Effects of tryptophan depletion on selective serotonin reuptake inhibitor-remitted patients with obsessive compulsive disorder.

Science.gov (United States)

Hood, Sean D; Broyd, Annabel; Robinson, Hayley; Lee, Jessica; Hudaib, Abdul-Rahman; Hince, Dana A

2017-12-01

Serotonergic antidepressants are first-line medication therapies for obsessive-compulsive disorder, however it is not known if synaptic serotonin availability is important for selective serotonin reuptake inhibitor efficacy. The present study tested the hypothesis that temporary reduction in central serotonin transmission, through acute tryptophan depletion, would result in an increase in anxiety in selective serotonin reuptake inhibitor-remitted obsessive-compulsive disorder patients. Eight patients (four males) with obsessive-compulsive disorder who showed sustained clinical improvement with selective serotonin reuptake inhibitor treatment underwent acute tryptophan depletion in a randomized, double-blind, placebo-controlled, within-subjects design, over two days one week apart. Five hours after consumption of the depleting/sham drink the participants performed a personalized obsessive-compulsive disorder symptom exposure task. Psychological responses were measured using the Spielberger State Anxiety Inventory, Yale-Brown Obsessive Compulsive Scale and Visual Analogue Scales. Free plasma tryptophan to large neutral amino acid ratio decreased by 93% on the depletion day and decreased by 1% on the sham day, as anticipated. Psychological rating scores as measured by Visual Analogue Scale showed a significant decrease in perceived control and increase in interfering thoughts at the time of provocation on the depletion day but not on the sham day. A measure of convergent validity, namely Visual Analogue Scale Similar to past, was significantly higher at the time of provocation on both the depletion and sham days. Both the depletion and time of provocation scores for Visual Analogue Scale Anxiety, Spielberger State Anxiety Inventory, Yale-Brown Obsessive Compulsive Scale and blood pressure were not significant. Acute tryptophan depletion caused a significant decrease in perceived control and increase in interfering thoughts at the time of provocation. Acute tryptophan

Mechanism-based PK/PD modeling of selective serotonin reuptake inhibitors

NARCIS (Netherlands)

Geldof, Marian

2007-01-01

The main objective of the investigations was to explore the PK/PD correlations of fluvoxamine, as a prototype for the Selective Serotonin Reuptake Inhibitors (SSRIs). In the various investigations, a spectrum of different biomarkers was used, each reflecting a specific process on the causal path

Use of selective serotonin reuptake inhibitors reduces fertility in men

DEFF Research Database (Denmark)

Nørr, L; Bennedsen, Birgit; Fedder, Jens

2016-01-01

Clinical review of the present data on the effects of selective serotonin reuptake inhibitors (SSRIs) on male fertility was the objective of the study. PubMed and Scopus were searched for publications in English or Danish and reviewed. Human trials, animal studies and in vitro studies were included...

CYP450 genotype and aggressive behavior on selective serotonin reuptake inhibitors

NARCIS (Netherlands)

Ekhart, Corine; Matic, Maja; Kant, Agnes; Schaik, Ron van; van Puijenbroek, Eugène

2017-01-01

AIM: Genetic variants for selective serotonin reuptake inhibitor (SSRI) metabolizing enzymes have been hypothesized to be a risk factor for aggression as adverse drug effect of SSRIs. Our aim was to assess the possible involvement of these polymorphisms on aggression when using SSRIs. MATERIALS &

Antidepressant drugs specifically inhibiting noradrenaline reuptake enhance recognition memory in rats.

Science.gov (United States)

Feltmann, Kristin; Konradsson-Geuken, Åsa; De Bundel, Dimitri; Lindskog, Maria; Schilström, Björn

2015-12-01

Patients suffering from major depression often experience memory deficits even after the remission of mood symptoms, and many antidepressant drugs do not affect, or impair, memory in animals and humans. However, some antidepressant drugs, after a single dose, enhance cognition in humans (Harmer et al., 2009). To compare different classes of antidepressant drugs for their potential as memory enhancers, we used a version of the novel object recognition task in which rats spontaneously forget objects 24 hr after their presentation. Antidepressant drugs were injected systemically 30 min before or directly after the training phase (Session 1 [S1]). Post-S1 injections were used to test for specific memory-consolidation effects. The noradrenaline reuptake inhibitors reboxetine and atomoxetine, as well as the serotonin noradrenaline reuptake inhibitor duloxetine, injected prior to S1 significantly enhanced recognition memory. In contrast, the serotonin reuptake inhibitors citalopram and paroxetine and the cyclic antidepressant drugs desipramine and mianserin did not enhance recognition memory. Post-S1 injection of either reboxetine or citalopram significantly enhanced recognition memory, indicating an effect on memory consolidation. The fact that citalopram had an effect only when injected after S1 suggests that it may counteract its own consolidation-enhancing effect by interfering with memory acquisition. However, pretreatment with citalopram did not attenuate reboxetine's memory-enhancing effect. The D1/5-receptor antagonist SCH23390 blunted reboxetine's memory-enhancing effect, indicating a role of dopaminergic transmission in reboxetine-induced recognition memory enhancement. Our results suggest that antidepressant drugs specifically inhibiting noradrenaline reuptake enhance cognition and may be beneficial in the treatment of cognitive symptoms of depression. (c) 2015 APA, all rights reserved).

Selective Serotonin Reuptake Inhibitor-Induced Sexual Dysfunction in Adolescents: A Review.

Science.gov (United States)

Scharko, Alexander M.

2004-01-01

Objective: To review the existing literature on selective serotonin reuptake inhibitor (SSRI)-induced sexual dysfunction in adolescents. Method: A literature review of SSRI-induced adverse effects in adolescents focusing on sexual dysfunction was done. Nonsexual SSRI-induced adverse effects were compared in adult and pediatric populations.…

Use of selective-serotonin reuptake inhibitors and platelet aggregation inhibitors among individuals with co-occurring atherosclerotic cardiovascular disease and depression or anxiety

Directory of Open Access Journals (Sweden)

J Douglas Thornton

2016-12-01

Full Text Available Objective: Medications commonly used to treat heart disease, anxiety, and depression can interact resulting in an increased risk of bleeding, warranting a cautious approach in medical decision making. This retrospective, descriptive study examined the prevalence and the factors associated with the use of both selective-serotonin reuptake inhibitor and platelet aggregation inhibitor among individuals with co-occurring atherosclerotic cardiovascular disease and anxiety or depression. Methods: Respondents aged 22 years and older, alive throughout the study period, and diagnosed with co-occurring atherosclerotic cardiovascular disease and anxiety or depression (n = 1507 in years 2007 through 2013 of the Medical Expenditures Panel Survey were included. The use of treatment was grouped as follows: selective-serotonin reuptake inhibitor and platelet aggregation inhibitor, selective-serotonin reuptake inhibitor or platelet aggregation inhibitor, and neither selective-serotonin reuptake inhibitor nor platelet aggregation inhibitor. Results: Overall, 16.5% used both selective-serotonin reuptake inhibitor and platelet aggregation inhibitor, 61.2% used selective-serotonin reuptake inhibitor or platelet aggregation inhibitor, and 22.3% used neither selective-serotonin reuptake inhibitor nor platelet aggregation inhibitor. Respondents aged over 65 years (adjusted odds ratio = 1.93 (95% confidence interval = 1.08–3.45 and having a diagnosis of diabetes (adjusted odds ratio = 1.63 (95% confidence interval = 1.15–2.31 and hypertension (adjusted odds ratio = 1.84 (95% confidence interval = 1.04–3.27 were more likely to be prescribed the combination. Conclusion: The drug interaction was prevalent in patients who are already at higher risk of health disparities and worse outcomes thus requiring vigilant evaluation.

Are Selective Serotonin Reuptake Inhibitors Safe for Drivers? What is the Evidence?

NARCIS (Netherlands)

Ravera, Silvia; Ramaekers, Johannes G.; de Jong-van den Berg, Lolkje T. W.; de Gier, Johan J.; de Jong-van den Berg, [No Value

Background: Selective serotonin reuptake inhibitors (SSRIs) are widely used medications to treat several psychiatric diseases and, above all, depression. They seem to be as effective as older antidepressants but have a different adverse effect profile. Despite their favorable safety profile, little

Paediatric outcomes following intrauterine exposure to serotonin reuptake inhibitors: a systematic review

DEFF Research Database (Denmark)

Fenger-Grøn, Jesper; Thomsen, Morten; Andersen, Kristian Skytte

2011-01-01

The use of serotonine reuptake inhibitors (SRIs) is increasing among Danish pregnant women. This systematic review addresses the potential adverse effects on the foetus and child of maternal SRI medication. The literature indicates a slightly increased risk of cardiovascular malformations...

An Open-Label Pilot Study of Combined Augmentation With Creatine Monohydrate and 5-Hydroxytryptophan for Selective Serotonin Reuptake Inhibitor- or Serotonin-Norepinephrine Reuptake Inhibitor-Resistant Depression in Adult Women.

Science.gov (United States)

Kious, Brent M; Sabic, Hana; Sung, Young-Hoon; Kondo, Douglas G; Renshaw, Perry

2017-10-01

Many women with major depressive disorder (MDD) respond inadequately to standard treatments. Augmentation of conventional antidepressants with creatine monohydrate and 5-hydroxytryptophan (5-HTP) could correct deficits in serotonin production and brain bioenergetics associated with depression in women, yielding synergistic benefit. We describe an open-label study of 5-HTP and creatine augmentation in women with MDD who had failed selective serotonin reuptake inhibitor (SSRI) or serotonin-norepinephrine reuptake inhibitor (SNRI) monotherapy. Fifteen women who were adequately adherent to an SSRI or SNRI and currently experiencing MDD, with a 17-item Hamilton Depression Rating Scale (HAM-D) score of 16 or higher, were treated with 5 g of creatine monohydrate daily and 100 mg of 5-HTP twice daily for 8 weeks, with 4 weeks of posttreatment follow-up. The primary outcome was change in mean HAM-D scores. Mean HAM-D scores declined from 18.9 (SD, 2.5) at pretreatment visits to 7.5 (SD, 4.4) (P creatine and 5-HTP may represent an effective augmentation strategy for women with SSRI- or SNRI-resistant depression. Given the limitations of this small, open-label trial, future study in randomized, placebo-controlled trials is warranted.

Can a Selective Serotonin Reuptake Inhibitor Act as a Glutamatergic Modulator?

Directory of Open Access Journals (Sweden)

Marcos Emilio Frizzo, PhD

2017-01-01

Full Text Available Sertraline (Zoloft and fluoxetine (Prozac are selective serotonin reuptake inhibitors whose antidepressant mechanism of action is classically attributed to an elevation of the extracellular levels of serotonin in the synaptic cleft. However, the biological effects of these drugs seem to be more complex than their traditionally described mechanism of action. Among their actions is the inhibition of different types of Na+ and K+ channels, as well as of glutamate uptake activity. The clearance of extracellular glutamate is essential to maintain the central nervous system within physiological conditions, and this excitatory neurotransmitter is removed from the synaptic cleft by astrocyte transporters. This transport depends upon a hyperpolarized membrane potential in astrocytes that is mainly maintained by Kir4.1 K+ channels. The impairment of the Kir4.1 channel activity reduces driving force for the glutamate transporter, resulting in an accumulation of extracellular glutamate. It has been shown that sertraline and fluoxetine inhibit Kir4.1 K+ channels. Recently, we demonstrated that sertraline reduces glutamate uptake in human platelets, which contain a high-affinity Na+-dependent glutamate uptake system, with kinetic and pharmacological properties similar to astrocytes in the central nervous system. Considering these similarities between human platelets and astrocytes, one might ask if sertraline could potentially reduce glutamate clearance in the synaptic cleft and consequently modulate glutamatergic transmission. This possibility merits investigation, since it may provide additional information regarding the mechanism of action and perhaps the side effects of these antidepressants.

A concise total synthesis of (R)-fluoxetine, a potent and selective serotonin reuptake inhibitor

International Nuclear Information System (INIS)

Fatima, Angelo de; Lapis, Alexandre Augusto M.; Pilli, Ronaldo A.

2005-01-01

(R)-Fluoxetine, potent and selective serotonin reuptake inhibitor, has been synthesized in six steps, 50% overall yield and 99% ee from benzaldehyde via catalytic asymmetric allylation with Maruoka's catalyst. (author)

A concise total synthesis of (R)-fluoxetine, a potent and selective serotonin reuptake inhibitor

Energy Technology Data Exchange (ETDEWEB)

Fatima, Angelo de; Lapis, Alexandre Augusto M.; Pilli, Ronaldo A. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica]. E-mail: pilli@iqm.unicamp.br

2005-05-15

(R)-Fluoxetine, potent and selective serotonin reuptake inhibitor, has been synthesized in six steps, 50% overall yield and 99% ee from benzaldehyde via catalytic asymmetric allylation with Maruoka's catalyst. (author)

The effect of selective serotonin reuptake inhibitors in healthy subjects. A systematic review

DEFF Research Database (Denmark)

Knorr, Ulla; Kessing, Lars Vedel; Knorr, Ulla

2010-01-01

BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) show antidepressant properties in many patients with a diagnosis of depression. An understanding of the underlying mechanisms of the effect of SSRIs in healthy patients may lead to an understanding of the yet unclear pathophysiology of d...

Increased Bleeding Risk With Concurrent Use of Selective Serotonin Reuptake inhibitors and Coumarins

NARCIS (Netherlands)

Schalekamp, Tom; Klungel, Olaf H; Souverein, Patrick C; de Boer, Anthonius

2008-01-01

BACKGROUND: Treatment with vitamin K antagonists (coumarins) is associated with an increased risk of bleeding. Because use of selective serotonin reuptake inhibitors (SSRIs) is also associated with an increased risk of bleeding, we assessed the odds ratio (OR) of abnormal bleeding associated with

Comparative efficacy and safety of selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors in older adults: a network meta-analysis.

Science.gov (United States)

Thorlund, Kristian; Druyts, Eric; Wu, Ping; Balijepalli, Chakrapani; Keohane, Denis; Mills, Edward

2015-05-01

To establish the comparative efficacy and safety of selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors in older adults using the network meta-analysis approach. Systematic review and network meta-analysis. Individuals aged 60 and older. Data on partial response (defined as at least 50% reduction in depression score from baseline) and safety (dizziness, vertigo, syncope, falls, loss of consciousness) were extracted. A Bayesian network meta-analysis was performed on the efficacy and safety outcomes, and relative risks (RRs) with 95% credible intervals (CrIs) were produced. Fifteen randomized controlled trials were eligible for inclusion in the analysis. Citalopram, escitalopram, paroxetine, duloxetine, venlafaxine, fluoxetine, and sertraline were represented. Reporting on partial response and dizziness was sufficient to conduct a network meta-analysis. Reporting on other outcomes was sparse. For partial response, sertraline (RR=1.28), paroxetine (RR=1.48), and duloxetine (RR=1.62) were significantly better than placebo. The remaining interventions yielded RRs lower than 1.20. For dizziness, duloxetine (RR=3.18) and venlafaxine (RR=2.94) were statistically significantly worse than placebo. Compared with placebo, sertraline had the lowest RR for dizziness (1.14) and fluoxetine the second lowest (1.31). Citalopram, escitalopram, and paroxetine all had RRs between 1.4 and 1.7. There was clear evidence of the effectiveness of sertraline, paroxetine, and duloxetine. There also appears to be a hierarchy of safety associated with the different antidepressants, although there appears to be a dearth of reporting of safety outcomes. © 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society.

Commentary: Considerations on the Pharmacological Treatment of Compulsions and Stereotypies with Serotonin Reuptake Inhibitors in Pervasive Developmental Disorders.

Science.gov (United States)

Gordon, C. T.

2000-01-01

This commentary discusses study results that indicate the nonselective serotonin reuptake inhibitor (SRI) clomipramine is more efficacious than the relatively selective norepinephrine reuptake inhibitor desipramine and placebo in treating repetitive or ritualized behaviors in children with autism. The need for concurrent genetic and biochemical…

In utero exposure to selective serotonin reuptake inhibitors and risk for autism spectrum disorder

DEFF Research Database (Denmark)

Gidaya, Nicole B; Lee, Brian K; Burstyn, Igor

2014-01-01

We investigated whether there is an association between increased risk for autism spectrum disorders (ASD) and selective serotonin reuptake inhibitors (SSRIs) used during pregnancy. This study used Denmark's health and population registers to obtain information regarding prescription drugs, ASD...

The treatment of kleptomania with serotonin reuptake inhibitors.

Science.gov (United States)

Lepkifker, E; Dannon, P N; Ziv, R; Iancu, I; Horesh, N; Kotler, M

1999-01-01

Kleptomania is characterized by an irresistible impulse to steal objects not needed for personal use or for their monetary value. Several recent case reports have shown that Serotonin Specific Reuptake Inhibitors (SSRIs) could be effective in the treatment of kleptomania just as it is in other obsessive-compulsive spectrum disorders. We report five cases of kleptomania patients who were successfully treated with fluoxetine or paroxetine in combination with a psychotherapeutic intervention. In one case, the discontinuation of the medication repeatedly led to the resurgence of the kleptomanic behavior. Our case series illustrates the effectiveness of SSRIs in kleptomania. It thus supports the assumption that this syndrome involves a dysfunctional serotoninergic mechanism.

Synthesis and evaluation of racemic [11C]NS2456 and its enantiomers as selective serotonin reuptake radiotracers for PET

International Nuclear Information System (INIS)

Smith, D.F.; Bender, D.; Marthi, K.; Cumming, P.; Hansen, S.B.; Peters, D.; Oestergaard Nielsen, E.; Scheel-Krueger, J.; Gjedde, A.

2001-01-01

Positron emission tomography (PET) radiotracers are needed for quantifying serotonin uptake sites in the living brain. Therefore, we evaluated a new selective serotonin reuptake inhibitor, NS2456, to determine whether it is suited for use in PET. Racemic NS2456 [(1RS,5SR)-8-methyl-3-[4-trifluoromethoxyphenyl]-8-azabicyclo [3.2.1]oct-2-ene] and its N-demethylated analog, racemic NS2463, selectively inhibited serotonin uptake in rat brain synaptosomes; their IC 50 values were 3000-fold lower for [ 3 H]serotonin than for either [ 3 H]dopamine or [ 3 H]noradrenaline. The enantiomers of NS2463 were also potent inhibitors of serotonin uptake in vitro, but they failed to show stereoselectivity. Racemic NS2463 as well as its enantiomers were radiolabelled by N-methylation with C-11, yielding [ 11 C]NS2456 for use in PET of the living porcine brain. The compounds crossed the blood-brain barrier rapidly and accumulated preferentially in regions rich in serotonin uptake sites (e.g., brainstem, subthalamus and thalamus). However, their binding potentials were relatively low and no stereoselectivity was found. Thus, neither racemic [ 11 C]NS2456 nor its [ 11 C]-labelled enantiomers are ideal for PET neuroimaging of neuronal serotonin uptake sites

Anhedonia Predicts Poorer Recovery among Youth with Selective Serotonin Reuptake Inhibitor Treatment-Resistant Depression

Science.gov (United States)

McMakin, Dana L.; Olino, Thomas M.; Porta, Giovanna; Dietz, Laura J.; Emslie, Graham; Clarke, Gregory; Wagner, Karen Dineen; Asarnow, Joan R.; Ryan, Neal D.; Birmaher, Boris; Shamseddeen, Wael; Mayes, Taryn; Kennard, Betsy; Spirito, Anthony; Keller, Martin; Lynch, Frances L.; Dickerson, John F.; Brent, David A.

