantify C. elegans movement behavior using a computer vision approach based on run-length encoding of step-length data. In this approach, the path of C. elegans is encoded as a string of characters, where each character represents a path segment of a specific type of movement. With these encoded string data, we perform k-means cluster analysis to distinguish movement behaviors resulting from different genotypes and food availability. We found that shallow and sharp turns are the most critical factors in distinguishing the differences among the movement behaviors. To validate our approach, we examined the movement behavior of tph-1 mutants that lack an enzyme responsible for serotonin biosynthesis. A k-means cluster analysis with the path string-encoded data showed that tph-1 movement behavior on food is similar to that of wild-type animals off food. We suggest that this run-length encoding approach is applicable to trajectory data in animal or human mobility data. PMID:27462364

  7. A Microarray Study of Middle Cerebral Occlusion Rat Brain with Acupuncture Intervention

    Directory of Open Access Journals (Sweden)

    Chao Zhang

    2015-01-01

    Full Text Available Microarray analysis was used to investigate the changes of gene expression of ischemic stroke and acupuncture intervention in middle cerebral artery occlusion (MCAo rat brain. Results showed that acupuncture intervention had a remarkable improvement in neural deficit score, cerebral blood flow, and cerebral infarction volume of MCAo rats. Microarray analysis showed that a total of 627 different expression genes were regulated in ischemic stroke. 417 genes were upregulated and 210 genes were downregulated. A total of 361 different expression genes were regulated after acupuncture intervention. Three genes were upregulated and 358 genes were downregulated. The expression of novel genes after acupuncture intervention, including Tph1 and Olr883, was further analyzed by Real-Time Quantitative Polymerase Chain Reaction (RT-PCR. Upregulation of Tph1 and downregulation of Olr883 indicated that the therapeutic effect of acupuncture for ischemic stroke may be closely related to the suppression of poststroke depression and regulation of olfactory transduction. In conclusion, the present study may enrich our understanding of the multiple pathological process of ischemic brain injury and indicate possible mechanisms of acupuncture on ischemic stroke.

  8. Melatonin Synthesis: Acetylserotonin O-Methyltransferase (ASMT) Is Strongly Expressed in a Subpopulation of Pinealocytes in the Male Rat Pineal Gland.

    Science.gov (United States)

    Rath, Martin F; Coon, Steven L; Amaral, Fernanda G; Weller, Joan L; Møller, Morten; Klein, David C

    2016-05-01

    The rat pineal gland has been extensively used in studies of melatonin synthesis. However, the cellular localization of melatonin synthesis in this species has not been investigated. Here we focus on the localization of melatonin synthesis using immunohistochemical methods to detect the last enzyme in melatonin synthesis, acetylserotonin O-methyltransferase (ASMT), and in situ hybridization techniques to study transcripts encoding ASMT and two other enzymes in melatonin synthesis, tryptophan hydroxylase (TPH)-1 and aralkylamine N-acetyltransferase. In sections of the rat pineal gland, marked cell-to-cell differences were found in ASMT immunostaining intensity and in the abundance of Tph1, Aanat, and Asmt transcripts. ASMT immunoreactivity was localized to the cytoplasm in pinealocytes in the parenchyma of the superficial pineal gland, and immunopositive pinealocytes were also detected in the pineal stalk and in the deep pineal gland. ASMT was found to inconsistently colocalize with S-antigen, a widely used pinealocyte marker; this colocalization was seen in cells throughout the pineal complex and also in displaced pinealocyte-like cells of the medial habenular nucleus. Inconsistent colocalization between ASMT and TPH protein was also detected in the pineal gland. ASMT protein was not detected in extraepithalamic parts of the central nervous system or in peripheral tissues. The findings in this report are of special interest because they provide reason to suspect that melatonin synthesis varies significantly among individual pinealocytes. PMID:26950199

  9. Serotonin deficiency exacerbates acetaminophen-induced liver toxicity in mice.

    Science.gov (United States)

    Zhang, Jingyao; Song, Sidong; Pang, Qing; Zhang, Ruiyao; Zhou, Lei; Liu, Sushun; Meng, Fandi; Wu, Qifei; Liu, Chang

    2015-01-29

    Acetaminophen (APAP) overdose is a major cause of acute liver failure. Peripheral 5-hydroxytryptamine (serotonin, 5-HT) is a cytoprotective neurotransmitter which is also involved in the hepatic physiological and pathological process. This study seeks to investigate the mechanisms involved in APAP-induced hepatotoxicity, as well as the role of 5-HT in the liver's response to APAP toxicity. We induced APAP hepatotoxicity in mice either sufficient of serotonin (wild-type mice and TPH1-/- plus 5- Hydroxytryptophan (5-HTP)) or lacking peripheral serotonin (Tph1-/- and wild-type mice plus p-chlorophenylalanine (PCPA)). Mice with sufficient 5-HT exposed to acetaminophen have a significantly lower mortality rate and a better outcome compared with mice deficient of 5-HT. This difference is at least partially attributable to a decreased level of inflammation, oxidative stress and endoplasmic reticulum (ER) stress, Glutathione (GSH) depletion, peroxynitrite formation, hepatocyte apoptosis, elevated hepatocyte proliferation, activation of 5-HT2B receptor, less activated c-Jun NH₂-terminal kinase (JNK) and hypoxia-inducible factor (HIF)-1α in the mice sufficient of 5-HT versus mice deficient of 5-HT. We thus propose a physiological function of serotonin that serotonin could ameliorate APAP-induced liver injury mainly through inhibiting hepatocyte apoptosis ER stress and promoting liver regeneration.

  10. Gestational Diabetes Mellitus From Inactivation of Prolactin Receptor and MafB in Islet β-Cells.

    Science.gov (United States)

    Banerjee, Ronadip R; Cyphert, Holly A; Walker, Emily M; Chakravarthy, Harini; Peiris, Heshan; Gu, Xueying; Liu, Yinghua; Conrad, Elizabeth; Goodrich, Lisa; Stein, Roland W; Kim, Seung K

    2016-08-01

    β-Cell proliferation and expansion during pregnancy are crucial for maintaining euglycemia in response to increased metabolic demands placed on the mother. Prolactin and placental lactogen signal through the prolactin receptor (PRLR) and contribute to adaptive β-cell responses in pregnancy; however, the in vivo requirement for PRLR signaling specifically in maternal β-cell adaptations remains unknown. We generated a floxed allele of Prlr, allowing conditional loss of PRLR in β-cells. In this study, we show that loss of PRLR signaling in β-cells results in gestational diabetes mellitus (GDM), reduced β-cell proliferation, and failure to expand β-cell mass during pregnancy. Targeted PRLR loss in maternal β-cells in vivo impaired expression of the transcription factor Foxm1, both G1/S and G2/M cyclins, tryptophan hydroxylase 1 (Tph1), and islet serotonin production, for which synthesis requires Tph1. This conditional system also revealed that PRLR signaling is required for the transient gestational expression of the transcription factor MafB within a subset of β-cells during pregnancy. MafB deletion in maternal β-cells also produced GDM, with inadequate β-cell expansion accompanied by failure to induce PRLR-dependent target genes regulating β-cell proliferation. These results unveil molecular roles for PRLR signaling in orchestrating the physiologic expansion of maternal β-cells during pregnancy. PMID:27217483

  11. Exposure to serotonin adversely affects oligodendrocyte development and myelination in vitro.

    Science.gov (United States)

    Fan, Lir-Wan; Bhatt, Abhay; Tien, Lu-Tai; Zheng, Baoying; Simpson, Kimberly L; Lin, Rick C S; Cai, Zhengwei; Kumar, Praveen; Pang, Yi

    2015-05-01

    Serotonin (5-hydroxytryptamine, 5-HT) has been implicated to play critical roles in early neural development. Recent reports have suggested that perinatal exposure to selective serotonin reuptake inhibitors (SSRIs) resulted in cortical network miswiring, abnormal social behavior, callosal myelin malformation, as well as oligodendrocyte (OL) pathology in rats. To gain further insight into the cellular and molecular mechanisms underlying SSRIs-induced OL and myelin abnormalities, we investigated the effect of 5-HT exposure on OL development, cell death, and myelination in cell culture models. First, we showed that 5-HT receptor 1A and 2A subtypes were expressed in OL lineages, using immunocytochemistry, Western blot, as well as intracellular Ca(2+) measurement. We then assessed the effect of serotonin exposure on the lineage development, expression of myelin proteins, cell death, and myelination, in purified OL and neuron-OL myelination cultures. For pure OL cultures, our results showed that 5-HT exposure led to disturbance of OL development, as indicated by aberrant process outgrowth and reduced myelin proteins expression. At higher doses, such exposure triggered a development-dependent cell death, as immature OLs exhibited increasing susceptibility to 5-HT treatment compared to OL progenitor cells (OPC). We showed further that 5-HT-induced immature OL death was mediated at least partially via 5-HT2A receptor, since cell death could be mimicked by 5-HT2A receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride, (±)-2,5-dimethoxy-4-iodoamphetamine hydrochloride, but atten-uated by pre-treatment with 5-HT2A receptor antagonist ritanserin. Utilizing a neuron-OL myelination co-culture model, our data showed that 5-HT exposure significantly reduced the number of myelinated internodes. In contrast to cell injury observed in pure OL cultures, 5-HT exposure did not lead to OL death or reduced OL density in neuron-OL co-cultures. However, abnormal

  12. Polymorphisms of serotonin receptor 2A and 2C genes and COMT in relation to obesity and type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    Sofia I I Kring

    Full Text Available BACKGROUND: Candidate genes of psychological importance include 5HT2A, 5HT2C, and COMT, implicated in the serotonin, noradrenaline and dopamine pathways, which also may be involved in regulation of energy balance. We investigated the associations of single nucleotide polymorphisms (SNPs of these genes with obesity and metabolic traits. METHODOLOGY/PRINCIPAL FINDINGS: In a population of 166 200 young men examined at the draft boards, obese men (n = 726, BMI> or =31.0 kg/m(2 and a randomly selected group (n = 831 were re-examined at two surveys at mean ages 46 and 49 years (S-46, S-49. Anthropometric, physiological and biochemical measures were available. Logistic regression analyses were used to assess age-adjusted odds ratios. No significant associations were observed of 5HT2A rs6311, 5HT2C rs3813929 and COMT rs4680 with obesity, except that COMT rs4680 GG-genotype was associated with fat-BMI (OR = 1.08, CI = 1.01-1.16. The SNPs were associated with a number of physiological variables; most importantly 5HT2C rs3813929 T-allele was associated with glucose (OR = 4.56, CI = 1.13-18.4 and acute insulin response (OR = 0.65, CI = 0.44-0.94 in S-49. COMT rs4680 GG-genotype was associated with glucose (OR = 1.04, CI = 1.00-1.09. Except for an association between 5HT2A rs6311 and total-cholesterol at both surveys, significant in S-46 (OR = 2.66, CI = 1.11-6.40, no significant associations were observed for the other phenotypes. Significant associations were obtained when combined genotype of 5HT2C rs3813929 and COMT rs4680 were examined in relation to BMI (OR = 1.12, CI = 1.03-1.21, fat-BMI (OR = 1.22, CI = 1.08-1.38, waist (OR = 1.13, CI = 1.04-1.22, and cholesterol (OR = 5.60, CI = 0.99-31.4. Analyses of impaired glucose tolerance (IGT and type 2 diabetes (T2D revealed, a 12.3% increased frequency of 5HT2C rs3813929 T-allele and an 11.6% increased frequency of COMT rs4680 GG-genotype in individuals with IGT or T2D (chi(2, p = 0.05 and p = 0

  13. 5- Hydroxytryptamine- inhibiting property of Feverfew: role of parthenolide content

    Institute of Scientific and Technical Information of China (English)

    Aniruddha DATFA; S K SINGH; Amarjit SINGH; Shivani MITIRA

    2000-01-01

    AIM: To study the mechanism of antimigraine activity of Tanacetum parthenium (Feverfew), its extracts and parthenolide, a component of Feverfew, by observing their effect on 5-HT storage and release, and stimulation of 5-HT2B and 5-HT2A receptors. Also to standardize a dosage form of Feverfew with respect to its parthenolide content. METHODS: Isomeaic responses to 5-HT and an indirect acting serotonergic, d-fenfluramine, were obtained on rat fundus and ileum. In one set of experiments the effect of dichloromethane extract of Feveffew and parthenolide was observed on the above. The extract was then thermally degraded upto 10 %, 23 %, and 33 % with respect to its parthenolide content by keeping at 60 ℃ and 75 % relative humidity and the expe nments were reperepeated. In another set of experiments rats were fed with 20 rog/kg Feverfew powder (equivalent to a human dose of 500 pg parthenolide per day) for 30 d or were ip injected with parthenolide (23.4 μg/day) for 7 d. In the same set of experiments one group of rats were fed with 15 % and 77 % degraded Feverfew powder in the same dose as mentioned above. After 30 days the effects of the above were observed on 5-HT and d-fenfluramine. Feveffew was specially formulated and tested for stability under accelerated conditions. RESULTS: Parthenolide (1 × 10-5 mol/L) non-competitively antagonised the effects of d-fenfluramine but had nosignificant effect on 5-HT2B and 5-HT2A receptors in rat fundus and ileum at 30 ain which turned significant on increasing the incubation time to 1.5 h, in rat fundus. Parthenolide (5 × 10-5 mol/L) followed the same trend.. However, Feverfew extract (1 × 10-5 mol/L) potently and directly blocked 5-HT2B and 5-HT2A receptors and neuronally released 5-HT. At 5 × 10-5 mol/L the extract potently and irreversibly blocked the above. Both parthenolide and Feverfew extract showed a time-dependency in their action. The extract when degraded thermally upto 10 % could significantly block the 5-HT

  14. Differential effects of three 5-HT receptor antagonists on the performance of rats in attentional and working memory tasks.

    Science.gov (United States)

    Ruotsalainen, S; Sirviö, J; Jäkälä, P; Puumala, T; MacDonald, E; Riekkinen, P

    1997-05-01

    The effects of three different serotonin (5-HT) receptor antagonists (ketanserin, methysegide, methiothepin) in the modulation of attention, working memory and behavioural activity were investigated in this study by assessing the performance of rats in two separate cognitive models; the 5-choice serial reaction time (5-CSRT) task, which measures attention, and the delayed non-matching to position (DNMTP) task, which measures working memory. Methysergide and methiothepin bind at the 5-HT1 and 5-HT2 as well as the 5-HT5-7 receptors, with varying degrees of selectivity, and ketanserin binds at the 5-HT2A receptors rather selectively. None of these agents bind to any significant extent to 5-HT3 or 5-HT4 receptors. In the 5-CSRT task, neither methiothepin (0.15 mg/kg) nor ketanserin (1.0 and 3.0 mg/kg) impaired the choice accuracy of rats, although they induced sedation. The low doses of methysergide (1.5 and 3.0 mg/kg) slightly increased the behavioural activity of rats, whereas the high dose of methysergide (15.0 mg/kg) reduced behavioural activity and slightly reduced choice accuracy of the rats in the attentional task (monitoring of visual stimuli) under the baseline conditions or curtailed stimulus duration. This effect was not augmented at the reduced stimulus intensity. These findings suggest that the high dose of methysergide did not interfere with the visual discrimination of rats. Furthermore, methysergide did not reduce motivation for this task, since it did not increase food collection latencies. In the DNMTP task, methiothepin (0.15 mg/kg) induced a delay non-dependent deficit in choice accuracy. This could be due to an impaired alternation ability or akinesia, which increases an actual delay between sample and choice. Methiothepin (0.15 mg/kg) also interfered with behavioural activity of rats. Interestingly, ketanserin (1.0 mg/kg and 3.0 mg/kg) and methysergide (3.0-15.0 mg/kg) neither impaired the choice accuracy nor reduced the behavioural activity of

  15. Mechanisms of the antinociceptive action of (− Epicatechin obtained from the hydroalcoholic fraction of Combretum leprosum Mart & Eic in rodents

    Directory of Open Access Journals (Sweden)

    Lopes Luciano da

    2012-07-01

    Full Text Available Abstract Background The mechanisms of the antinociceptive activity of (− epicatechin (EPI, a compound isolated from the hydroalcoholic fraction of Combreum leprosum Mart & Eicher. Methods were assessed in the model of chemical nociception induced by glutamate (20 μmol/paw. To evaluate the mechanisms involved, the animals , male Swiss mice (25-30 g, received EPI (50 mg/kg p.o. after pretreatment with naloxone (2 mg/kg s.c. opioid antagonist, glibenclamide (2 mg/kg s.c. antagonist K + channels sensitive to ATP, ketanserin (0.3 mg/kg s.c. antagonist of receptor 5-HT2A, yoimbine (0.15 mg/kg s.c. α2 adrenergic receptor antagonist, pindolol (1 mg/kg s.c. 5-HT1a/1b receptor antagonist, atropine (0.1 mg/kg s.c. muscarinic antagonist and caffeine (3 mg/kg s.c. adenosine receptor antagonist, ondansetron (0.5 mg/kg s.c. for 5-HT3 receptor and L-arginine (600 mg/kg i.p.. Results The antinociceptive effect of EPI was reversed by pretreatment with naloxone and glibenclamide, ketanserin, yoimbine, atropine and pindolol, which demonstrates the involvement of opioid receptors and potassium channels sensitive to ATP, the serotoninergic (receptor 5HT1A and 5HT2A, adrenergic (receptor alpha 2 and cholinergic (muscarinic receptor systems in the activities that were observed. The effects of EPI, however, were not reversed by pretreatment with caffeine, L-arginine or ondansetron, which shows that there is no involvement of 5HT3 receptors or the purinergic and nitrergic systems in the antinociceptive effect of EPI. In the Open Field and Rotarod test, EPI had no significant effect, which shows that there was no central nervous system depressant or muscle relaxant effect on the results. Conclusions This study demonstrates that the antinociceptive activity of EPI in the glutamate model involves the participation of the opioid system, serotonin, adrenergic and cholinergic.

  16. Genipin is active via modulating monoaminergic transmission and levels of brain-derived neurotrophic factor (BDNF) in rat model of depression.

    Science.gov (United States)

    Wang, Q-S; Tian, J-S; Cui, Y-L; Gao, S

    2014-09-01

    Genipin, an important bioactive component from Gardenia jasminoides Eills, was demonstrated to possess antidepressant-like effects in a previous study. However, the molecular mechanism of antidepressant-like effects on genipin was not clear. The present study aimed to investigate the possible mechanism of antidepressant-like effects on genipin with a chronic unpredictable mild stress (CUMS)-induced depression model in rats. In CUMS-induced depressive rats, bodyweight and 1% sucrose consumption decreased significantly compared with the normal control group. Furthermore, these changes could be significantly reversed by genipin application. The levels of 5-hydroxytryptamine (5-HT), norepinephrine (NE) in the hippocampus decreased and the level of 5-hydroxyindole acetic acid (5-HIAA) increased in the CUMS-induced depressive rats. However, pre-treatments with genipin significantly increased the levels of 5-HT, NE and decreased the level of 5-HIAA in the hippocampus. The concentration of cAMP in the hippocampus was increased by genipin compared to the CUMS-exposed model group. The mRNA expressions of 5-hydroxytryptamine 1A receptor (5-HT1AR), cAMP response element binding protein (CREB) and brain-derived neurotrophic factor (BDNF) in rats were decreased exposed to CUMS, which were reversed by genipin-treated rats exposed to CUMS. Compared to the CUMS-exposed model group, the mRNA expression of 5-hydroxytryptamine 2A receptor (5-HT(2A)R) was decreased significantly by genipin-treated rats. The mRNA and protein expression of CREB, BDNF were increased in genipin-treated rats compared to the CUMS-exposed model group. Moreover, the levels of corticosterone in serum were decreased by genipin-treated compared to the CUMS-exposed model group. These results suggest that the possible mechanism of antidepressant-like effects on genipin, at least in one part, resulted from monoaminergic neurotransmitter system and the potential dysfunctional regulation of the post-receptor signaling

  17. Association analysis of tryptophan hydroxylase-2 gene polymorphism with antisocial personality disorder and impulsivity%色氨酸羟化酶2基因多态性与反社会人格障碍及其冲动行为的关联研究

    Institute of Scientific and Technical Information of China (English)

    吴岩峰; 郑大同; 谭钊安; 柯晓燕; 张建平; 茆正洪; 曾彦英

    2010-01-01

    Objective To study the association of tryptophan hydroxylase-2 (TPH2) gene polymorphism and antisocial personality disorder (ASPD) and its impulsivity in Chinese Han population. Methods The single nucleotide polymorphism (SNPs) of TPH2 in transcriptional control region,-703G/T,was analyzed by PCR-RFLP genotyping assay in 117 ASPD patients and 142 healthy controls. Barratt Impulsiveness Scale-11 (BIS-11) was used to evaluate the impulsivity of subjects. Results There were significant differences between ASPD and controis on genotype and allele frequencies of TPH2-703G/T (x2 = 7.73, P < 0.05; x2 = 5.12, P < 0.05). The GG genotype and G allele were positively associated with ASPD(OR = 1.458,95% CI = 1.080 ~ 1.968 ;OR = 1.479,95% CI = 1.045 ~ 2.094). The scores of BIS-11 and its factors in GG genotype group((71.28 ± 7.50), (19.60 ±3.41), (25.73 ± 4.92), (25.95 ± 4.77) ) were higher than GT genotype group (( 66.23 ± 8.06), (17.79 ±3.02) ,(23.06 ±3.84) ,(25.38 ±4.97)) and TT genotype group((66.55 ±8.49),(18.50 ±3.35),(23.45 ±4.08), (24.97 ± 4.90)), but only the difference of BIS-11 total scores, the attention and motor factor scores among three groups were statistically significant (P<0.05). The scores of BIS-11 and its factors in G allele group ((69.38 ±8.04), (18.92 ± 3.36), (24.73 ±4. 69), (25.73 ±4.82)) were higher than T genotype group ((66.41 ±8.22),(17.98 ±3.26),(23.27 ±3.94), (25.15 ±4.89)),however,only the difference of BIS-11 total scores, the attention and motor factor scores between two groups were statistically significant.Conclusion TPH2-703G/T polymorphism may be association with ASPD in Chinese Han population. The GG genotype and G allele may be the risk factors of ASPD and impulsivity.%目的 探讨色氨酸羟化酶2(Tryptophan Hydroxylase-2,TPH2)基因多态性与反社会人格障碍(Antisocial Personality Disorder,ASPD)及其冲动行为的关系.方法 选取TPH2基因启动子上游多态-703G/T(rs4570625),采

  18. Involvement of tryptophan hydroxylase 2 gene polymorphisms in susceptibility to tic disorder in Chinese Han population

    Directory of Open Access Journals (Sweden)

    Zheng Ping

    2013-01-01

    Full Text Available Abstract Background Tryptophan hydroxylase-2 (TPH2 is a potential candidate gene for screening tic disorder (TD. Methods A case–control study was performed to examine the association between the TPH2 gene and TD. The Sequenom® Mass ARRAY iPLEX GOLD System was used to genotype two single nucleotide polymorphisms (SNPs of the TPH2 gene in 149 TD children and in 125 normal controls. Results For rs4565946, individuals with the TT genotype showed a significantly higher risk of TD than those with TC plus CC genotypes [odds ratio (OR =3.077, 95% confidence interval (CI: 1.273–7.437; P = 0.009], as did male TD children with the TT genotype (OR = 3.228, 95% CI: 1.153–9.040; P = 0.020. The G allele of rs4570625 was significantly more frequent in TD children with higher levels of tic symptoms (Yale Global Tic Severity Scale, YGTSS than those in controls among the male children (OR = 1.684, 95%: 1.097–2.583; P = 0.017]. TD children with severe tic symptoms had significantly higher frequencies of rs4546946 TT genotype than did normal controls in boys (OR = 3.292, 95% CI: 1.139–9.513; P = 0.022. We also found that genotype distributions of both SNPs were different between the Asian and European populations. Conclusions Our results indicated that the TT genotype of rs4565946 is a potential genetic risk factor for TD, and the allele G of rs4570625 might be associated with the severity of tic symptoms in boys. These polymorphisms might be susceptibility loci for TD in the Chinese Han population. Because of the confounding of co-existing attention deficit hyperactivity disorder (ADHD,these findings need to be confirmed by studies in much larger samples.