2012-01-01

Objective: To identify symptom dimensions of depression that predict recovery among selective serotonin reuptake inhibitor (SSRI) treatment-resistant adolescents undergoing second-step treatment. Method: The Treatment of Resistant Depression in Adolescents (TORDIA) trial included 334 SSRI treatment-resistant youth randomized to a medication…

An Association Between Selective Serotonin Reuptake Inhibitor Use and Serious Upper Gastrointestinal Bleeding

DEFF Research Database (Denmark)

Dall, Michael; Schaffalitzky de Muckadell, Ove B; Lassen, Annmarie Touborg

2009-01-01

BACKGROUND & AIMS: In vitro studies have shown that selective serotonin reuptake inhibitors (SSRIs) inhibit platelet aggregation. It is controversial whether use of SSRIs is a cause of clinically important bleeding; results from observational studies have been equivocal. METHODS: A population......-based case-control study was conducted in the county of Funen, Denmark. The 3652 cases all had a first discharge diagnosis of serious upper gastrointestinal bleeding (UGB) from 1995 to 2006. All cases were manually validated. Controls (n = 36,502), matched for age and sex, were selected by risk-set sampling....... Data on drug exposure and medical history were retrieved from a prescription database and the county's patient register. Confounders were controlled for by conditional logistic regression and the case-crossover design. RESULTS: The adjusted odds ratio (OR) of UGB among current, recent, and past users...

A non-selective (amitriptyline), but not a selective (citalopram), serotonin reuptake inhibitor is effective in the prophylactic treatment of chronic tension-type headache.

OpenAIRE

Bendtsen, L; Jensen, R; Olesen, J

1996-01-01

OBJECTIVES: Although the tricyclic antidepressant amitriptyline is extensively used in the prophylactic treatment of chronic tension-type headache, only few studies have investigated the efficacy of this treatment and the results are contradictory. In addition, the new selective serotonin reuptake inhibiting antidepressants, which are widely used in depression and of potential value in pain management, have never been investigated in a placebo controlled study of tension-type headache. The ai...

In Utero Exposure to Selective Serotonin Reuptake Inhibitors and Risk for Autism Spectrum Disorder

Science.gov (United States)

Gidaya, Nicole B.; Lee, Brian K.; Burstyn, Igor; Yudell, Michael; Mortensen, Erik L.; Newschaffer, Craig J.

2014-01-01

We investigated whether there is an association between increased risk for autism spectrum disorders (ASD) and selective serotonin reuptake inhibitors (SSRIs) used during pregnancy. This study used Denmark's health and population registers to obtain information regarding prescription drugs, ASD diagnosis, and health and socioeconomic status. There…

A controlled study of a serotonin reuptake blocker, zimelidine, in the treatment of chronic pain.

Science.gov (United States)

Gourlay, G K; Cherry, D A; Cousins, M J; Love, B L; Graham, J R; McLachlan, M O

1986-04-01

Zimelidine inhibits the central neuronal reuptake of serotonin and has undergone clinical evaluation as an antidepressant. Twenty patients with chronic pain of non-malignant origin (mean duration 15.8 years) were entered into a double blind cross-over study of the analgesic efficacy of zimelidine and placebo. The duration of each treatment phase was 6 weeks and there was a comprehensive assessment of each patient prior to the commencement and at the completion of the study, during a brief period of hospitalisation. Zimelidine was superior (P less than 0.05) to placebo with respect to pain relief based on a global assessment (by the clinical investigators) performed at the completion of each treatment phase. However, there was no significant difference in analgesic efficacy between the zimelidine and placebo treatment phases based on the following criteria: (a) changes in the minimum effective blood concentration of pethidine necessary to provide pain relief in each patient, measured during a pethidine infusion of 1.67 mg/min for 60 min; (b) changes in pain scores estimated by patients using the visual analogue pain scale (VAPS); (c) changes in patients' estimates of pain intensity associated with various daily activities. Significant pain relief was apparent within 2-3 days in those patients who had a beneficial effect, which contrasts with the documented 3-4 weeks for maximal antidepressant effects. The results of this study suggest that serotonin reuptake blockers do not provide consistent pain relief in patients with chronic pain, but may contribute an analgesic effect in the treatment of some patients.

The age-dependent effects of selective serotonin reuptake inhibitors in humans and rodents: A review.

NARCIS (Netherlands)

Olivier, J.D.A.; Blom, T.; Arentsen, T.; Homberg, J.R.

2011-01-01

The selective serotonin reuptake inhibitor (SSRI) Prozac(R) (fluoxetine) is widely prescribed for the treatment of depression and anxiety-related disorders. While extensive research has established that fluoxetine is safe for adults, safety is not guaranteed for (unborn) children and adolescents.

Are Selective Serotonin Reuptake Inhibitors Safe for Drivers? What is the Evidence?

OpenAIRE

Ravera, Silvia; Ramaekers, Johannes G.; de Jong-van den Berg, Lolkje T. W.; de Gier, Johan J.; de Jong-van den Berg, [No Value

2012-01-01

Background: Selective serotonin reuptake inhibitors (SSRIs) are widely used medications to treat several psychiatric diseases and, above all, depression. They seem to be as effective as older antidepressants but have a different adverse effect profile. Despite their favorable safety profile, little is known about their influence on traffic safety. Objective: To conduct a literature review to summarize the current evidence on the role of SSRIs in traffic safety, particularly concerning undesir...

Helicobacter pylori and risk of upper gastrointestinal bleeding among users of selective serotonin reuptake inhibitors

DEFF Research Database (Denmark)

Dall, Michael; Schaffalitzky de Muckadell, Ove B; Møller Hansen, Jane

2011-01-01

A number of studies have reported a possible association between use of selective serotonin reuptake inhibitors (SSRIs) and serious upper gastrointestinal bleeding (UGB). We conducted this case-control study to assess if Helicobacter pylori (H. pylori) potentiates the risk of serious UGB in SSRI ...

Discovery of a potent, dual serotonin and norepinephrine reuptake inhibitor.

Science.gov (United States)

Dreyfus, Nicolas; Myers, Jason K; Badescu, Valentina O; de Frutos, Oscar; de la Puente, Maria Luz; Ding, Chunjin; Filla, Sandra A; Fynboe, Karsten; Gernert, Douglas L; Heinz, Beverly A; Hemrick-Luecke, Susan K; Johnson, Kirk W; Johnson, Michael P; López, Pilar; Love, Patrick L; Martin, Laura J; Masquelin, Thierry; McCoy, Michael J; Mendiola, Javier; Morrow, Denise; Muhlhauser, Mark; Pascual, Gustavo; Perun, Thomas J; Pfeifer, Lance A; Phebus, Lee A; Richards, Simon J; Rincón, Juan Antonio; Seest, Eric P; Shah, Jikesh; Shaojuan, Jia; Simmons, Rosa Maria A; Stephenson, Gregory A; Tromiczak, Eric G; Thompson, Linda K; Walter, Magnus W; Weber, Wayne W; Zarrinmayeh, Hamideh; Thomas, Craig E; Joshi, Elizabeth; Iyengar, Smriti; Johansson, Anette M

2013-06-13

The objective of the described research effort was to identify a novel serotonin and norepinephrine reuptake inhibitor (SNRI) with improved norepinephrine transporter activity and acceptable metabolic stability and exhibiting minimal drug-drug interaction. We describe herein the discovery of a series of 3-substituted pyrrolidines, exemplified by compound 1. Compound 1 is a selective SNRI in vitro and in vivo, has favorable ADME properties, and retains inhibitory activity in the formalin model of pain behavior. Compound 1 thus represents a potential new probe to explore utility of SNRIs in central nervous system disorders, including chronic pain conditions.

Ecstasy use and serotonin syndrome: a neglected danger to adolescents and young adults prescribed selective serotonin reuptake inhibitors.

Science.gov (United States)

Dobry, Yuriy; Rice, Timothy; Sher, Leo

2013-01-01

At present, there are scarce clinical and basic lab data concerning the risk of acute serotonin toxicity from selective serotonin reuptake inhibitors (SSRIs) and 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) co-administration. The health care community can strongly benefit from efforts to address the high risks associated with serotonin syndrome from this specific drug combination. The aim of this work is to review the risk of serotonin syndrome in adolescents and young adults prescribed with SSRIs and are concurrently using ecstasy. An electronic search of the major behavioral science bibliographic databases (Pubmed, PsycINFO, Medline) was conducted to retrieve peer-reviewed articles, which detail the clinical characteristics, biological mechanisms and social implications of SSRIs, MDMA, and their potential synergism in causing serotonin syndrome in the pediatric and young adult population. Search terms included "serotonin syndrome", "ecstasy", "MDMA", "pediatric", and "SSRI". Additional references were incorporated from the bibliographies of these retrieved articles. MDMA, in combination with the widely-prescribed SSRI antidepressant class, can lead to rapid, synergistic rise of serotonin (5-HT) concentration in the central nervous system, leading to the acute medical emergency known as serotonin syndrome. This review addresses such complication through an exploration of the theoretical mechanisms and clinical manifestations of this life-threatening pharmacological interaction. The increasing incidences of recreational ecstasy use and SSRI pharmacotherapy among multiple psychiatric disorders in the adolescent population have made this an overlooked yet increasingly relevant danger, which poses a threat to public health. This can be curbed through further research, as well as greater health care provision and attention from a regulatory body owing.

Selective serotonin reuptake inhibitor antidepressant use in first trimester pregnancy and risk of specific congenital anomalies

DEFF Research Database (Denmark)

Wemakor, Anthony; Casson, Karen; Garne, Ester

2015-01-01

Evidence of an association between early pregnancy exposure to selective serotonin reuptake inhibitors (SSRI) and congenital heart defects (CHD) has contributed to recommendations to weigh benefits and risks carefully. The objective of this study was to determine the specificity of association be...

Switching antidepressants after a first selective serotonin reuptake inhibitor in major depressive disorder: a systematic review

NARCIS (Netherlands)

Ruhé, Henricus G.; Huyser, Jochanan; Swinkels, Jan A.; Schene, Aart H.

2006-01-01

OBJECTIVE: Selective serotonin reuptake inhibitors (SSRIs) are frequently used as a first antidepressant for major depressive disorder but have response rates of 50% to 60% in daily practice. For patients with insufficient response to SSRIs, switching is often applied. This article aims to

Use of selective serotonin reuptake inhibitors and risk of re-operation due to post-surgical bleeding in breast cancer patients: a Danish population-based cohort study

DEFF Research Database (Denmark)

Gärtner, Rune; Cronin-Fenton, Deirdre; Hundborg, Heidi Holmager

2010-01-01

Selective serotonin reuptake inhibitors (SSRI) decrease platelet-function, which suggests that SSRI use may increase the risk of post-surgical bleeding. Few studies have investigated this potential association.......Selective serotonin reuptake inhibitors (SSRI) decrease platelet-function, which suggests that SSRI use may increase the risk of post-surgical bleeding. Few studies have investigated this potential association....

Upper gastrointestinal bleeding in a patient with depression receiving selective serotonin reuptake inhibitor therapy.

Science.gov (United States)

Kumar, Deepak; Saaraswat, Tanuj; Sengupta, S N; Mehrotra, Saurabh

2009-02-01

Serotonin plays an important role in the normal clotting phenomenon and is released by platelets. Platelets are dependent on a serotonin transporter for the uptake of serotonin, as they cannot synthesize it themselves. Selective serotonin reuptake inhibitors (SSRIs) block the uptake of serotonin into platelets and can cause problems with clotting leading to bleeding. This case report highlights the occurrence of upper gastrointestinal bleeding in the index case on initiating SSRI therapy for depression and the prompt resolution of the same on its discontinuation on two separate occasions. SSRIs may cause upper gastrointestinal (GI) bleeding. Physicians should be aware of the same and should try to rule out previous episodes of upper GI bleed or the presence of other risk factors which might predispose to it before prescribing SSRIs; they should also warn the patients about this potential side effect. Also, the presence of thalassemia trait in the index patient deserves special attention and needs to be explored to see if it might in any way contribute in potentiating this side effect of SSRIs.

Maternal use of selective serotonin reuptake inhibitors during pregnancy is associated with Hirschsprung's disease in newborns - a nationwide cohort study

DEFF Research Database (Denmark)

Nielsen, Sebastian Werngreen; Møller Ljungdalh, Pernille; Nielsen, Jan

2017-01-01

of the association between maternal use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy and development of Hirschsprung's Disease in the newborn child. The study examined a nationwide, unselected cohort of children born in Denmark from 1 January 1996 until 12 March 2016 (n = 1,256,317). We...... of Hirschsprung's disease was 16/19.807 (0.08%) compared to 584/1.236.510 (0.05%) in the unexposed cohort. In women who redeemed a minimum of one prescription of selective serotonin reuptake inhibitors, the adjusted odds ratio for development of Hirschsprung's disease was 1.76 (95%CI: 1.07-2.92). In women who...

Treatment of Selective Serotonin Reuptake Inhibitor-Resistant Depression in Adolescents: Predictors and Moderators of Treatment Response

Science.gov (United States)

Asarnow, Joan Rosenbaum; Emslie, Graham; Clarke, Greg; Wagner, Karen Dineen; Spirito, Anthony; Vitiello, Benedetto; Iyengar, Satish; Shamseddeen, Wael; Ritz, Louise; Birmaher, Boris; Ryan, Neal; Kennard, Betsy; Mayes, Taryn; DeBar, Lynn; McCracken, James; Strober, Michael; Suddath, Robert; Leonard, Henrietta; Porta, Giovanna; Keller, Martin; Brent, David

2009-01-01

Adolescents who did not improve with Selective Serotonin Reuptake Inhibitor (SSRI) were provided an alternative SSRI plus cognitive-behavioral therapy (CBT). The superiority of the CBT/combined treatment as compared to medication alone is more evident in youths who had more comorbid disorders, no abuse history, and lower hopelessness.

Combinatorial support vector machines approach for virtual screening of selective multi-target serotonin reuptake inhibitors from large compound libraries.

Science.gov (United States)

Shi, Z; Ma, X H; Qin, C; Jia, J; Jiang, Y Y; Tan, C Y; Chen, Y Z

2012-02-01

Selective multi-target serotonin reuptake inhibitors enhance antidepressant efficacy. Their discovery can be facilitated by multiple methods, including in silico ones. In this study, we developed and tested an in silico method, combinatorial support vector machines (COMBI-SVMs), for virtual screening (VS) multi-target serotonin reuptake inhibitors of seven target pairs (serotonin transporter paired with noradrenaline transporter, H(3) receptor, 5-HT(1A) receptor, 5-HT(1B) receptor, 5-HT(2C) receptor, melanocortin 4 receptor and neurokinin 1 receptor respectively) from large compound libraries. COMBI-SVMs trained with 917-1951 individual target inhibitors correctly identified 22-83.3% (majority >31.1%) of the 6-216 dual inhibitors collected from literature as independent testing sets. COMBI-SVMs showed moderate to good target selectivity in misclassifying as dual inhibitors 2.2-29.8% (majority virtual hits correlate with the reported effects of their predicted targets. COMBI-SVM is potentially useful for searching selective multi-target agents without explicit knowledge of these agents. Copyright © 2011 Elsevier Inc. All rights reserved.

Maternal use of selective serotonin reuptake inhibitors and risk of miscarriage

DEFF Research Database (Denmark)

Johansen, Rie Laurine Rosenthal; Mortensen, Laust Hvas; Andersen, Anne-Marie Nybo

2015-01-01

-exposed pregnancies were characterised by an unhealthier maternal lifestyle and mental health profile than unexposed pregnancies, whereas no convincing differences were observed between pregnancies exposed to SSRIs during versus before pregnancy. Substantial disagreement was found between prescriptions and self......BACKGROUND: The use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy has been associated with miscarriage, but the association may be biased by maternal mental illness, lifestyle and exposure misclassification. METHODS: A register study on all pregnancies in Denmark between 1996......-reported use of SSRIs, but it did not affect the estimated hazard ratios. CONCLUSION: Confounding by indication and lifestyle in pregnancy may explain the association between SSRI use and miscarriage....

Selective serotonin reuptake inhibitorprescribing before, during and after pregnancy

DEFF Research Database (Denmark)

Charlton, Ra; Jordan, S; Pierini, A

2015-01-01

OBJECTIVE: To explore the prescribing patterns of selective serotonin reuptake inhibitors (SSRIs) before, during and after pregnancy in six European population-based databases. DESIGN: Descriptive drug utilisation study. SETTING: Six electronic healthcare databases in Denmark, the Netherlands......, Italy (Emilia Romagna/Tuscany), Wales and the rest of the UK. POPULATION: All women with a pregnancy ending in a live or stillbirth starting and ending between 2004 and 2010. METHODS: A common protocol was implemented across databases to identify SSRI prescriptions issued (UK) or dispensed (non......-UK) in the year before, during or in the year following pregnancy. MAIN OUTCOME MEASURES: The percentage of deliveries in which the woman received an SSRI prescription in the year before, during or in the year following pregnancy. We also compared the choice of SSRIs and changes in prescribing over the study...

The effect of antenatal depression and selective serotonin reuptake inhibitor treatment on nerve growth factor signaling in human placenta

NARCIS (Netherlands)

Kaihola, Helena; Olivier, Jocelien; Poromaa, Inger Sundström; Åkerud, Helena

2015-01-01

Depressive symptoms during pregnancy are common and may have impact on the developing child. Selective serotonin reuptake inhibitors (SSRIs) are the most prescribed antidepressant treatment, but unfortunately, these treatments can also negatively affect the behavioral development and health of a

Triple Reuptake Inhibitors: The Next Generation of Antidepressants

OpenAIRE

Marks, David M; Pae, Chi-Un; Patkar, Ashwin A

2008-01-01

Depression has been associated with impaired neurotransmission of serotonergic, norepinephrinergic, and dopaminergic pathways, although most pharmacologic treatment strategies for depression enhance only serotonin and norepinephrine neurotransmission. Current drug development efforts are aimed at a new class of antidepressants which inhibit the reuptake of all three neurotransmitters in the hope of creating medications with broader efficacy and/or quicker onset of action. The current review e...

Differences in the dynamics of serotonin reuptake transporter occupancy may explain superior clinical efficacy of escitalopram versus citalopram.

Science.gov (United States)

Kasper, Siegfried; Sacher, Julia; Klein, Nikolas; Mossaheb, Nilufar; Attarbaschi-Steiner, Trawat; Lanzenberger, Rupert; Spindelegger, Christoph; Asenbaum, Susanne; Holik, Alexander; Dudczak, Robert

2009-05-01

Escitalopram the S-enantiomer of the racemate citalopram, is clinically more effective than citalopram in the treatment of major depressive disorder. However, the precise mechanism by which escitalopram achieves superiority over citalopram is yet to be determined. It has been hypothesized that the therapeutically inactive R-enantiomer competes with the serotonin-enhancing S-enantiomer at a low-affinity allosteric site on serotonin reuptake transporters (SERTs), and reduces the effectiveness of the S-enantiomer at the primary, high-affinity serotonin-binding site. This study summarizes the results of two recent single-photon emission computerized tomography studies measuring SERT occupancy in citalopram-treated and escitalopram-treated healthy volunteers, after a single dose and multiple doses (i.e. under steady-state conditions). The single-dose study showed no attenuating effect of R-citalopram. After multiple dosing, however, SERT occupancy was significantly reduced in the presence of R-citalopram. Under steady-state conditions, R-enantiomer concentrations were greater than for the S-enantiomer because of slower clearance of R-citalopram. A pooled analysis suggests that build-up of the R-enantiomer after repeated citalopram dosing may lead to increased inhibition of S-enantiomer occupancy of SERT. This review adds to the growing body of evidence regarding differences in the dynamics of SERT occupancy, that is, molecular mechanisms underlying the often-observed superior clinical efficacy of escitalopram compared with citalopram in major depressive disorder.

Amphetamine Action at the Cocaine- and Antidepressant-Sensitive Serotonin Transporter Is Modulated by αCaMKII

DEFF Research Database (Denmark)

Steinkellner, Thomas; Montgomery, Therese R; Hofmaier, Tina

2015-01-01

Serotonergic neurotransmission is terminated by reuptake of extracellular serotonin (5-HT) by the high-affinity serotonin transporter (SERT). Selective 5-HT reuptake inhibitors (SSRIs) such as fluoxetine or escitalopram inhibit SERT and are currently the principal treatment for depression and anx...... and efflux at monoamine transporters are asymmetric processes that can be targeted separately. Ultimately, this may provide a molecular mechanism for putative drug developments to treat amphetamine addiction....

Triple Reuptake Inhibitors: A Premise and Promise

OpenAIRE

Marks, David M.; Pae, Chi-Un; Patkar, Ashwin A.

2008-01-01

On the horizon there is a new class of psychoactive medications which work by inhibiting the neuronal reuptake of serotonin, norepinephrine, and dopamine. There are multiple potential indications for these drugs. Research suggests that they may have a role in treating depressive disorders, and it is plausible they may have potential efficacy in obesity, addiction, and pain syndromes. The current review describes some of the molecules in development presently and explores the research relevant...

Effects of acute administration of selective serotonin reuptake inhibitors on sympathetic nerve activity

International Nuclear Information System (INIS)

Tiradentes, R.V.; Pires, J.G.P.; Silva, N.F.; Ramage, A.G.; Santuzzi, C.H.; Futuro, H.A. Neto

2014-01-01

Serotonergic mechanisms have an important function in the central control of circulation. Here, the acute effects of three selective serotonin (5-HT) reuptake inhibitors (SSRIs) on autonomic and cardiorespiratory variables were measured in rats. Although SSRIs require 2-3 weeks to achieve their full antidepressant effects, it has been shown that they cause an immediate inhibition of 5-HT reuptake. Seventy male Wistar rats were anesthetized with urethane and instrumented to record blood pressure, heart rate, renal sympathetic nerve activity (RSNA), and respiratory frequency. At lower doses, the acute cardiovascular effects of fluoxetine, paroxetine and sertraline administered intravenously were insignificant and variable. At middle and higher doses, a general pattern was observed, with significant reductions in sympathetic nerve activity. At 10 min, fluoxetine (3 and 10 mg/kg) reduced RSNA by -33±4.7 and -31±5.4%, respectively, without changes in blood pressure; 3 and 10 mg/kg paroxetine reduced RSNA by -35±5.4 and -31±5.5%, respectively, with an increase in blood pressure +26.3±2.5; 3 mg/kg sertraline reduced RSNA by -59.4±8.6%, without changes in blood pressure. Sympathoinhibition began 5 min after injection and lasted approximately 30 min. For fluoxetine and sertraline, but not paroxetine, there was a reduction in heart rate that was nearly parallel to the sympathoinhibition. The effect of these drugs on the other variables was insignificant. In conclusion, acute peripheral administration of SSRIs caused early autonomic cardiovascular effects, particularly sympathoinhibition, as measured by RSNA. Although a peripheral action cannot be ruled out, such effects are presumably mostly central

Effects of acute administration of selective serotonin reuptake inhibitors on sympathetic nerve activity

Energy Technology Data Exchange (ETDEWEB)

Tiradentes, R.V. [Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Centro Universitário do Espírito Santo, Colatina, ES (Brazil); Pires, J.G.P. [Centro Universitário do Espírito Santo, Colatina, ES (Brazil); Escola de Medicina da Empresa Brasileira de Ensino, Vitória, ES (Brazil); Silva, N.F. [Departamento de Morfologia, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Ramage, A.G. [Department of Neuroscience, Physiology and Pharmacology, University College London, London (United Kingdom); Santuzzi, C.H. [Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Centro Universitário do Espírito Santo, Colatina, ES (Brazil); Futuro, H.A. Neto [Escola de Medicina da Empresa Brasileira de Ensino, Vitória, ES (Brazil); Departamento de Morfologia, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Escola Superior de Ciências da Saúde, Santa Casa de Misericórdia de Vitória, Vitória, ES (Brazil)

2014-05-30

Serotonergic mechanisms have an important function in the central control of circulation. Here, the acute effects of three selective serotonin (5-HT) reuptake inhibitors (SSRIs) on autonomic and cardiorespiratory variables were measured in rats. Although SSRIs require 2-3 weeks to achieve their full antidepressant effects, it has been shown that they cause an immediate inhibition of 5-HT reuptake. Seventy male Wistar rats were anesthetized with urethane and instrumented to record blood pressure, heart rate, renal sympathetic nerve activity (RSNA), and respiratory frequency. At lower doses, the acute cardiovascular effects of fluoxetine, paroxetine and sertraline administered intravenously were insignificant and variable. At middle and higher doses, a general pattern was observed, with significant reductions in sympathetic nerve activity. At 10 min, fluoxetine (3 and 10 mg/kg) reduced RSNA by -33±4.7 and -31±5.4%, respectively, without changes in blood pressure; 3 and 10 mg/kg paroxetine reduced RSNA by -35±5.4 and -31±5.5%, respectively, with an increase in blood pressure +26.3±2.5; 3 mg/kg sertraline reduced RSNA by -59.4±8.6%, without changes in blood pressure. Sympathoinhibition began 5 min after injection and lasted approximately 30 min. For fluoxetine and sertraline, but not paroxetine, there was a reduction in heart rate that was nearly parallel to the sympathoinhibition. The effect of these drugs on the other variables was insignificant. In conclusion, acute peripheral administration of SSRIs caused early autonomic cardiovascular effects, particularly sympathoinhibition, as measured by RSNA. Although a peripheral action cannot be ruled out, such effects are presumably mostly central.

Inhibition of serotonin release by bombesin-like peptides in rat hypothalamus in vitro

International Nuclear Information System (INIS)

Saporito, M.S.; Warwick, R.O. Jr.

1989-01-01

We investigated the activity of bombesin (BN), neuromedin-C (NM-C) and neuromedin-B (NM-B) on serotonin (5-HT) release and reuptake in rat hypothalamus (HYP) in vitro. BN and NM-C but not NM-B decreased K + evoked 3 H-5-HT release from superfused HYP slices by 25%. Bacitracin, a nonspecific peptidase inhibitor, reversed the inhibitory effect of BN on K + evoked 3 H-5-HT release. Phosphoramidon (PAN, 10 μM) an endopeptidase 24.11 inhibitor, abolished the inhibitory effect of BN, but not NM-C, on K + evoked 3 H-5-HT release. The peptidyl dipeptidase A inhibitor enalaprilat (ENP, 10 μM), enhanced both BN and NM-C inhibition of 3 H-5-HT release. Bestatin (BST, 10 μM) had no effect on BN or NM-C inhibitory activity on 3 H-5-HT release. Neither BN, NM-C nor NM-B affected reuptake of 3 H-5-HT into HYP synaptosomes alone or in combination with any of the peptidase inhibitors, nor did these peptides alter the ability of fluoxetine to inhibit 3 H-5-HT uptake

A Concise Total Synthesis of (R)-Fluoxetine, a Potent and Selective Serotonin Reuptake Inhibitor

OpenAIRE

de Fátima, Ângelo; Lapis, Alexandre Augusto M.; Pilli, Ronaldo A.

2005-01-01

(R)-Fluoxetine, potent and selective serotonin reuptake inhibitor, has been synthesized in six steps, 50% overall yield and 99% ee from benzaldehyde via catalytic asymmetric allylation with Maruoka's catalyst. (R)-Fluoxetina, um inibidor potente e seletivo da recaptação da serotonina, foi sintetizada em seis etapas, 50% de rendimento total e 99% de excesso enantiomérico a partir do benzaldeído via alilação catalítica assimétrica empregando-se o sistema catalítico desenvolvido por Maruoka e...

Early Neurological Outcome of Young Infants Exposed to Selective Serotonin Reuptake Inhibitors during Pregnancy : Results from the Observational SMOK Study

NARCIS (Netherlands)

de Vries, N.K.S.; van der Veere, C.N.; Reijneveld, S.A.; Bos, A.F.

2013-01-01

Background: Use of selective serotonin reuptake inhibitors (SSRI) during pregnancy is common while the effect on the infant's neurological outcome is unknown. Our objective was to determine the effects of prenatal SSRI-exposure on the infants' neurological functioning, adjusted for maternal mental

Selective serotonin reuptake inhibitor suppression of HIV infectivity and replication.

Science.gov (United States)

Benton, Tami; Lynch, Kevin; Dubé, Benoit; Gettes, David R; Tustin, Nancy B; Ping Lai, Jian; Metzger, David S; Blume, Joshua; Douglas, Steven D; Evans, Dwight L

2010-11-01

To test the hypothesis that the selective serotonin reuptake inhibitor (SSRI) citalopram would down-regulate human immunodeficiency virus (HIV) infectivity and that the greatest effects would be seen in people with depression. Depression is a risk factor for morbidity and mortality in HIV/acquired immune deficiency syndrome. Serotonin (5-HT) neurotransmission has been implicated in the pathobiology of depression, and pharmacologic therapies for depression target this system. The 5-HT transporter and 5-HT receptors are widely distributed throughout the central nervous and immune systems. Depression has been associated with suppression of natural killer cells and CD8(+) lymphocytes, key regulators of HIV infection. Ex vivo models for acute and chronic HIV infection were used to study the effects of citalopram on HIV viral infection and replication in 48 depressed and nondepressed women. For both the acute and chronic infection models, HIV reverse transcriptase activity was measured in the citalopram treatment condition and the control condition. The SSRI significantly down-regulated the reverse transcriptase response in both the acute and chronic infection models. Specifically, citalopram significantly decreased the acute HIV infectivity of macrophages. Citalopram also significantly decreased HIV viral replication in the latently infected T-cell line and in the latently infected macrophage cell line. There was no difference in down-regulation by depression status. These studies suggest that an SSRI enhances natural killer/CD8 noncytolytic HIV suppression in HIV/acquired immune deficiency syndrome and decreases HIV viral infectivity of macrophages, ex vivo, suggesting the need for in vivo studies to determine a potential role for agents targeting serotonin in the host defense against HIV.

Understanding the pharmacogenetics of selective serotonin reuptake inhibitors.

Science.gov (United States)

Fabbri, Chiara; Minarini, Alessandro; Niitsu, Tomihisa; Serretti, Alessandro

2014-08-01

The genetic background of antidepressant response represents a unique opportunity to identify biological markers of treatment outcome. Encouraging results alternating with inconsistent findings made antidepressant pharmacogenetics a stimulating but often discouraging field that requires careful discussion about cumulative evidence and methodological issues. The present review discusses both known and less replicated genes that have been implicated in selective serotonin reuptake inhibitors (SSRIs) efficacy and side effects. Candidate genes studies and genome-wide association studies (GWAS) were collected through MEDLINE database search (articles published till January 2014). Further, GWAS signals localized in promising genetic regions according to candidate gene studies are reported in order to assess the general comparability of results obtained through these two types of pharmacogenetic studies. Finally, a pathway enrichment approach is applied to the top genes (those harboring SNPs with p pharmacogenetics, the present review discusses the proposal of moving from the analysis of individual polymorphisms to genes and molecular pathways, and from the separation across different methodological approaches to their combination. Efforts in this direction are justified by the recent evidence of a favorable cost-utility of gene-guided antidepressant treatment.

Does selective serotonin reuptake inhibitor (SSRI) fluoxetine affects mussel Mytilus galloprovincialis?

International Nuclear Information System (INIS)

Gonzalez-Rey, Maria; Bebianno, Maria João

2013-01-01

Fluoxetine (FLX) the active pharmaceutical ingredient (API) in Prozac ® is a widely prescribed psychoactive drug which ubiquitous occurrence in the aquatic environment is associated to a poor removal rate in waste-water treatment plant (WWTP) systems. This API acts as a selective serotonin reuptake inhibitor (SSRI) frequently reported to cause disrupting effects in non-target species. The objective of this study includes a multibiomarker response evaluation on mussel Mytilus galloprovincialis during two weeks exposure to 75 ng L −1 FLX assessing antioxidant enzymes activities – superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST); lipid peroxidation (LPO), acetylcholinesterase (AChE) neurotoxic response and endocrine disruption through alkali-labile phosphates (ALP) indirect measurement of vitellogenin-like proteins. Results show transient tissue-specific enzymatic responses and damage affecting mostly mussel gills. However, the clear ALP levels inhibition throughout time in both sex-differentiated gonads gives evidence to FLX reinforced action as an endocrine disruptor rather than an oxidative or neurotoxic inducer. - Highlights: ► Short-time exposure of Mytilus galloprovincialis to antidepressant fluoxetine. ► Tissue-specific transient antioxidant enzymes activities alteration. ► Lipid peroxidation (LPO) induction in exposed-tissues. ► Acetylcholinesterase (AChE) activity upregulation in exposed gills. ► ALP levels downregulation in exposed sex-differentiated mussels. - Exposure to 75 ng L −1 antidepressant fluoxetine (FLX) induces tissue-specific multibiomarker responses alteration in mussel Mytilus galloprovincialis.

Triple Reuptake Inhibitors: A Premise and Promise

Science.gov (United States)

Marks, David M.; Patkar, Ashwin A.

2008-01-01

On the horizon there is a new class of psychoactive medications which work by inhibiting the neuronal reuptake of serotonin, norepinephrine, and dopamine. There are multiple potential indications for these drugs. Research suggests that they may have a role in treating depressive disorders, and it is plausible they may have potential efficacy in obesity, addiction, and pain syndromes. The current review describes some of the molecules in development presently and explores the research relevant to possible clinical uses for this class of medications. PMID:20046357

Use of dihydro-isobenzofuran in combination with serotonin reuptake inhibitors for CNS disease e.g. depression, anxiety, bipolar disorder, obsessive compulsory disorder

DEFF Research Database (Denmark)

2013-01-01

NOVELTY - For treatment of a CNS disease in a patient, dihydro-isobenzofuran compound (I) in combination with serotonin reuptake inhibitor, is used. USE - For treatment of CNS disease (claimed) including depression, anxiety, bipolar disorder, obsessive compulsory disorder, post traumatic stress d...

Great boast, small roast on effects of selective serotonin reuptake inhibitors

DEFF Research Database (Denmark)

Katakam, Kiran Kumar; Sethi, Naqash Javaid; Jakobsen, Janus Christian

2018-01-01

Our systematic review in BMC Psychiatry concluded that selective serotonin reuptake inhibitors (SSRIs) compared with placebo significantly increase the risk of serious adverse events (SAEs) in patients with major depression and the potential beneficial effects of SSRIs seem to be outweighed...... by the harms. Hieronymus et al. accused us of methodological inaccuracies and blatant errors. In their post-hoc analysis of our data, they reported that SSRIs only increase the risk of SAEs in elderly and seems safe for non-elderly patients. They also found our review misleading because our efficacy analyses...... were based on the 17-item Hamilton Depression Rating Scale; we included suboptimal SSRI doses; and we missed some 'pivotal trials'. We do not agree with Hieronymus et al. regarding several of the 'errors' they claim that we have made. However, we acknowledge that they have identified minor errors...

Inhibitors of serotonin reuptake and specific imipramine binding in human blood plasma

International Nuclear Information System (INIS)

Brusov, O.S.; Fomenko, A.M.; Katasonov, A.B.; Lidemann, R.R.

1985-01-01

This paper describes a method of extraction of endogenous inhibitors of specific IMI binding and of 5-HT reuptake, from human blood plasma and the heterogeneity of these compounds is demonstrated. Specific binding was determined as the difference between binding of 3 H-IMI in the absence and in the presence of 50 microM IMI. Under these conditions, specific binding amounted to 70-80% of total binding of 3 H-IMI. It is shown that extract obtained from human blood contains a material which inhibits dose-dependently both 5-HT reuptake and specific binding of 3 H-IMI. Gel-chromatography of extracts of human blood plasma on Biogel P-2 is also shown

Global gene expression in larval zebrafish (Danio rerio) exposed to selective serotonin reuptake inhibitors (fluoxetine and sertraline) reveals unique expression profiles and potential biomarkers of exposure

International Nuclear Information System (INIS)

Park, June-Woo; Heah, Tze Ping; Gouffon, Julia S.; Henry, Theodore B.; Sayler, Gary S.