  19. Phospholipase D-mediated hypersensitivity at central synapses is associated with abnormal behaviours and pain sensitivity in rats exposed to prenatal stress.

    Science.gov (United States)

    Sun, Liting; Gooding, Hayley L; Brunton, Paula J; Russell, John A; Mitchell, Rory; Fleetwood-Walker, Sue

    2013-11-01

    Adverse events at critical stages of development can lead to lasting dysfunction in the central nervous system (CNS). To seek potential underlying changes in synaptic function, we used a newly developed protocol to measure alterations in receptor-mediated Ca(2+) fluorescence responses of synaptoneurosomes, freshly isolated from selected regions of the CNS concerned with emotionality and pain processing. We compared adult male controls and offspring of rats exposed to social stress in late pregnancy (prenatal stress, PS), which showed programmed behavioural changes indicating anxiety, anhedonia and pain hypersensitivity. We found corresponding increases, in PS rats compared with normal controls, in responsiveness of synaptoneurosomes from frontal cortex to a glutamate receptor (GluR) agonist, and from spinal cord to activators of nociceptive afferents. Through a combined pharmacological and biochemical strategy, we found evidence for a role of phospholipase D1 (PLD1)-mediated signalling, that may involve 5-HT2A receptor (5-HT2AR) activation, at both levels of the nervous system. These changes might participate in underpinning the enduring alterations in behaviour induced by PS. PMID:23932932

  20. GABAA receptors, but not dopamine, serotonin or NMDA receptors, are increased in the frontal cortex from schizophrenic subjects

    International Nuclear Information System (INIS)

    Full text: Having shown changed 5HT2A receptor density in the frontal cortex (FC) from schizophrenic subjects (1) we now report on further studies of the molecular neuroanatomy of the FC in schizophrenia. We used in situ radioligand binding and autoradiography to measure the density of [3H]8OH-DPAT (1 nM) binding (5HT1A receptors) and [3H]GR113808 (2.4nM) binding (5HT4 receptors) in Brodmann's areas (BA) 8, 9 and 10 from 10 schizophrenic and 10 controls subjects. In addition, [3H]muscimol (100 nM) binding (GABAA receptors), [3H]TCP (20nM) binding (NMDA receptors), [3H]SCH 23390 (3nM) binding (DA D1like receptors) and [3H]YM-09151-2 (4nM) binding (DA D2-like receptors) was measured in BA 9 from 17 schizophrenic and 17 control subjects. Subjects were matched for age and sex and the post-mortem interval for tissue collection did not differ. There was a significant increase (18%) in the density of GABAA receptors in BA 9 from subjects with schizophrenia (p<0.05) with no change in NMDA, dopamine or serotonin receptors. These data support the hypothesis that there are selective changes in neurotransmitter receptors in the FC of subjects with schizophrenia. It is not yet clear if such changes contribute to the pathology of the illness. Copyright (1998) Australian Neuroscience Society

  1. Psychosis in Parkinson's Disease: Epidemiology, Pathophysiology, and Management.

    Science.gov (United States)

    Chang, Anna; Fox, Susan H

    2016-07-01

    Psychotic symptoms are common in Parkinson's disease (PD) and are associated with poorer quality of life and increased caregiver burden. PD psychosis is correlated with several factors, such as more advanced disease, cognitive impairment, depression, and sleep disorders. The underlying causes of psychosis in PD thus involve a complex interplay between exogenous (e.g., drugs, intercurrent illnesses) and endogenous (e.g., PD disease pathology) factors. Current theories of the pathophysiology of PD psychosis have come from several neuropathological and neuroimaging studies that implicate pathways involving visual processing and executive function, including temporo-limbic structures and neocortical gray matter with altered neurotransmitter functioning (e.g., dopamine, serotonin, and acetylcholine). Treatment of PD psychosis requires a step-wise process, including initial careful investigation of treatable triggering conditions and a comprehensive evaluation with adjustment of PD medications and/or initiation of specific antipsychotic therapies. Clozapine remains the only recommended drug for the treatment of PD psychosis; however, because of regular blood monitoring, quetiapine is usually first-line therapy, although less efficacious. Emerging studies have focused on agents involving other neurotransmitters, including the serotonin 5-HT2A receptor inverse agonist pimavanserin, cholinesterase inhibitors, and antidepressants and anxiolytics. PMID:27312429

  2. [New pharmacological approaches to the treatment of schizophrenia].

    Science.gov (United States)

    Uzbay, I Tayfun

    2009-01-01

    Schizophrenia is a serious mental disorder with a challenging rational pharmacotherapy. Neurochemical transmission in the dopaminergic system, especially via D2 receptors, and related changes in postsynaptic signal transduction are very important in both the formation of schizophrenia and current pharmacotherapeutic treatment with antipsychotic drugs. Blocking the serotonergic 5-HT2A and 5-HT2C receptors is growing growing importance with regard to the action mechanisms of new generation antipsychotic medications. Recent preclinical and clinical data show that dysfunction of central neurotrophins, such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurophin-3 (NT-3) might contribute to impaired brain development and neuroplasticity, leading to schizophrenia. In addition, some recent studies suggest that there is an important relationship between alcohol and substance addiction, and schizophrenia. There is also some preclinical data indicating that the central nitrergic system and agmatine(3/4)a biologically active agent produced after decarboxylation of arginine(3/4)might be interesting and important targets for understanding the etiopathogenesis of schizophrenia and for development of new drugs. Selective dopamine D3 receptor antagonists, specific agonists for metabotropic and NMDA receptors of the glutamatergic system, and nicotinic alpha-7 receptor agonists were reported in preclinical and a limited number of clinical studies as potential new targets for schizophrenia treatment. In this review, new advances in the pharmacotherapy of schizophrenia and possible new targets are discussed in the light of the current literature.

  3. Linoleic acid derivative DCP-LA ameliorates stress-induced depression-related behavior by promoting cell surface 5-HT1A receptor translocation, stimulating serotonin release, and inactivating GSK-3β.

    Science.gov (United States)

    Kanno, Takeshi; Tanaka, Akito; Nishizaki, Tomoyuki

    2015-04-01

    Impairment of serotonergic neurotransmission is the major factor responsible for depression and glycogen synthase kinase 3β (GSK-3β) participates in serotonergic transmission-mediated signaling networks relevant to mental illnesses. In the forced-swim test to assess depression-like behavior, the immobility time for mice with restraint stress was significantly longer than that for nonstressed control mice. Postsynaptic cell surface localization of 5-HT1A receptor, but not 5-HT2A receptor, in the hypothalamus for mice with restraint stress was significantly reduced as compared with that for control mice, which highly correlated to prolonged immobility time, i.e., depression-like behavior. The linoleic acid derivative 8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid (DCP-LA) restored restraint stress-induced reduction of cell surface 5-HT1A receptor and improved depression-like behavior in mice with restraint stress. Moreover, DCP-LA stimulated serotonin release from hypothalamic slices and cancelled restraint stress-induced reduction of GSK-3β phosphorylation at Ser9. Taken together, the results of the present study indicate that DCP-LA could ameliorate depression-like behavior by promoting translocation of 5-HT1A receptor to the plasma membrane on postsynaptic cells, stimulating serotonin release, and inactivating GSK-3β. PMID:24788685

  4. Development and validation of stability indicating UPLC assay method for ziprasidone active pharma ingredient

    Directory of Open Access Journals (Sweden)

    Sonam Mittal

    2012-01-01

    Full Text Available Background: Ziprasidone, a novel antipsychotic, exhibits a potent highly selective antagonistic activity on D2 and 5HT2A receptors. Literature survey for ziprasidone revealed several analytical methods based on different techniques but no UPLC method has been reported so far. Aim: Aim of this research paper is to present a simple and rapid stability indicating isocratic, ultra performance liquid chromatographic (UPLC method which was developed and validated for the determination of ziprasidone active pharmaceutical ingredient. Forced degradation studies of ziprasidone were studied under acid, base, oxidative hydrolysis, thermal stress and photo stress conditions. Materials and Methods: The quantitative determination of ziprasidone drug was performed on a Supelco analytical column (100×2.1 mm i.d., 2.7 ΅m with 10 mM ammonium acetate buffer (pH: 6.7 and acetonitrile (ACN as mobile phase with the ratio (55:45-Buffer:ACN at a flow rate of 0.35 ml/ min. For UPLC method, UV detection was made at 318 nm and the run time was 3 min. Developed UPLC method was validated as per ICH guidelines. Results and Conclusion: Mild degradation of the drug substance was observed during oxidative hydrolysis and considerable degradation observed during basic hydrolysis. During method validation, parameters such as precision, linearity, ruggedness, stability, robustness, and specificity were evaluated, which remained within acceptable limits. Developed UPLC method was successfully applied for evaluating assay of Ziprasidone active Pharma ingredient.

  5. The Center for Integrated Molecular Brain Imaging (Cimbi) database.

    Science.gov (United States)

    Knudsen, Gitte M; Jensen, Peter S; Erritzoe, David; Baaré, William F C; Ettrup, Anders; Fisher, Patrick M; Gillings, Nic; Hansen, Hanne D; Hansen, Lars Kai; Hasselbalch, Steen G; Henningsson, Susanne; Herth, Matthias M; Holst, Klaus K; Iversen, Pernille; Kessing, Lars V; Macoveanu, Julian; Madsen, Kathrine Skak; Mortensen, Erik L; Nielsen, Finn Årup; Paulson, Olaf B; Siebner, Hartwig R; Stenbæk, Dea S; Svarer, Claus; Jernigan, Terry L; Strother, Stephen C; Frokjaer, Vibe G

    2016-01-01

    We here describe a multimodality neuroimaging containing data from healthy volunteers and patients, acquired within the Lundbeck Foundation Center for Integrated Molecular Brain Imaging (Cimbi) in Copenhagen, Denmark. The data is of particular relevance for neurobiological research questions related to the serotonergic transmitter system with its normative data on the serotonergic subtype receptors 5-HT1A, 5-HT1B, 5-HT2A, and 5-HT4 and the 5-HT transporter (5-HTT), but can easily serve other purposes. The Cimbi database and Cimbi biobank were formally established in 2008 with the purpose to store the wealth of Cimbi-acquired data in a highly structured and standardized manner in accordance with the regulations issued by the Danish Data Protection Agency as well as to provide a quality-controlled resource for future hypothesis-generating and hypothesis-driven studies. The Cimbi database currently comprises a total of 1100 PET and 1000 structural and functional MRI scans and it holds a multitude of additional data, such as genetic and biochemical data, and scores from 17 self-reported questionnaires and from 11 neuropsychological paper/computer tests. The database associated Cimbi biobank currently contains blood and in some instances saliva samples from about 500 healthy volunteers and 300 patients with e.g., major depression, dementia, substance abuse, obesity, and impulsive aggression. Data continue to be added to the Cimbi database and biobank. PMID:25891375

  6. Association of Polymorphisms within the Serotonin Receptor Genes 5-HTR1A, 5-HTR1B, 5-HTR2A and 5-HTR2C and Migraine Susceptibility in a Turkish Population

    Science.gov (United States)

    Yücel, Yavuz; Coşkun, Salih; Cengiz, Beyhan; Özdemir, Hasan H.; Uzar, Ertuğrul; Çim, Abdullah; Camkurt, M. Akif; Aluclu, M. Ufuk

    2016-01-01

    Objective Migraine, a highly prevelant headache disorder, is regarded as a polygenic multifactorial disease. Serotonin (5-HT) and their respective receptors have been implicated in the patogenesis. Methods We investigated the 5-HT1A, 5-HT1B, 5-HT2A, and 5-HT2C receptor gene polymorphisms and their association with migraine in Turkish patients. The rs6295, rs1300060, rs1228814, rs6311, rs6313, rs6314, rs6318, rs3813929 (−759C/T) and rs518147 polymorphisms were analyzed in 135 patients with migraine and 139 healthy subjects, using a BioMark 96.96 dynamic array system. Results We found no difference in the frequency of the analyzed eight out of nine polymorpisms between migraine and control groups. However, a significant association was found between the rs3813929 polymorphism in the promoter region of 5-HTR2C gene and migraine. Also, the allele of rs3813929 was more common in the migraine group. Conclusion This result suggests that the 5-HTR2C rs3813929 polymorphism can be a genetic risk factor for migraine in a Turkish population. PMID:27489378

  7. Effects of serotonin on expression of the LDL receptor family member LR11 and 7-ketocholesterol-induced apoptosis in human vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Nagayama, Daiji; Ishihara, Noriko [Center of Diabetes, Endocrinology and Metabolism, Toho University, Sakura Medical Center, 564-1, Shimoshizu, Sakura-City, Chiba 285-8741 (Japan); Bujo, Hideaki [Department of Clinical Laboratory Medicine, Toho University, Sakura Medical Center, 564-1, Shimoshizu, Sakura-City, Chiba 285-8741 (Japan); Shirai, Kohji [Department of Vascular Function, Toho University, Sakura Medical Center, 564-1, Shimoshizu, Sakura-City, Chiba 285-8741 (Japan); Tatsuno, Ichiro, E-mail: ichiro.tatsuno@med.toho-u.ac.jp [Center of Diabetes, Endocrinology and Metabolism, Toho University, Sakura Medical Center, 564-1, Shimoshizu, Sakura-City, Chiba 285-8741 (Japan)

    2014-04-18

    Highlights: • The dedifferentiation of VSMCs in arterial intima is involved in atherosclerosis. • 5-HT showed proliferative effect on VSMCs which was abolished by sarpogrelate. • 5-HT enhanced expression of LR11 mRNA in VSMCs which was abolished by sarpogrelate. • 5-HT suppressed 7KCHO-induced apoptosis of VSMCs via caspase-3/7-dependent pathway. • The mechanisms explain the 5-HT-induced remodeling of arterial structure. - Abstract: Serotonin (5-HT) is a known mitogen for vascular smooth muscle cells (VSMCs). The dedifferentiation and proliferation/apoptosis of VSMCs in the arterial intima represent one of the atherosclerotic changes. LR11, a member of low-density lipoprotein receptor family, may contribute to the proliferation of VSMCs in neointimal hyperplasia. We conducted an in vitro study to investigate whether 5-HT is involved in LR11 expression in human VSMCs and apoptosis of VSMCs induced by 7-ketocholesterol (7KCHO), an oxysterol that destabilizes plaque. 5-HT enhanced the proliferation of VSMCs, and this effect was abolished by sarpogrelate, a selective 5-HT2A receptor antagonist. Sarpogrelate also inhibited the 5-HT-enhanced LR11 mRNA expression in VSMCs. Furthermore, 5-HT suppressed the 7KCHO-induced apoptosis of VSMCs via caspase-3/7-dependent pathway. These findings provide new insights on the changes in the differentiation stage of VSMCs mediated by 5-HT.

  8. Vasoconstrictor responses to 5-hydroxytryptamine in the autoperfused hindquarters of spontaneously hypertensive rats.

    Science.gov (United States)

    Calama, E; Morán, A; Ortiz de Urbina, A V; Martín, M L; San Román, L

    2004-06-01

    In this work we studied the responses and receptors involved in the effects of intra-arterial 5-hydroxytryptamine (5-HT) in the in situ autoperfused hindquarters of spontaneously hypertensive rats (SHR). Intra-arterial administration of the highest doses (50-1,000 ng/kg) produced a vasoconstrictor effect that was inhibited by ritanserin (a selective 5-HT2 receptor antagonist), SB 206553 (a selective 5-HT(2B/2C) receptor antagonist) and spiperone (a nonspecific 5-HT(1/2A) receptor antagonist), and was mimicked by alpha-methyl-5-HT (a selective 5-HT2 receptor agonist) and m-CPP (a selective 5-HT2C receptor agonist), but not by the intra-arterial administration of BW 723C86, a selective 5HT2B receptor agonist. SB 206553 and spiperone inhibited alpha-methyl-5HT-induced vasoconstriction in the hindquarters of SHR. Our data suggest that the vasoconstrictor response induced by 5-HT in the autoperfused hindquarters of SHR is mainly mediated by the activation of 5-HT2A and 5-HT2C receptors.

  9. Effects of serotonin on expression of the LDL receptor family member LR11 and 7-ketocholesterol-induced apoptosis in human vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Highlights: • The dedifferentiation of VSMCs in arterial intima is involved in atherosclerosis. • 5-HT showed proliferative effect on VSMCs which was abolished by sarpogrelate. • 5-HT enhanced expression of LR11 mRNA in VSMCs which was abolished by sarpogrelate. • 5-HT suppressed 7KCHO-induced apoptosis of VSMCs via caspase-3/7-dependent pathway. • The mechanisms explain the 5-HT-induced remodeling of arterial structure. - Abstract: Serotonin (5-HT) is a known mitogen for vascular smooth muscle cells (VSMCs). The dedifferentiation and proliferation/apoptosis of VSMCs in the arterial intima represent one of the atherosclerotic changes. LR11, a member of low-density lipoprotein receptor family, may contribute to the proliferation of VSMCs in neointimal hyperplasia. We conducted an in vitro study to investigate whether 5-HT is involved in LR11 expression in human VSMCs and apoptosis of VSMCs induced by 7-ketocholesterol (7KCHO), an oxysterol that destabilizes plaque. 5-HT enhanced the proliferation of VSMCs, and this effect was abolished by sarpogrelate, a selective 5-HT2A receptor antagonist. Sarpogrelate also inhibited the 5-HT-enhanced LR11 mRNA expression in VSMCs. Furthermore, 5-HT suppressed the 7KCHO-induced apoptosis of VSMCs via caspase-3/7-dependent pathway. These findings provide new insights on the changes in the differentiation stage of VSMCs mediated by 5-HT

  10. Clinical Utility of Combinatorial Pharmacogenomics-Guided Antidepressant Therapy: Evidence from Three Clinical Studies.

    Science.gov (United States)

    Altar, C Anthony; Carhart, Joseph; Allen, Josiah D; Hall-Flavin, Daniel; Winner, Joel; Dechairo, Bryan

    2015-10-01

    DNA of 258 patients with treatment-resistant depression was collected in three 8-10 week, two-arm, prospective clinical trials. Forty-four allelic variations were measured in genes for the cytochrome P450 (CYP) enzymes CYP2D6, CYPC19, and CYP1A2, the serotonin transporter (SLC6A4), and the 5-HT2A receptor (HTR2A). The combinatorial pharmacogenomic (CPGx™) GeneSight test results were provided to clinicians to support medication changes from baseline (guided arm), or they were provided at the end of each study to clinicians of unguided patients who were treated as usual (TAU). TAU subjects who at baseline were prescribed medications genetically discordant for them showed only a 12% symptom improvement, far less than the 32.5% or 28.5% improvements of the TAU subjects on yellow-category ('use with caution'; p = 0.002) or green-category medications ('use as recommended'; p = 0.02), respectively. The odds of a clinical response were increased 2.3-fold among all GeneSight-guided compared to all TAU subjects (p = 0.004), and overall, the guided group had a 53% greater improvement in depressive symptoms (p = 0.0002), a 1.7-fold relative improvement in response (p = 0.01), and a number needed to treat for one clinical response above that seen in the TAU group of 6.07. PMID:27606312

  11. Olanzapine for the prevention and treatment of chronic nausea and chemotherapy-induced nausea and vomiting.

    Science.gov (United States)

    Navari, Rudolph M

    2014-01-01

    Olanzapine is an atypical antipsychotic agent of the thiobenzodiazepine class. It blocks multiple neurotransmitter receptors including dopaminergic at D1, D2, D3, D4 brain receptors, serotonergic at 5-HT2a, 5-HT2c, 5-HT3, 5-HT6 receptors, catecholamines at alpha1 adrenergic receptors, acetylcholine at muscarinic receptors, and histamine at H1 receptors. Olanzapine has five times the affinity for 5-HT2 receptors than D2 receptors and has been used to treat schizophrenia and delirium. Olanzapine's activity at multiple receptors, particularly at the D2, 5-HT2c, and 5-HT3 receptors which appear to be involved in nausea and emesis, has prompted its use in the treatment of nausea and vomiting refractory to standard antiemetics. Case reports and formal clinical trials have demonstrated its efficacy in the treatment of chronic nausea, the prevention of chemotherapy-induced nausea and emesis, and the treatment of breakthrough chemotherapy-induced nausea and emesis. Phase II and phase III clinical trials have demonstrated that there is a significant improvement in nausea when olanzapine is added to guideline directed prophylactic antiemetic agents 5-HT3 receptor antagonists and tachykinin NK1 receptor antagonists in patients receiving moderately or highly emetogenic chemotherapy Common side effects of olanzapine when used over a period of months include weight gain as well as an association with the onset of diabetes mellitus, but these effects have not been seen with short term use of daily doses of less than one week.

  12. Average Information Content Maximization--A New Approach for Fingerprint Hybridization and Reduction.

    Directory of Open Access Journals (Sweden)

    Marek Śmieja

    Full Text Available Fingerprints, bit representations of compound chemical structure, have been widely used in cheminformatics for many years. Although fingerprints with the highest resolution display satisfactory performance in virtual screening campaigns, the presence of a relatively high number of irrelevant bits introduces noise into data and makes their application more time-consuming. In this study, we present a new method of hybrid reduced fingerprint construction, the Average Information Content Maximization algorithm (AIC-Max algorithm, which selects the most informative bits from a collection of fingerprints. This methodology, applied to the ligands of five cognate serotonin receptors (5-HT2A, 5-HT2B, 5-HT2C, 5-HT5A, 5-HT6, proved that 100 bits selected from four non-hashed fingerprints reflect almost all structural information required for a successful in silico discrimination test. A classification experiment indicated that a reduced representation is able to achieve even slightly better performance than the state-of-the-art 10-times-longer fingerprints and in a significantly shorter time.

  13. Psychosis in Parkinson's Disease: Epidemiology, Pathophysiology, and Management.

    Science.gov (United States)

    Chang, Anna; Fox, Susan H

    2016-07-01

    Psychotic symptoms are common in Parkinson's disease (PD) and are associated with poorer quality of life and increased caregiver burden. PD psychosis is correlated with several factors, such as more advanced disease, cognitive impairment, depression, and sleep disorders. The underlying causes of psychosis in PD thus involve a complex interplay between exogenous (e.g., drugs, intercurrent illnesses) and endogenous (e.g., PD disease pathology) factors. Current theories of the pathophysiology of PD psychosis have come from several neuropathological and neuroimaging studies that implicate pathways involving visual processing and executive function, including temporo-limbic structures and neocortical gray matter with altered neurotransmitter functioning (e.g., dopamine, serotonin, and acetylcholine). Treatment of PD psychosis requires a step-wise process, including initial careful investigation of treatable triggering conditions and a comprehensive evaluation with adjustment of PD medications and/or initiation of specific antipsychotic therapies. Clozapine remains the only recommended drug for the treatment of PD psychosis; however, because of regular blood monitoring, quetiapine is usually first-line therapy, although less efficacious. Emerging studies have focused on agents involving other neurotransmitters, including the serotonin 5-HT2A receptor inverse agonist pimavanserin, cholinesterase inhibitors, and antidepressants and anxiolytics.

  14. LEUPROLIDE INHIBITS MARBLE-BURYING BEHAVIOR VIA MODULATION OF 5-HT1B RECEPTOR

    Directory of Open Access Journals (Sweden)

    Parle Milind

    2011-04-01

    Full Text Available Obsessive compulsive disorder (OCD is characterized by intrusive thoughts followed by repetitive behaviors. Serotonin-related genes found in OCD include those required for coding of 5-HT transporter and 5-HT receptors (5-HT2A, 5-HT2B, 5-HT2C and 5-HT1B. Marble-burying behavior of mice is a well-accepted paradigm to screen anti-compulsive activity. The aim of this study was to evaluate the effect of leuprolide alone and it’s combination with sumatriptan or ondansetron on marble-burying behavior of mice. Leuprolide (100, 200 & 300 µg kg-1s.c. dose-dependently showed anti-compulsive effect, causing statistically significant inhibition of marble-burying behavior of mice. The prior treatment with 5HT1B/1D/1F agonist, sumatriptan (0.1 mg kg-1 s.c. potentiated the inhibitory effect of leuprolide (LHRH agonist on marble burying behavior of mice. Furthermore, prior treatment with 5HT3 antagonist, ondansetron (2 mg kg-1 s.c. did not affect the inhibitory effect of leuprolide (200 µg kg-1s.c. on marble burying behavior of mice.

  15. Neuronal correlates of visual and auditory alertness in the DMT and ketamine model of psychosis.

    Science.gov (United States)

    Daumann, J; Wagner, D; Heekeren, K; Neukirch, A; Thiel, C M; Gouzoulis-Mayfrank, E

    2010-10-01

    Deficits in attentional functions belong to the core cognitive symptoms in schizophrenic patients. Alertness is a nonselective attention component that refers to a state of general readiness that improves stimulus processing and response initiation. The main goal of the present study was to investigate cerebral correlates of alertness in the human 5HT(2A) agonist and N-methyl-D-aspartic acid (NMDA) antagonist model of psychosis. Fourteen healthy volunteers participated in a randomized double-blind, cross-over event-related functional magnetic resonance imaging (fMRI) study with dimethyltryptamine (DMT) and S-ketamine. A target detection task with cued and uncued trials in both the visual and the auditory modality was used. Administration of DMT led to decreased blood oxygenation level-dependent response during performance of an alertness task, particularly in extrastriate regions during visual alerting and in temporal regions during auditory alerting. In general, the effects for the visual modality were more pronounced. In contrast, administration of S-ketamine led to increased cortical activation in the left insula and precentral gyrus in the auditory modality. The results of the present study might deliver more insight into potential differences and overlapping pathomechanisms in schizophrenia. These conclusions must remain preliminary and should be explored by further fMRI studies with schizophrenic patients performing modality-specific alertness tasks.

  16. 25C-NBOMe: Preliminary Data on Pharmacology, Psychoactive Effects, and Toxicity of a New Potent and Dangerous Hallucinogenic Drug

    Directory of Open Access Journals (Sweden)

    Francesco Saverio Bersani

    2014-01-01

    Full Text Available Introduction. The use of novel psychoactive substances (NPSs has rapidly increased as well as their online availability. The aim of this paper is to provide a comprehensive review of the nature and the risks associated with 25C-NBOMe, which has recently appeared in the drug market. Methods. A systematic analysis of the scientific literature and a qualitative assessment of online and media resources (e.g., e-newsgroups, chat-rooms, and e-newsletters in 10 languages were carried out. Results. 25C-NBOMe is sold online as legal LSD or as research chemical with different designations such as “Boom,” “Pandora,” “Holland film,” or “N-bomb.” It is a partial agonist of 5-HT2A receptors. It is usually ingested orally/sublingually and, less commonly, nasally, through injection, vaginally, rectally, and smoked. Its effects include sublingual numbing, stimulation, “body high,” hallucinations, dissociation, and anxiety. 25C-NBOMe presents high risk of overdoses; acute toxicity and fatalities have been reported. Conclusions. 25C-NBOMe consumption represents an emerging phenomenon with potential harmful effects. Its use is increased by its online availability at low costs. Health and other professionals should be informed about this new trend of substance use.

  17. 25C-NBOMe: Preliminary Data on Pharmacology, Psychoactive Effects, and Toxicity of a New Potent and Dangerous Hallucinogenic Drug

    Science.gov (United States)

    Bersani, Francesco Saverio; Corazza, Ornella; Albano, Gabriella; Valeriani, Giuseppe; Santacroce, Rita; Bolzan Mariotti Posocco, Flaminia; Cinosi, Eduardo; Simonato, Pierluigi; Martinotti, Giovanni; Bersani, Giuseppe; Schifano, Fabrizio

    2014-01-01

    Introduction. The use of novel psychoactive substances (NPSs) has rapidly increased as well as their online availability. The aim of this paper is to provide a comprehensive review of the nature and the risks associated with 25C-NBOMe, which has recently appeared in the drug market. Methods. A systematic analysis of the scientific literature and a qualitative assessment of online and media resources (e.g., e-newsgroups, chat-rooms, and e-newsletters) in 10 languages were carried out. Results. 25C-NBOMe is sold online as legal LSD or as research chemical with different designations such as “Boom,” “Pandora,” “Holland film,” or “N-bomb.” It is a partial agonist of 5-HT2A receptors. It is usually ingested orally/sublingually and, less commonly, nasally, through injection, vaginally, rectally, and smoked. Its effects include sublingual numbing, stimulation, “body high,” hallucinations, dissociation, and anxiety. 25C-NBOMe presents high risk of overdoses; acute toxicity and fatalities have been reported. Conclusions. 25C-NBOMe consumption represents an emerging phenomenon with potential harmful effects. Its use is increased by its online availability at low costs. Health and other professionals should be informed about this new trend of substance use. PMID:25105138

  18. Effects of Ayahuasca and its Alkaloids on Drug Dependence: A Systematic Literature Review of Quantitative Studies in Animals and Humans.

    Science.gov (United States)

    Nunes, Amanda A; Dos Santos, Rafael G; Osório, Flávia L; Sanches, Rafael F; Crippa, José Alexandre S; Hallak, Jaime E C

    2016-01-01

    Recently, the anti-addictive potential of ayahuasca, a dimethyltryptamine(DMT)- and β-carboline-rich hallucinogenic beverage traditionally used by indigenous groups of the Northwest Amazon and currently by syncretic churches worldwide, has received increased attention. To better evaluate this topic, we performed a systematic literature review using the PubMed database to find quantitative studies (using statistical analysis) that assessed the effects of ayahuasca or its components in drug-related symptoms or disorders. We found five animal studies (using harmaline, harmine, or ayahuasca) and five observational studies of regular ayahuasca consumers. All animal studies showed improvement of biochemical or behavioral parameters related to drug-induced disorders. Of the five human studies, four reported significant reductions of dependence symptoms or substance use, while one did not report significant results. The mechanisms responsible for the anti-addictive properties of ayahuasca and its alkaloids are not clarified, apparently involving both peripheral MAO-A inhibition by the β-carbolines and central agonism of DMT at 5-HT2A receptors expressed in brain regions related to the regulation of mood and emotions. Although results are promising, controlled studies are needed to replicate these preliminary findings. PMID:27230395

  19. Developments in harmine pharmacology--implications for ayahuasca use and drug-dependence treatment.

    Science.gov (United States)

    Brierley, Daniel I; Davidson, Colin

    2012-12-01

    Ayahuasca is a hallucinogenic botanical mixture originating in the Amazon area where it is used ritually, but is now being taken globally. The 2 main constituents of ayahuasca are N,N-dimethyltryptamine (DMT), a hallucinogen, and harmine, a monoamine oxidase inhibitor (MAOI) which attenuates the breakdown of DMT, which would otherwise be broken down very quickly after oral consumption. Recent developments in ayahuasca use include the sale of these compounds on the internet and the substitution of related botanical (anahuasca) or synthetic (pharmahuasca) compounds to achieve the same desired hallucinogenic effects. One intriguing result of ayahuasca use appears to be improved mental health and a reduction in recidivism to alternate (alcohol, cocaine) drug use. In this review we discuss the pharmacology of ayahuasca, with a focus on harmine, and suggest pharmacological mechanisms for the putative reduction in recidivism to alcohol and cocaine misuse. These pharmacological mechanisms include MAOI, effects at 5-HT(2A) and imidazoline receptors and inhibition of dual-specificity tyrosine-phosphorylation regulated kinase 1A (DYRK1A) and the dopamine transporter. We also speculate on the therapeutic potential of harmine in other CNS conditions. PMID:22691716

  20. Endogenous psychoactive tryptamines reconsidered: an anxiolytic role for dimethyltryptamine.

    Science.gov (United States)

    Jacob, Michael S; Presti, David E

    2005-01-01

    The presence of the potent hallucinogenic psychoactive chemical N,N-dimethyltryptamine (DMT) in the human body has puzzled scientists for decades. Endogenous DMT was investigated in the 1960s and 1970s and it was proposed that DMT was involved in psychosis and schizophrenia. This hypothesis developed from comparisons of the blood and urine of schizophrenic and control subjects. However, much of this research proved inconclusive and conventional thinking has since held that trace levels of DMT, and other endogenous psychoactive tryptamines, are insignificant metabolic byproducts. The recent discovery of a G-protein-coupled, human trace amine receptor has triggered a reappraisal of the role of compounds present in limited concentrations in biological systems. Interestingly enough, DMT and other psychoactive tryptamine hallucinogens elicit a robust response at the trace amine receptor. While it is currently accepted that serotonin 5-HT(2A) receptors play a pivotal role in the activity of hallucinogenic/psychedelic compounds, we propose that the effects induced by exogenous DMT administration, especially at low doses, are due in part to activity at the trace amine receptor. Furthermore, we suggest that endogenous DMT interacts with the TA receptor to produce a calm and relaxed mental state, which may suppress, rather than promote, symptoms of psychosis. This hypothesis may help explain the inconsistency in the early analysis of endogenous DMT in humans. Finally, we propose that amphetamine action at the TA receptor may contribute to the calming effects of amphetamine and related drugs, especially at low doses. PMID:15780487

  1. Drug: D10006 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D10006 Drug Eplivanserin (USAN/INN) C19H21FN2O2 328.1587 328.3806 D10006.gif Treatm...tonin 5-HT2A-receptor [HSA:3356] [KO:K04157] Eplivanserin D10006 Eplivanserin (USAN/INN) CAS: 130579-75-8 Pu...bChem: 135626727 LigandBox: D10006 ATOM 24 1 C8x C 19.3200 -22.2600 2 C8x C 19.3200 -23.6600 3 C8x C 20.5100... -24.3600 4 C8x C 21.7700 -23.6600 5 C8y C 21.7700 -22.2600 6 C8y C 20.5100 -21.5...600 7 X F 22.9600 -21.5600 8 C2c C 20.5100 -20.1600 9 C2b C 19.3200 -19.4600 10 N2b N 21.7000 -19.4600 11 C2

  2. An evaluation of 25B-, 25C-, 25D-, 25H-, 25I- and 25T2-NBOMe via LC-MS-MS: method validation and analyte stability.

    Science.gov (United States)

    Johnson, Robert D; Botch-Jones, Sabra R; Flowers, Tiffany; Lewis, Connie A

    2014-10-01

    As potent serotonin (5-HT2A) receptor agonists, the NBOMe class of drugs including 25B-, 25C-, 25D-, 25H-, 25I- and 25T2-NBOMe is frequently abused due to the intense hallucinations that they induce. From the limited literature available, the concentration of these NBOMe compounds reported in postmortem cases is exceedingly low. In most instances, published concentrations are NBOMe, evaluation of 25B-, 25C-, 25D-, 25H and 25T2- in whole blood, plasma and urine was conducted. This publication presents the data obtained from the validation of a liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of these six NBOMe analogs. The method utilizes ultra-performance liquid chromatography technology for the separation followed by positive electrospray ionization of each analog. Limits of quantification for these analogs ranged from 0.01 to 0.02 ng/mL (10-20 pg/mL) with typical linear dynamic ranges of 0.01-20 ng/mL. Data for recovery, intraday control accuracy and precision, matrix effects, ion suppression/enhancement and analyte stability are included. Validation was completed in whole blood, plasma and urine. Short run times and high sensitivity afforded by this newly validated analytical method that allows for the detection of these six analogs in the most common toxicological matrices and can be applied to both ante- and postmortem specimens.

  3. The NBOMe hallucinogenic drug series: Patterns of use, characteristics of users and self-reported effects in a large international sample.

    Science.gov (United States)

    Lawn, Will; Barratt, Monica; Williams, Martin; Horne, Abi; Winstock, Adam

    2014-08-01

    The NBOMe compounds are a novel series of hallucinogenic drugs that are potent agonists of the 5-HT2A receptor, have a short history of human consumption and are available to buy online, in most countries. In this study, we sought to investigate the patterns of use, characteristics of users and self-reported effects. A cross-sectional anonymous online survey exploring the patterns of drug use was conducted in 2012 (n = 22,289), including questions about the use of 25B-NBOMe, 25C-NBOMe, and 25I-NBOMe and comparison drugs. We found that 2.6% of respondents (n = 582) reported having ever tried one of the three NBOMe drugs and that at 2.0%, 25I-NBOMe was the most popular (n = 442). Almost all (93.5%) respondents whose last new drug tried was a NBOMe drug, tried it in 2012, and 81.2% of this group administered the drug orally or sublingually/buccally. Subjective effects were similar to comparison serotonergic hallucinogens, though higher 'negative effects while high' and greater 'value for money' were reported. The most common (41.7%) drug source was via a website. The NBOMe drugs have emerged recently, are frequently bought using the internet and have similar effects to other hallucinogenic drugs; however, they may pose larger risks, due to the limited knowledge about them, their relatively low price and availability via the internet.

  4. High-performance liquid chromatography with tandem mass spectrometry for the determination of nine hallucinogenic 25-NBOMe designer drugs in urine specimens.

    Science.gov (United States)

    Poklis, Justin L; Clay, Deborah J; Poklis, Alphonse

    2014-04-01

    We present a high-performance liquid chromatography triple quadrupole mass spectrometry (HPLC-MS-MS) method for the identification and quantification of nine serotonin 5-HT2A receptor agonist hallucinogenic substances from a new class of N-methoxybenzyl derivatives of methoxyphenylethylamine (NBOMe) designer drugs in human urine: 25H-NBOMe, 2CC-NBOMe, 25I-NBF, 25D-NBOMe, 25B-NBOMe, 2CT-NBOMe, 25I-NBMD, 25G-NBOMe and 25I-NBOMe. This assay was developed for the Virginia Commonwealth University Clinical and Forensic Toxicology laboratory to screen emergency department specimens in response to an outbreak of N-benzyl-phenethylamine derivative abuse and overdose cases in Virginia. The NBOMe derivatives were rapidly extracted from the urine specimens by use of FASt™ solid-phase extraction columns. Assay performance was determined as recommended for validation by the Scientific Working Group for Forensic Toxicology (SWGTOX) for linearity, lower limit of quantification, lower limit of detection, accuracy/bias, precision, dilution integrity, carryover, selectivity, absolute recovery, ion suppression and stability. Linearity was verified to be from 1 to 100 ng/mL for each of the nine analytes. The bias determined for the NBOMe derivatives was 86-116% with a NBOMe derivatives were detected using the presented method in patient urine specimens.

  5. Analysis of 25I-NBOMe, 25B-NBOMe, 25C-NBOMe and Other Dimethoxyphenyl-N-[(2-Methoxyphenyl) Methyl]Ethanamine Derivatives on Blotter Paper.

    Science.gov (United States)

    Poklis, Justin L; Raso, Stephen A; Alford, Kylie N; Poklis, Alphonse; Peace, Michelle R

    2015-10-01

    In recent years, N-methoxybenzyl-methoxyphenylethylamine (NBOMe) derivatives, a class of designer hallucinogenic drugs, have become popular drugs of abuse. These drugs have been the cause of severe intoxications and even deaths. They act as 5-HT2A receptors agonists and have been reported to produce serotonin-like syndrome with bizarre behavior, severe agitation and seizures persisting for as long as 3 days. The most commonly reported derivatives are 25I-NBOMe, 25B-NBOMe and 25C-NBOMe, respectively 2-(4-iodo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl) methyl]ethanamine, N-(2-methoxybenzyl)-2,5-dimethoxy-4-bromophenethylamine and N-(2-methoxybenzyl)-2,5-dimethoxy-4-chlorophenethylamine. Like many low dose hallucinogenic drugs these compounds are often sold on blotter paper. Three different types of commercially available blotter papers reported to contain NBOMe derivatives were obtained. These blotter papers were screened using Direct Analysis in Real Time AccuTOF(TM) mass spectrometry followed by confirmation and quantification by high-performance liquid chromatography triple quadrapole mass spectrometry. The major drug present on each of the three blotter products was different, 25I-NBOMe, 25C-NBOMe or 25B-NBOMe. The blotter papers were also found to have minute amounts of two or three NBOMe derivative impurities of 25H-NBOMe, 25I-NBOMe, 25C-NBOMe, 25B-NBOMe and/or 25D-NBOMe.

  6. 25I-NBOMe related death in Australia: a case report.

    Science.gov (United States)

    Kueppers, Victoria B; Cooke, Clive T

    2015-04-01

    We present a toxicologically confirmed 25I-NBOMe related death from Australia. 25I-NBOMe is a synthetic new psychoactive substance (NPS), which is a derivative of the 2C-X series of phenethylamines. NBOMe compounds have hallucinogenic and stimulant properties and are potent agonists of the human 5HT2A receptor. They have been associated with severe toxicity and fatalities. No case reports on deaths related to 25I-NBOMe toxicity from Australia have been published thus far. Very limited toxicological data is available in the current literature. The decedent in the presented case had a post mortem aortic non-preserved blood concentration of 25I-NBOMe of approximately 28 μg/L, a concentration that appears to be much higher than those previously reported in non-fatal cases of toxicity and analytically confirmed 25I-NBOMe related fatalities. The publication of new data is essential in improving knowledge and awareness amongst the forensic community regarding emerging psychoactive substances, such as the NBOMe compounds.

  7. Analysis of 25I-NBOMe, 25B-NBOMe, 25C-NBOMe and Other Dimethoxyphenyl-N-[(2-Methoxyphenyl) Methyl]Ethanamine Derivatives on Blotter Paper

    Science.gov (United States)

    Poklis, Justin L.; Raso, Stephen A.; Alford, Kylie N.; Poklis, Alphonse; Peace, Michelle R.

    2015-01-01

    In recent years, N-methoxybenzyl-methoxyphenylethylamine (NBOMe) derivatives, a class of designer hallucinogenic drugs, have become popular drugs of abuse. These drugs have been the cause of severe intoxications and even deaths. They act as 5-HT2A receptors agonists and have been reported to produce serotonin-like syndrome with bizarre behavior, severe agitation and seizures persisting for as long as 3 days. The most commonly reported derivatives are 25I-NBOMe, 25B-NBOMe and 25C-NBOMe, respectively 2-(4-iodo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl) methyl]ethanamine, N-(2-methoxybenzyl)-2,5-dimethoxy-4-bromophenethylamine and N-(2-methoxybenzyl)-2,5-dimethoxy-4-chlorophenethylamine. Like many low dose hallucinogenic drugs these compounds are often sold on blotter paper. Three different types of commercially available blotter papers reported to contain NBOMe derivatives were obtained. These blotter papers were screened using Direct Analysis in Real Time AccuTOFTM mass spectrometry followed by confirmation and quantification by high-performance liquid chromatography triple quadrapole mass spectrometry. The major drug present on each of the three blotter products was different, 25I-NBOMe, 25C-NBOMe or 25B-NBOMe. The blotter papers were also found to have minute amounts of two or three NBOMe derivative impurities of 25H-NBOMe, 25I-NBOMe, 25C-NBOMe, 25B-NBOMe and/or 25D-NBOMe. PMID:26378135

  8. High-Performance Liquid Chromatography with Tandem Mass Spectrometry for the Determination of Nine Hallucinogenic 25-NBOMe Designer Drugs in Urine Specimens

    Science.gov (United States)

    Poklis, Justin L.; Clay, Deborah J.; Poklis, Alphonse

    2014-01-01

    We present a high-performance liquid chromatography triple quadrupole mass spectrometry (HPLC–MS-MS) method for the identification and quantification of nine serotonin 5-HT2A receptor agonist hallucinogenic substances from a new class of N-methoxybenzyl derivatives of methoxyphenylethylamine (NBOMe) designer drugs in human urine: 25H-NBOMe, 2CC-NBOMe, 25I-NBF, 25D-NBOMe, 25B-NBOMe, 2CT-NBOMe, 25I-NBMD, 25G-NBOMe and 25I-NBOMe. This assay was developed for the Virginia Commonwealth University Clinical and Forensic Toxicology laboratory to screen emergency department specimens in response to an outbreak of N-benzyl-phenethylamine derivative abuse and overdose cases in Virginia. The NBOMe derivatives were rapidly extracted from the urine specimens by use of FASt™ solid-phase extraction columns. Assay performance was determined as recommended for validation by the Scientific Working Group for Forensic Toxicology (SWGTOX) for linearity, lower limit of quantification, lower limit of detection, accuracy/bias, precision, dilution integrity, carryover, selectivity, absolute recovery, ion suppression and stability. Linearity was verified to be from 1 to 100 ng/mL for each of the nine analytes. The bias determined for the NBOMe derivatives was 86–116% with a NBOMe derivatives were detected using the presented method in patient urine specimens. PMID:24535338

  9. Derivatives of Ergot-alkaloids: Molecular structure, physical properties, and structure-activity relationships

    Science.gov (United States)

    Ivanova, Bojidarka B.; Spiteller, Michael

    2012-09-01

    A comprehensive screening of fifteen functionalized Ergot-alkaloids, containing bulk aliphatic cyclic substituents at D-ring of the ergoline molecular skeleton was performed, studying their structure-active relationships and model interactions with α2A-adreno-, serotonin (5HT2A) and dopamine D3 (D3A) receptors. The accounted high affinity to the receptors binding loops and unusual bonding situations, joined with the molecular flexibility of the substituents and the presence of proton accepting/donating functional groups in the studied alkaloids, may contribute to further understanding the mechanisms of biological activity in vivo and in predicting their therapeutic potential in central nervous system (CNS), including those related the Schizophrenia. Since the presented correlation between the molecular structure and properties, was based on the comprehensively theoretical computational and experimental physical study on the successfully isolated derivatives, through using routine synthetic pathways in a relatively high yields, marked these derivatives as 'treasure' for further experimental and theoretical studied in areas such as: (a) pharmacological and clinical testing; (b) molecular-drugs design of novel psychoactive substances; (c) development of the analytical protocols for determination of Ergot-alkaloids through a functionalization of the ergoline-skeleton, and more.