2012-01-01

Larval zebrafish (Danio rerio) were exposed (96 h) to selective serotonin reuptake inhibitors (SSRIs) fluoxetine and sertraline and changes in transcriptomes analyzed by Affymetrix GeneChip ® Zebrafish Array were evaluated to enhance understanding of biochemical pathways and differences between these SSRIs. The number of genes differentially expressed after fluoxetine exposure was 288 at 25 μg/L and 131 at 250 μg/L; and after sertraline exposure was 33 at 25 μg/L and 52 at 250 μg/L. Same five genes were differentially regulated in both SSRIs indicating shared molecular pathways. Among these, the gene coding for FK506 binding protein 5, annotated to stress response regulation, was highly down-regulated in all treatments (results confirmed by qRT-PCR). Gene ontology analysis indicated at the gene expression level that regulation of stress response and cholinesterase activities were influenced by these SSRIs, and suggested that changes in transcription of these genes could be used as biomarkers of SSRI exposure. - Highlights: ► Exposure of zebrafish to selective serotonin reuptake inhibitors (SSRIs). ► Fluoxetine and sertraline generate different global gene expression profiles. ► Genes linked to stress response and acetylcholine esterase affected by both SSRIs. - Global gene expression profiles in zebrafish exposed to selective serotonin reuptake inhibitors.

Death and dependence: current controversies over the selective serotonin reuptake inhibitors.

Science.gov (United States)

Nutt, David J

2003-12-01

Recent years have seen a considerable media interest in the adverse effects of the selective serotonin reuptake inhibitors (SSRIs). This has led to claims that these antidepressants may lead to suicide and homicide and that they cause dependence or even addiction. Such claims have caused great concerns to many patients and have confused doctors in both primary care and psychiatric practice. In this article I review the basis of these claims and show that many seem to emerge from the misinterpretation of evidence and the use of imprecise definitions. Although the SSRIs are not free of problems they compare very favourably with other antidepressants and other classes of psychotropic drugs. There is no evidence they are addictive in the formal sense of leading to a drug dependence syndrome. Some suggestions on the way these issues can be more precisely defined and studied in future are given.

Serotonin-induced down-regulation of cell surface serotonin transporter

DEFF Research Database (Denmark)

Jørgensen, Trine Nygaard; Christensen, Peter Møller; Gether, Ulrik

2014-01-01

The serotonin transporter (SERT) terminates serotonergic signaling and enables refilling of synaptic vesicles by mediating reuptake of serotonin (5-HT) released into the synaptic cleft. The molecular and cellular mechanisms controlling SERT activity and surface expression are not fully understood...

Effect of proton pump inhibitors on the serum concentrations of the selective serotonin reuptake inhibitors citalopram, escitalopram, and sertraline.

Science.gov (United States)

Gjestad, Caroline; Westin, Andreas A; Skogvoll, Eirik; Spigset, Olav

2015-02-01

The selective serotonin reuptake inhibitors (SSRIs) citalopram, escitalopram, and sertraline are all metabolized by the cytochrome P-450 isoenzyme CYP2C19, which is inhibited by the proton pump inhibitors (PPIs) omeprazole, esomeprazole, lansoprazole, and pantoprazole. The aim of the present study was to evaluate the effect of these PPIs on the serum concentrations of citalopram, escitalopram, and sertraline. Serum concentrations from patients treated with citalopram, escitalopram, or sertraline were obtained from a routine therapeutic drug monitoring database, and samples from subjects concomitantly using PPIs were identified. Dose-adjusted SSRI serum concentrations were calculated to compare data from those treated and those not treated with PPIs. Citalopram concentrations were significantly higher in patients treated with omeprazole (+35.3%; P Escitalopram concentrations were significantly higher in patients treated with omeprazole (+93.9%; P escitalopram is affected to a greater extent than are citalopram and sertraline. When omeprazole or esomeprazole are used in combination with escitalopram, a 50% dose reduction of the latter should be considered.

Simultaneous initiation (coinitiation) of pharmacotherapy with triiodothyronine and a selective serotonin reuptake inhibitor for major depressive disorder: a quantitative synthesis of double-blind studies

NARCIS (Netherlands)

Papakostas, George I.; Cooper-Kazaz, Rena; Appelhof, Bente C.; Posternak, Michael A.; Johnson, Daniel P.; Klibanski, Anne; Lerer, Bernard; Fava, Maurizio

2009-01-01

To examine the efficacy and overall tolerability of the simultaneous initiation of treatment (coinitiation) with triiodothyronine (T3) and a selective serotonin reuptake inhibitor (SSRI) for major depressive disorder (MDD). Sources of date were Medline/Pubmed, EMBASE, the Cochrane database, and

Treatment of selective mutism: focus on selective serotonin reuptake inhibitors.

Science.gov (United States)

Kaakeh, Yaman; Stumpf, Janice L

2008-02-01

Abstract Selective mutism is a pediatric psychiatric disorder that occurs when a child consistently fails to speak in specific situations in which speaking is expected, such as at school and social gatherings, but speaks appropriately in other settings. Selective mutism often is diagnosed when a child starts school and does not talk to teachers or peers, but talks to family members at home; the condition is frequently accompanied by anxiety and shyness. Although the underlying etiology of the condition remains unclear, psychotherapy is the preferred initial treatment, with the support of parents and teachers. If the child does not respond to psychotherapy, addition of pharmacologic treatment should be considered, depending on the severity of symptoms and presence of other illnesses. Although data are limited to case reports and trials with small patient populations and short follow-up periods, some patients with selective mutism respond to therapy with selective serotonin reuptake inhibitors (SSRIs). Fluoxetine is the most studied SSRI as treatment for the condition, although further investigation is required to determine the optimal dosage and duration of therapy.

Exposure to selective serotonin reuptake inhibitors and the risk of congenital malformations

DEFF Research Database (Denmark)

Solem, Espen Victor Jimenez; Andersen, Jon Thor Trærup; Petersen, Morten

2012-01-01

Objectives:To analyse the relation between selective serotonin reuptake inhibitor (SSRI) use and major congenital malformations, with focus on malformations of the heart. DESIGN: Register-based retrospective nationwide cohort study, using the Danish Medical Birth Registry. SETTING: Denmark...... exposure during pregnancy. RESULTS: The authors identified 848¿786 pregnancies; 4183 were exposed to an SSRI throughout the first trimester and 806 pregnancies paused exposure during pregnancy. Risks of congenital malformations of the heart were similar for pregnancies exposed to an SSRI throughout...... the first trimester, adjusted OR 2.01 (95% CI 1.60 to 2.53), and for pregnancies with paused SSRI treatment during pregnancy, adjusted OR 1.85 (95% CI 1.07 to 3.20), p value for difference: 0.94. The authors found similar increased risks of specific congenital malformations of the heart for the individual...

Combined Norepinephrine / Serotonergic Reuptake Inhibition: Effects on Maternal Behavior, Aggression and Oxytocin in the Rat

Directory of Open Access Journals (Sweden)

Elizabeth Thomas Cox

2011-06-01

Full Text Available BACKGROUND: Few systematic studies exist on the effects of chronic reuptake of monoamine neurotransmitter systems during pregnancy on the regulation of maternal behavior, although many drugs act primarily through one or more of these systems. Previous studies examining fluoxetine and amfonelic acid treatment during gestation on subsequent maternal behavior in rodents indicated significant alterations in postpartum maternal care, aggression and oxytocin levels. In this study, we extended our studies to include chronic gestational treatment with desipramine or amitriptyline to examine differential effects of reuptake inhibition of norepinephrine and combined noradrenergic and serotonergic systems on maternal behavior, aggression, and oxytocin system changes. METHODS: Pregnant Sprague-Dawley rats were treated throughout gestation with saline or one of three doses of either desipramine, which has a high affinity for the norepinephrine monoamine transporter, or amitriptyline, an agent with high affinity for both the norepinephrine and serotonin monoamine transporters. Maternal behavior and postpartum aggression were assessed on postpartum days one and six respectively. Oxytocin levels were measured in relevant brain regions on postpartum day seven. Predictions were that amitriptyline would decrease maternal behavior and increase aggression relative to desipramine, particularly at higher doses. Amygdaloidal oxytocin was expected to decrease with increased aggression. RESULTS: Amitriptyline and desiprimine differentially reduced maternal behavior, and at higher doses reduced aggressive behavior. Hippocampal oxytocin levels were lower after treatment with either drug but were not correlated with specific behavioral effects. These results, in combination with previous findings following gestational treatment with other selective neurotransmitter reuptake inhibitors, highlight the diverse effects of multiple monoamine systems thought to be involved in

Interferon and ribavarin associated depression in hcv patients and role of selective serotonin reuptake inhibitors

International Nuclear Information System (INIS)

Bashir, K.; Hussain, C.A.; Amer, K.

2013-01-01

Objective: To determine the frequency and severity of depression associated with antiviral therapy of Hepatitis C Virus (HCV) infection and effect of selective serotonin reuptake Inhibitors (SSRIs) to treat these depressive symptoms. Type of Study: Observational Analytical study. Place of Study and Duration: The study was conducted at Psychiatry, Medicine and Pathology department of Combined Military Hospital Sialkot Pakistan from February 2009 to July 2010. Subjects and Methods: All the patients in this study were suffering from HCV infection and were managed with Interferon (3 m.i.u. s/c thrice weekly) and Cap Ribavirin (400 mg bid) for six months. Patients were assessed by Hospital Anxiety and Depression Scale (HADS) - Urdu Version and Beck's Depressive Inventory (BDI) Scores after twelve weeks of antiviral therapy. Depressed patients were managed with selective serotonin reuptake inhibitors (SSRIs) for six weeks and again evaluated on HADS and BDI Scores. Response to SSRIs was defined as complete response, partial response and no response. Results: A total of 105 patients were studied out of which 75 were male and 30 were female with mean age 29.4 years. Out of these 54 (51.43%) patients developed depression and this tendency to develop depression was not related with the age and sex of the patients. The mean HADS and BDI scores before and after treatments with SSRIs were compared for significance and it was quite significant. There was not a single patient who did not show response to SSRIs. Conclusion: Depression is frequently associated with antiviral therapy of HCV RNA viraemia with interferon and SSRIs have proved an effective and safe remedy in these patients. (author)

Non-tricyclic and Non-selective Serotonin Reuptake Inhibitor Antidepressants and Recurrent Falls in Frail Older Women.

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Naples, Jennifer G; Kotlarczyk, Mary P; Perera, Subashan; Greenspan, Susan L; Hanlon, Joseph T

2016-12-01

To determine the risk of recurrent falls associated with antidepressants other than tricyclics (TCAs) and selective serotonin reuptake inhibitors (SSRIs) among frail older women. This is a secondary analysis of the Zoledronic acid in frail Elders to STrengthen bone, or ZEST, trial data treated as a longitudinal cohort in 181 frail, osteoporotic women aged ≥65 years in long-term care. The primary exposure was individual non-TCA/non-SSRI antidepressants (i.e., serotonin norepinephrine reuptake inhibitors, mirtazapine, trazodone, and bupropion) at baseline and 6 months. The main outcome was recurrent (at least two) falls within 6 months after antidepressant exposure. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were derived using a generalized estimating equations model. At least 15% of women experienced recurrent falls between 0-6 and 6-12 months. At baseline and 6 months, 18.2% and 6.9% had a non-TCA/non-SSRI antidepressant, respectively. Adjusting for demographics, health status, and other drugs that increase risk of falls, non-TCA/non-SSRI antidepressant exposure significantly increased the risk of recurrent falls (AOR: 2.14; 95% CI: 1.01-4.54). Fall risk further increased after removing bupropion from the non-TCA/non-SSRI antidepressant group in sensitivity analyses (AOR: 2.73; 95% CI: 1.24-6.01). Other antidepressant classes may not be safer than TCAs/SSRIs with respect to recurrent falls in frail older women. Copyright © 2016 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Dependence and withdrawal reactions to benzodiazepines and sellective serotonin reuptake inhibitors: How did the health authorities react?

DEFF Research Database (Denmark)

Nielsen, Margrethe

2013-01-01

AIM: Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time. METHODS: Documentary study. We searched the web-sites of the European Medicines Agency and the drug agencies in USA...... it is difficult for many patients to stop treatment. In the perspective of a precautionary principle, drug agencies have failed to acknowledge that SSRIs can cause dependence and have minimised the problem with regard to its frequency and severity. In the perspective of a risk management principle, the drug...

Possible role of selective serotonin reuptake inhibitor sertraline on oxidative stress responses.

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Battal, D; Yalin, S; Eker, E D; Aktas, A; Sahin, N O; Cebo, M; Berköz, M

2014-01-01

The naphthylamine derivative sertraline is a potent and selective inhibitor of serotonin reuptake into presynaptic terminals and the most widely used that has been shown to have both antidepressant and antianxiety effects. In the present study the possible role of sertraline (acute and chronically doses) was evaluated on lipid peroxidation levels and antioxidant enzyme activities in plasma and brain tissues of (10, 40, 80 mg/kg) sertraline treated Wistar albino rats (n=48). Lipid peroxidation levels (MDA) of plasma and brain tissue increased in all acute and chronic sertraline treated rats (p Catalase (CAT) levels of plasma and brain tissue and paraoxonase (PON) levels of plasma decreased (p < 0.05) as compared with vehicle group. Based on the data, it can be concluded that high dose sertraline administration enhances oxidative stress. Therefore, dose adjustment in depression patients seems significant as it may help prevention of further prognosis of the diseases.

A role for the serotonin reuptake transporter in the brain and intestinal features of autism spectrum disorders and developmental antidepressant exposure.

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Margolis, Kara Gross

2017-10-01

Many disease conditions considered CNS-predominant harbor significant intestinal comorbidities. Serotonin (5-HT) and the serotonin reuptake transporter (SERT) have increasingly been shown to play important roles in both brain and intestinal development and long-term function. 5-HT and SERT may thus modulate critical functions in the development and perpetuation of brain-gut axis disease. We discuss the potential roles of 5-HT and SERT in the brain and intestinal manifestations of autism spectrum disorders and developmental antidepressant exposure. The potential therapeutic value of 5-HT 4 modulation in the subsequent treatment of these conditions is also addressed. Copyright © 2017 Elsevier B.V. All rights reserved.

Rate of improvement during and across three treatments for panic disorder with or without agoraphobia : Cognitive behavioral therapy, selective serotonin reuptake inhibitor or both combined

NARCIS (Netherlands)

Van Apeldoorn, Franske J.; Van Hout, Wiljo J. P. J.; Timmerman, Marieke E.; Mersch, Peter Paul A.; den Boer, Johan A.

2013-01-01

Background: Existing literature on panic disorder (PD) yields no data regarding the differential rates of improvement during Cognitive Behavioral Therapy (CBT), Selective Serotonin Reuptake Inhibitor (SSRI) or both combined (CBT+SSRI). Method: Patients were randomized to CBT, SSRI or CBT+SSRI which

17β-Estradiol augments antidepressant efficacy of escitalopram in ovariectomized rats: Neuroprotective and serotonin reuptake transporter modulatory effects.

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Ibrahim, Weam W; Safar, Marwa M; Khattab, Mahmoud M; Agha, Azza M

2016-12-01

The prevalence or recurrence of depression is seriously increased in women during the transition to and after menopause. The chronic hypo-estrogenic state of menopause may reduce the response to antidepressants; however the influence of estrogen therapy on their efficacy is still controversial. This study aimed at investigating the effects of combining escitalopram with 17β-estradiol on depression and cognitive impairment induced by ovariectomy, an experimental model of human menopause. Young adult female Wistar rats were subjected to either sham operation or ovariectomy. Ovariectomized animals were treated chronically with escitalopram (10mg/kg/day, i.p) alone or with four doses of 17β-estradiol (40μg/kg, s.c) given prior to the behavioral tests. Co-administration of 17β-estradiol improved escitalopram-induced antidepressant effect in forced swimming test verified as more prominent decrease in the immobility time without opposing its memory enhancing effect in Morris water maze. 17β-estradiol augmented the modulatory effects of escitalopram on the hippocampal levels of brain-derived neurotrophic factor and serotonin reuptake transporter as well as tumor necrosis factor-alpha without altering its effects on the gene expressions of serotonin receptor 1A, estrogen receptors alpha and beta, or acetylcholinestearase content. This combined therapy afforded synergistic protective effects on the brain histopathological architecture, particularly, the hippocampus. The antidepressant effect of 17β-estradiol was abolished by pretreatment with estrogen receptor antagonist, tamoxifen (10mg/kg, p.o). In conclusion, 17β-estradiol-induced antidepressant effect was confined to intracellular estrogen receptors activation. Moreover, 17β-estradiol enhanced escitalopram's efficiency in ameliorating menopausal-like depression, via exerting synergistic neuroprotective and serotonin reuptake transporter modulatory effects, without impeding escitalopram-mediated cognitive

In vivo imaging of cerebral serotonin transporter and serotonin(2A) receptor binding in 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") and hallucinogen users

DEFF Research Database (Denmark)

Erritzoe, David; Frøkjær, Vibe; Holst, Klaus K

2011-01-01

Both hallucinogens and 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") have direct agonistic effects on postsynaptic serotonin(2A) receptors, the key site for hallucinogenic actions. In addition, MDMA is a potent releaser and reuptake inhibitor of presynaptic serotonin.......Both hallucinogens and 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") have direct agonistic effects on postsynaptic serotonin(2A) receptors, the key site for hallucinogenic actions. In addition, MDMA is a potent releaser and reuptake inhibitor of presynaptic serotonin....

Reduction of intraspecific aggression in adult rats by neonatal treatment with a selective serotonin reuptake inhibitor

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Manhães de Castro R.

2001-01-01

Full Text Available Most studies suggest that serotonin exerts an inhibitory control on the aggression process. According to experimental evidence, this amine also influences growth and development of the nervous tissue including serotoninergic neurons. Thus, the possibility exists that increased serotonin availability in young animals facilitates a long-lasting effect on aggressive responses. The present study aimed to investigate the aggressive behavior of adult rats (90-120 days treated from the 1st to the 19th postnatal day with citalopram (CIT, a selective serotonin reuptake inhibitor (20 mg/kg, sc, every 3 days. Aggressive behavior was induced by placing a pair of rats (matched by weight in a box (20 x 20 x 20 cm, and submitting them to a 20-min session of electric footshocks (five 1.6-mA - 2-s current pulses, separated by a 4-min intershock interval. When compared to the control group (rats treated for the same period with equivalent volumes of saline solution, the CIT group presented a 41.4% reduction in the duration of aggressive response. The results indicate that the repeated administration of CIT early in life reduces the aggressive behavior in adulthood and suggest that the increased brain serotoninergic activity could play a role in this effect.

Development of norepinephrine transporter reuptake inhibition assays using SK-N-BE(2C cells

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Ann M. Decker

2018-05-01

Full Text Available This report describes efforts to develop and validate novel norepinephrine transporter reuptake inhibition assays using human neuroblastoma SK-N-BE(2C cells in 24-well format. Before conducting the assays, the SK-N-BE(2C cells were first evaluated for their ability to uptake [3H]norepinephrine and were shown to have a saturable uptake with a KM value of 416 nM. Using this determined KM value, reuptake inhibition assays were then conducted with a variety of ligands including antidepressants, as well as piperazine and phenyltropane derivatives. The results obtained with the SK-N-BE(2C cells indicate that this model system can detect a range of ligand potencies, which compare well with other established transporter assays. Our data suggest that SK-N-BE(2C cells have potential utility to serve as another model system to detect norepinephrine reuptake inhibition activity.

Selective serotonin reuptake inhibitors and intraoperative blood pressure.

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van Haelst, Ingrid M M; van Klei, Wilton A; Doodeman, Hieronymus J; Kalkman, Cor J; Egberts, Toine C G

2012-02-01

The influence of selective serotonin reuptake inhibitors (SSRIs) on blood pressure is poorly understood. We hypothesized that if SSRIs have an influence on blood pressure, this might become manifest in changes in intraoperative blood pressure. We aimed to study the association between perioperative use of SSRIs and changes in intraoperative blood pressure by measuring the occurrence of intraoperative hyper- and hypotension. We conducted a retrospective observational follow-up study among patients who underwent elective primary total hip arthroplasty. The index group included users of SSRIs. The reference group included a random sample (ratio 1:3) of nonusers of an antidepressant agent. The outcome was the occurrence of intraoperative hypo- and hypertensive episodes (number, mean and total duration, and area under the curve (AUC)). The outcome was adjusted for confounding factors using regression techniques. The index group included 20 users of an SSRI. The reference group included 60 nonusers. Users of SSRIs showed fewer intraoperative hypotensive episodes, a shorter mean and total duration, and a smaller AUC when compared to the reference group. After adjustment for confounders, SSRI use was associated with a significantly shorter total duration of hypotension: mean difference of -29.4 min (95% confidence interval (CI) -50.4 to -8.3). Two users of an SSRI and two patients in the reference group had a hypertensive episode. Continuation of treatment with SSRIs before surgery was associated with a briefer duration of intraoperative hypotension.

Risk of preeclampsia after gestational exposure to selective serotonin reuptake inhibitors and other antidepressants: A study from The Norwegian Mother and Child Cohort Study.

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Lupattelli, Angela; Wood, Mollie; Lapane, Kate; Spigset, Olav; Nordeng, Hedvig

2017-10-01

To describe the risk of early- and late-onset preeclampsia across pregnancies exposed to antidepressants and to evaluate the impact of timing and length of gestational exposure to antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs), on preeclampsia. The Norwegian Mother and Child Cohort, a prospective population-based study, and the Medical Birth Registry of Norway provided information on antidepressant exposure, depression, and anxiety symptoms in pregnancy, preeclampsia diagnoses, and important covariates. Within a pregnancy cohort of depressed women, we compared the risk of late-onset preeclampsia between SSRI-exposed and nonmedicated pregnancies using marginal structural models (weighted) and modified Poisson regression models. Of the 5887 pregnancies included, 11.1% were exposed at any time before week 34 to SSRIs, 1.3% to serotonin-norepinephrine reuptake inhibitors, 0.4% to tricyclic antidepressants, and 0.5% to other antidepressants. The risks of early- and late-onset preeclampsia by exposure status in pregnancy were 0.3% and 3.6% (nonmedicated), 0.4% and 3.7% (SSRIs), 1.5% and 4.1% (serotonin-norepinephrine reuptake inhibitors), and 7.1% and 10.0% (tricyclic antidepressants). Compared with nonmedicated pregnancies, SSRI-exposed in mid and late gestation had adjusted relative risks for late-onset mild preeclampsia of 0.76 (95% confidence interval, 0.38-1.53) and 1.56 (0.71-3.44) (weighted models), respectively. There was no association between SSRI exposure in pregnancy and severe late-onset preeclampsia. We have provided evidence that SSRI use in early and midpregnancy does not substantially increase the risk of late-onset preeclampsia. © 2017 The Authors. Pharmacoepidemiology & Drug Safety published by John Wiley & Sons Ltd.

The selective serotonin reuptake inhibitor fluoxetine does not change rectal sensitivity and symptoms in patients with irritable bowel syndrome: a double blind, randomized, placebo-controlled study

NARCIS (Netherlands)

Kuiken, Sjoerd D.; Tytgat, Guido N. J.; Boeckxstaens, Guy E. E.

2003-01-01

BACKGROUND & AIMS: Although widely prescribed, the evidence for the use of antidepressants for the treatment of irritable bowel syndrome (IBS) is limited. In this study, we hypothesized that fluoxetine (Prozac), a selective serotonin reuptake inhibitor, has visceral analgesic properties, leading to

In Vivo Imaging of Cerebral Serotonin Transporter and Serotonin(2A) Receptor Binding in 3,4-Methylenedioxymethamphetamine (MDMA or "Ecstasy") and Hallucinogen Users

DEFF Research Database (Denmark)

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

2011-01-01

Context: Both hallucinogens and 3,4-methylenedioxy-methamphetamine( MDMA or "ecstasy") have direct agonistic effects on postsynaptic serotonin(2A) receptors, the key site for hallucinogenic actions. In addition, MDMA is a potent releaser and reuptake inhibitor of presynaptic serotonin.Objective: ......Context: Both hallucinogens and 3,4-methylenedioxy-methamphetamine( MDMA or "ecstasy") have direct agonistic effects on postsynaptic serotonin(2A) receptors, the key site for hallucinogenic actions. In addition, MDMA is a potent releaser and reuptake inhibitor of presynaptic serotonin...

Pharmacological Characterization of H05, a Novel Serotonin and Noradrenaline Reuptake Inhibitor with Moderate 5-HT2A Antagonist Activity for the Treatment of Depression.

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Xu, Xiangqing; Wei, Yaqin; Guo, Qiang; Zhao, Song; Liu, Zhiqiang; Xiao, Ting; Liu, Yani; Qiu, Yinli; Hou, Yuanyuan; Zhang, Guisen; Wang, KeWei

2018-06-01

Multitarget antidepressants selectively inhibiting monoaminergic transporters and 5-hydroxytryptamine (5-HT) 2A receptor have demonstrated higher efficacy and fewer side effects than selective serotonin reuptake inhibitors. In the present study, we synthesized a series of novel 3-(benzo[d][1,3]dioxol-4-yloxy)-3-arylpropyl amine derivatives, among which compound H05 was identified as a lead, exhibiting potent inhibitory effects on both serotonin ( K i = 4.81 nM) and norepinephrine (NE) ( K i = 6.72 nM) transporters and moderate 5-HT 2A antagonist activity (IC 50 = 60.37 nM). H05 was able to dose-dependently reduce the immobility duration in mouse forced swimming test and tail suspension test, with the minimal effective doses lower than those of duloxetine, and showed no stimulatory effect on locomotor activity. The administration of H05 (5, 10, and 20 mg/kg, by mouth) significantly shortened the immobility time of adrenocorticotropin-treated rats that serve as a model of treatment-resistant depression, whereas imipramine (30 mg/kg, by mouth) and duloxetine (30 mg/kg, by mouth) showed no obvious effects. Chronic treatment with H05 reversed the depressive-like behaviors in a rat model of chronic unpredictable mild stress and a mouse model of corticosterone-induced depression. Microdialysis analysis revealed that the administration of H05 at either 10 or 20 mg/kg increased the release of 5-HT and NE from the frontal cortex. The pharmacokinetic (PK) and brain penetration analyses suggest that H05 has favorable PK properties with good blood-brain penetration ability. Therefore, it can be concluded that H05, a novel serotonin and NE reuptake inhibitor with 5-HT 2A antagonist activity, possesses efficacious activity in the preclinical models of depression and treatment-resistant depression, and it may warrant further evaluation for clinical development. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

A chiral synthesis of dapoxetine hydrochloride, a serotonin re-uptake inhibitor, and its 14C isotopomer

International Nuclear Information System (INIS)

Wheeler, W.J.; O'Bannon, D.D.

1992-01-01

The 14 C-isotopmer of dapoxetine-[ 14 C] HCl (S (+) -N,N-dimethyl-α[2-(1-naphthalenyloxy)ethyl-2- 14 C]benzenemeth a-n amine hydrochloride, 1a), a potent serotonin re-uptake inhibitor has been prepared by a chiral synthesis, starting with tert. -butyloxyphenylglycine (3). Borane reduction, followed by activation of the resulting alcohol 4 as its mesylate 5b, provided the chiral starting material. The radiolabel was introduced by reaction of 5b with sodium cyanide-[ 14 C]. The desired product (1) was then elaborated from nitrile 6a,b via a five step synthesis in an overall 19.5% radiochemical yield. (Author)

Sexual side effects of serotonergic antidepressants: mediated by inhibition of serotonin on central dopamine release?

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Bijlsma, Elisabeth Y; Chan, Johnny S W; Olivier, Berend; Veening, Jan G; Millan, Mark J; Waldinger, Marcel D; Oosting, Ronald S

2014-06-01

Antidepressant-induced sexual dysfunction adversely affects the quality of life of antidepressant users and reduces compliance with treatment. Animal models provide an instructive approach for examining potential sexual side effects of novel drugs. This review discusses the stability and reproducibility of our standardized test procedure that assesses the acute, subchronic and chronic effects of psychoactive compounds in a 30 minute mating test. In addition, we present an overview of the effects of several different (putative) antidepressants on male rat sexual behavior, as tested in our standardized test procedure. By comparing the effects of these mechanistically distinct antidepressants (paroxetine, venlafaxine, bupropion, buspirone, DOV 216,303 and S32006), this review discusses the putative mechanism underlying sexual side effects of antidepressants and their normalization. This review shows that sexual behavior is mainly inhibited by antidepressants that increase serotonin neurotransmission via blockade of serotonin transporters, while those that mainly increase the levels of dopamine and noradrenaline are devoid of sexual side effects. Those sexual disturbances cannot be normalized by simultaneously increasing noradrenaline neurotransmission, but are normalized by increasing both noradrenaline and dopamine neurotransmission. Therefore, it is hypothesized that the sexual side effects of selective serotonin reuptake inhibitors may be mediated by their inhibitory effects on dopamine signaling in sex brain circuits. Clinical development of novel antidepressants should therefore focus on compounds that simultaneously increase both serotonin and dopamine signaling. © 2013 Elsevier Inc. All rights reserved.

Comparison of the effects of sibutramine and other monoamine reuptake inhibitors on food intake in the rat

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Jackson, Helen C; Needham, Andrew M; Hutchins, Lisa J; Mazurkiewicz, Sarah E; Heal, David J

1997-01-01

The effects of the potent 5-hydroxytryptamine (5-HT) and noradrenaline reuptake inhibitor (serotonin-noradrenaline reuptake inhibitor, SNRI), sibutramine, on the cumulative food intake of freely-feeding male Sprague-Dawley rats during an 8 h dark period were investigated and compared to those of the selective 5-HT reuptake inhibitor (selective serotonin reuptake inhibitor, SSRI), fluoxetine; the selective noradrenaline reuptake inhibitor, nisoxetine; the 5-HT and noradrenaline reuptake inhibitors, venlafaxine and duloxetine; and the 5-HT releaser and 5-HT reuptake inhibitor, (+)-fenfluramine. Sibutramine (3 and 10 mg kg−1, p.o.) and (+)-fenfluramine (1 and 3 mg kg−1, p.o.) produced a significant, dose-dependent decrease in food intake over the 8 h dark period. These responses became apparent within the first 2 h following drug administration. Fluoxetine (3, 10 and 30 mg kg−1, p.o.), and nisoxetine (3, 10 and 30 mg kg−1, p.o.) had no significant effect on food intake during the 8 h dark period. However, a combination of fluoxetine and nisoxetine (30 mg kg−1, p.o., of each) significantly decreased food intake 2 and 8 h after drug administration. Venlafaxine (100 and 300 mg kg−1, p.o.) and duloxetine (30 mg kg−1, p.o.) also significantly decreased food intake in the 2 and 8 h following drug administration. The results of this study demonstrate that inhibition of 5-HT and noradrenaline reuptake by sibutramine, venlafaxine, duloxetine, or by a combination of fluoxetine and nisoxetine, markedly reduces food intake in freely-feeding rats and suggest that this may be a novel approach for the treatment of obesity. PMID:9283714

Characterization of the effects of serotonin on the release of [3H]dopamine from rat nucleus accumbens and striatal slices

International Nuclear Information System (INIS)

Nurse, B.; Russell, V.A.; Taljaard, J.J.

1988-01-01

The effect of serotonin agonists on the depolarization (K+)-induced, calcium-dependent, release of [ 3 H]dopamine (DA) from rat nucleus accumbens and striatal slices was investigated. Serotonin enhanced basal 3 H overflow and reduced K+-induced release of [ 3 H]DA from nucleus accumbens slices. The effect of serotonin on basal 3 H overflow was not altered by the serotonin antagonist, methysergide, or the serotonin re-uptake blocker, chlorimipramine, but was reversed by the DA re-uptake carrier inhibitors nomifensine and benztropine. With the effect on basal overflow blocked, serotonin did not modulate K+-induced release of [ 3 H]DA in the nucleus accumbens or striatum. The serotonin agonists, quipazine (in the presence of nomifensine) and 5-methoxytryptamine, did not significantly affect K+-induced release of [ 3 H]DA in the nucleus accumbens. This study does not support suggestions that serotonin receptors inhibit the depolarization-induced release of dopamine in the nucleus accumbens or striatum of the rat brain. The present results do not preclude the possibility that serotonin may affect the mesolimbic reward system at a site which is post-synaptic to dopaminergic terminals in the nucleus accumbens

Selective serotonin reuptake inhibitors potentiate the rapid antidepressant-like effects of serotonin4 receptor agonists in the rat.

Directory of Open Access Journals (Sweden)

Guillaume Lucas

2010-02-01

Full Text Available We have recently reported that serotonin(4 (5-HT(4 receptor agonists have a promising potential as fast-acting antidepressants. Here, we assess the extent to which this property may be optimized by the concomitant use of conventional antidepressants.We found that, in acute conditions, the 5-HT(4 agonist prucalopride was able to counteract the inhibitory effect of the selective serotonin reuptake inhibitors (SSRI fluvoxamine and citalopram on 5-HT neuron impulse flow, in Dorsal Raphé Nucleus (DRN cells selected for their high (>1.8 Hz basal discharge. The co-administration of both prucalopride and RS 67333 with citalopram for 3 days elicited an enhancement of DRN 5-HT neuron average firing rate, very similar to what was observed with either 5-HT(4 agonist alone. At the postsynaptic level, this translated into the manifestation of a tonus on hippocampal postsynaptic 5-HT(1A receptors, that was two to three times stronger when the 5-HT(4 agonist was combined with citalopram. Similarly, co-administration of citalopram synergistically potentiated the enhancing effect of RS 67333 on CREB protein phosphorylation within the hippocampus. Finally, in the Forced Swimming Test, the combination of RS 67333 with various SSRIs (fluvoxamine, citalopram and fluoxetine was more effective to reduce time of immobility than the separate administration of each compound.These findings strongly suggest that the adjunction of an SSRI to a 5-HT(4 agonist may help to optimize the fast-acting antidepressant efficacy of the latter.

Serum Prolactin Levels in Patients with Major Depressive Disorder Receiving Selective Serotonin-Reuptake Inhibitor Monotherapy for 3 Months: A Prospective Study

OpenAIRE

Park, Young-Min

2017-01-01

Objective It is unclear whether selective serotonin-reuptake inhibitors (SSRIs) can significantly increase the prolactin level. The purpose of this study was to identify the relationship between the prolactin level and the administration of SSRIs such as escitalopram and sertraline. An additional purpose was to determine whether the elevation of prolactin differs between escitalopram and sertraline treatment. Methods Serum prolactin levels were measured at baseline and after 3 months in 23 pa...

Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) for the prevention of tension-type headache in adults.

Science.gov (United States)

Banzi, Rita; Cusi, Cristina; Randazzo, Concetta; Sterzi, Roberto; Tedesco, Dario; Moja, Lorenzo

2015-05-01

This is an updated version of the Cochrane review published in 2005 on selective serotonin re-uptake inhibitors (SSRIs) for preventing migraine and tension-type headache. The original review has been split in two parts and this review now only regards tension-type headache prevention. Another updated review covers migraine. Tension-type headache is the second most common disorder worldwide and has high social and economic relevance. As serotonin and other neurotransmitters may have a role in pain mechanisms, SSRIs and serotonin-norepinephrine reuptake inhibitors (SNRIs) have been evaluated for the prevention of tension-type headache. To determine the efficacy and tolerability of SSRIs and SNRIs compared to placebo and other active interventions in the prevention of episodic and chronic tension-type headache in adults. For the original review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL 2003, Issue 4), MEDLINE (1966 to January 2004), EMBASE (1994 to May 2003), and Headache Quarterly (1990 to 2003). For this update, we revised the original search strategy to reflect the broader type of intervention (SSRIs and SNRIs). We searched CENTRAL (2014, Issue 10) on the Cochrane Library, MEDLINE (1946 to November 2014), EMBASE (1980 to November 2014), and PsycINFO (1987 to November 2014). We also checked the reference lists of retrieved articles and searched trial registries for ongoing trials. We included randomised controlled trials comparing SSRIs or SNRIs with any type of control intervention in participants 18 years and older, of either sex, with tension-type headache. Two authors independently extracted data (headache frequency, index, intensity, and duration; use of symptomatic/analgesic medication; quality of life; and withdrawals) and assessed the risk of bias of trials. The primary outcome is tension-type headache frequency, measured by the number of headache attacks or the number of days with headache per evaluation period. The original

Common selective serotonin reuptake inhibitor side effects in older adults associated with genetic polymorphisms in the serotonin transporter and receptors: data from a randomized controlled trial.

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Garfield, Lauren D; Dixon, David; Nowotny, Petra; Lotrich, Francis E; Pollock, Bruce G; Kristjansson, Sean D; Doré, Peter M; Lenze, Eric J

2014-10-01

Antidepressant side effects are a significant public health issue, associated with poor adherence, premature treatment discontinuation, and, rarely, significant harm. Older adults assume the largest and most serious burden of medication side effects. We investigated the association between antidepressant side effects and genetic variation in the serotonin system in anxious, older adults participating in a randomized, placebo-controlled trial of the selective serotonin reuptake inhibitor (SSRI) escitalopram. Adults (N = 177) aged ≥ 60 years were randomized to active treatment or placebo for 12 weeks. Side effects were assessed using the Udvalg fur Kliniske Undersøgelser side-effect rating scale. Genetic polymorphisms were putative functional variants in the promoters of the serotonin transporter and 1A and 2A receptors (5-HTTLPR [L/S + rs25531], HTR1A rs6295, HTR2A rs6311, respectively). Four significant drug-placebo side-effect differences were found: increased duration of sleep, dry mouth, diarrhea, and diminished sexual desire. Analyses using putative high- versus low-transcription genotype groupings revealed six pharmacogenetic effects: greater dry mouth and decreased sexual desire for the low- and high-expressing serotonin transporter genotypes, respectively, and greater diarrhea with the 1A receptor low-transcription genotype. Diminished sexual desire was experienced significantly more by high-expressing genotypes in the serotonin transporter, 1A, or 2A receptors. There was not a significant relationship between drug concentration and side effects nor a mean difference in drug concentration between low- and high-expressing genotypes. Genetic variation in the serotonin system may predict who develops common SSRI side effects and why. More work is needed to further characterize this genetic modulation and to translate research findings into strategies useful for more personalized patient care. Published by Elsevier Inc.