  10. Test-retest paradigm of the forced swimming test in female mice is not valid for predicting antidepressant-like activity: participation of acetylcholine and sigma-1 receptors.

    Science.gov (United States)

    Su, Jing; Hato-Yamada, Noriko; Araki, Hiroaki; Yoshimura, Hiroyuki

    2013-01-01

    The forced swimming test (FST) in mice is widely used to predict the antidepressant activity of a drug, but information describing the immobility of female mice is limited. We investigated whether a prior swimming experience affects the immobility duration in a second FST in female mice and whether the test-retest paradigm is a valid screening tool for antidepressants. Female ICR mice were exposed to the FST using two experimental paradigms: a single FST and a double FST in which mice had experienced FST once 24 h prior to the second trail. The initial FST experience reliably prolonged immobility duration in the second FST. The antidepressants imipramine and paroxetine significantly reduced immobility duration in the single FST, but not in the double FST. Scopolamine and the sigma-1 (σ1) antagonist NE-100 administered before the second trial significantly prevented the prolongation of immobility. Neither a 5-HT1A nor a 5-HT2A receptor agonist affected immobility duration. We suggest that the test-retest paradigm in female mice is not adequate for predicting antidepressant-like activity of a drug; the prolongation of immobility in the double FST is modulated through acetylcholine and σ1 receptors.

  11. Gene expression profiling in the human middle cerebral artery after cerebral ischemia.

    Science.gov (United States)

    Vikman, P; Edvinsson, L

    2006-12-01

    We have investigated the gene expression in human middle cerebral artery (MCA) after ischemia. Ischemic stroke affects the perfusion in the affected area and experimental cerebral ischemia results in upregulation of vasopressor receptors in the MCA leading to the ischemic area. We obtained human MCA samples distributing to the ischemic area, 7-10 days post-stroke. The gene expression was examined with real-time polymerase chain reaction (PCR) and microarray, proteins were studied with immunohistochemistry. We investigated genes previously shown to be upregulated in animal models of cerebral ischemia (e.g. ET(A), ET(B), AT1, AT2, and 5-HT(2A/1B/1D)). Their mRNA expression was increased compared with controls, consistent with findings in experimental stroke. Immunohistochemistry showed upregulation of the receptors localized on the smooth muscle cells. The gene expression was profiled with microarray and seven genes chosen for further investigation with real-time PCR; ELK3, LY64, Metallothionin IG, POU3F4, Actin alpha2, RhoA and smoothelin. Six of these were regulated the same way when confirming array expression with real-time PCR. Gene expression studies in the human MCA leading to the ischemic region is similar to that seen after MCA occlusion in rats. We found new genes that support the dynamic changes that occur in the MCA distributing to the ischemic region. PMID:17116215

  12. Cariprazine:New dopamine biased agonist for neuropsychiatric disorders.

    Science.gov (United States)

    De Deurwaerdère, P

    2016-02-01

    Cariprazine (RGH-188, MP-214, Vraylar[TM]) is a new dopamine receptor ligand developed for the treatment of several neuropsychiatric diseases including schizophrenia and bipolar disorders. Cariprazine displays higher affinity at dopamine D3 receptors and a similar affinity at D2 and 5-HT2B receptors. At variance with some atypical antipsychotics, its affinity at 5-HT1A, 5-HT2A and histamine H1 receptors is modest compared with its three main targets. Cariprazine could correspond to a biased agonist at dopamine receptors, displaying either antagonist or partial agonist properties depending on the signaling pathways linked to D2/D3 receptors. The compound crosses the blood-brain barrier, as revealed by positron emission tomography and pharmacokinetic studies in various species. Two main metabolites result mainly from the activity of CYP34A and display properties similar to those of the parent drug. Behavioral data report that cariprazine is efficacious in animal models addressing positive, negative and cognitive symptoms of schizophrenia with no extrapyramidal side effects. In September 2015, the FDA approved the use of cariprazine for the treatment of schizophrenia and type I bipolar disorder. The efficacy of cariprazine in other neuropsychiatric diseases is currently being evaluated in preclinical and clinical studies. Side effects have been observed in humans, including extrapyramidal side effects and akathisia of mild to moderate intensity. PMID:27092339

  13. Serotonin alterations in anorexia and bulimia nervosa: new insights from imaging studies.

    Science.gov (United States)

    Kaye, Walter H; Frank, Guido K; Bailer, Ursula F; Henry, Shannan E; Meltzer, Carolyn C; Price, Julie C; Mathis, Chester A; Wagner, Angela

    2005-05-19

    Anorexia nervosa (AN) and bulimia nervosa (BN) are related disorders with relatively homogenous presentations such as age of onset and gender distribution. In addition, they share symptoms, such as extremes of food consumption, body image distortion, anxiety and obsessions, and ego-syntonic neglect, raises the possibility that these symptoms reflect disturbed brain function that contributes to the pathophysiology of this illness. Recent brain imaging studies have identified altered activity in frontal, cingulate, temporal, and parietal cortical regions in AN and BN. Importantly, such disturbances are present when subjects are ill and persist after recovery, suggesting that these may be traits that are independent of the state of the illness. Emerging data point to a dysregulation of serotonin pathways in cortical and limbic structures that may be related to anxiety, behavioral inhibition, and body image distortions. In specific, recent studies using PET with serotonin specific radioligands implicate alterations of 5-HT1A and 5-HT2A receptors and the 5-HT transporter. Alterations of these circuits may affect mood and impulse control as well as the motivating and hedonic aspects of feeding behavior. Such imaging studies may offer insights into new pharmacology and psychotherapy approaches.

  14. The developmental basis of epigenetic regulation of HTR2A and psychiatric outcomes.

    Science.gov (United States)

    Paquette, Alison G; Marsit, Carmen J

    2014-12-01

    The serotonin receptor 5-HT2A (encoded by HTR2A) is an important regulator of fetal brain development and adult cognitive function. Environmental signals that induce epigenetic changes of serotonin response genes, including HTR2A, have been implicated in adverse mental health outcomes. The objective of this perspective article is to address the medical implications of HTR2A epigenetic regulation, which has been associated with both infant neurobehavioral outcomes and adult mental health. Ongoing research has identified a region of the HTR2A promoter that has been associated with a number of medical outcomes in adults and infants, including bipolar disorder, schizophrenia, chronic fatigue syndrome, borderline personality disorder, suicidality, and neurobehavioral outcomes. Epigenetic regulation of HTR2A has been studied in several different types of tissues, including the placenta. The placenta is an important source of serotonin during fetal neurodevelopment, and placental epigenetic variation of HTR2A has been associated with infant neurobehavioral outcomes, which may represent the basis of adult mental health disorders. Further analysis is needed to identify intrinsic and extrinsic factors that modulate HTR2A methylation, and the mechanism by which this epigenetic variation influences fetal growth and leads to altered brain development, manifesting in psychiatric disorders.

  15. Linoleic acid derivative DCP-LA ameliorates stress-induced depression-related behavior by promoting cell surface 5-HT1A receptor translocation, stimulating serotonin release, and inactivating GSK-3β.

    Science.gov (United States)

    Kanno, Takeshi; Tanaka, Akito; Nishizaki, Tomoyuki

    2015-04-01

    Impairment of serotonergic neurotransmission is the major factor responsible for depression and glycogen synthase kinase 3β (GSK-3β) participates in serotonergic transmission-mediated signaling networks relevant to mental illnesses. In the forced-swim test to assess depression-like behavior, the immobility time for mice with restraint stress was significantly longer than that for nonstressed control mice. Postsynaptic cell surface localization of 5-HT1A receptor, but not 5-HT2A receptor, in the hypothalamus for mice with restraint stress was significantly reduced as compared with that for control mice, which highly correlated to prolonged immobility time, i.e., depression-like behavior. The linoleic acid derivative 8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid (DCP-LA) restored restraint stress-induced reduction of cell surface 5-HT1A receptor and improved depression-like behavior in mice with restraint stress. Moreover, DCP-LA stimulated serotonin release from hypothalamic slices and cancelled restraint stress-induced reduction of GSK-3β phosphorylation at Ser9. Taken together, the results of the present study indicate that DCP-LA could ameliorate depression-like behavior by promoting translocation of 5-HT1A receptor to the plasma membrane on postsynaptic cells, stimulating serotonin release, and inactivating GSK-3β.

  16. 5-HT2B Receptor Antagonists Inhibit Fibrosis and Protect from RV Heart Failure

    Directory of Open Access Journals (Sweden)

    Wiebke Janssen

    2015-01-01

    Full Text Available Objective. The serotonin (5-HT pathway was shown to play a role in pulmonary hypertension (PH, but its functions in right ventricular failure (RVF remain poorly understood. The aim of the current study was to investigate the effects of Terguride (5-HT2A and 2B receptor antagonist or SB204741 (5-HT2B receptor antagonist on right heart function and structure upon pulmonary artery banding (PAB in mice. Methods. Seven days after PAB, mice were treated for 14 days with Terguride (0.2 mg/kg bid or SB204741 (5 mg/kg day. Right heart function and remodeling were assessed by right heart catheterization, magnetic resonance imaging (MRI, and histomorphometric methods. Total secreted collagen content was determined in mouse cardiac fibroblasts isolated from RV tissues. Results. Chronic treatment with Terguride or SB204741 reduced right ventricular fibrosis and showed improved heart function in mice after PAB. Moreover, 5-HT2B receptor antagonists diminished TGF-beta1 induced collagen synthesis of RV cardiac fibroblasts in vitro. Conclusion. 5-HT2B receptor antagonists reduce collagen deposition, thereby inhibiting right ventricular fibrosis. Chronic treatment prevented the development and progression of pressure overload-induced RVF in mice. Thus, 5-HT2B receptor antagonists represent a valuable novel therapeutic approach for RVF.

  17. Neuroimaging in eating disorders

    Directory of Open Access Journals (Sweden)

    Jáuregui-Lobera I

    2011-09-01

    Full Text Available Ignacio Jáuregui-LoberaBehavioral Sciences Institute and Pablo de Olavide University, Seville, SpainAbstract: Neuroimaging techniques have been useful tools for accurate investigation of brain structure and function in eating disorders. Computed tomography, magnetic resonance imaging, positron emission tomography, single photon emission computed tomography, magnetic resonance spectroscopy, and voxel-based morphometry have been the most relevant technologies in this regard. The purpose of this review is to update the existing data on neuroimaging in eating disorders. The main brain changes seem to be reversible to some extent after adequate weight restoration. Brain changes in bulimia nervosa seem to be less pronounced than in anorexia nervosa and are mainly due to chronic dietary restrictions. Different subtypes of eating disorders might be correlated with specific brain functional changes. Moreover, anorectic patients who binge/purge may have different functional brain changes compared with those who do not binge/purge. Functional changes in the brain might have prognostic value, and different changes with respect to the binding potential of 5-HT1A, 5-HT2A, and D2/D3 receptors may be persistent after recovering from an eating disorder.Keywords: neuroimaging, brain changes, brain receptors, anorexia nervosa, bulimia nervosa, eating disorders

  18. ITI-007 in the treatment of schizophrenia: from novel pharmacology to clinical outcomes.

    Science.gov (United States)

    Davis, Robert E; Correll, Christoph U

    2016-06-01

    ITI-007 is an investigational drug being developed for schizophrenia and other neuropsychiatric/neurodegenerative diseases. ITI-007 has a unique pharmacological profile, combining potent 5-HT2a receptor antagonism with cell-type-specific dopamine and glutamate receptor modulation, plus serotonin reuptake inhibition. At dopamine-D2 receptors, ITI-007 acts as a post-synaptic antagonist and pre-synaptic partial agonist. Additionally, ITI-007 stimulates phosphorylation of glutamatergic NMDA-NR2B receptors, downstream of dopamine-D1 receptor intracellular signaling. Based on a large, placebo and risperidone controlled, Phase-II trial, ITI-007 60 mg was shown to be effective in reducing symptoms in patients with acutely exacerbated schizophrenia. The antipsychotic efficacy of ITI-007 60 mg in this patient population was confirmed in a recently completed Phase III study. ITI-007 was associated with minimal safety risk compared to risperidone (Phase II study) or placebo (both studies) for neuromotor disturbances, prolactin changes, weight gain and metabolic abnormalities. A second 6-week, placebo and risperidone-controlled Phase-III trial in acutely exacerbated schizophrenia is ongoing. PMID:27042868

  19. The clinical utility of lurasidone in schizophrenia: patient considerations

    Directory of Open Access Journals (Sweden)

    Harvey PD

    2015-04-01

    Full Text Available Philip D Harvey1Department of Psychiatry and Behavioral Sciences, University of Miami, Miller School of Medicine, Miami, FL, USA; 2Bruce W Carter VA Medical Center, Miami, FL, USAAbstract: Lurasidone is a novel antipsychotic agent approved for the treatment of schizophrenia in a number of countries including the United Kingdom, other European countries, the United States, and Canada. In addition to full antagonist activity at the dopamine D2 (Ki, 1 nM and serotonin 5-HT2A (Ki, 0.5 nM receptors, the pharmacodynamic profile of lurasidone is notable for its high affinity for serotonin 5-HT7 receptors (0.5 nM and its partial agonist activity at 5-HT1A receptors (Ki, 6.4 nM. Long-term treatment of schizophrenia with lurasidone has been shown to reduce the risk of relapse in patients with schizophrenia. Lurasidone appears to be associated with minimal effects on body weight, and low risk for clinically meaningful alterations in glucose, lipids, or electrocardiography parameters. Evidence from two randomized trials also suggests improvement in functional capacity and cognitive functioning in people with schizophrenia. A significant evidence base supports the use of lurasidone as a promising agent for the treatment of schizophrenia. Keywords: long-term treatment, antagonist, pharmacodynamic profile

  20. Average Information Content Maximization—A New Approach for Fingerprint Hybridization and Reduction

    Science.gov (United States)

    Śmieja, Marek; Warszycki, Dawid

    2016-01-01

    Fingerprints, bit representations of compound chemical structure, have been widely used in cheminformatics for many years. Although fingerprints with the highest resolution display satisfactory performance in virtual screening campaigns, the presence of a relatively high number of irrelevant bits introduces noise into data and makes their application more time-consuming. In this study, we present a new method of hybrid reduced fingerprint construction, the Average Information Content Maximization algorithm (AIC-Max algorithm), which selects the most informative bits from a collection of fingerprints. This methodology, applied to the ligands of five cognate serotonin receptors (5-HT2A, 5-HT2B, 5-HT2C, 5-HT5A, 5-HT6), proved that 100 bits selected from four non-hashed fingerprints reflect almost all structural information required for a successful in silico discrimination test. A classification experiment indicated that a reduced representation is able to achieve even slightly better performance than the state-of-the-art 10-times-longer fingerprints and in a significantly shorter time. PMID:26784447

  1. Using psilocybin to investigate the relationship between attention, working memory, and the serotonin 1A and 2A receptors.

    Science.gov (United States)

    Carter, Olivia L; Burr, David C; Pettigrew, John D; Wallis, Guy M; Hasler, Felix; Vollenweider, Franz X

    2005-10-01

    Increasing evidence suggests a link between attention, working memory, serotonin (5-HT), and prefrontal cortex activity. In an attempt to tease out the relationship between these elements, this study tested the effects of the hallucinogenic mixed 5-HT1A/2A receptor agonist psilocybin alone and after pretreatment with the 5-HT2A antagonist ketanserin. Eight healthy human volunteers were tested on a multiple-object tracking task and spatial working memory task under the four conditions: placebo, psilocybin (215 microg/kg), ketanserin (50 mg), and psilocybin and ketanserin. Psilocybin significantly reduced attentional tracking ability, but had no significant effect on spatial working memory, suggesting a functional dissociation between the two tasks. Pretreatment with ketanserin did not attenuate the effect of psilocybin on attentional performance, suggesting a primary involvement of the 5-HT1A receptor in the observed deficit. Based on physiological and pharmacological data, we speculate that this impaired attentional performance may reflect a reduced ability to suppress or ignore distracting stimuli rather than reduced attentional capacity. The clinical relevance of these results is also discussed.

  2. Advances in synthesis of pimavanserin%哌马色林的合成研究进展

    Institute of Scientific and Technical Information of China (English)

    甘润; 胡湘南

    2016-01-01

    Pimavanserin(Nuplazid) is a drug of selective targeting 5-HT2A receptor,developed by Acadia Pharmaceuticals. In April 29,2016,it was approved by FDA for the treatment of Parkinson′s disease(PD)patients experiencing mental symptoms such as hallucinations and delusions. In this paper,we summarize the synthetic methods of pimavanserin published in literature in re⁃cent years and their advantages and disadvantages.%哌马色林(匹莫范色林,pimavanserin,Nuplazid)是选择性靶向5-HT2A受体药,由美国Acadia Pharmaceuticals公司研制,2016年4月29日获FDA批准用于治疗帕金森病(PD)患者所经历幻觉和妄想等精神症状。本文综述了近年来文献报道的该药合成方法,并对其优缺点进行评述。

  3. Serotonin 5-HT2 receptor interactions with dopamine function: implications for therapeutics in cocaine use disorder.

    Science.gov (United States)

    Howell, Leonard L; Cunningham, Kathryn A

    2015-01-01

    Cocaine exhibits prominent abuse liability, and chronic abuse can result in cocaine use disorder with significant morbidity. Major advances have been made in delineating neurobiological mechanisms of cocaine abuse; however, effective medications to treat cocaine use disorder remain to be discovered. The present review will focus on the role of serotonin (5-HT; 5-hydroxytryptamine) neurotransmission in the neuropharmacology of cocaine and related abused stimulants. Extensive research suggests that the primary contribution of 5-HT to cocaine addiction is a consequence of interactions with dopamine (DA) neurotransmission. The literature on the neurobiological and behavioral effects of cocaine is well developed, so the focus of the review will be on cocaine with inferences made about other monoamine uptake inhibitors and releasers based on mechanistic considerations. 5-HT receptors are widely expressed throughout the brain, and several different 5-HT receptor subtypes have been implicated in mediating the effects of endogenous 5-HT on DA. However, the 5-HT2A and 5-HT2C receptors in particular have been implicated as likely candidates for mediating the influence of 5-HT in cocaine abuse as well as to traits (e.g., impulsivity) that contribute to the development of cocaine use disorder and relapse in humans. Lastly, new approaches are proposed to guide targeted development of serotonergic ligands for the treatment of cocaine use disorder. PMID:25505168

  4. Serotonin signaling mediates protein valuation and aging.

    Science.gov (United States)

    Ro, Jennifer; Pak, Gloria; Malec, Paige A; Lyu, Yang; Allison, David B; Kennedy, Robert T; Pletcher, Scott D

    2016-01-01

    Research into how protein restriction improves organismal health and lengthens lifespan has largely focused on cell-autonomous processes. In certain instances, however, nutrient effects on lifespan are independent of consumption, leading us to test the hypothesis that central, cell non-autonomous processes are important protein restriction regulators. We characterized a transient feeding preference for dietary protein after modest starvation in the fruit fly, Drosophila melanogaster, and identified tryptophan hydroxylase (Trh), serotonin receptor 2a (5HT2a), and the solute carrier 7-family amino acid transporter, JhI-21, as required for this preference through their role in establishing protein value. Disruption of any one of these genes increased lifespan up to 90% independent of food intake suggesting the perceived value of dietary protein is a critical determinant of its effect on lifespan. Evolutionarily conserved neuromodulatory systems that define neural states of nutrient demand and reward are therefore sufficient to control aging and physiology independent of food consumption. PMID:27572262

  5. Ritanserin-sensitive receptors modulate the prosocial and the anxiolytic effect of MDMA derivatives, DOB and PMA, in zebrafish.

    Science.gov (United States)

    Ponzoni, Luisa; Sala, Mariaelvina; Braida, Daniela

    2016-11-01

    Little is known about the pharmacological effects of amphetamine derivatives. In the present study, the effect on social preference and anxiety-like behavior of 2,5-dimetoxy-4-bromo-amphetamine hydrobromide (DOB) and para-methoxyamphetamine (PMA), in comparison with 3,4 methylenedioxymethamphetamine (MDMA) was investigated in zebrafish, an emerging model to study emotional behavior in an inexpensive and quick manner. DOB (0.05-2mg/kg), PMA (0.0005-2mg/kg) or MDMA (0.25-20mg/kg), given i.m. to adult zebrafish, progressively increased the time spent in the proximity of nacre fish picture in a social preference test. However, high doses were ineffective. Similarly, in the novel tank diving and light-dark tests the compounds elicited a progressive anxiolytic effect in terms of time spent in the upper half of the tank and in the light compartment, respectively. All the above effects were interpolated by symmetrical parabolas. The 5-HT2A/C antagonist ritanserin (0.025-2.5mg/kg) in association with the maximal effective dose of MDMA, DOB and PMA blocked both the social and anxiolytic effect. Taken together these findings demonstrate for the first time the prosocial and anxiolytic properties of DOB and PMA and focus on the mechanisms of their action through the serotonergic-like system suggesting a potential clinical application. PMID:27506653

  6. Contractile effects of 3,4-methylenedioxymethamphetamine on the human internal mammary artery.

    Science.gov (United States)

    Silva, Sónia; Carvalho, Félix; Fernandes, Eduarda; Antunes, Manuel J; Cotrim, Maria Dulce

    2016-08-01

    Since the late 1980s numerous reports have detailed adverse reactions to the use of 3,4-methylenedioxymethamphetamine (MDMA) associated with cardiovascular collapse and sudden death, following ventricular tachycardia and hypertension. For a better understanding of the effects of MDMA on the cardiovascular system, it is critical to determine their effects at the vasculature level, including the transporter or neurotransmitter systems that are most affected at the whole range of drug doses. With this purpose in mind, the aim of our study was to evaluate the contractile effect of MDMA in the human internal mammary artery, the contribution of SERT for this effect and the responsiveness of this artery to 5-HT in the presence of MDMA. We have also studied the possible involvement of 5-HT2 receptors on the MDMA contractile effect in this human blood vessel using ketanserin. Our results showed that MDMA contracted the studied human's internal mammary artery in a SERT-independent form, through activation of 5-HT2A receptors. Considering the high plasma concentrations achieved in heavy users or in situations of acute exposure to drugs, this effect is probably involved in the cardiovascular risk profile of this psychostimulant, especially in subjects with pre-existing cardiovascular disease. PMID:27079619

  7. 18β-Glycyrrhetinic Acid, a Novel Naturally Derived Agent, Suppresses Prolactin Hyperactivity and Reduces Antipsychotic-Induced Hyperprolactinemia in In Vitro and In Vivo Models.