Action potential-independent and pharmacologically unique vesicular serotonin release from dendrites

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Colgan, Lesley A.; Cavolo, Samantha L.; Commons, Kathryn G.; Levitan, Edwin S.

2012-01-01

Serotonin released within the dorsal raphe nucleus (DR) induces feedback inhibition of serotonin neuron activity and consequently regulates mood-controlling serotonin release throughout the forebrain. Serotonin packaged in vesicles is released in response to action potentials by the serotonin neuron soma and terminals, but the potential for release by dendrites is unknown. Here three-photon (3P) microscopy imaging of endogenous serotonin in living rat brain slice, immunofluorescence and immuno-gold electron microscopy detection of VMAT2 (vesicular monoamine transporter 2) establish the presence of vesicular serotonin within DR dendrites. Furthermore, activation of glutamate receptors is shown to induce vesicular serotonin release from dendrites. However, unlike release from the soma and terminals, dendritic serotonin release is independent of action potentials, relies on L-type Ca2+ channels, is induced preferentially by NMDA, and displays distinct sensitivity to the selective serotonin reuptake inhibitor (SSRI) antidepressant fluoxetine. The unique control of dendritic serotonin release has important implications for DR physiology and the antidepressant action of SSRIs, dihydropyridines and NMDA receptor antagonists. PMID:23136413

Exposure to Selective Serotonin Reuptake Inhibitors in Early Pregnancy and the Risk of Miscarriage

DEFF Research Database (Denmark)

Andersen, Jon Thor Trærup; Andersen, Nadia Lyhne; Horwitz, Henrik

2014-01-01

OBJECTIVE: To investigate whether exposure to selective serotonin reuptake inhibitors (SSRIs) in early pregnancy is associated with miscarriage. METHODS: This was a nationwide cohort study identifying all registered pregnancies in Denmark from 1997 to 2010. All births were identified using...... the Medical Birth Registry, and all records of induced abortion or miscarriage were gathered from the National Hospital Register. Data on SSRI use were gathered from the National Prescription Register. Cox proportional hazard regression models were used to calculate the hazard of miscarriage in women exposed...... to an SSRI in early pregnancy and the hazard of miscarriage in women discontinuing treatment before pregnancy. RESULTS: We identified 1,279,840 pregnancies (911,569 births, 142,093 miscarriages, 226,178 induced abortions). Of the 22,884 exposed to an SSRI during the first 35 days of pregnancy, 12.6% (2...

Morphological changes of intestinal mucosa in patients with different clinical variants of irritable bowel syndrome using tetracyclic antidepressants and selective serotonin reuptake inhibitor

OpenAIRE

Nagieva S.; Svintsitskyy A.; Kuryk O.; Korendovych I.

2015-01-01

Objective. To assess histological changes of colonic mucosa in patients with clinically different types of irritable bowel syndrome (IBS) before and after the treatment with tetracyclic antidepressant and selective serotonin reuptake inhibitor. Methods. Adult patients (over 18 years) with confirmed diagnosis of IBS were examined. Biopsy specimens were taken from colon during colonoscopy for the next histological examination. One expert gastrointestinal pathologist assessed all tissue samples....

Comparison of the neurobiological effects of attribution retraining group therapy with those of selective serotonin reuptake inhibitors

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C. Wang

2013-03-01

Full Text Available The aim of this study was to compare the effectiveness of attribution retraining group therapy (ARGT with selective serotonin reuptake inhibitors (SSRIs in the treatment of major depressive disorder (MDD, generalized anxiety disorder (GAD, and obsessive-compulsive disorder (OCD. Subjects were sequentially recruited and randomized into two groups, one receiving ARGT (n = 63 and the other SSRIs (n = 66 for 8 weeks. Fifty-four ARGT outpatients with MDD (n = 19, GAD (n = 19, and OCD (n = 16 and 55 SSRI outpatients with MDD (n = 19, GAD (n = 19, and OCD (n = 17 completed the study. All subjects were assessed using the Hamilton Depression Scale and Hamilton Anxiety Scale before and after treatment. The 10-item Yale-Brown Obsessive Compulsive Scale was employed only for OCD subjects. Plasma levels of serotonin, norepinephrine, cortisol, and adrenocorticotropic hormone were also measured at baseline and 8 weeks after completion of treatment. Symptom scores were significantly reduced (P < 0.001 in both the ARGT and SSRI groups at the end of treatment. However, MDD, GAD and OCD patients in the ARGT group had significantly lower plasma cortisol concentrations compared to baseline (P < 0.05, whereas MDD and OCD patients receiving SSRIs showed significantly increased plasma levels of serotonin (P < 0.05. These findings suggest that ARGT may modulate plasma cortisol levels and affect the hypothalamus-pituitary-adrenal axis as opposed to SSRIs, which may up-regulate plasma serotonin levels via a different pathway to produce an overall improvement in the clinical condition of the patients.

Comparison of the neurobiological effects of attribution retraining group therapy with those of selective serotonin reuptake inhibitors

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C. Wang

Full Text Available The aim of this study was to compare the effectiveness of attribution retraining group therapy (ARGT with selective serotonin reuptake inhibitors (SSRIs in the treatment of major depressive disorder (MDD, generalized anxiety disorder (GAD, and obsessive-compulsive disorder (OCD. Subjects were sequentially recruited and randomized into two groups, one receiving ARGT (n = 63 and the other SSRIs (n = 66 for 8 weeks. Fifty-four ARGT outpatients with MDD (n = 19, GAD (n = 19, and OCD (n = 16 and 55 SSRI outpatients with MDD (n = 19, GAD (n = 19, and OCD (n = 17 completed the study. All subjects were assessed using the Hamilton Depression Scale and Hamilton Anxiety Scale before and after treatment. The 10-item Yale-Brown Obsessive Compulsive Scale was employed only for OCD subjects. Plasma levels of serotonin, norepinephrine, cortisol, and adrenocorticotropic hormone were also measured at baseline and 8 weeks after completion of treatment. Symptom scores were significantly reduced (P < 0.001 in both the ARGT and SSRI groups at the end of treatment. However, MDD, GAD and OCD patients in the ARGT group had significantly lower plasma cortisol concentrations compared to baseline (P < 0.05, whereas MDD and OCD patients receiving SSRIs showed significantly increased plasma levels of serotonin (P < 0.05. These findings suggest that ARGT may modulate plasma cortisol levels and affect the hypothalamus-pituitary-adrenal axis as opposed to SSRIs, which may up-regulate plasma serotonin levels via a different pathway to produce an overall improvement in the clinical condition of the patients.

Bioimpedance in monitoring of effects of selective serotonin reuptake inhibitor treatment

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Kuznecova LV

2011-06-01

Full Text Available Vasiliy Grigorievich Alexeev, Ludmila Vasilievna KuznecovaDepartment of Physiology, SP Botkin Moscow City Clinical Hospital, Moscow, RussiaBackground: Bioimpedance has been shown to be a safe technique when used in a number of biomedical applications. In this study, we used the Electro Interstitial Scan (EIS to perform bioimpedance measurements to follow up the efficacy of selective serotonin reuptake inhibitor (SSRI treatment in subjects diagnosed to have major depressive disorder.Methods: We recruited 59 subjects (38 women, 21 men aged 17–76 (mean 47 years diagnosed with major depressive disorder by psychiatric assessment at the Botkin Hospital according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV. Baseline Clinical Global Impression scores and EIS (electrical conductivity and dispersion α parameter measurements were done before starting SSRI therapy. Treatment follow-up was undertaken using EIS bioimpedance measurements and by treatment response based on the Hamilton Depression Scale and Clinical Global Impression, every 15 days for 60 days. At day 45, we classified the patients into two groups, ie, Group 1, including treatment responders, and Group 2, including nonresponders. At day 60, patients were classified into two further groups, ie, Group 3, comprising treatment responders, and Group 4, comprising nonresponders.Results: Comparing Group 1 and Group 2, electrical conductivity measurement of the pathway between the two forehead electrodes had a specificity of 72% and a sensitivity of 85.3% (P < 0.0001, with a cutoff >4.32. Comparing Group 3 and Group 4, electrical conductivity measurements in the same pathway had a specificity of 47.6% and a sensitivity of 76.3% (P < 0.16, with a cutoff >5.92. Comparing Group 1 and Group 2, the electrical dispersion α parameter of the pathway between the two disposable forehead electrodes had a specificity of 80% and a sensitivity of 85.2% (P < 0.0001 with a

Effects of selective serotonin reuptake inhibitors on thought-action fusion, metacognitions, and thought suppression in obsessive-compulsive disorder.

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Besiroglu, Lutfullah; Çetinkaya, Nuralay; Selvi, Yavuz; Atli, Abdullah

2011-01-01

We aimed to assess whether cognitive processes change over time in patients with obsessive-compulsive disorder (OCD) receiving selective serotonin reuptake inhibitors without cognitive behavioral therapy and to investigate the factors associated with probable cognitive changes. During the 16 weeks of the study, 55 patients who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for OCD received open-label treatment with sertraline (100-200 mg/d) or fluoxetine (40-80 mg/d) and were assessed using the Yale-Brown Obsessive-Compulsive Scale, Beck Depression Inventory (BDI), Thought-Action Fusion Scale (TAFS), Metacognitions Questionnaire (MCQ-30), and White Bear Suppression Inventory (WBSI). The Yale-Brown Obsessive-Compulsive Scale (P < .001), BDI (P < .001), TAFS morality (P < .005), MCQ-30 (P < .01), and WBSI (P < .005) scores at follow-up were significantly lower than baseline scores. When we excluded OCD patients with depressive disorder (n = 12), statistical significance in paired comparisons for MCQ and WBSI disappeared. Similarly, when OCD patients with religious obsessions (n = 16) were excluded, paired comparisons for MCQ and TAF morality were not statistically significant. Changes in BDI, TAFS morality, MCQ-30, and WBSI (P < .005) were significantly correlated with changes in severity of obsessions, but not that of compulsions. After controlling for the change in depression severity, significant correlations between changes in obsessive and cognitive scales did not continue to have statistical significance. The BDI changes (P < .05) significantly explained the changes in symptom severity in a linear regression model. Our findings suggest that selective serotonin reuptake inhibitors can change appraisals of obsessive intrusions via their effects on negative emotions. Copyright © 2011 Elsevier Inc. All rights reserved.

Voltammetric and Mathematical Evidence for Dual Transport Mediation of Serotonin Clearance In Vivo

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Wood, Kevin M.; Zeqja, Anisa; Nijhout, H. Frederik; Reed, Michael C.; Best, Janet; Hashemi, Parastoo

2014-01-01

The neurotransmitter serotonin underlies many of the brain’s functions. Understanding serotonin neurochemistry is important for improving treatments for neuropsychiatric disorders such as depression. Antidepressants commonly target serotonin clearance via serotonin transporters (SERTs) and have variable clinical effects. Adjunctive therapies, targeting other systems including serotonin autoreceptors, also vary clinically and carry adverse consequences. Fast scan cyclic voltammetry (FSCV) is particularly well suited for studying antidepressant effects on serotonin clearance and autoreceptors by providing real-time chemical information on serotonin kinetics in vivo. However, the complex nature of in vivo serotonin responses makes it difficult to interpret experimental data with established kinetic models. Here, we electrically stimulated the mouse medial forebrain bundle (MFB) to provoke and detect terminal serotonin in the substantia nigra reticulata (SNr). In response to MFB stimulation we found three dynamically distinct serotonin signals. To interpret these signals we developed a computational model that supports two independent serotonin reuptake mechanisms (high affinity, low efficiency reuptake mechanism and low affinity, high efficiency reuptake system) and bolsters an important inhibitory role for the serotonin autoreceptors. Our data and analysis, afforded by the powerful combination of voltammetric and theoretical methods, gives new understanding of the chemical heterogeneity of serotonin dynamics in the brain. This diverse serotonergic matrix likely contributes to clinical variability of antidepressants. PMID:24702305

Selective serotonin reuptake inhibitor antidepressant use in first trimester pregnancy and risk of congenital anomalies

DEFF Research Database (Denmark)

Wemakor, A.; Casson, K.; Garne, E.

2015-01-01

Objective / Background The Selective Serotonin Reuptake Inhibitor (SSRI) antidepressants are widely prescribed in pregnancy, but there is evidence that they may cause congenital anomalies, particularly congenital heart defects (CHD). Objective: To determine the specificity of association between...... first trimester pregnancy exposure to individual SSRI and specific congenital anomalies (CAs). Methods Population-based case-malformed control study covering 3.3 million births from 12 EUROCAT registries 1995-2009. CAs included non-syndromic live births, fetal deaths and terminations of pregnancy......% confidence intervals (CI) were calculated adjusted for registry. Results SSRI use in first trimester pregnancy was associated with CHD overall (OR 1.38, 95 % CI 1.05-1.82, n=109); and with severe CHDs (OR 1.56, 95 % CI 1.03-2.38, n=29). Specific associations between SSRI and Tetralogy of Fallot (OR 3.36, 95...

QT interval prolongation in users of selective serotonin reuptake inhibitors in an elderly surgical population

DEFF Research Database (Denmark)

van Haelst, Ingrid M M; van Klei, Wilton A; Doodeman, Hieronymus J

2014-01-01

OBJECTIVE: To investigate the association between the use of a selective serotonin reuptake inhibitor (SSRI) and the occurrence of QT interval prolongation in an elderly surgical population. METHOD: A cross-sectional study was conducted among patients (> 60 years) scheduled for outpatient...... preanesthesia evaluation in the period 2007 until 2012. The index group included elderly users of an SSRI. The reference group of nonusers of antidepressants was matched to the index group on sex and year of scheduled surgery (ratio, 1:1). The primary outcome was the occurrence of QT interval prolongation shown...... on electrocardiogram. The QT interval was corrected for heart rate (QTc interval). The secondary outcome was the duration of the QTc interval. The outcomes were adjusted for confounding by using regression techniques. RESULTS: The index and reference groups included 397 users of an SSRI and 397 nonusers, respectively...

Diminished Neural Processing of Aversive and Rewarding Stimuli During Selective Serotonin Reuptake Inhibitor Treatment

Science.gov (United States)

McCabe, Ciara; Mishor, Zevic; Cowen, Philip J.; Harmer, Catherine J.

2010-01-01

Background Selective serotonin reuptake inhibitors (SSRIs) are popular medications for anxiety and depression, but their effectiveness, particularly in patients with prominent symptoms of loss of motivation and pleasure, has been questioned. There are few studies of the effect of SSRIs on neural reward mechanisms in humans. Methods We studied 45 healthy participants who were randomly allocated to receive the SSRI citalopram, the noradrenaline reuptake inhibitor reboxetine, or placebo for 7 days in a double-blind, parallel group design. We used functional magnetic resonance imaging to measure the neural response to rewarding (sight and/or flavor of chocolate) and aversive stimuli (sight of moldy strawberries and/or an unpleasant strawberry taste) on the final day of drug treatment. Results Citalopram reduced activation to the chocolate stimuli in the ventral striatum and the ventral medial/orbitofrontal cortex. In contrast, reboxetine did not suppress ventral striatal activity and in fact increased neural responses within medial orbitofrontal cortex to reward. Citalopram also decreased neural responses to the aversive stimuli conditions in key “punishment” areas such as the lateral orbitofrontal cortex. Reboxetine produced a similar, although weaker effect. Conclusions Our findings are the first to show that treatment with SSRIs can diminish the neural processing of both rewarding and aversive stimuli. The ability of SSRIs to decrease neural responses to reward might underlie the questioned efficacy of SSRIs in depressive conditions characterized by decreased motivation and anhedonia and could also account for the experience of emotional blunting described by some patients during SSRI treatment. PMID:20034615

Nutrient-induced glucagon like peptide-1 release is modulated by serotonin.

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Ripken, Dina; van der Wielen, Nikkie; Wortelboer, Heleen M; Meijerink, Jocelijn; Witkamp, Renger F; Hendriks, Henk F J

2016-06-01

Glucagon like peptide-1 (GLP-1) and serotonin are both involved in food intake regulation. GLP-1 release is stimulated upon nutrient interaction with G-protein coupled receptors by enteroendocrine cells (EEC), whereas serotonin is released from enterochromaffin cells (ECC). The central hypothesis for the current study was that nutrient-induced GLP-1 release from EECs is modulated by serotonin through a process involving serotonin receptor interaction. This was studied by assessing the effects of serotonin reuptake inhibition by fluoxetine on nutrient-induced GLP-1, PYY and CCK release from isolated pig intestinal segments. Next, serotonin-induced GLP-1 release was studied in enteroendocrine STC-1 cells, where effects of serotonin receptor inhibition were studied using specific and non-specific antagonists. Casein (1% w/v), safflower oil (3.35% w/v), sucrose (50mM) and rebaudioside A (12.5mM) stimulated GLP-1 release from intestinal segments, whereas casein only stimulated PYY and CCK release. Combining nutrients with fluoxetine further increased nutrient-induced GLP-1, PYY and CCK release. Serotonin release from intestinal tissue segments was stimulated by casein and safflower oil while sucrose and rebaudioside A had no effect. The combination with fluoxetine (0.155μM) further enhanced casein and safflower oil induced-serotonin release. Exposure of ileal tissue segments to serotonin (30μM) stimulated GLP-1 release whereas it did not induce PYY and CCK release. Serotonin (30 and 100μM) also stimulated GLP-1 release from STC-1 cells, which was inhibited by the non-specific 5HT receptor antagonist asenapine (1 and 10μM). These data suggest that nutrient-induced GLP-1 release is modulated by serotonin through a receptor mediated process. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Selective Serotonin Reuptake Inhibitors in Human Pregnancy: To Treat or Not to Treat?

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Orna Diav-Citrin

2012-01-01

Full Text Available Selective serotonin reuptake inhibitors (SSRIs are increasingly prescribed during pregnancy. The purpose of the present paper is to summarize and evaluate the current evidence for the risk/benefit analysis of SSRI use in human pregnancy. The literature has been inconsistent. Although most studies have not shown an increase in the overall risk of major malformations, several studies have suggested that SSRIs may be associated with a small increased risk for cardiovascular malformations. Others have noted associations between SSRIs and specific types of rare major malformations. In some studies, there appears to be a small increased risk for miscarriages, which may be associated with the underlying maternal condition. Neonatal effects have been described in up to 30% of neonates exposed to SSRIs late in pregnancy. Persistent pulmonary hypertension of the newborn has also been described with an absolute risk of <1%. The risk associated with treatment discontinuation, for example, higher frequency of relapse and increased risk of preterm delivery, should also be considered. The overall benefit of treatment seems to outweigh the potential risks.