    Science.gov (United States)

    Wang, Di; Zhang, Yongfeng; Wang, Chunyue; Jia, Dongxu; Cai, Guangsheng; Lu, Jiahui; Wang, Di; Zhang, Zhang-Jin

    2016-09-01

    The purpose of this study was to examine the effects of 18β-glycyrrhetinic acid (GA), a novel naturally derived agent, in suppressing prolactin (PRL) hyperactivity and reducing antipsychotic-induced hyperprolactinemia (hyperPRL) and the underlying mechanisms in in vitro and in vivo models. GA treatment for 24 h inhibited PRL synthesis and secretion in MMQ cells and cultured pituitary cells in a dose-dependent fashion; but this effect was not reproduced in GH3 cells that lack the expression of functional dopamine D2 receptors. GA suppressed elevated PRL level and growth hormone, and normalized several sex hormones in a rat model of hyperPRL, produced by repeated injection of the dopamine blocker metoclopramide. GA also modulated the expression 5-HT1A and 5-HT2A receptors in both in vivo and in vitro models. These results indicate that GA is effective in suppressing PRL hyperactivity caused by the blockade of dopamine D2 receptors. This suppressive effect of GA may be related to its modulation of the serotonergic system. This study provides additional evidence in support of GA as an adjunct for the treatment of hyperPRL.

  8. To Cheat or Not To Cheat: Tryptophan Hydroxylase 2 SNP Variants Contribute to Dishonest Behavior.

    Science.gov (United States)

    Shen, Qiang; Teo, Meijun; Winter, Eyal; Hart, Einav; Chew, Soo H; Ebstein, Richard P

    2016-01-01

    Although, lying (bear false witness) is explicitly prohibited in the Decalogue and a focus of interest in philosophy and theology, more recently the behavioral and neural mechanisms of deception are gaining increasing attention from diverse fields especially economics, psychology, and neuroscience. Despite the considerable role of heredity in explaining individual differences in deceptive behavior, few studies have investigated which specific genes contribute to the heterogeneity of lying behavior across individuals. Also, little is known concerning which specific neurotransmitter pathways underlie deception. Toward addressing these two key questions, we implemented a neurogenetic strategy and modeled deception by an incentivized die-under-cup task in a laboratory setting. The results of this exploratory study provide provisional evidence that SNP variants across the tryptophan hydroxylase 2 (TPH2) gene, that encodes the rate-limiting enzyme in the biosynthesis of brain serotonin, contribute to individual differences in deceptive behavior. PMID:27199691

  9. To cheat or not to cheat: Tryptophan hydroxylase 2 SNP variants contribute to dishonest behavior

    Directory of Open Access Journals (Sweden)

    Qiang eShen

    2016-05-01

    Full Text Available Although lying (bear false witness is explicitly prohibited in the Decalogue and a focus of interest in philosophy and theology, more recently the behavioral and neural mechanisms of deception are gaining increasing attention from diverse fields especially economics, psychology and neuroscience. Despite the considerable role of heredity in explaining individual differences in deceptive behavior, few studies have investigated which specific genes contribute to the heterogeneity of lying behavior across individuals. Also, little is known concerning which specific neurotransmitter pathways underlie deception. Towards addressing these two key questions, we implemented a neurogenetic strategy and modeled deception by an incentivized die-under-cup task in a laboratory setting. The results of this exploratory study provide provisional evidence that SNP variants across the tryptophan hydroxylase 2 (TPH2 gene, that encodes the rate-limiting enzyme in the biosynthesis of brain serotonin, contribute to individual differences in deceptive behavior.

  10. Bismalonamides (BISMA) as new extractants for Am(III) and Eu(III) from aqueous high-level wastes

    Energy Technology Data Exchange (ETDEWEB)

    Murillo, M.T.; Almaraz, M.; Sanchez-Quesada, J.; Segura, M.; Iglesias-Sanchez, J.C.; Mendoza, J. de; Prados, P. [Univ. Autonoma de Madrid (Spain). Dept. de Quimica Organica; Espartero, A.G. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Madrid (Spain)

    2008-07-01

    Bismalonamides 1-8 and bisthiomalonamides 9-13 were synthesised and studied as extracting agents for Am(III) and Eu(III) from nitric acid solutions into organic solvents. Bismalonamides 7a and 7g display higher distribution coefficients in chlorinated solvents than single malonamide DMDOHEMA, suggesting that bismalonamides could preorganise the binding groups around the cation more efficiently. Additionally, back-extraction of Am(III) and Eu(III) from a loaded organic solution of 7g in (50: 50){sub %} {sub vol} TPH/1-octanol mixture allowed to recover 99% of the initially extracted Am(III) and Eu(III) after three times of contact with fresh 0.01 mol/L nitric acid solutions. (orig.)

  11. NAD+ protects against EAE by regulating CD4+ T-cell differentiation

    Science.gov (United States)

    Tullius, Stefan G.; Biefer, Hector Rodriguez Cetina; Li, Suyan; Trachtenberg, Alexander J.; Edtinger, Karoline; Quante, Markus; Krenzien, Felix; Uehara, Hirofumi; Yang, Xiaoyong; Kissick, Haydn T.; Kuo, Winston P.; Ghiran, Ionita; de la Fuente, Miguel A.; Arredouani, Mohamed S.; Camacho, Virginia; Tigges, John C.; Toxavidis, Vasilis; El Fatimy, Rachid; Smith, Brian D.; Vasudevan, Anju; ElKhal, Abdallah

    2014-01-01

    CD4+ T cells are involved in the development of autoimmunity, including multiple sclerosis (MS). Here we show that nicotinamide adenine dinucleotide (NAD+) blocks experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing immune homeostasis through CD4+IFNγ+IL-10+ T cells and reverses disease progression by restoring tissue integrity via remyelination and neuroregeneration. We show that NAD+ regulates CD4+ T-cell differentiation through tryptophan hydroxylase-1 (Tph1), independently of well-established transcription factors. In the presence of NAD+, the frequency of T-bet−/− CD4+IFNγ+ T cells was twofold higher than wild-type CD4+ T cells cultured in conventional T helper 1 polarizing conditions. Our findings unravel a new pathway orchestrating CD4+ T-cell differentiation and demonstrate that NAD+ may serve as a powerful therapeutic agent for the treatment of autoimmune and other diseases. PMID:25290058

  12. Regulation of systemic energy homeostasis by serotonin in adipose tissues.

    Science.gov (United States)

    Oh, Chang-Myung; Namkung, Jun; Go, Younghoon; Shong, Ko Eun; Kim, Kyuho; Kim, Hyeongseok; Park, Bo-Yoon; Lee, Ho Won; Jeon, Yong Hyun; Song, Junghan; Shong, Minho; Yadav, Vijay K; Karsenty, Gerard; Kajimura, Shingo; Lee, In-Kyu; Park, Sangkyu; Kim, Hail

    2015-04-13

    Central serotonin (5-HT) is an anorexigenic neurotransmitter in the brain. However, accumulating evidence suggests peripheral 5-HT may affect organismal energy homeostasis. Here we show 5-HT regulates white and brown adipose tissue function. Pharmacological inhibition of 5-HT synthesis leads to inhibition of lipogenesis in epididymal white adipose tissue (WAT), induction of browning in inguinal WAT and activation of adaptive thermogenesis in brown adipose tissue (BAT). Mice with inducible Tph1 KO in adipose tissues exhibit a similar phenotype as mice in which 5-HT synthesis is inhibited pharmacologically, suggesting 5-HT has localized effects on adipose tissues. In addition, Htr3a KO mice exhibit increased energy expenditure and reduced weight gain when fed a high-fat diet. Treatment with an Htr2a antagonist reduces lipid accumulation in 3T3-L1 adipocytes. These data suggest important roles for adipocyte-derived 5-HT in controlling energy homeostasis.

  13. Anti-Apoptotic Protein Bcl-xL Expression in the Midbrain Raphe Region Is Sensitive to Stress and Glucocorticoids.

    Directory of Open Access Journals (Sweden)

    Galina T Shishkina

    Full Text Available Anti-apoptotic proteins are suggested to be important for the normal health of neurons and synapses as well as for resilience to stress. In order to determine whether stressful events may influence the expression of anti-apoptotic protein Bcl-xL in the midbrain and specifically in the midbrain serotonergic (5-HT neurons involved in neurobehavioral responses to adverse stimuli, adult male rats were subjected to short-term or chronic forced swim stress. A short-term stress rapidly increased the midbrain bcl-xl mRNA levels and significantly elevated Bcl-xL immunoreactivity in the midbrain 5-HT cells. Stress-induced increase in glucocorticoid secretion was implicated in the observed effect. The levels of bcl-xl mRNA were decreased after stress when glucocorticoid elevation was inhibited by metyrapone (MET, 150 mg/kg, and this decrease was attenuated by glucocorticoid replacement with dexamethasone (DEX; 0.2 mg/kg. Both short-term stress and acute DEX administration, in parallel with Bcl-xL, caused a significant increase in tph2 mRNA levels and slightly enhanced tryptophan hydroxylase immunoreactivity in the midbrain. The increasing effect on the bcl-xl expression was specific to the short-term stress. Forced swim repeated daily for 2 weeks led to a decrease in bcl-xl mRNA in the midbrain without any effects on the Bcl-xL protein expression in the 5-HT neurons. In chronically stressed animals, an increase in tph2 gene expression was not associated with any changes in tryptophan hydroxylase protein levels. Our findings are the first to demonstrate that both short-term stress and acute glucocorticoid exposures induce Bcl-xL protein expression in the midbrain 5-HT neurons concomitantly with the activation of the 5-HT synthesis pathway in these neurons.

  14. Tryptophan metabolism in breast cancers: molecular imaging and immunohistochemistry studies

    International Nuclear Information System (INIS)

    Introduction: Tryptophan oxidation via the kynurenine pathway is an important mechanism of tumoral immunoresistance. Increased tryptophan metabolism via the serotonin pathway has been linked to malignant progression in breast cancer. In this study, we combined quantitative positron emission tomography (PET) with tumor immunohistochemistry to analyze tryptophan transport and metabolism in breast cancer. Methods: Dynamic α-[11C]methyl-L-tryptophan (AMT) PET was performed in nine women with stage II–IV breast cancer. PET tracer kinetic modeling was performed in all tumors. Expression of L-type amino acid transporter 1 (LAT1), indoleamine 2,3-dioxygenase (IDO; the initial and rate-limiting enzyme of the kynurenine pathway) and tryptophan hydroxylase 1 (TPH1; the initial enzyme of the serotonin pathway) was assessed by immunostaining of resected tumor specimens. Results: Tumor AMT uptake peaked at 5–20 min postinjection in seven tumors; the other two cases showed protracted tracer accumulation. Tumor standardized uptake values (SUVs) varied widely (2.6–9.8) and showed a strong positive correlation with volume of distribution values derived from kinetic analysis (P < .01). Invasive ductal carcinomas (n = 6) showed particularly high AMT SUVs (range, 4.7–9.8). Moderate to strong immunostaining for LAT1, IDO and TPH1 was detected in most tumor cells. Conclusions: Breast cancers show differential tryptophan kinetics on dynamic PET. SUVs measured 5–20 min postinjection reflect reasonably the tracer's volume of distribution. Further studies are warranted to determine if in vivo AMT accumulation in these tumors is related to tryptophan metabolism via the kynurenine and serotonin pathways.

  15. Local serotonin mediates cyclic strain-induced phenotype transformation, matrix degradation, and glycosaminoglycan synthesis in cultured sheep mitral valves.

    Science.gov (United States)

    Lacerda, Carla M R; Kisiday, John; Johnson, Brennan; Orton, E Christopher

    2012-05-15

    This study addressed the following questions: 1) Does cyclic tensile strain induce protein expression patterns consistent with myxomatous degeneration in mitral valves? 2) Does cyclic strain induce local serotonin synthesis in mitral valves? 3) Are cyclic strain-induced myxomatous protein expression patterns in mitral valves dependent on local serotonin? Cultured sheep mitral valve leaflets were subjected to 0, 10, 20, and 30% cyclic strain for 24 and 72 h. Protein levels of activated myofibroblast phenotype markers, α-smooth muscle actin (α-SMA) and nonmuscle embryonic myosin (SMemb); matrix catabolic enzymes, matrix metalloprotease (MMP) 1 and 13, and cathepsin K; and sulfated glycosaminoglycan (GAG) content in mitral valves increased with increased cyclic strain. Serotonin was present in the serum-free media of cultured mitral valves and concentrations increased with cyclic strain. Expression of the serotonin synthetic enzyme tryptophan hydroxylase 1 (TPH1) increased in strained mitral valves. Pharmacologic inhibition of the serotonin 2B/2C receptor or TPH1 diminished expression of phenotype markers (α-SMA and SMemb) and matrix catabolic enzyme (MMP1, MMP13, and cathepsin K) expression in 10- and 30%-strained mitral valves. These results provide first evidence that mitral valves synthesize serotonin locally. The results further demonstrate that tensile loading modulates local serotonin synthesis, expression of effector proteins associated with mitral valve degeneration, and GAG synthesis. Inhibition of serotonin diminishes strain-mediated protein expression patterns. These findings implicate serotonin and tensile loading in mitral degeneration, functionally link the pathogeneses of serotoninergic (carcinoid, drug-induced) and degenerative mitral valve disease, and have therapeutic implications.

  16. Peripheral serotonin regulates maternal calcium trafficking in mammary epithelial cells during lactation in mice.

    Directory of Open Access Journals (Sweden)

    Jimena Laporta

    Full Text Available Lactation is characterized by massive transcellular flux of calcium, from the basolateral side of the mammary alveolar epithelium (blood into the ductal lumen (milk. Regulation of calcium transport during lactation is critical for maternal and neonatal health. The monoamine serotonin (5-HT is synthesized by the mammary gland and functions as a homeostatic regulation of lactation. Genetic ablation of tryptophan hydroxylase 1 (Tph1, which encodes the rate-limiting enzyme in non-neuronal serotonin synthesis, causes a deficiency in circulating serotonin. As a consequence maternal calcium concentrations decrease, mammary epithelial cell morphology is altered, and cell proliferation is decreased during lactation. Here we demonstrate that serotonin deficiency decreases the expression and disrupts the normal localization of calcium transporters located in the apical (PMCA2 and basolateral (CaSR, ORAI-1 membranes of the lactating mammary gland. In addition, serotonin deficiency decreases the mRNA expression of calcium transporters located in intracellular compartments (SERCA2, SPCA1 and 2. Mammary expression of serotonin receptor isoform 2b and its downstream pathways (PLCβ3, PKC and MAP-ERK1/2 are also decreased by serotonin deficiency, which might explain the numerous phenotypic alterations described above. In most cases, addition of exogenous 5-hydroxy-L-tryptophan to the Tph1 deficient mice rescued the phenotype. Our data supports the hypothesis that serotonin is necessary for proper mammary gland structure and function, to regulate blood and mammary epithelial cell transport of calcium during lactation. These findings can be applicable to the treatment of lactation-induced hypocalcemia in dairy cows and can have profound implications in humans, given the wide-spread use of selective serotonin reuptake inhibitors as antidepressants during pregnancy and lactation.

  17. The role of mechanical forces and adenosine in the regulation of intestinal enterochromaffin cell serotonin secretion.

    Science.gov (United States)

    Chin, A; Svejda, B; Gustafsson, B I; Granlund, A B; Sandvik, A K; Timberlake, A; Sumpio, B; Pfragner, R; Modlin, I M; Kidd, M

    2012-02-01

    Enterochromaffin (EC) cells of the diffuse neuroendocrine cell system secrete serotonin (5-HT) with activation of gut motility, secretion, and pain. These cells express adenosine (ADORA) receptors and are considered to function as mechanosensors. Physiological pathways mediating mechanosensitivity and adenosine responsiveness remain to be fully elucidated, as do their roles in inflammatory bowel disease (IBD) and neoplasia. Pure (98-99%) FACS-sorted normal and IBD human EC cells and neoplastic EC cells (KRJ-I) were studied. IBD-EC cells and KRJ-I overexpressed ADORA2B. NECA, a general ADORA receptor agonist, stimulated, whereas the A2B receptor antagonist MRS1754 inhibited, 5-HT release (EC50 = 1.8 × 10-6 M; IC50 = 3.7 × 10-8 M), which was associated with corresponding alterations in intracellular cAMP levels and pCREB (Ser133). Mechanical stimulation using a rhythmic flex model induced transcription and activation of Tph1 (tryptophan hydroxylase) and VMAT₁ (vesicular monoamine transporter 1) and the release of 5-HT, which could be inhibited by MRS1754 and amplified by NECA. Secretion was also inhibited by H-89 (PKA inhibitor) while Tph1 and VMAT₁ transcription was regulated by PKA/MAPK and PI₃K-mediated signaling. Normal and IBD-EC cells also responded to NECA and mechanical stimulation with PKA activation, cAMP production, and 5-HT release, effects reversible by MRS1754. EC cells express stimulatory ADORA2B, and rhythmic stretch induces A2B activation, PKA/MAPK/IP3-dependent transcription, and PKA-dependent secretion of 5-HT synthesis and secretion. Receptor expression is amplified in IBD and neoplasia, and 5-HT release is increased. Determination of factors that regulate EC cell function are necessary for understanding its role as a mechanosensory cell and to facilitate the development of agents that can selectively target cell function in EC cell-associated disease. PMID:22038827

  18. The initial building and application of the DNA specimen database in Uygur Chinese population with depression%新疆维吾尔族抑郁症基因样本库的初步建立及应用

    Institute of Scientific and Technical Information of China (English)

    张丽丽; 韩书贤; 安治国; 钟衔江; 罗晓; 伊琦忠

    2014-01-01

    Objective To built up the normative DNA specimen bank of Uyghur population with depression initially,and to analyze the polymorphism of TPH-2 gene.Methods 800 Uyghur patients with depression were collected by the demography,clinical data and DNA specimens from January,2010 to January 2013. After quality control,DNA specimens were retained in the vital diseases repository of the first Affiliated Hospital to Xinjiang Medical University,then we set up the clinical data repository,and assessed the pos-sible risk factors of the disease.According to direct DAN sequencing ,we investigated the association be-tween the polymorphism of TPH-2 gene and suicidal tendencies of depression.Results (1)The result of preliminary application shows that 99.6% of samples were genotyped successfully for rs7305115.(2)The significant differences of HAMD-1 7 scores were found between groups with different educational back-ground or professions (P 0.05).(4)rs7305115 was not found to have genotypic or al-lelic association with suicidal tendencies between the cases with suicide intension and those without (P >0.05).Conclusion The normative DNA specimen database of Uyghur population with depression was built up initially.Literacy level and social status were associated with the condition of the disease.But it failed to find the correlation between TPH-2 gene and depression.%目的:初步建立标准的新疆维吾尔族抑郁症 DNA样品库,并进行 TPH-2基因多态性的研究。方法收集2010年1月-2013年1月于新疆医科大学第一附属医院精神科及新疆其他精神病院治疗的800例维吾尔族抑郁症患者的一般人口学资料、临床信息及DNA样本。DNA样品经质量控制后,保存于新疆医科大学第一附属医院重大疾病资源标本库,并建立与之一一对应的临床资料数据库,进行危险因素的评估。采用 DNA直接测序法进行TPH-2基因多态性与抑郁症自杀倾向的关联性研究。结果(1)

  19. 色氨酸羟化酶1与5-羟色胺2A受体基因对抑郁症患者额叶情绪加工的影响%The impact of tryptophan hydroxylase 1 gene and serotonin receptor 2A gene on emotional process in depressive frontal lobe

    Institute of Scientific and Technical Information of China (English)

    唐勇; 张婧; 姚志剑; 刘海燕

    2011-01-01

    Objective: To explore the genetic impact of tryptophan hydroxylase 1 gene(TPHl) A218C, serotonin receptor 2A gene (HTR2A) T102C on abnormal frontal lobe of depressed patients in emotion recog-nization. Method:28 patients with major depression and 34 healthy controls were recruited in our study, which were equal in sex, age, years of education. They all underwent functional magnetic resonance imaging (fMRl) in emotion recognition and were divided into different genotypes with the method of polymerase chain reaction and restriction fragment length polymorphism. The frontal lobe was extracted as region of interest by WFU software into six subregions to compare differences among different groups. Results :①In recognition of happy facial expression,activation of right middle frontal gyms in patients with TPH1AA genotype was less than other five groups. Activation in patients with HTR2ACC genotype was less than patients and controls with AA or AC genotype (P<0.05).② In recognition of sad facial expression,patients and controls with TPH1AA genotype showed increased activation in left inferior frontal lobe than those with AC or CC genotype. Patients with AA genotype showed increased activation in right inferior frontal gyurs than other five groups as well. Patients with HTR2ACC genotype showed increase activation in right middle frontal gyrus than patients with TT of TC genotype and controls with TT genotype,showing increase activation in right inferior frontal gyrus than those with TT or TC genotype (P<0.05).③Superimposition of TPH1A218C and HTR2AT102C was found in abnormal function of right middle frontal gyrus when recognizing positive emotional stimuli and right inferior grontal gyrus when recognizing negative emotional stimuli (P<0.05). Conclusion:Frontal lobe in depressive disorder has the genetic basis of 5-HT to some extent Different genes in serotonin system can affect brain function through a common 5-HT feature.%目的:分析色氨酸羟化酶1 (TPH1)

  20. Effects of antidepressant therapy on serotonin and tryptophan hydroxylase 2 in ovariectomized rats with depressive disorder%抗抑郁剂对去卵巢抑郁模型大鼠色氨酸羟化酶2和血清素的影响

    Institute of Scientific and Technical Information of China (English)

    万砚; 谢利娜; 王艺明

    2016-01-01

    Obiective To investigate the effects of antidepressant therapy on whole regulating function of serotonin and tryptophan hydroxylase 2 system in ovariectomized(OVX) rats with depressive disorder.Methods seventy-two female Sprague-Dawley rats were used as subjects.The rats were randomly divided in-to 8 groups as following:Sham operation group (Sn),depression group (Dn),the OVX group (On),OVX with depression group (ODn),OVX with depression + sertraline group (ODs),OVX with depression + citalopram group(ODx),OVX with depression+ venlafaxine group(ODw),OVX with depression+ reboxetine group(0Dr).Rats in group OVX and group OVX with depression were ovariectomized.Rats in group with depression were exposed to the chronic unpredictable mild stress (CUMS).Open-field test and sugar consumption experiment were tested on all rats before the experiment and the 28th day of experiment.The expression of TPH2 mRNA was measured with RT-PCR,and the expression of TPH2 protein was detected by Western blot.The concentration of 5-HT was detected by ELISA.Results (1) After exposure of CUMS,the scores of motion and percentage of sugar consumption experiment in Dn group were decreased contrast to the Sn group (P<0.05),and the scores in ODn group were decreased compared with the on group(P<0.05).(2)The protein and gene expression of THP2 in On and Dn group were decreased contrast to the Sn group (P<0.05).The protein and gene expression of THP2 in ODn were decreased compared with the on group (P<0.05).The protein and gene expression of THP2 in ODs (protein (0.68±0.07);gene (0.87±0.09)),ODx (protein (0.71 ±0.05);gene (0.84±0.17)),ODw(protein (0.69±0.04);gene (0.88±0.16)) and ODr(protein (0.53±0.07);gene (0.70±0.15)) were increased compared with the ODn(protein (0.31±0.09);gene (0.56±O.16)) group (P<0.05).(3)The concentration of 5-HT of hippocampus and serum in Dn and On group were decreased contrast to the Sn group (P<0.05).The concentration of 5-HT of hippocampus and

  1. Antipsychotic-induced behavioral sensitization and tolerance and the related neurobiological mechanisms%抗精神病药长期使用引起的敏化和耐受效果及其相关机制

    Institute of Scientific and Technical Information of China (English)