Acute serotonin depletion releases motivated inhibition of response vigour.

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den Ouden, Hanneke E M; Swart, Jennifer C; Schmidt, Kristin; Fekkes, Durk; Geurts, Dirk E M; Cools, Roshan

2015-04-01

The neurotransmitter serotonin has long been implicated in the motivational control of behaviour. Recent theories propose that the role of serotonin can be understood in terms of an interaction between a motivational and a behavioural activation axis. Experimental support for these ideas, however, has been mixed. In the current study, we aimed to investigate the role of serotonin (5HT) in behavioural vigour as a function of incentive motivation. We employed dietary acute tryptophan depletion (ATD) to lower the 5HT precursor tryptophan during the performance of a speeded visual discrimination task. Feedback valence and feedback probability were manipulated independently and cued prior to target onset. On feedback trials, fast correct responses led to either reward or avoidance of punishment, while slow or incorrect responses led to reward omission or punishment. We show that behavioural responding is inhibited under high incentive motivation (i.e. high-feedback probability) at baseline 5HT levels and that lowering these leads to behavioural disinhibition, while leaving accuracy unaffected. Surprisingly, there were no differential effects of motivational valence, with 5HT depletion releasing behavioural inhibition under both appetitive and aversive motivation. Our findings extend current theories on the role of 5HT in behavioural inhibition by showing that reductions in serotonin lead to increased behavioural vigour only if there is a motivational drive to inhibit behaviour at baseline.

Serotonin transporter gene promoter polymorphisms modify the association between paroxetine serotonin transporter occupancy and clinical response in major depressive disorder

NARCIS (Netherlands)

Ruhé, Henricus G.; Ooteman, Wendy; Booij, Jan; Michel, Martin C.; Moeton, Martina; Baas, Frank; Schene, Aart H.

2009-01-01

BACKGROUND: In major depressive disorder, selective serotonin reuptake inhibitors target the serotonin transporter (SERT). Their response rates (30-50%) are modified by SERT promotor polymorphisms (5-HTTLPR). OBJECTIVES: To quantify the relationship between SERT occupancy and response, and whether

Steroidogenic disruptive effects of the serotonin-noradrenaline reuptake inhibitors duloxetine, venlafaxine and tramadol in the H295R cell assay and in a recombinant CYP17 assay

DEFF Research Database (Denmark)

Islin, Julie; Munkboel, Cecilie Hurup; Styrishave, Bjarne

2018-01-01

The aim of this study was to determine the steroidogenic endocrine disrupting effect of the three most widely used serotonin-noradrenaline reuptake inhibitors duloxetine, venlafaxine and tramadol, using two in vitro models, the H295R assay and a recombinant CYP17 enzyme assay. Steroid hormones were...... quantified using LC-MS/MS. Duloxetine showed endocrine disrupting effects at 5-20μM with CYP17 being the main target. Venlafaxine also affected the steroidogenesis, mainly by affecting the CYP17 lyase reaction, although at much higher concentrations i.e. 100μM. Tramadol only exerted minor effects...... on the steroidogenesis with the lowest observed effect at 314μM. Based on the H295R results, the inhibition of CYP17 by duloxetine and venlafaxine was investigated in a recombinant CYP17 assay with the use of the 4 major CYP17 substrates pregnenolone, progesterone, 17α-hydroxypregnenolone and 17α...

Reviewing the serotonin reuptake inhibitors (SSRIs) footprint in the aquatic biota: Uptake, bioaccumulation and ecotoxicology

International Nuclear Information System (INIS)

a Comba, 3000-548 Coimbra (Portugal))" data-affiliation=" (REQUIMTE, Group of Bromatology, Pharmacognosy and Analytical Sciences, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra (Portugal))" >Silva, Liliana J.G.; a Comba, 3000-548 Coimbra (Portugal))" data-affiliation=" (REQUIMTE, Group of Bromatology, Pharmacognosy and Analytical Sciences, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra (Portugal))" >Pereira, André a Comba, 3000-548 Coimbra (Portugal))" data-affiliation=" (REQUIMTE, Group of Bromatology, Pharmacognosy and Analytical Sciences, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra (Portugal))" >M.P.T.; Meisel, Leonor M.; a Comba, 3000-548 Coimbra (Portugal))" data-affiliation=" (REQUIMTE, Group of Bromatology, Pharmacognosy and Analytical Sciences, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra (Portugal))" >Lino, Celeste M.; a Comba, 3000-548 Coimbra (Portugal))" data-affiliation=" (REQUIMTE, Group of Bromatology, Pharmacognosy and Analytical Sciences, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Sta Comba, 3000-548 Coimbra (Portugal))" >Pena, Angelina

2015-01-01

Selective serotonin re-uptake inhibitors (SSRIs) antidepressants are amongst the most prescribed pharmaceutical active substances throughout the world. Their presence, already described in different environmental compartments such as wastewaters, surface, ground and drinking waters, and sediments, and their remarkable effects on non-target organisms justify the growing concern about these emerging environmental pollutants. A comprehensive review of the literature data with focus on their footprint in the aquatic biota, namely their uptake, bioaccumulation and both acute and chronic ecotoxicology is presented. Long-term multigenerational exposure studies, at environmental relevant concentrations and in mixtures of related compounds, such as oestrogenic endocrine disruptors, continue to be sparse and are imperative to better know their environmental impact. - Highlights: • Current knowledge of uptake and bioaccumulation of SSRIs. • Ecotoxicology and effects of SSRIs in the aquatic biota. • Identification of existing knowledge gaps. - A comprehensive review focussing SSRIs antidepressants footprint in the aquatic biota, namely their uptake, bioaccumulation, and both acute and chronic ecotoxicology is presented

Genetic predictors of response to antidepressants in the GENDEP project

DEFF Research Database (Denmark)

Uher, Rudolf; Huezo-Diaz, Patricia; Perroud, Nader

2009-01-01

-reuptake-inhibiting and norepinephrine-reuptake-inhibiting antidepressants. A total of 116 single nucleotide polymorphisms in 10 candidate genes were genotyped in 760 adult patients with moderate-to-severe depression, treated with escitalopram (a serotonin reuptake inhibitor) or nortriptyline (a norepinephrine reuptake inhibitor......) for 12 weeks in an open-label part-randomized multicenter study. The effect of genetic variants on change in depressive symptoms was evaluated using mixed linear models. Several variants in a serotonin receptor gene (HTR2A) predicted response to escitalopram with one marker (rs9316233) explaining 1...... to the serotonin-reuptake-inhibiting escitalopram, genes encoding proteins in norepinephrine signaling influencing response to the norepinephrine-reuptake-inhibiting nortriptyline and a common pathway gene influencing response to both antidepressants. The single marker associations explained only a small...

Serotonin inhibits low-threshold spike interneurons in the striatum

Science.gov (United States)

Cains, Sarah; Blomeley, Craig P; Bracci, Enrico

2012-01-01

Low-threshold spike interneurons (LTSIs) are important elements of the striatal architecture and the only known source of nitric oxide in this nucleus, but their rarity has so far prevented systematic studies. Here, we used transgenic mice in which green fluorescent protein is expressed under control of the neuropeptide Y (NPY) promoter and striatal NPY-expressing LTSIs can be easily identified, to investigate the effects of serotonin on these neurons. In sharp contrast with its excitatory action on other striatal interneurons, serotonin (30 μm) strongly inhibited LTSIs, reducing or abolishing their spontaneous firing activity and causing membrane hyperpolarisations. These hyperpolarisations persisted in the presence of tetrodotoxin, were mimicked by 5-HT2C receptor agonists and reversed by 5-HT2C antagonists. Voltage-clamp slow-ramp experiments showed that serotonin caused a strong increase in an outward current activated by depolarisations that was blocked by the specific M current blocker XE 991. In current-clamp experiments, XE 991 per se caused membrane depolarisations in LTSIs and subsequent application of serotonin (in the presence of XE 991) failed to affect these neurons. We concluded that serotonin strongly inhibits striatal LTSIs acting through postsynaptic 5-HT2C receptors and increasing an M type current. PMID:22495583

Interaction of antidepressants with the serotonin and norepinephrine transporters

DEFF Research Database (Denmark)

Sørensen, Lena; Andersen, Jacob; Thomsen, Mette

2012-01-01

The serotonin transporter (SERT) and the norepinephrine transporter (NET) are sodium-dependent neurotransmitter transporters responsible for reuptake of released serotonin and norepinephrine, respectively, into nerve terminals in the brain. A wide range of inhibitors of SERT and NET are used...

Triptans, serotonin agonists, and serotonin syndrome (serotonin toxicity): a review.

Science.gov (United States)

Gillman, P Ken

2010-02-01

The US Food and Drug Administration (FDA) have suggested that fatal serotonin syndrome (SS) is possible with selective serotonin reuptake inhibitors (SSRIs) and triptans: this warning affects millions of patients as these drugs are frequently given simultaneously. SS is a complex topic about which there is much misinformation. The misconception that 5-HT1A receptors can cause serious SS is still widely perpetuated, despite quality evidence that it is activation of the 5-HT2A receptor that is required for serious SS. This review considers SS involving serotonin agonists: ergotamine, lysergic acid diethylamide, bromocriptine, and buspirone, as well as triptans, and reviews the experimental foundation underpinning the latest understanding of SS. It is concluded that there is neither significant clinical evidence, nor theoretical reason, to entertain speculation about serious SS from triptans and SSRIs. The misunderstandings about SS exhibited by the FDA, and shared by the UK Medicines and Healthcare products Regulatory Agency (in relation to methylene blue), are an important issue with wide ramifications.

Increased risk of severe congenital heart defects in offspring exposed to selective serotonin-reuptake inhibitors in early pregnancy

DEFF Research Database (Denmark)

Knudsen, Tanja Majbrit; Hansen, Anne Vinkel; Garne, Ester

2014-01-01

BACKGROUND: Previous studies suggest a possible association between maternal use of selective serotonin-reuptake inhibitors (SSRIs) during early pregnancy and congenital heart defects (CHD). The purpose of this study was to verify this association by using validated data from the Danish EUROCAT...... terminated due to congenital anomalies. The study population consisted of all registered pregnancies (n = 72,280) in Funen, Denmark in the period 1995-2008. SSRI-use was assessed using The Danish National Prescription Registry, information on marital status, maternal educational level, income, and country...... of origin from Statistics Denmark was used as indicators of socioeconomic situation, and the CHD were studied in subgroups defined by EUROCAT. Logistic Regression was used to investigate the association between redeemed prescriptions for SSRIs and CHD. RESULTS: The risk of severe CHD in the offspring...

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

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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.

Rapid screening of selective serotonin re-uptake inhibitors in urine samples using solid-phase microextraction gas chromatography-mass spectrometry.

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Salgado-Petinal, Carmen; Lamas, J Pablo; Garcia-Jares, Carmen; Llompart, Maria; Cela, Rafael

2005-07-01

In this paper a solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) method is proposed for a rapid analysis of some frequently prescribed selective serotonin re-uptake inhibitors (SSRI)-venlafaxine, fluvoxamine, mirtazapine, fluoxetine, citalopram, and sertraline-in urine samples. The SPME-based method enables simultaneous determination of the target SSRI after simple in-situ derivatization of some of the target compounds. Calibration curves in water and in urine were validated and statistically compared. This revealed the absence of matrix effect and, in consequence, the possibility of quantifying SSRI in urine samples by external water calibration. Intra-day and inter-day precision was satisfactory for all the target compounds (relative standard deviation, RSD, detection limits achieved were detected and tentatively identified.

Contribution of Helicobacter pylori infection to the risk of peptic ulcer bleeding in patients on nonsteroidal anti-inflammatory drugs, antiplatelet agents, anticoagulants, corticosteroids and selective serotonin reuptake inhibitors.

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Venerito, M; Schneider, C; Costanzo, R; Breja, R; Röhl, F-W; Malfertheiner, P

2018-06-01

Nonsteroidal anti-inflammatory drugs, low-dose aspirin, non-aspirin antiplatelet agents, anticoagulants, selective serotonin reuptake inhibitors and corticosteroids increase the risk of gastroduodenal bleeding. To determine in a retrospective cohort study the contribution of Helicobacter pylori infection to the risk of peptic ulcer bleeding in patients taking these drugs. Among patients with peptic ulcer disease diagnosed by endoscopy from 01/2004 to 12/2014 (N = 1719, 60% males, age 65.8 ± 14.5), 56.9% had peptic ulcer bleeding (cases) and 43.1% uncomplicated peptic ulcer disease (controls). Demographics, intake of nonsteroidal anti-inflammatory drugs, aspirin, non-aspirin antiplatelet agents, anticoagulants, selective serotonin reuptake inhibitors, proton pump inhibitors and corticosteroids were documented. H. pylori status was determined by histology, rapid urease test or serology. Adjusted odds ratios (OR) were estimated by logistic regression analysis. Helicobacter pylori infection increased the risk of peptic ulcer bleeding in nonsteroidal anti-inflammatory drug and aspirin users (OR = 2.91, 95% CI = 1.71-4.98 and OR = 2.23, 95% CI = 1.52-3.28, respectively), but not in patients on anticoagulants, selective serotonin reuptake inhibitor or corticosteroid therapy. H. pylori-positive status substantially increased the risk of peptic ulcer bleeding in patients on non-aspirin antiplatelet agents (OR = 4.37, 95% CI = 1.28-14.99), concomitant aspirin/nonsteroidal anti-inflammatory drug intake (OR = 5.85, 95% CI = 1.68-20.36) and combined antiplatelet therapy (OR = 8.43, 95% CI = 1.09-65.17). After further adjustment for proton pump inhibitor intake, H. pylori infection was still a risk factor for peptic ulcer bleeding in nonsteroidal anti-inflammatory drug and aspirin users. Helicobacter pylori infection increases the risk of peptic ulcer bleeding in peptic ulcer disease patients on nonsteroidal anti-inflammatory drugs, aspirin and non

Inhibition of serotonin transport by (+)McN5652 is noncompetitive

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Hummerich, Rene [Biochemical Laboratory, Central Institute of Mental Health, 68159 Mannheim (Germany); Schulze, Oliver [Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, D-20246 Hamburg (Germany); Raedler, Thomas [Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, D-20246 Hamburg (Germany); Mikecz, Pal [Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, D-20246 Hamburg (Germany); Reimold, Matthias [Department of Nuclear Medicine, University Hospital Tuebingen, D-72076 Tuebingen (Germany); Brenner, Winfried [Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, D-20246 Hamburg (Germany); Clausen, Malte [Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, D-20246 Hamburg (Germany); Schloss, Patrick [Biochemical Laboratory, Central Institute of Mental Health, 68159 Mannheim (Germany); Buchert, Ralph [Department of Nuclear Medicine, University Medical Center Hamburg-Eppendorf, D-20246 Hamburg (Germany)]. E-mail: buchert@uke.uni-hamburg.de

2006-04-15

Introduction: Imaging of the serotonergic innervation of the brain using positron emission tomography (PET) with the serotonin transporter (SERT) ligand [{sup 11C}] (+)McN5652 might be affected by serotonin in the synaptic cleft if there is relevant interaction between [{sup 11}C] (+)McN5652 and serotonin at the SERT. The aim of the present study therefore was to pharmacologically characterize the interaction of [{sup 11}C] (+)McN5652 and serotonin at the SERT. Methods: In vitro saturation analyses of [{sup 3}H]serotonin uptake into HEK293 cells stably expressing the human SERT were performed in the absence and presence of unlabelled (+)McN5652. Data were evaluated assuming Michaelis-Menten kinetics. Results: Unlabelled (+)McN5652 significantly reduced the maximal rate of serotonin transport V {sub max} of SERT without affecting the Michaelis-Menten constant K {sub M}. Conclusions: This finding indicates that (+)McN5652 inhibits serotonin transport through the SERT in a noncompetitive manner. This might suggest that [{sup 11}C] (+)McN5652 PET is not significantly affected by endogenous serotonin.

Inhibition of serotonin transport by (+)McN5652 is noncompetitive

International Nuclear Information System (INIS)

Hummerich, Rene; Schulze, Oliver; Raedler, Thomas; Mikecz, Pal; Reimold, Matthias; Brenner, Winfried; Clausen, Malte; Schloss, Patrick; Buchert, Ralph

2006-01-01

Introduction: Imaging of the serotonergic innervation of the brain using positron emission tomography (PET) with the serotonin transporter (SERT) ligand [ 11C ] (+)McN5652 might be affected by serotonin in the synaptic cleft if there is relevant interaction between [ 11 C] (+)McN5652 and serotonin at the SERT. The aim of the present study therefore was to pharmacologically characterize the interaction of [ 11 C] (+)McN5652 and serotonin at the SERT. Methods: In vitro saturation analyses of [ 3 H]serotonin uptake into HEK293 cells stably expressing the human SERT were performed in the absence and presence of unlabelled (+)McN5652. Data were evaluated assuming Michaelis-Menten kinetics. Results: Unlabelled (+)McN5652 significantly reduced the maximal rate of serotonin transport V max of SERT without affecting the Michaelis-Menten constant K M . Conclusions: This finding indicates that (+)McN5652 inhibits serotonin transport through the SERT in a noncompetitive manner. This might suggest that [ 11 C] (+)McN5652 PET is not significantly affected by endogenous serotonin

A dualistic conformational response to substrate binding in the human serotonin transporter reveals a high affinity state for serotonin

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Bjerregaard, Henriette; Severinsen, Kasper; Said, Saida

2015-01-01

Serotonergic neurotransmission is modulated by the membrane-embedded serotonin transporter (SERT). SERT mediates the reuptake of serotonin into the presynaptic neurons. Conformational changes in SERT occur upon binding of ions and substrate and are crucial for translocation of serotonin across...... the membrane. Our understanding of these conformational changes is mainly based on crystal structures of a bacterial homolog in various conformations, derived homology models of eukaryotic neurotransmitter transporters, and substituted cysteine accessibility method of SERT. However, the dynamic changes...

Selective serotonin reuptake inhibitors and gastrointestinal bleeding: a case-control study.

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Alfonso Carvajal

Full Text Available BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs have been associated with upper gastrointestinal (GI bleeding. Given their worldwide use, even small risks account for a large number of cases. This study has been conducted with carefully collected information to further investigate the relationship between SSRIs and upper GI bleeding. METHODS: We conducted a case-control study in hospitals in Spain and in Italy. Cases were patients aged ≥18 years with a primary diagnosis of acute upper GI bleeding diagnosed by endoscopy; three controls were matched by sex, age, date of admission (within 3 months and hospital among patients who were admitted for elective surgery for non-painful disorders. Exposures to SSRIs, other antidepressants and other drugs were defined as any use of these drugs in the 7 days before the day on which upper gastrointestinal bleeding started (index day. RESULTS: 581 cases of upper GI bleeding and 1358 controls were considered eligible for the study; no differences in age or sex distribution were observed between cases and controls after matching. Overall, 4.0% of the cases and 3.3% of controls used an SSRI antidepressant in the week before the index day. No significant risk of upper GI bleeding was encountered for SSRI antidepressants (adjusted odds ratio, 1.06, 95% CI, 0.57-1.96 or for whichever other grouping of antidepressants. CONCLUSIONS: The results of this case-control study showed no significant increase in upper GI bleeding with SSRIs and provide good evidence that the magnitude of any increase in risk is not greater than 2.