    高军; 李鸣

    2014-01-01

    Antipsychotics are the medications that are used to treat schizophrenia.How they work to achieve their therapeutic effects has not been adequately addressed.Like other psychoactive drugs,repeated administration of these drugs can induce various clinically relevant sensitization and tolerance effects in many behavioral domains.In recent years,we have used the conditioned avoidance response (CAR)and phencyclidine (PCP)-induced hyperlocomotion,two models with high predictive validity for antipsychotic efficacy and examined the long-term treatment effects of antipsychotic drugs.In this paper,I discuss our animal work on the behavioral characteristics and neuroreceptor mechanisms of antipsychotic sensitiza-tion and tolerance,as well as their developmental impacts from adolescence into adulthood.I highlight our work on the roles of dopamine D2 receptors and serotonin 5-HT2A receptors in the medial prefrontal cortex and nucleus accumbens in the induction and expression of antipsychotic sensitization and tolerance.%抗精神病药已经有60余年的使用历史,应用于治疗精神分裂症及其他精神疾病伴随的幻觉、妄想症等症状。临床和动物研究都提示抗精神病药的长期使用会导致个体对药物的敏感性发生变化,即产生敏化或耐受效果。在急性用药情况下,多种临床常用抗精神病药作用都可以抑制条件躲避反应和苯环利定诱发的运动增强。以这两个动物模型为基础,我们建立了研究抗精神病药敏化和耐受的行为学范式。以此为基础,我们一系列研究发现长期用药可导致药物敏感性加强或减弱,即敏化或耐受。并进一步考察了敏化和耐受的行为学特征及其神经生物学基础。结果表明大多数抗精神病药长期用药会导致敏化,这些药物包括:奥氮平、阿塞那平、阿立哌唑、利培酮、氟哌啶醇等,而只有氯氮平会导致耐受。在行为学层面,敏化和耐受在不同

  2. The glycine transporter-1 inhibitors NFPS and Org 24461: a pharmacological study.

    Science.gov (United States)

    Harsing, Laszlo G; Gacsalyi, Istvan; Szabo, Geza; Schmidt, Eva; Sziray, Nora; Sebban, Claude; Tesolin-Decros, Brigitte; Matyus, Peter; Egyed, Andras; Spedding, Michael; Levay, Gyorgy

    2003-03-01

    The in vitro and in vivo pharmacology of two glycine transporter-1 (GlyT1) inhibitors, N[3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)-propyl]sarcosine (NFPS) and R,S-(+/-)N-methyl-N-[(4-trifluoromethyl)phenoxy]-3-phenyl-propylglycine (Org 24461), was studied. NFPS and Org 24461 inhibited the uptake of [3H]glycine in hippocampal synaptosomal preparation with IC(50) values of 0.022 and 2.5 microM. Neither NFPS nor Org 24461 (0.1 microM) showed significant binding to alpha-1, alpha-2, and beta-adrenoceptors, D(1) and D(2) dopamine receptors, and 5-HT(1A) and 5-HT(2A) serotonin receptors in membranes prepared from rat brain or to cloned 5-HT(6) and 5-HT(7) receptors. At 10 microM concentrations, binding affinity was measured for NFPS to 5-HT(2A) and 5-HT(2C) serotonin receptors and alpha-2 adrenoceptors and for NFPS and Org 24461 to 5-HT(7) serotonin receptors. Glycine (0.1 mM) and sarcosine (5 mM) increased [3H]glycine efflux from superfused rat hippocampal slices preloaded with [3H]glycine. NFPS and Org 24461 (0.1 mM) did not influence [3H]glycine efflux, however, they inhibited glycine-induced [3H]glycine release. These findings indicate that NFPS and Org 24461 selectively inhibit glycine uptake without being substrates of the transporter protein. Several antipsychotic tests were used to characterize antipsychotic effects of NFPS and Org 24461 in vivo. These compounds did not alter apomorphine-induced climbing and stereotypy in a dose of 10 mg/kg p.o. in mice and did not induce catalepsy in a dose of 10 mg/kg i.p. in rats. The ID(50) values of NFPS were 21.4 mg/kg and higher than 30 mg/kg i.p. for inhibition of phencyclidine (PCP)- and D-amphetamine-induced hypermotility in mice and these values were 2.5 and 8.6 mg/kg i.p. for Org 24461. NFPS and Org 24461 did not exhibit anxiolytic effects in light-dark test in mice, in the meta-chlorophenylpiperazine (mCPP)-induced anxiety test (minimal effective dose or MED was higher than 3 mg/kg i.p.) and in the Vogel conflict

  3. Vasoactivity and Vasoconstriction Changes in Cattle Related to Time off Toxic Endophyte-Infected Tall Fescue.

    Science.gov (United States)

    Klotz, James L; Aiken, Glen E; Bussard, Jessica R; Foote, Andrew P; Harmon, David L; Goff, Ben M; Schrick, F Neal; Strickland, James R

    2016-01-01

    Previous research has indicated that serotonergic and α-adrenergic receptors in peripheral vasculature are affected by exposure of cattle grazing toxic endophyte-infected (E+; Epichlöe coenophialia) tall fescue (Lolium arundinaceum). The objective of this experiment was to determine the period of time necessary for the vascular effects of ergot alkaloids to subside. Two experiments were conducted to investigate changes in vascular contractile response and vasoconstriction over time relative to removal from an ergot alkaloid-containing E+ tall fescue pasture. In Experiment 1, lateral saphenous vein biopsies were conducted on 21 predominantly Angus steers (357 ± 3 kg body weight) at 0 (n = 6), 7 (n = 6), 14 (n = 5), or 28 days (n = 4) after removal from grazing pasture (3.0 ha; endpoint ergovaline + ergovalinine = 1.35 mg/kg DM) for 126 days. In Experiment 2, lateral saphenous veins were biopsied from 24 Angus-cross steers (361 ± 4 kg body weight) at 0, 21, 42, and 63 days (n = 6 per time point) following removal from grazing tall fescue pastures (3.0 ha; first 88 days endpoint ergovaline + ergovalinine = 0.15 mg/kg DM; last 18 days endpoint ergovaline + ergovalinine = 0.57 mg/kg DM) for 106 total days. Six steers (370 ± 18 kg body weight) off of bermudagrass pasture for the same time interval were also biopsied on Day 0 and Day 63 (n = 3 per time point). Additionally, in Experiment 2, cross-sectional ultrasound scans of caudal artery at the fourth coccygeal vertebra were taken on Days 0, 8, 15, 21, 29, 36, 42, and 45 to determine mean artery luminal area to evaluate vasoconstriction. In both experiments, steers were removed from pasture and housed in a dry lot and fed a corn silage diet for the duration of biopsies and ultrasound scans. Biopsied vessels used to evaluate vasoactivity were cleaned, incubated in a multimyograph, and exposed to increasing concentrations of 4-Bromo-3,6-dimethoxybenzocyclobuten-1-yl) methylamine hydrobromide (TCB2; 5HT2A agonist

  4. Role of the serotoninergic system in the sodium appetite control

    Directory of Open Access Journals (Sweden)

    Luís C. Reis

    2007-06-01

    Full Text Available The present article reviews the role of the serotoninergic system in the regulation of the sodium appetite. Data from the peripheral and icv administration of serotoninergic (5-HTergic agents showed the participation of 5-HT2/3 receptors in the modulation of sodium appetite. These observations were extended with the studies carried out after brain serotonin depletion, lesions of DRN and during blockade of 5-HT2A/2C receptors in lateral parabrachial nucleus (LPBN. Brain serotonin depletion and lesions of DRN increased the sodium appetite response, in basal conditions, after sodium depletion and hypovolemia or after beta-adrenergic stimulation as well. These observations raised the hypothesis that the suppression of ascending pathways from the DRN, possibly, 5-HTergic fibers, modifies the angiotensinergic or sodium sensing mechanisms of the subfornical organ involved in the control of the sodium appetite. 5-HTergic blockade in LPBN induced to similar results, particularly those regarded to the natriorexigenic response evoked by volume depletion or increase of the hypertonic saline ingestion induced by brain angiotensinergic stimulation. In conclusion, many evidences lead to acceptation of an integrated participation resulting of an interaction, between DRN and LPBN, for the sodium appetite control.Este artigo revisa o papel do sistema serotoninérgico no controle do apetite ao sódio. Dados derivados da administração periférica e icv de agentes serotoninérgicos demonstraram a participação de receptores 5-HT2/3 na modulação do apetite ao sódio. Estas observações foram estendidas com os estudos realizados após a depleção cerebral de serotonina, lesões do NDR e durante o bloqueio 5-HT2A/2C no núcleo parabraquial lateral (NPBL. A depleção cerebral de serotonina e as lesões do NDR aumentaram o apetite ao sódio, em condições basais, após depleção de sódio, durante a hipovolemia ou após a estimulação beta-adrenérgica. Estas

  5. 强迫症与5-羟色胺受体基因的关联研究

    Institute of Scientific and Technical Information of China (English)

    刘薇; 郭烽炜; 王吉囡; 李艳华; 陈力; 胡建

    2007-01-01

    目的 探讨北方汉族人群中5-HT2A、5-HT2C、5-HT1Dβ受体基因与强迫症(OCD)的相关性.方法 采用聚合酶链反应-限制性片段长度多态技术测定225例强迫症患者和175名正常对照的5-HT2A-1438G/A、5-HT2cCys23Ser、5-HT1DβG861C多态性的基因型,根据强迫症的共病情况、发病年龄、临床表现将OCD划分亚型进行与5-羟色胺受体基因多态性的关联分析.结果 OCD组5-HT1Dβ等位基因861C频率与对照组有显著性差异(x2=4.39,P=0.04).而5-HT2A、5-HT2C 2个位点基因型和等位基因及5-HT1Dβ基因型的频率与对照组之间差异无显著性(P>0.05);OCD共病其他精神障碍组5-HT1Dβ基因型与等位基因频率与对照组有显著性差异(x2=7.12,P=0.03;x2=7 56,P=0.006),而无共病组3个位点基因型与等位基因频率与对照组无显著性差异(P>0.05);早发OCD组5-HT2A基因型和等位基因频率与对照组有显著性差异(x2=8.97,P=0.01;x2=8.05,P=0.005);强迫思维合并强迫行为的患者5-HT2A基因型与等位基因频率与对照组有显著性差异(x2=9.15,P=0.01;x2=8.38,P=0.004).结论 5-HT2A-1438G/A多态性与强迫思维合并强迫行为的OCD亚型及早发型OCD的发病存在关联;5-HT1DβG861C多态性与共病其他精神障碍的OCD相关,有/无共病强迫症可能有不同的发病机制.

  6. Update on extended release quetiapine fumarate in schizophrenia and bipolar disorders

    Directory of Open Access Journals (Sweden)

    El-Khalili N

    2012-11-01

    Full Text Available Nizar El-KhaliliAlpine Clinic, Lafayette, IN, USAAbstract: The atypical antipsychotic quetiapine fumarate is available both as an immediate release (IR and as an extended release (XR formulation allowing flexibility of dosing for individual patients. Approved uses of quetiapine XR include the treatment of schizophrenia (including maintenance therapy for prevention of relapse, the treatment of bipolar disorder (manic and depressive episodes, and the prevention of recurrence in patients with bipolar disorder who respond to quetiapine XR. This narrative review provides an update on quetiapine XR in these indications. The pharmacological profile of quetiapine, including a moderate affinity for dopamine D2 receptors and higher affinity for serotonin 5-hydroxytryptophan (5-HT2A receptors, may explain its broad efficacy and low propensity for extrapyramidal symptoms (EPS. The XR formulation has similar bioavailability but prolonged plasma levels compared with the IR formulation, allowing for less frequent (once-daily dosing. Clinical studies have confirmed the efficacy of quetiapine XR in relieving the acute symptoms of schizophrenia during short-term trials, and reducing the risk for relapse in long-term studies. Direct switching from the IR formulation to the same dose of the XR formulation did not reveal any loss of efficacy or tolerability issues, and switching patients to quetiapine XR from conventional or other atypical antipsychotics (for reasons of insufficient efficacy or tolerability also proved to be beneficial and generally well tolerated. In bipolar disorder, quetiapine XR has also proven effective in relieving acute depressive and manic symptoms. Adverse events with quetiapine XR in patients with either schizophrenia or bipolar disorder are similar to those associated with the IR formulation, the most common being sedation, dry mouth, somnolence, dizziness, and headache. The low propensity for EPS is maintained with the XR formulation

  7. Critical appraisal of lurasidone in the management of schizophrenia

    Directory of Open Access Journals (Sweden)

    Caccia S

    2012-04-01

    Full Text Available Silvio Caccia, Luca Pasina, Alessandro NobiliIstituto di Ricerche Farmacologiche, “Mario Negri”, Milan, ItalyAbstract: Lurasidone is a new atypical antipsychotic in the benzoisothiazoles class of chemicals. Like most second-generation antipsychotics it is a full antagonist at dopamine D2 and serotonin 5-HT2A receptors, and is a partial agonist at 5-HT1A receptors, a property shared by some but not all older agents. It has much greater affinity for 5-HT7 subtype receptors than other atypical antipsychotics. Pharmacokinetic studies showed that lurasidone is reasonably rapidly absorbed, with bioavailability appearing to be increased by food. Lurasidone undergoes extensive metabolism to a number of metabolites, some of which retain pharmacological activities. Metabolism is mainly by CYP3A4, resulting in steady-state concentrations that vary between individuals and are potentially affected by strong inducers and inhibitors of this enzyme. Short-term clinical trials have demonstrated the efficacy of lurasidone in acute schizophrenia, with doses of 40 and 80 mg/day giving significant improvements from baseline in the PANSS and BPRS scores. The most common adverse events are nausea, vomiting, akathisia, dizziness, and sedation, with minimal increases in the risk of developing metabolic syndrome. Lurasidone did not raise the risk of QTc interval prolongation, although additional studies are required. Long-term trials are also needed to assess the risk of new-onset diabetes. Ongoing trials in patients with bipolar disorder are being completed but, again, efficacy and safety have been investigated only in a few short-term clinical trials.Keywords: lurasidone, pharmacology, pharmacokinetics, efficacy, safety

  8. Spotlight on brexpiprazole and its potential in the treatment of schizophrenia and as adjunctive therapy for the treatment of major depression.

    Science.gov (United States)

    Bruijnzeel, Dawn; Tandon, Rajiv

    2016-01-01

    Antipsychotic agents, utilized for the treatment of a range of psychiatric disorders, differ substantially in terms of their pharmacology and adverse effect profiles. Incomplete and variable efficacy, differences in safety-tolerability, and highly heterogeneous response across individuals prompt development of new agents. Brexpiprazole is one of the two most recently introduced antipsychotic agents approved for the treatment of schizophrenia and as an adjunct for treatment of major depressive disorder. Its pharmacology, clinical trial data, and efficacy and side effects in comparison with other antipsychotic agents are discussed. Brexpiprazole is a dopamine D-2 partial agonist with potent activity at the serotonin 5HT1A and 5HT2A and noradrenergic alpha-1B and alpha-2C receptors. Placebo-controlled clinical trials in persons with schizophrenia support its efficacy in treating psychosis and preventing relapse. Short-term clinical trials also support its efficacy as an adjunct to antidepressants in treating major depressive disorder in individuals inadequately responsive to antidepressant treatment alone. Adverse effects include akathisia, gastrointestinal side effects, and moderate weight gain. The recommended oral dose of brexpiprazole is 2-4 mg/day in schizophrenia and 2-3 mg/day as adjunctive treatment in major depression. It must be titrated up to its target dose over 1-2 weeks and is effective in once-daily dosing. How brexpiprazole's unique pharmacological profile will translate into clinically meaningful differences from other antipsychotic agents is unclear. Its place in our antipsychotic armamentarium and potential role in the treatment of schizophrenia and major depressive disorder will be determined by additional clinical data and experience.

  9. Asparagus racemosus attenuates anxiety-like behavior in experimental animal models.

    Science.gov (United States)

    Garabadu, Debapriya; Krishnamurthy, Sairam

    2014-05-01

    Asparagus racemosus Linn. (AR) is used worldwide as a medicinal plant. In the present study, the anxiolytic activity of standardized methanolic extract of root of AR (MAR) was evaluated in open-field test (OFT), hole-board, and elevated plus maze (EPM) tests. Rats received oral pretreatment of MAR in the doses of 50, 100, and 200 mg/kg daily for 7 days and then were evaluated for the anxiolytic activity in different animal models. Both MAR (100 and 200 mg/kg) and diazepam (1 mg/kg, p.o.) increased the grooming behavior, number of central squares crossed, and time spent in the central area during OFT. Further, MAR (100 and 200 mg/kg) increased the head-dip and head-dip/sniffing behavior, and decreased sniffing activity in hole-board test. Furthermore, MAR (100 and 200 mg/kg) increased the percentage entries and time spent to open arm in EPM test paradigm. The anxiolytic activity in the experimental models was similar to that of diazepam. MAR (100 and 200 mg/kg) enhanced the level of amygdalar serotonin and norepinephrine. It also increased the expression of 5-HT2A receptors in the amygdala. In another set of experiment, flumazenil attenuated the anxiolytic effect of minimum effective dose of MAR (100 mg/kg) in OFT, hole-board, and EPM tests, indicating GABAA-mediated mechanism. Moreover, the anxiolytic dose of MAR did not show sedative-like effect in OFT and EPM tests compared to diazepam (6 mg/kg, p.o.). Thus, the anxiolytic response of MAR may involve GABA and serotonergic mechanisms. These preclinical data show that AR can be a potential agent for treatment of anxiety disorders.

  10. Intra- and Interhemispheric Propagation of Electrophysiological Synchronous Activity and Its Modulation by Serotonin in the Cingulate Cortex of Juvenile Mice

    Science.gov (United States)

    Rovira, Víctor; Geijo-Barrientos, Emilio

    2016-01-01

    Disinhibition of the cortex (e.g., by GABA -receptor blockade) generates synchronous and oscillatory electrophysiological activity that propagates along the cortex. We have studied, in brain slices of the cingulate cortex of mice (postnatal age 14–20 days), the propagation along layer 2/3 as well as the interhemispheric propagation through the corpus callosum of synchronous discharges recorded extracellularly and evoked in the presence of 10 μM bicuculline by electrical stimulation of layer 1. The latency of the responses obtained at the same distance from the stimulus electrode was longer in anterior cingulate cortex (ACC: 39.53 ± 2.83 ms, n = 7) than in retrosplenial cortex slices (RSC: 21.99 ± 2.75 ms, n = 5; p<0.05), which is equivalent to a lower propagation velocity in the dorso-ventral direction in ACC than in RSC slices (43.0 mm/s vs 72.9 mm/s). We studied the modulation of this propagation by serotonin. Serotonin significantly increased the latency of the intracortical synchronous discharges (18.9% in the ipsilateral hemisphere and 40.2% in the contralateral hemisphere), and also increased the interhemispheric propagation time by 86.4%. These actions of serotonin were mimicked by the activation of either 5-HT1B or 5-HT2A receptors, but not by the activation of the 5-HT1A subtype. These findings provide further knowledge about the propagation of synchronic electrical activity in the cerebral cortex, including its modulation by serotonin, and suggest the presence of deep differences between the ACC and RSC in the structure of the local cortical microcircuits underlying the propagation of synchronous discharges. PMID:26930051

  11. The hallucinogenic world of tryptamines: an updated review.

    Science.gov (United States)

    Araújo, Ana Margarida; Carvalho, Félix; Bastos, Maria de Lourdes; Guedes de Pinho, Paula; Carvalho, Márcia

    2015-08-01

    In the area of psychotropic drugs, tryptamines are known to be a broad class of classical or serotonergic hallucinogens. These drugs are capable of producing profound changes in sensory perception, mood and thought in humans and act primarily as agonists of the 5-HT2A receptor. Well-known tryptamines such as psilocybin contained in Aztec sacred mushrooms and N,N-dimethyltryptamine (DMT), present in South American psychoactive beverage ayahuasca, have been restrictedly used since ancient times in sociocultural and ritual contexts. However, with the discovery of hallucinogenic properties of lysergic acid diethylamide (LSD) in mid-1900s, tryptamines began to be used recreationally among young people. More recently, new synthetically produced tryptamine hallucinogens, such as alpha-methyltryptamine (AMT), 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and 5-methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT), emerged in the recreational drug market, which have been claimed as the next-generation designer drugs to replace LSD ('legal' alternatives to LSD). Tryptamine derivatives are widely accessible over the Internet through companies selling them as 'research chemicals', but can also be sold in 'headshops' and street dealers. Reports of intoxication and deaths related to the use of new tryptamines have been described over the last years, raising international concern over tryptamines. However, the lack of literature pertaining to pharmacological and toxicological properties of new tryptamine hallucinogens hampers the assessment of their actual potential harm to general public health. This review provides a comprehensive update on tryptamine hallucinogens, concerning their historical background, prevalence, patterns of use and legal status, chemistry, toxicokinetics, toxicodynamics and their physiological and toxicological effects on animals and humans. PMID:25877327

  12. The study of genetic polymorphisms related to serotonin in Alzheimer's disease: a new perspective in a heterogenic disorder.

    Science.gov (United States)

    Oliveira, J R; Zatz, M

    1999-04-01

    Genetic and environmental factors have been implicated in the development of Alzheimer's disease (AD), the most common form of dementia in the elderly. Mutations in 3 genes mapped on chromosomes 21, 14 and 1 are related to the rare early onset forms of AD while the epsilon 4 allele of the apolipoprotein E (APOE) gene (on chromosome 19) is the major susceptibility locus for the most common late onset AD (LOAD). Serotonin (5-hydroxytryptamine or 5-HT) is a key neurotransmitter implicated in the control of mood, sleep, appetite and a variety of traits and behaviors. Recently, a polymorphism in the transcriptional control region upstream of the 5-HT transporter (5-HTT) gene has been studied in several psychiatric diseases and personality traits. It has been demonstrated that the short variant(s) of this 5-HTT gene-linked polymorphic region (5-HTTLPR) is associated with a different transcriptional efficiency of the 5-HTT gene promoter resulting in decreased 5-HTT expression and 5-HT uptake in lymphocytes. An increased frequency of this 5-HTTLPR short variant polymorphism in LOAD was recently reported. In addition, another common polymorphic variation in the 5-HT2A and 5-HT2C serotonin receptor genes previously analyzed in schizophrenic patients was associated with auditory and visual hallucinations in AD. These observations suggest that the involvement of the serotonin pathway might provide an explanation for some aspects of the affective symptoms commonly observed in AD patients. In summary, research on genetic polymorphisms related to AD and involved in receptors, transporter proteins and the enzymatic machinery of serotonin might enhance our understanding of this devastating neurodegenerative disorder.

  13. Possible involvement of serotonin 5-HT2 receptor in the regulation of feeding behavior through the histaminergic system.

    Science.gov (United States)

    Murotani, Tomotaka; Ishizuka, Tomoko; Isogawa, Yuka; Karashima, Michitaka; Yamatodani, Atsushi

    2011-01-01

    The central histaminergic system has been proven to be involved in several physiological functions including feeding behavior. Some atypical antipsychotics like risperidone and aripiprazole are known to affect feeding behavior and to antagonize the serotonin (5-HT) receptor subtypes. To examine the possible neural relationship between the serotonergic and histaminergic systems in the anorectic effect of the antipsychotics, we studied the effect of a single administration of these drugs on food intake and hypothalamic histamine release in mice using in vivo microdialysis. Single injection of risperidone (0.5mg/kg, i.p.) or aripiprazole (1mg/kg, i.p.), which have binding affinities to 5-HT(1A, 2A, 2B) and (2C) receptors decreased food intake in C57BL/6N mice with concomitant increase of hypothalamic histamine release. However, a selective D(2)-antagonist, haloperidol (0.5mg/kg, i.p.), did not have effects on food intake or histamine release. Furthermore, in histamine H(1) receptor-deficient mice, there was no reduction of food intake induced by atypical antipsychotics, although histamine release was increased. Moreover, selective 5-HT(2A)-antagonists, volinanserin (0.5, 1mg/kg, i.p.) and ketanserin (5, 10mg/kg, i.p.), significantly increased histamine release and 5-HT(2B/2C) -antagonist, SB206553 (2.5, 5mg/kg, i.p.), slightly increased it. On the contrary, 5-HT(1A) -selective antagonist, WAY100635 (1, 2mg/kg), did not affect the histaminergic tone. These findings suggest that serotonin tonically inhibits histamine release via 5-HT(2) receptors and that antipsychotics enhance the release of hypothalamic histamine by blockade of 5-HT(2) receptors resulting in anorexia via the H(1) receptor.

  14. The HPA and immune axes in stress: the involvement of the serotonergic system.

    Science.gov (United States)

    Leonard, B E

    2005-10-01

    The impact of acute and chronic stress on the hypothalamic-pituitary-adrenal (HPA) axis is reviewed and evidence presented that corticotrophin releasing factor (CRF) is the stress neurotransmitter which plays an important role in the activation of the central sympathetic and serotonergic systems. The activity of CRF is expressed through specific receptors (CRF 1 and 2) that are antagonistic in their actions and widely distributed in the limbic regions of the brain, as well as in the hypothalamus, and on immune cells. The mechanism whereby chronic stress, via the CRF induced activation of the dorsal raphe nucleus, can induce a change in the serotonergic system, involves an increase in the 5HT2A and a decrease in the 5HT1A receptor mediated function. Such changes contribute to the onset of anxiety and depression. In addition, the hypersecretion of glucocorticoids that is associated with chronic stress and depression desensitises the central glucocorticoid receptors to the negative feedback inhibition of the HPA axis. This indirectly results in the further activation of the HPA axis. The rise in pro-inflammatory cytokines that usually accompanies the chronic stress response results in a further stimulation of the HPA axis thereby adding to the stress response. While CRF would appear to play a pivotal role, evidence is provided that simultaneous changes in the serotonergic and noradrenergic systems, combined with the activation of peripheral and central macrophages that increase the pro-inflammatory cytokine concentrations in the brain and blood, also play a critical role in predisposing to anxiety and depression. Neurodegenerative changes in the brain that frequently occur in the elderly patient with major depression, could result from the activation of indoleaminedioxygenase (IDO), a widely distributed enzyme that converts tryptophan via the kynenine pathway to for the neurotoxic end product quinolinic acid. PMID:16459240

  15. An animal model of schizophrenia based on chronic LSD administration: old idea, new results.

    Science.gov (United States)

    Marona-Lewicka, Danuta; Nichols, Charles D; Nichols, David E

    2011-09-01

    Many people who take LSD experience a second temporal phase of LSD intoxication that is qualitatively different, and was described by Daniel Freedman as "clearly a paranoid state." We have previously shown that the discriminative stimulus effects of LSD in rats also occur in two temporal phases, with initial effects mediated by activation of 5-HT(2A) receptors (LSD30), and the later temporal phase mediated by dopamine D2-like receptors (LSD90). Surprisingly, we have now found that non-competitive NMDA antagonists produced full substitution in LSD90 rats, but only in older animals, whereas in LSD30, or in younger animals, these drugs did not mimic LSD. Chronic administration of low doses of LSD (>3 months, 0.16 mg/kg every other day) induces a behavioral state characterized by hyperactivity and hyperirritability, increased locomotor activity, anhedonia, and impairment in social interaction that persists at the same magnitude for at least three months after cessation of LSD treatment. These behaviors, which closely resemble those associated with psychosis in humans, are not induced by withdrawal from LSD; rather, they are the result of neuroadaptive changes occurring in the brain during the chronic administration of LSD. These persistent behaviors are transiently reversed by haloperidol and olanzapine, but are insensitive to MDL-100907. Gene expression analysis data show that chronic LSD treatment produced significant changes in multiple neurotransmitter system-related genes, including those for serotonin and dopamine. Thus, we propose that chronic treatment of rats with low doses of LSD can serve as a new animal model of psychosis that may mimic the development and progression of schizophrenia, as well as model the established disease better than current acute drug administration models utilizing amphetamine or NMDA antagonists such as PCP.

  16. Acute Effects of Lysergic Acid Diethylamide on Circulating Steroid Levels in Healthy Subjects.

    Science.gov (United States)

    Strajhar, P; Schmid, Y; Liakoni, E; Dolder, P C; Rentsch, K M; Kratschmar, D V; Odermatt, A; Liechti, M E

    2016-03-01

    Lysergic acid diethylamide (LSD) is a serotonin 5-hydroxytryptamine-2A (5-HT2A ) receptor agonist that is used recreationally worldwide. Interest in LSD research in humans waned after the 1970s, although the use of LSD in psychiatric research and practice has recently gained increasing attention. LSD produces pronounced acute psychedelic effects, although its influence on plasma steroid levels over time has not yet been characterised in humans. The effects of LSD (200 μg) or placebo on plasma steroid levels were investigated in 16 healthy subjects using a randomised, double-blind, placebo-controlled, cross-over study design. Plasma concentration-time profiles were determined for 15 steroids using liquid-chromatography tandem mass-spectrometry. LSD increased plasma concentrations of the glucocorticoids cortisol, cortisone, corticosterone and 11-dehydrocorticosterone compared to placebo. The mean maximum concentration of LSD was reached at 1.7 h. Mean peak psychedelic effects were reached at 2.4 h, with significant alterations in mental state from 0.5 h to > 10 h. Mean maximal concentrations of cortisol and corticosterone were reached at 2.5 h and 1.9 h, and significant elevations were observed 1.5-6 h and 1-3 h after drug administration, respectively. LSD also significantly increased plasma concentrations of the androgen dehydroepiandrosterone but not other androgens, progestogens or mineralocorticoids compared to placebo. A close relationship was found between plasma LSD concentrations and changes in plasma cortisol and corticosterone and the psychotropic response to LSD, and no clockwise hysteresis was observed. In conclusion, LSD produces significant acute effects on circulating steroids, especially glucocorticoids. LSD-induced changes in circulating glucocorticoids were associated with plasma LSD concentrations over time and showed no acute pharmacological tolerance.

  17. Possible contribution of epigenetic changes in the development of schizophrenia-like behavior in vasopressin-deficient Brattleboro rats.

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    Demeter, Kornél; Török, Bibiána; Fodor, Anna; Varga, János; Ferenczi, Szilamér; Kovács, Krisztina J; Eszik, Ildikó; Szegedi, Viktor; Zelena, Dóra

    2016-03-01

    Schizophrenia-like symptoms were detected in vasopressin-deficient (di/di) Brattleboro rats, and it was also suggested that schizophrenia might have an epigenetic component. We aimed to clarify if epigenetic changes contribute to schizophrenia-like behavior of this strain. Behavioral (locomotion by telemetry, cognition by novel object recognition, social recognition and social avoidance test, attention by pre-pulse inhibition) and epigenetic differences were compared between wild type and di/di animals. DNA methyltransferase1 (DNMT1), DNMT3a, as well as COMT, GAD, VGLUT1, 5HT2A, BDNF mRNA levels in prefrontal brain region and hippocampus were studied by qRT-PCR. Histone3 (H3) and H4 acetylation (Ac) were studied by western-blot followed by region specific examination of H3 lysine9 (K9) acetylation by immunohistochemistry. Impaired cognitive, social and attention behavior of di/di rats confirmed schizophrenia-like symptoms in our local colony. The pan-AcH3 immunoreactivity was lower in prefrontal region and elevated in the hippocampus of di/di animals. We found lower immunopositive cell number in the dorsal peduncular prefrontal cortex and the ventral lateral septum and increased AcH3K9 immunoreactivity in CA1 region of di/di animals. There were no major significant alterations in the studied mRNA levels. We confirmed that Brattleboro rat is a good preclinical model of schizophrenia. Its schizophrenia-like behavioral alteration was accompanied by changes in H3 acetylation in the prefrontal region and hippocampus. This may contribute to disturbances of many schizophrenia-related substances leading to development of schizophrenia-like symptoms. Our studies confirmed that not a single gene, rather fine changes in an array of molecules are responsible for the majority of schizophrenia cases. PMID:26704217

  18. Acute Effects of Lysergic Acid Diethylamide on Circulating Steroid Levels in Healthy Subjects.

    Science.gov (United States)

    Strajhar, P; Schmid, Y; Liakoni, E; Dolder, P C; Rentsch, K M; Kratschmar, D V; Odermatt, A; Liechti, M E

    2016-03-01

    Lysergic acid diethylamide (LSD) is a serotonin 5-hydroxytryptamine-2A (5-HT2A ) receptor agonist that is used recreationally worldwide. Interest in LSD research in humans waned after the 1970s, although the use of LSD in psychiatric research and practice has recently gained increasing attention. LSD produces pronounced acute psychedelic effects, although its influence on plasma steroid levels over time has not yet been characterised in humans. The effects of LSD (200 μg) or placebo on plasma steroid levels were investigated in 16 healthy subjects using a randomised, double-blind, placebo-controlled, cross-over study design. Plasma concentration-time profiles were determined for 15 steroids using liquid-chromatography tandem mass-spectrometry. LSD increased plasma concentrations of the glucocorticoids cortisol, cortisone, corticosterone and 11-dehydrocorticosterone compared to placebo. The mean maximum concentration of LSD was reached at 1.7 h. Mean peak psychedelic effects were reached at 2.4 h, with significant alterations in mental state from 0.5 h to > 10 h. Mean maximal concentrations of cortisol and corticosterone were reached at 2.5 h and 1.9 h, and significant elevations were observed 1.5-6 h and 1-3 h after drug administration, respectively. LSD also significantly increased plasma concentrations of the androgen dehydroepiandrosterone but not other androgens, progestogens or mineralocorticoids compared to placebo. A close relationship was found between plasma LSD concentrations and changes in plasma cortisol and corticosterone and the psychotropic response to LSD, and no clockwise hysteresis was observed. In conclusion, LSD produces significant acute effects on circulating steroids, especially glucocorticoids. LSD-induced changes in circulating glucocorticoids were associated with plasma LSD concentrations over time and showed no acute pharmacological tolerance. PMID:26849997

  19. Increased Global Functional Connectivity Correlates with LSD-Induced Ego Dissolution.

    Science.gov (United States)

    Tagliazucchi, Enzo; Roseman, Leor; Kaelen, Mendel; Orban, Csaba; Muthukumaraswamy, Suresh D; Murphy, Kevin; Laufs, Helmut; Leech, Robert; McGonigle, John; Crossley, Nicolas; Bullmore, Edward; Williams, Tim; Bolstridge, Mark; Feilding, Amanda; Nutt, David J; Carhart-Harris, Robin

    2016-04-25

    Lysergic acid diethylamide (LSD) is a non-selective serotonin-receptor agonist that was first synthesized in 1938 and identified as (potently) psychoactive in 1943. Psychedelics have been used by indigenous cultures for millennia [1]; however, because of LSD's unique potency and the timing of its discovery (coinciding with a period of major discovery in psychopharmacology), it is generally regarded as the quintessential contemporary psychedelic [2]. LSD has profound modulatory effects on consciousness and was used extensively in psychological research and psychiatric practice in the 1950s and 1960s [3]. In spite of this, however, there have been no modern human imaging studies of its acute effects on the brain. Here we studied the effects of LSD on intrinsic functional connectivity within the human brain using fMRI. High-level association cortices (partially overlapping with the default-mode, salience, and frontoparietal attention networks) and the thalamus showed increased global connectivity under the drug. The cortical areas showing increased global connectivity overlapped significantly with a map of serotonin 2A (5-HT2A) receptor densities (the key site of action of psychedelic drugs [4]). LSD also increased global integration by inflating the level of communication between normally distinct brain networks. The increase in global connectivity observed under LSD correlated with subjective reports of "ego dissolution." The present results provide the first evidence that LSD selectively expands global connectivity in the brain, compromising the brain's modular and "rich-club" organization and, simultaneously, the perceptual boundaries between the self and the environment. PMID:27085214

  20. Substituted methcathinones differ in transporter and receptor interactions

    Science.gov (United States)

    Eshleman, Amy J; Wolfrum, Katherine M; Hatfield, Meagan G; Johnson, Robert A; Murphy, Kevin V; Janowsky, Aaron

    2013-01-01

    The use of synthetic methcathinones, components of “bath salts,” is a world-wide health concern. These compounds, structurally similar to methamphetamine (METH) and 3,4-methylendioxymethamphetamine (MDMA), cause tachycardia, hallucinations and psychosis. We hypothesized that these potentially neurotoxic and abused compounds display differences in their transporter and receptor interactions as compared to amphetamine counterparts. 3,4-Methylenedioxypyrovalerone and naphyrone had high affinity for radioligand binding sites on recombinant human dopamine (hDAT), serotonin (hSERT) and norepinephrine (hNET) transporters, potently inhibited [3H]neurotransmitter uptake, and, like cocaine, did not induce transporter-mediated release. Butylone was a lower affinity uptake inhibitor. In contrast, 4-fluoromethcathinone, mephedrone and methylone had higher inhibitory potency at uptake compared to binding and generally induced release of preloaded [3H]neurotransmitter from hDAT, hSERT and hNET (highest potency at hNET), and thus are transporter substrates, similar to METH and MDMA. At hNET, 4-fluoromethcathinone was a more efficacious releaser than METH. These substituted methcathinones had low uptake inhibitory potency and low efficacy at inducing release via human vesicular monoamine transporters (hVMAT2). These compounds were low potency 1) h5-HT1A receptor partial agonists, 2) h5-HT2A receptor antagonists, 3) weak h5-HT2C receptor antagonists. This is the first report on aspects of substituted methcathinone efficacies at serotonin (5-HT) receptors and in superfusion release assays. Additionally, the drugs had no affinity for dopamine receptors, and high- mid-micromolar affinity for hSigma1 receptors. Thus, direct interactions with hVMAT2 and serotonin, dopamine, and hSigma1 receptors may not explain psychoactive effects. The primary mechanisms of action may be as inhibitors or substrates of DAT, SERT and NET. PMID:23583454

  1. Flibanserin: a serendipitous story

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    Melvin George

    2016-08-01

    Full Text Available Female sexual disorders are increasingly being recognized in the population and hypoactive sexual desire disorder (HSDD is one of the commonest sexual disorders among females. The prevalence of the disease varies between 10-20% in the Caucasian population. Testosterone is the only treatment that is approved by the European Medical Agency. Flibanserin is a drug that has been approved by the US FDA for HSDD among pre-menopausal women in 2015. Flibanserin is a 5-HT1A receptor agonist and 5-HT2A receptor antagonist that rebalances the neural circuitry involved in processing sexual desire by reducing serotonin activity and enhancing dopamine and epinephrine activity. The efficacy of the drug was confirmed in three pivotal randomized placebo control trials in premenopausal women who consumed the drug for 24 weeks. There was a significant improvement in the number of sexually satisfying events. The most common safety concerns for flibanserin as seen in clinical trials were somnolence, hypotension and syncope. The drug is prescribed at a dose of 100 mg once daily at bed time. The marginal efficacy of the drug coupled with other safety concerns, such as hypo-tensions have given room for much criticism over the drug's approval by the FDA. Nevertheless, on a positive note the serendipitous discovery of flibanserin and its repurposing for HSDD is a compelling narrative in its drug development history. It remains to be seen if the long term safety of the molecule and the efficacy of the molecule in non-trial settings could make it an attractive pharmaco-therapeutic option for HSDD. [Int J Basic Clin Pharmacol 2016; 5(4.000: 1156-1158

  2. Control of sensory neuron excitability by serotonin involves 5HT2C receptors and Ca(2+)-activated chloride channels.

    Science.gov (United States)

    Salzer, Isabella; Gantumur, Enkhbileg; Yousuf, Arsalan; Boehm, Stefan

    2016-11-01

    Serotonin (5HT) is a constituent of the so-called "inflammatory soup" that sensitizes nociceptors during inflammation. Nevertheless, receptors and signaling mechanisms that mediate an excitation of dorsal root ganglion (DRG) neurons by 5HT remained controversial. Therefore, capsaicin-sensitive nociceptive neurons dissociated from rat DRGs were used to investigate effects of 5HT on membrane excitability and currents through ligand- as well as voltage-gated ion channels. In 58% of the neurons tested, 5HT increased action potential firing, an effect that was abolished by the 5HT2 receptor antagonist ritanserin, but not by the 5HT3 antagonist tropisetron. Unlike other algogenic mediators, such as PGE2 and bradykinin, 5HT did not affect currents through TTX-resistant Na(+) channels or Kv7 K(+) channels. In all neurons investigated, 5HT potentiated capsaicin-evoked currents through TRPV1 channels, an effect that was attenuated by antagonists at 5HT2A (4 F 4 PP), 5HT2B (SB 204741), as well as 5HT2C (RS 102221) receptors. 5HT triggered slowly arising inward Cl(-) currents in 53% of the neurons. This effect was antagonized by the 5HT2C receptor blocker only, and the current was prevented by an inhibitor of Ca(2+)-activated chloride channels (CaCC). The 5HT-induced increase in action potential firing was also abolished by this CaCC blocker and by the TRPV1 inhibitor capsazepine. Amongst the subtype selective 5HT2 antagonists, only RS 102221 (5HT2C-selectively) counteracted the rise in action potential firing elicited by 5HT. These results show that 5HT excites DRG neurons mainly via 5HT2C receptors which concomitantly mediate a sensitization of TRPV1 channels and an opening of CaCCs.

  3. Neurobehavioral and genotoxic parameters of antipsychotic agent aripiprazole in mice

    Institute of Scientific and Technical Information of China (English)

    Jaqueline Nascimento PICADA; Viviane Minuzzo PONTES; Patrícia PEREIRA; Bruna de Jesus Neto DOS SANTOS; Franciele CELSO; Jéssica Dias MONTEIRO; Kelly Morais DA ROSA; Leandro Rosa CAMACHO; Luciana Rodrigues VIEIRA; Taís Madelon FREITAS; Tatiana Grasiela DASILVA

    2011-01-01

    Aim:Aripiprazole is an antipsychotic agent to treat schizophrenia,which acts through dopamine D2 partial agonism,serotonin 5-HT1A partial agonism and 5-HT2A antagonism.This study was designed to evaluate the neurobehavioral effects and genotoxic/mutagenic activities of the agent,as well as its effects on lipoperoxidation.Methods:Open field and inhibitory avoidance tasks were used.Thirty min before performing the behavioral tasks,adult male CF-1 mice were administered aripiprazole (1,3 or 10 mg/kg,ip) once for the acute treatment,or the same doses for 5 d for the subchronic treatment.Genotoxic effects were assessed using comet assay in the blood and brain tissues.Mutagenic effects were evaluated using bone marrow micronucleus test.Lipoperoxidation was assessed with thiobarbituric acid reactive substances (TBARS).Results:Acute and subchronic treatments significantly decreased the number of crossing and rearing in the open field task.Acute treatment significantly increased the step-down latency for both the short- and long-term memory in the inhibitory avoidance task.Subchronic treatments with aripiprazole (3 and 10 mg/kg) caused significant DNA strain-break damage in peripheral blood but not in the brain.Mutagenic effect was not detected in the acute and subchronic treatments.Nor TBARS levels in the liver were affected.Conclusion:Aripiprazole improved memory,but could impair motor activities in mice.The drug increased DNA damage in blood,but did not show mutagenic effects,suggesting that it might affect long-term genomic stability.

  4. Profile of aripiprazole in the treatment of bipolar disorder in children and adolescents

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    Kirino E

    2014-11-01

    Full Text Available Eiji Kirino1–3 1Department of Psychiatry, Juntendo University School of Medicine, 2Department of Psychiatry, Juntendo University Shizuoka Hospital, 3Juntendo Institute of Mental Health, Shizuoka, Japan Abstract: Bipolar disorder is a pernicious illness. Compared with the later-onset form, early onset bipolar disorder is associated with worse psychosocial outcomes, and is characterized by rapid cycling and increased risks of substance abuse and suicide attempts. Controlling mood episodes and preventing relapse in this group of pediatric patients requires careful treatment. Here, we review the effectiveness of aripiprazole for bipolar disorder in children and adolescents, with discussion of this drug's unique pharmacological profile and various clinical study outcomes. Aripiprazole acts as a serotonin 5-HT2A receptor antagonist, as well as a partial agonist of the serotonin 5-HT1A and dopamine D2 receptors. It can be safely used in children and adolescents, as it is highly tolerated and shows lower rates of the side effects typically observed with other antipsychotic drugs, including sedation, weight gain, hyperprolactinemia, and extrapyramidal syndrome. The presently reviewed randomized controlled trials (RCTs and non-RCTs generally reported aripiprazole to be effective and well-tolerated in children and adolescents with bipolar disorder. However, due to the limited number of RCTs, the present conclusions must be evaluated cautiously. Furthermore, aripiprazole cannot yet be considered a preferred treatment for children and adolescents with bipolar disorder, as there is not yet evidence that aripiprazole shows greater efficacy compared to other second-generation antipsychotics. Additional data are needed from future head-to-head comparison studies. Keywords: child, mania, mixed state

  5. Serotonin differentially modulates excitatory and inhibitory synaptic inputs to putative sleep-promoting neurons of the ventrolateral preoptic nucleus.

    Science.gov (United States)

    Sangare, Aude; Dubourget, Romain; Geoffroy, Hélène; Gallopin, Thierry; Rancillac, Armelle

    2016-10-01

    The role of serotonin (5-HT) in sleep-wake regulation has been a subject of intense debate and remains incompletely understood. In the ventrolateral preoptic nucleus (VLPO), the main structure that triggers non-rapid eye movement (NREM) sleep, putative sleep-promoting (PSP) neurons were shown ex vivo to be either inhibited (Type-1) or excited (Type-2) by 5-HT application. To determine the complex action of this neurotransmitter on PSP neurons, we recorded spontaneous and miniature excitatory and inhibitory postsynaptic currents (sEPSCs, sIPSCs, mEPSCs and mIPSCs) in response to bath application of 5-HT. We established in mouse acute VLPO slices that 5-HT reduces spontaneous and miniature EPSC and IPSC frequencies to Type-1 neurons, whereas 5-HT selectively increases sIPSC and mIPSC frequencies to Type-2 VLPO neurons. We further determined that Type-1 neurons display a lower action potential threshold and a smaller soma size than Type-2 neurons. Finally, single-cell RT-PCR designed to identify the 13 serotonergic receptor subtypes revealed the specific mRNA expression of the 5-HT1A,B,D,F receptors by Type-1 neurons. Furthermore, the 5-HT2A-C,4,7 receptors were found to be equivalently expressed by both neuronal types. Altogether, our results establish that the excitatory and inhibitory inputs to Type-1 and Type-2 VLPO PSP neurons are differentially regulated by 5-HT. Electrophysiological, morphological and molecular differences were also identified between these two neuronal types. Our results provide new insights regarding the orchestration of sleep regulation by 5-HT release, and strongly suggest that Type-2 neurons could play a permissive role, whereas Type-1 neurons could have an executive role in sleep induction and maintenance. PMID:27238836

  6. AVN-101: A Multi-Target Drug Candidate for the Treatment of CNS Disorders.

    Science.gov (United States)

    Ivachtchenko, Alexandre V; Lavrovsky, Yan; Okun, Ilya

    2016-05-25

    Lack of efficacy of many new highly selective and specific drug candidates in treating diseases with poorly understood or complex etiology, as are many of central nervous system (CNS) diseases, encouraged an idea of developing multi-modal (multi-targeted) drugs. In this manuscript, we describe molecular pharmacology, in vitro ADME, pharmacokinetics in animals and humans (part of the Phase I clinical studies), bio-distribution, bioavailability, in vivo efficacy, and safety profile of the multimodal drug candidate, AVN-101. We have carried out development of a next generation drug candidate with a multi-targeted mechanism of action, to treat CNS disorders. AVN-101 is a very potent 5-HT7 receptor antagonist (Ki = 153 pM), with slightly lesser potency toward 5-HT6, 5-HT2A, and 5HT-2C receptors (Ki = 1.2-2.0 nM). AVN-101 also exhibits a rather high affinity toward histamine H1 (Ki = 0.58 nM) and adrenergic α2A, α2B, and α2C (Ki = 0.41-3.6 nM) receptors. AVN-101 shows a good oral bioavailability and facilitated brain-blood barrier permeability, low toxicity, and reasonable efficacy in animal models of CNS diseases. The Phase I clinical study indicates the AVN-101 to be well tolerated when taken orally at doses of up to 20 mg daily. It does not dramatically influence plasma and urine biochemistry, nor does it prolong QT ECG interval, thus indicating low safety concerns. The primary therapeutic area for AVN-101 to be tested in clinical trials would be Alzheimer's disease. However, due to its anxiolytic and anti-depressive activities, there is a strong rational for it to also be studied in such diseases as general anxiety disorders, depression, schizophrenia, and multiple sclerosis. PMID:27232215

  7. Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats

    Science.gov (United States)

    Favaro, Vanessa Manchim; Yonamine, Maurício; Soares, Juliana Carlota Kramer; Oliveira, Maria Gabriela Menezes

    2015-01-01

    Ayahuasca is a hallucinogenic beverage that combines the action of the 5-HT2A/2C agonist N,N-dimethyltryptamine (DMT) from Psychotria viridis with the monoamine oxidase inhibitors (MAOIs) induced by beta-carbonyls from Banisteriopsis caapi. Previous investigations have highlighted the involvement of ayahuasca with the activation of brain regions known to be involved with episodic memory, contextual associations and emotional processing after ayahuasca ingestion. Moreover long term users show better performance in neuropsychological tests when tested in off-drug condition. This study evaluated the effects of long-term administration of ayahuasca on Morris water maze (MWM), fear conditioning and elevated plus maze (EPM) performance in rats. Behavior tests started 48h after the end of treatment. Freeze-dried ayahuasca doses of 120, 240 and 480 mg/kg were used, with water as the control. Long-term administration consisted of a daily oral dose for 30 days by gavage. The behavioral data indicated that long-term ayahuasca administration did not affect the performance of animals in MWM and EPM tasks. However the dose of 120 mg/kg increased the contextual conditioned fear response for both background and foreground fear conditioning. The tone conditioned response was not affected after long-term administration. In addition, the increase in the contextual fear response was maintained during the repeated sessions several weeks after training. Taken together, these data showed that long-term ayahuasca administration in rats can interfere with the contextual association of emotional events, which is in agreement with the fact that the beverage activates brain areas related to these processes. PMID:26716991

  8. Selective serotonergic excitation of callosal projection neurons

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    Daniel eAvesar

    2012-03-01

    Full Text Available Serotonin (5-HT acting as a neurotransmitter in the cerebral cortex is critical for cognitive function, yet how 5-HT regulates information processing in cortical circuits is not well understood. We tested the serotonergic responsiveness of layer 5 pyramidal neurons (L5PNs of the mouse medial prefrontal cortex (mPFC, and found 3 distinct response types: long-lasting 5-HT1A (1A receptor-dependent inhibitory responses (84% of L5PNs, 5-HT2A (2A receptor-dependent excitatory responses (9%, and biphasic responses in which 2A-dependent excitation followed brief inhibition (5%. Relative to 5-HT-inhibited neurons, those excited by 5-HT had physiological properties characteristic of callosal/commissural (COM neurons that project to the contralateral cortex. We tested whether serotonergic responses in cortical pyramidal neurons are correlated with their axonal projection pattern using retrograde fluorescent labeling of COM and corticopontine-projecting (CPn neurons. 5-HT generated excitatory or biphasic responses in all 5-HT-responsive layer 5 COM neurons. Conversely, CPn neurons were universally inhibited by 5-HT. Serotonergic excitation of COM neurons was blocked by the 2A antagonist MDL 11939, while serotonergic inhibition of CPn neurons was blocked by the 1A antagonist WAY 100635, confirming a role for these two receptor subtypes in regulating pyramidal neuron activity. Selective serotonergic excitation of COM neurons was not layer-specific, as COM neurons in layer 2/3 were also selectively excited by 5-HT relative to their non-labeled pyramidal neuron neighbors. Because neocortical 2A receptors are implicated in the etiology and pathophysiology of schizophrenia, we propose that COM neurons may represent a novel cellular target for intervention in psychiatric disease.

  9. Personality, psychopathology, life attitudes and neuropsychological performance among ritual users of Ayahuasca: a longitudinal study.

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    José Carlos Bouso

    Full Text Available Ayahuasca is an Amazonian psychoactive plant beverage containing the serotonergic 5-HT(2A agonist N,N-dimethyltryptamine (DMT and monoamine oxidase-inhibiting alkaloids (harmine, harmaline and tetrahydroharmine that render it orally active. Ayahuasca ingestion is a central feature in several Brazilian syncretic churches that have expanded their activities to urban Brazil, Europe and North America. Members of these groups typically ingest ayahuasca at least twice per month. Prior research has shown that acute ayahuasca increases blood flow in prefrontal and temporal brain regions and that it elicits intense modifications in thought processes, perception and emotion. However, regular ayahuasca use does not seem to induce the pattern of addiction-related problems that characterize drugs of abuse. To study the impact of repeated ayahuasca use on general psychological well-being, mental health and cognition, here we assessed personality, psychopathology, life attitudes and neuropsychological performance in regular ayahuasca users (n = 127 and controls (n = 115 at baseline and 1 year later. Controls were actively participating in non-ayahuasca religions. Users showed higher Reward Dependence and Self-Transcendence and lower Harm Avoidance and Self-Directedness. They scored significantly lower on all psychopathology measures, showed better performance on the Stroop test, the Wisconsin Card Sorting Test and the Letter-Number Sequencing task from the WAIS-III, and better scores on the Frontal Systems Behavior Scale. Analysis of life attitudes showed higher scores on the Spiritual Orientation Inventory, the Purpose in Life Test and the Psychosocial Well-Being test. Despite the lower number of participants available at follow-up, overall differences with controls were maintained one year later. In conclusion, we found no evidence of psychological maladjustment, mental health deterioration or cognitive impairment in the ayahuasca-using group.

  10. The natural hallucinogen 5-MeO-DMT, component of Ayahuasca, disrupts cortical function in rats: reversal by antipsychotic drugs.

    Science.gov (United States)

    Riga, Maurizio S; Soria, Guadalupe; Tudela, Raúl; Artigas, Francesc; Celada, Pau

    2014-08-01

    5-Methoxy-N,N-dimethyltryptamine (5-MeO-DMT) is a natural hallucinogen component of Ayahuasca, an Amazonian beverage traditionally used for ritual, religious and healing purposes that is being increasingly used for recreational purposes in US and Europe. 5MeO-DMT is of potential interest for schizophrenia research owing to its hallucinogenic properties. Two other psychotomimetic agents, phencyclidine and 2,5-dimethoxy-4-iodo-phenylisopropylamine (DOI), markedly disrupt neuronal activity and reduce the power of low frequency cortical oscillations (DMT on cortical function and its potential reversal by antipsychotic drugs. Moreover, regional brain activity was assessed by blood-oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI). 5-MeO-DMT disrupted mPFC activity, increasing and decreasing the discharge of 51 and 35% of the recorded pyramidal neurons, and reducing (-31%) the power of LFCO. The latter effect depended on 5-HT1A and 5-HT2A receptor activation and was reversed by haloperidol, clozapine, risperidone, and the mGlu2/3 agonist LY379268. Likewise, 5-MeO-DMT decreased BOLD responses in visual cortex (V1) and mPFC. The disruption of cortical activity induced by 5-MeO-DMT resembles that produced by phencyclidine and DOI. This, together with the reversal by antipsychotic drugs, suggests that the observed cortical alterations are related to the psychotomimetic action of 5-MeO-DMT. Overall, the present model may help to understand the neurobiological basis of hallucinations and to identify new targets in antipsychotic drug development.

  11. Development of a mechanism-based pharmacokinetic/pharmacodynamic model to characterize the thermoregulatory effects of serotonergic drugs in mice

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    Xi-Ling Jiang

    2016-09-01

    Full Text Available We have shown recently that concurrent harmaline, a monoamine oxidase-A inhibitor (MAOI, potentiates serotonin (5-HT receptor agonist 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT-induced hyperthermia. The objective of this study was to develop an integrated pharmacokinetic/pharmacodynamic (PK/PD model to characterize and predict the thermoregulatory effects of such serotonergic drugs in mice. Physiological thermoregulation was described by a mechanism-based indirect-response model with adaptive feedback control. Harmaline-induced hypothermia and 5-MeO-DMT–elicited hyperthermia were attributable to the loss of heat through the activation of 5-HT1A receptor and thermogenesis via the stimulation of 5-HT2A receptor, respectively. Thus serotonergic 5-MeO-DMT–induced hyperthermia was readily distinguished from handling/injection stress-provoked hyperthermic effects. This PK/PD model was able to simultaneously describe all experimental data including the impact of drug-metabolizing enzyme status on 5-MeO-DMT and harmaline PK properties, and drug- and stress-induced simple hypo/hyperthermic and complex biphasic effects. Furthermore, the modeling results revealed a 4-fold decrease of apparent SC50 value (1.88–0.496 µmol/L for 5-MeO-DMT when harmaline was co-administered, providing a quantitative assessment for the impact of concurrent MAOI harmaline on 5-MeO-DMT–induced hyperthermia. In addition, the hyperpyrexia caused by toxic dose combinations of harmaline and 5-MeO-DMT were linked to the increased systemic exposure to harmaline rather than 5-MeO-DMT, although the body temperature profiles were mispredicted by the model. The results indicate that current PK/PD model may be used as a new conceptual framework to define the impact of serotonergic agents and stress factors on thermoregulation.

  12. Echinocystic acid reduces reserpine-induced pain/depression dyad in mice.

    Science.gov (United States)

    Li, Shuo; Han, Jing; Wang, Dong-Sheng; Feng, Bin; Deng, Ya-Ting; Wang, Xin-Shang; Yang, Qi; Zhao, Ming-Gao

    2016-04-01

    Chronic pain has consistently been correlated with depression. Echinocystic acid (EA), a natural triterpone enriched in various herbs and used for medicinal purpose in many Asian countries, exhibits anti-inflammatory and analgesic activities. However, little is known the effects of EA on the depression. In present study, we investigated the anti-depression activities in the mouse model of reserpine-induced pain-depression dyad. Reserpine (1 mg/kg subcutaneously daily for 3 days) caused significant depression-like behaviors and pain sensation. Subsequent treatment of EA (5 mg/kg intragastrically daily for 5 days) attenuated the reserpine-induced pain/depression dyad as shown by the increase of pain threshold and the behaviors in forced swimming test, tail suspension test, and open field test. Furthermore, treatment of EA reversed the decrease of biogenic amines (norepinephrine, dopamine, and serotonin) in the brain region of hippocampus, a structure involved in the formation of emotional disorders. Levels of serotonin receptor 5-HT1A were decreased and levels of 5-HT2A were increased in the reserpine-injected mice. Treatment of EA could restore the alterations of serotonin receptors. At the same time, the increase in GluN2B-containing NMDA receptors, p-GluA1-Ser831, PSD-95 and CaMKII were integrated with the increase in caspase-3 and iNOS levels in the hippocampus of the reserpine-injected mice. EA significantly reversed the changes of above proteins. However, EA did not affect the levels of GluN2A-containing NMDA receptors and the total levels of GluA1 and p-GluA1-Ser845. Our study provides strong evidence that EA attenuates reserpine-induced pain/depression dyad partially through regulating the biogenic amines levels and GluN2B receptors in the hippocampus. PMID:26729203

  13. Serotonin dependent masking of hippocampal sharp wave ripples.

    Science.gov (United States)

    ul Haq, Rizwan; Anderson, Marlene L; Hollnagel, Jan-Oliver; Worschech, Franziska; Sherkheli, Muhammad Azahr; Behrens, Christoph J; Heinemann, Uwe

    2016-02-01

    Sharp wave ripples (SPW-Rs) are thought to play an important role in memory consolidation. By rapid replay of previously stored information during slow wave sleep and consummatory behavior, they result from the formation of neural ensembles during a learning period. Serotonin (5-HT), suggested to be able to modify SPW-Rs, can affect many neurons simultaneously by volume transmission and alter network functions in an orchestrated fashion. In acute slices from dorsal hippocampus, SPW-Rs can be induced by repeated high frequency stimulation that induces long-lasting LTP. We used this model to study SPW-R appearance and modulation by 5-HT. Although stimulation in presence of 5-HT permitted LTP induction, SPW-Rs were "masked"--but appeared after 5-HT wash-out. This SPW-R masking was dose dependent with 100 nM 5-HT being sufficient--if the 5-HT re-uptake inhibitor citalopram was present. Fenfluramine, a serotonin releaser, could also mask SPW-Rs. Masking was due to 5-HT1A and 5-HT2A/C receptor activation. Neither membrane potential nor membrane conductance changes in pyramidal cells caused SPW-R blockade since both remained unaffected by combining 5-HT and citalopram. Moreover, 10 and 30 μM 5-HT mediated SPW-R masking preceded neuronal hyperpolarization and involved reduced presynaptic transmitter release. 5-HT, as well as a 5-HT1A agonist, augmented paired pulse facilitation and affected the coefficient of variance. Spontaneous SPW-Rs in mice hippocampal slices were also masked by 5-HT and fenfluramine. While neuronal ensembles can acquire long lasting LTP during higher 5-HT levels, lower 5-HT levels enable neural ensembles to replay previously stored information and thereby permit memory consolidation memory. PMID:26409781

  14. A Systematic Review of Plant-Derived Natural Compounds for Anxiety Disorders.

    Science.gov (United States)

    Farzaei, Mohammad Hosein; Bahramsoltani, Roodabeh; Rahimi, Roja; Abbasabadi, Faezeh; Abdollahi, Mohammad

    2016-01-01

    Anxiety disorders are the most common mental illnesses affecting human beings. They range from panic to generalized anxiety disorders upsetting the well-being and psychosocial performance of patients. Several conventional anxiolytic drugs are being used which in turn results in several adverse effects. Therefore, studies to find suitable safe medicines from natural sources are being conducted by researchers. The aim of the present study is to comprehensively review phytochemical compounds with well-established anxiolytic activities and their structure-activity relationships as well as neuropsychopharmacological aspects. Results showed that phytochemicals like; alkaloids, flavonoids, phenolic acids, lignans, cinnamates, terpenes and saponins possess anxiolytic effects in a wide range of animal models of anxiety. The involved mechanisms include interaction with γ-aminobutyric acid (GABA)A receptors at benzodiazepine (BZD) and non-BZD sites with various affinity to different subunits, serotonergic 5-hydrodytryptamine (5-HT)1A and 5-HT2A/C receptors, noradrenergic and dopaminergic systems, glycine and glutamate receptors, and κ-opioid receptor as well as cannabinoid (CB)1 and CB2 receptors. Phytochemicals also modulate the hypothalamo-pituitary-adrenal (HPA) axis, the levels of pro-inflammatory cytokines like interleukin (IL)-2, IL-6, IL-1β and tumor necrosis factor (TNF)-α, and improve brain derived neurotrophic factor (BDNF) levels. Transient receptor potential cation channel subfamily V (TRPV)3, nitric oxide cyclic guanosine monophosphate (NOcGMP) pathway and monoamine oxidase enzymes are other targets of phytochemicals with anxiolytic activity. Taking together, these phytochemicals may be considered as supplements to conventional anxiolytic therapies in order to improve efficacy and reduce adverse effects. Further preclinical and clinical studies are still needed in order to recognize the structure-activity relationships, metabolism, absorption, and

  15. Antidepressant Effects of a Single Dose of Ayahuasca in Patients With Recurrent Depression: A SPECT Study.

    Science.gov (United States)

    Sanches, Rafael Faria; de Lima Osório, Flávia; Dos Santos, Rafael G; Macedo, Ligia R H; Maia-de-Oliveira, João Paulo; Wichert-Ana, Lauro; de Araujo, Draulio Barros; Riba, Jordi; Crippa, José Alexandre S; Hallak, Jaime E C

    2016-02-01

    Ayahuasca is an Amazonian botanical hallucinogenic brew which contains dimethyltryptamine, a 5-HT2A receptor agonist, and harmine, a monoamine-oxidase A inhibitor. Our group recently reported that ayahuasca administration was associated with fast-acting antidepressive effects in 6 depressive patients. The objective of the present work was to assess the antidepressive potentials of ayahuasca in a bigger sample and to investigate its effects on regional cerebral blood flow. In an open-label trial conducted in an inpatient psychiatric unit, 17 patients with recurrent depression received an oral dose of ayahuasca (2.2 mL/kg) and were evaluated with the Hamilton Rating Scale for Depression, the Montgomery-Åsberg Depression Rating Scale, the Brief Psychiatric Rating Scale, the Young Mania Rating Scale, and the Clinician Administered Dissociative States Scale during acute ayahuasca effects and 1, 7, 14, and 21 days after drug intake. Blood perfusion was assessed eight hours after drug administration by means of single photon emission tomography. Ayahuasca administration was associated with increased psychoactivity (Clinician Administered Dissociative States Scale) and significant score decreases in depression-related scales (Hamilton Rating Scale for Depression, Montgomery-Åsberg Depression Rating Scale, Brief Psychiatric Rating Scale) from 80 minutes to day 21. Increased blood perfusion in the left nucleus accumbens, right insula and left subgenual area, brain regions implicated in the regulation of mood and emotions, were observed after ayahuasca intake. Ayahuasca was well tolerated. Vomiting was the only adverse effect recorded, being reported by 47% of the volunteers. Our results suggest that ayahuasca may have fast-acting and sustained antidepressive properties. These results should be replicated in randomized, double-blind, placebo-controlled trials. PMID:26650973

  16. Autonomic, neuroendocrine, and immunological effects of ayahuasca: a comparative study with d-amphetamine.

    Science.gov (United States)

    Dos Santos, Rafael G; Valle, Marta; Bouso, José Carlos; Nomdedéu, Josep F; Rodríguez-Espinosa, José; McIlhenny, Ethan H; Barker, Steven A; Barbanoj, Manel J; Riba, Jordi

    2011-12-01

    Ayahuasca is an Amazonian psychotropic plant tea combining the 5-HT2A agonist N,N-dimethyltryptamine (DMT) and monoamine oxidase-inhibiting β-carboline alkaloids that render DMT orally active. The tea, obtained from Banisteriopsis caapi and Psychotria viridis, has traditionally been used for religious, ritual, and medicinal purposes by the indigenous peoples of the region. More recently, the syncretistic religious use of ayahuasca has expanded to the United States and Europe. Here we conducted a double-blind randomized crossover clinical trial to investigate the physiological impact of ayahuasca in terms of autonomic, neuroendocrine, and immunomodulatory effects. An oral dose of encapsulated freeze-dried ayahuasca (1.0 mg DMT/kg body weight) was compared versus a placebo and versus a positive control (20 mg d-amphetamine) in a group of 10 healthy volunteers. Ayahuasca led to measurable DMT plasma levels and distinct subjective and neurophysiological effects that were absent after amphetamine. Both drugs increased pupillary diameter, with ayahuasca showing milder effects. Prolactin levels were significantly increased by ayahuasca but not by amphetamine, and cortisol was increased by both, with ayahuasca leading to the higher peak values. Ayahuasca and amphetamine induced similar time-dependent modifications in lymphocyte subpopulations. Percent CD4 and CD3 were decreased, whereas natural killer cells were increased. Maximum changes occurred around 2 hours, returning to baseline levels at 24 hours. In conclusion, ayahuasca displayed moderate sympathomimetic effects, significant neuroendocrine stimulation, and a time-dependent modulatory effect on cell-mediated immunity. Future studies on the health impact of long-term ayahuasca consumption should consider the assessment of immunological status in regular users. PMID:22005052

  17. Personality, psychopathology, life attitudes and neuropsychological performance among ritual users of Ayahuasca: a longitudinal study.

    Science.gov (United States)

    Bouso, José Carlos; González, Débora; Fondevila, Sabela; Cutchet, Marta; Fernández, Xavier; Ribeiro Barbosa, Paulo César; Alcázar-Córcoles, Miguel Ángel; Araújo, Wladimyr Sena; Barbanoj, Manel J; Fábregas, Josep Maria; Riba, Jordi

    2012-01-01

    Ayahuasca is an Amazonian psychoactive plant beverage containing the serotonergic 5-HT(2A) agonist N,N-dimethyltryptamine (DMT) and monoamine oxidase-inhibiting alkaloids (harmine, harmaline and tetrahydroharmine) that render it orally active. Ayahuasca ingestion is a central feature in several Brazilian syncretic churches that have expanded their activities to urban Brazil, Europe and North America. Members of these groups typically ingest ayahuasca at least twice per month. Prior research has shown that acute ayahuasca increases blood flow in prefrontal and temporal brain regions and that it elicits intense modifications in thought processes, perception and emotion. However, regular ayahuasca use does not seem to induce the pattern of addiction-related problems that characterize drugs of abuse. To study the impact of repeated ayahuasca use on general psychological well-being, mental health and cognition, here we assessed personality, psychopathology, life attitudes and neuropsychological performance in regular ayahuasca users (n = 127) and controls (n = 115) at baseline and 1 year later. Controls were actively participating in non-ayahuasca religions. Users showed higher Reward Dependence and Self-Transcendence and lower Harm Avoidance and Self-Directedness. They scored significantly lower on all psychopathology measures, showed better performance on the Stroop test, the Wisconsin Card Sorting Test and the Letter-Number Sequencing task from the WAIS-III, and better scores on the Frontal Systems Behavior Scale. Analysis of life attitudes showed higher scores on the Spiritual Orientation Inventory, the Purpose in Life Test and the Psychosocial Well-Being test. Despite the lower number of participants available at follow-up, overall differences with controls were maintained one year later. In conclusion, we found no evidence of psychological maladjustment, mental health deterioration or cognitive impairment in the ayahuasca-using group. PMID