Social inequalities in suicide: the role of selective serotonin reuptake inhibitors.

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Clouston, Sean A P; Rubin, Marcie S; Colen, Cynthia G; Link, Bruce G

2014-10-01

We aimed to examine the relationship between socioeconomic status (SES) and suicide associated with the introduction and diffusion of selective serotonin reuptake inhibitors (SSRIs). Negative binomial regression was used to estimate county-level suicide rates among persons aged 25 years or older using death certificate data collated by the National Center for Health Statistics from 1968 to 2009; SES was measured using the decennial US Census. The National Health and Nutrition Examination Survey and the Medical Expenditure Panel Survey were used to measure SSRI use. Once SSRIs became available in 1988, a 1% increase in SSRI usage was associated with a 0.5% lower suicide rate. Prior to the introduction of SSRIs, SES was not related to suicide. However, with each 1% increase in SSRI use, a 1-standard deviation (SD) higher SES was associated with a 0.6% lower suicide rate. In 2009, persons living in counties with SES 1 SD above the national average were 13.6% less likely to commit suicide than those living in counties with SES 1 SD below the national average--a difference of 1.9/100,000 adults aged ≥25 years. Higher SSRI use was associated with lower suicide rates among US residents aged ≥25 years; however, SES inequalities modified the association between SSRI use and suicide. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Mechanistic Basis for Noncompetitive Ibogaine Inhibition of Serotonin and Dopamine Transporters*

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Bulling, Simon; Schicker, Klaus; Zhang, Yuan-Wei; Steinkellner, Thomas; Stockner, Thomas; Gruber, Christian W.; Boehm, Stefan; Freissmuth, Michael; Rudnick, Gary; Sitte, Harald H.; Sandtner, Walter

2012-01-01

Ibogaine, a hallucinogenic alkaloid proposed as a treatment for opiate withdrawal, has been shown to inhibit serotonin transporter (SERT) noncompetitively, in contrast to all other known inhibitors, which are competitive with substrate. Ibogaine binding to SERT increases accessibility in the permeation pathway connecting the substrate-binding site with the cytoplasm. Because of the structural similarity between ibogaine and serotonin, it had been suggested that ibogaine binds to the substrate site of SERT. The results presented here show that ibogaine binds to a distinct site, accessible from the cell exterior, to inhibit both serotonin transport and serotonin-induced ionic currents. Ibogaine noncompetitively inhibited transport by both SERT and the homologous dopamine transporter (DAT). Ibogaine blocked substrate-induced currents also in DAT and increased accessibility of the DAT cytoplasmic permeation pathway. When present on the cell exterior, ibogaine inhibited SERT substrate-induced currents, but not when it was introduced into the cytoplasm through the patch electrode. Similar to noncompetitive transport inhibition, the current block was not reversed by increasing substrate concentration. The kinetics of inhibitor binding and dissociation, as determined by their effect on SERT currents, indicated that ibogaine does not inhibit by forming a long-lived complex with SERT, but rather binds directly to the transporter in an inward-open conformation. A kinetic model for transport describing the noncompetitive action of ibogaine and the competitive action of cocaine accounts well for the results of the present study. PMID:22451652

The mechanistic basis for noncompetitive ibogaine inhibition of serotonin and dopamine transporters.

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Bulling, Simon; Schicker, Klaus; Zhang, Yuan-Wei; Steinkellner, Thomas; Stockner, Thomas; Gruber, Christian W; Boehm, Stefan; Freissmuth, Michael; Rudnick, Gary; Sitte, Harald H; Sandtner, Walter

2012-05-25

Ibogaine, a hallucinogenic alkaloid proposed as a treatment for opiate withdrawal, has been shown to inhibit serotonin transporter (SERT) noncompetitively, in contrast to all other known inhibitors, which are competitive with substrate. Ibogaine binding to SERT increases accessibility in the permeation pathway connecting the substrate-binding site with the cytoplasm. Because of the structural similarity between ibogaine and serotonin, it had been suggested that ibogaine binds to the substrate site of SERT. The results presented here show that ibogaine binds to a distinct site, accessible from the cell exterior, to inhibit both serotonin transport and serotonin-induced ionic currents. Ibogaine noncompetitively inhibited transport by both SERT and the homologous dopamine transporter (DAT). Ibogaine blocked substrate-induced currents also in DAT and increased accessibility of the DAT cytoplasmic permeation pathway. When present on the cell exterior, ibogaine inhibited SERT substrate-induced currents, but not when it was introduced into the cytoplasm through the patch electrode. Similar to noncompetitive transport inhibition, the current block was not reversed by increasing substrate concentration. The kinetics of inhibitor binding and dissociation, as determined by their effect on SERT currents, indicated that ibogaine does not inhibit by forming a long-lived complex with SERT, but rather binds directly to the transporter in an inward-open conformation. A kinetic model for transport describing the noncompetitive action of ibogaine and the competitive action of cocaine accounts well for the results of the present study.

Action of selective serotonin reuptake inhibitor on aggressive behavior in adult rat submitted to the neonatal malnutrition

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Medeiros Jairza Maria Barreto

2001-01-01

Full Text Available The effect of the malnutrition during suckling on the aggressiveness was investigated in adult rats treated or not with citalopram, a selective serotonin reuptake inhibitor (SSRI. The animals were divided into two groups according to the diet used: nourished group-- the rats received the control diet with 23% protein during the life; and malnourished group-- the rats had its mothers submitted to diet with 7.8% protein during suckling. At 120 days of age, each group was sub-divided according to the treatment: acute -- consisting a single i.p. injection of saline solution or 20-mg/Kg citalopram; chronic -- consisting the single injections (1 per day during 14 days of saline or 20 mg/Kg citalopram. The acute or chronic treatment with SSRI reduces aggressive response in nourished rats, but not in malnourished ones. Thus, the malnutrition during the critical period of brain development seems to induce durable alterations in the function of the serotoninergic neurotransmission

Serotonin enhances the impact of health information on food choice.

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Vlaev, Ivo; Crockett, Molly J; Clark, Luke; Müller, Ulrich; Robbins, Trevor W

2017-06-01

Serotonin has been implicated in promoting self-control, regulation of hunger and physiological homeostasis, and regulation of caloric intake. However, it remains unclear whether the effects of serotonin on caloric intake reflect purely homeostatic mechanisms, or whether serotonin also modulates cognitive processes involved in dietary decision making. We investigated the effects of an acute dose of the serotonin reuptake inhibitor citalopram on choices between food items that differed along taste and health attributes, compared with placebo and the noradrenaline reuptake inhibitor atomoxetine. Twenty-seven participants attended three sessions and received single doses of atomoxetine, citalopram, and placebo in a double-blind randomised cross-over design. Relative to placebo, citalopram increased choices of more healthy foods over less healthy foods. Citalopram also increased the emphasis on health considerations in decisions. Atomoxetine did not affect decision making relative to placebo. The results support the hypothesis that serotonin may influence food choice by enhancing a focus on long-term goals. The findings are relevant for understanding decisions about food consumption and also for treating health conditions such as eating disorders and obesity.

Chronic fluoxetine inhibits sexual behavior in the male rat: reversal with oxytocin.

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Cantor, J M; Binik, Y M; Pfaus, J G

1999-06-01

Selective serotonin reuptake inhibitors, used widely in the treatment of depression, progressively inhibit sexual orgasm in many patients and induce a transient inhibition of sexual desire. We attempted to model the effects of these drugs in sexually experienced male rats during tests of copulation in bilevel chambers. These chambers allow the study of both appetitive and consummatory sexual responses of male rats. Males were treated daily with fluoxetine hydrochloride (0, 1, 5, or 10 mg/kg) and tested for sexual behavior with receptive females at 4-day intervals. Rats were treated with oxytocin (200 ng/kg) or saline after ejaculations had decreased. Fluoxetine decreased ejaculatory responses of male rats in a dose- and time-dependent fashion, but left the copulatory efficiency of the males intact. In contrast, conditioned level changing, a measure of appetitive sexual excitement, was inhibited following acute and chronic treatment with 10 mg/kg, although tolerance may have developed to the effect of 5 mg/kg. Subsequent administration of oxytocin restored the ejaculatory response but not the measure of sexual excitement to baseline levels. The reversal by oxytocin of the fluoxetine-induced deficit in ejaculations is consistent with the hypothesis that serotonin suppresses ejaculatory mechanisms by interrupting the action of oxytocin, which normally accompanies sexual behavior. Co-administration of oxytocin may help to alleviate the predominant sexual side effect of serotonin reuptake blockers.

Prenatal serotonin reuptake inhibitor (SRI antidepressant exposure and serotonin transporter promoter genotype (SLC6A4 influence executive functions at 6 years of age

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Whitney eWeikum

2013-10-01

Full Text Available Prenatal exposure to serotonin reuptake inhibitor (SRI antidepressants and maternal depression may affect prefrontal cognitive skills (executive functions; EFs including self-control, working memory and cognitive flexibility. We examined long-term effects of prenatal SRI exposure on EFs to determine whether effects are moderated by maternal mood and/or genetic variations in SLC6A4 (a gene that codes for the serotonin transporter [5-HTT] central to the regulation of synaptic serotonin levels and behavior. Children who were exposed to SRIs prenatally (SRI-exposed N=26 and non-exposed (N=38 were studied at age 6 years (M=6.3 SD=0.5 using the Hearts & Flowers task (H&F to assess EFs. Maternal mood was measured during pregnancy (3rd trimester and when the child was age 6 years (Hamilton Depression Scale. Parent reports of child behavior were also obtained (MacArthur Health & Behavior Questionnaire. Parents of prenatally SRI-exposed children reported fewer child externalizing and inattentive (ADHD behaviors. Generalized estimate equation modeling showed a significant 3-way interaction between prenatal SRI exposure, SLC6A4 variant, and maternal mood at the 6-year time-point on H&F accuracy. For prenatally SRI-exposed children, regardless of maternal mood, the H&F accuracy of children with reduced 5HTT expression (a short [S] allele remained stable. Even with increasing maternal depressive symptoms (though all below clinical threshold, EFs of children with at least one short allele were comparable to children with the same genotype whose mothers reported few if any depressive symptoms – in this sense they showed resilience. Children with two long (L alleles were more sensitive to context. When their mothers had few depressive symptoms, LL children showed extremely good EF performance – better than any other group. When their mothers reported more depressive symptoms, LL children’s EF performance was worse than that of any other group.

Dopamine and serotonin: influences on male sexual behavior.

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Hull, Elaine M; Muschamp, John W; Sato, Satoru

2004-11-15

Steroid hormones regulate sexual behavior primarily by slow, genomically mediated effects. These effects are realized, in part, by enhancing the processing of relevant sensory stimuli, altering the synthesis, release, and/or receptors for neurotransmitters in integrative areas, and increasing the responsiveness of appropriate motor outputs. Dopamine has facilitative effects on sexual motivation, copulatory proficiency, and genital reflexes. Dopamine in the nigrostriatal tract influences motor activity; in the mesolimbic tract it activates numerous motivated behaviors, including copulation; in the medial preoptic area (MPOA) it controls genital reflexes, copulatory patterns, and specifically sexual motivation. Testosterone increases nitric oxide synthase in the MPOA; nitric oxide increases basal and female-stimulated dopamine release, which in turn facilitates copulation and genital reflexes. Serotonin (5-HT) is primarily inhibitory, although stimulation of 5-HT(2C) receptors increases erections and inhibits ejaculation, whereas stimulation of 5-HT(1A) receptors has the opposite effects: facilitation of ejaculation and, in some circumstances, inhibition of erection. 5-HT is released in the anterior lateral hypothalamus at the time of ejaculation. Microinjections of selective serotonin reuptake inhibitors there delay the onset of copulation and delay ejaculation after copulation begins. One means for this inhibition is a decrease in dopamine release in the mesolimbic tract.

Approach to novel functional foods for stress control 4. Regulation of serotonin transporter by food factors.

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Ito, Mikiko; Haito, Sakiko; Furumoto, Mari; Kawai, Yoshichika; Terao, Junji; Miyamoto, Ken-ichi

2005-11-01

Serotonin transporters (SERTs) are pre-synaptic proteins specialized for the clearance of serotonin following vesicular release at central nervous system (CNS) and enteric nervous system synapses. SERTs are high affinity targets in vivo for antidepressants such as serotonin selective reuptake inhibitors (SSRIs). These include 'medical' psychopharmacological agents such as analgesics and antihistamines, a plant extract called St John's Wort (Hypericum). Osteoclasts are the primary cells responsible for bone resorption. They arise by the differentiation of osteoclast precursors of the monocyte/macrophage lineage. The expression of SERTs was increased in RANKL-induced osteoclast-like cells. Using RANKL stimulation of RAW264.7 cells as a model system for osteoclast differentiation, we studied the direct effects of food factor on serotonin uptake. The SSRIs (fluoxetine and fluvoxamine) inhibited markedly (approximately 95%) in serotonin transport in differentiated osteoclast cells. The major components of St. John's Wort, hyperforin and hypericine were significantly decreased in serotonin transport activity. Thus, a new in vitro model using RANKL-induced osteoclast-like cells may be useful to analyze the regulation of SERT by food factors and SSRIs.

Impact of prestroke selective serotonin reuptake inhibitor treatment on stroke severity and mortality.

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Mortensen, Janne Kaergaard; Larsson, Heidi; Johnsen, Søren Paaske; Andersen, Grethe

2014-07-01

Selective serotonin reuptake inhibitors (SSRIs) have been associated with an increased risk of bleeding but also a possible neuroprotective effect in stroke. We aimed to examine the implications of prestroke SSRI use in hemorrhagic and ischemic stroke. We conducted a registry-based propensity score-matched follow-up study among first-ever patients with hemorrhage and ischemic stroke in Denmark (2003-2012). Multiple conditional logistic regression was used to compute adjusted odds ratios of severe stroke and death within 30 days. Among 1252 hemorrhagic strokes (626 prestroke SSRI users and 626 propensity score-matched nonusers), prestroke SSRI use was associated with an increased risk of the strokes being severe (adjusted propensity score-matched odds ratios, 1.41; confidence interval, 1.08-1.84) and an increased risk of death within 30 days (adjusted propensity score-matched odds ratios, 1.60; confidence interval, 1.17-2.18). Among 8956 patients with ischemic stroke (4478 prestroke SSRI users and 4478 propensity score-matched nonusers), prestroke SSRI use was not associated with the risk of severe stroke or death within 30 days. Prestroke SSRI use is associated with increased stroke severity and mortality in patients with hemorrhagic stroke. Although prestroke depression in itself may increase stroke severity and mortality, this was not found in SSRI users with ischemic stroke. © 2014 American Heart Association, Inc.

Possibility of Predicting Serotonin Transporter Occupancy From the In Vitro Inhibition Constant for Serotonin Transporter, the Clinically Relevant Plasma Concentration of Unbound Drugs, and Their Profiles for Substrates of Transporters.

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Yahata, Masahiro; Chiba, Koji; Watanabe, Takao; Sugiyama, Yuichi

2017-09-01

Accurate prediction of target occupancy facilitates central nervous system drug development. In this review, we discuss the predictability of serotonin transporter (SERT) occupancy in human brain estimated from in vitro K i values for human SERT and plasma concentrations of unbound drug (C u,plasma ), as well as the impact of drug transporters in the blood-brain barrier. First, the geometric means of in vitro K i values were compared with the means of in vivo K i values (K i,u,plasma ) which were calculated as C u,plasma values at 50% occupancy of SERT obtained from previous clinical positron emission tomography/single photon emission computed tomography imaging studies for 6 selective serotonin transporter reuptake inhibitors and 3 serotonin norepinephrine reuptake inhibitors. The in vitro K i values for 7 drugs were comparable to their in vivo K i,u,plasma values within 3-fold difference. SERT occupancy was overestimated for 5 drugs (P-glycoprotein substrates) and underestimated for 2 drugs (presumably uptake transporter substrates, although no evidence exists as yet). In conclusion, prediction of human SERT occupancy from in vitro K i values and C u,plasma was successful for drugs that are not transporter substrates and will become possible in future even for transporter substrates, once the transporter activities will be accurately estimated from in vitro experiments. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

The market dynamics of selective serotonin re-uptake inhibitors: a ...

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re-uptake inhibitors: a private sector study in South Africa. Afri Health ... the public and private sectors to reduce medicine costs, and increase ... Fig 1: Comparison between the market volume of generics vs. originators for the period June 2009 ...

Chronic Pain Treatment: The Influence of Tricyclic Antidepressants on Serotonin Release and Uptake in Mast Cells

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Ilonka Ferjan

2013-01-01

Full Text Available The involvement of serotonin (5-HT in chronic pain mechanisms is established. 5-HT inhibits central painful stimuli, but recent data suggests that 5-HT could also enhance pain stimulus from the periphery, where mast cells play an important role. We aimed in our study to clarify the influence of selected tricyclic antidepressants (TCAs on mast cell function: secretion, uptake, and reuptake of 5-HT, that could interfere with 5-HT levels and in this way contribute to the generation of pain. As an experimental model, we used isolated rat peritoneal mast cells and incubated them with selected TCAs (clomipramine, amitriptyline, doxepin, and imipramine under different experimental conditions. 5-HT release, uptake, and reuptake were determined spectrofluorometrically. We showed that TCAs were able to inhibit 5-HT secretion from mast cells, as well as uptake of exogenous 5-HT and reuptake of secreted 5-HT back into mast cells. The effects of TCAs were concentration dependent; higher concentrations of TCAs inhibited the secretion of 5-HT induced by compound 48/80, whereas lower concentrations of TCAs inhibited 5-HT uptake. The most effective TCA was halogenated clomipramine. As TCAs are well introduced in chronic pain treatment, the insight into mechanisms of action is important for an understanding of their effect in various pain conditions.

Monoamine depletion by reuptake inhibitors

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Hinz M

2011-10-01

offers a novel and unified explanation for the waning of response seen after a reuptake inhibitor is started, independent of a drug or placebo etiology.Keywords: reuptake inhibitor, depletion, tachyphylaxis, relapse, serotonin, dopamine

ROLE OF SEROTONIN IN FISH REPRODUCTION

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Parvathy ePrasad

2015-06-01

Full Text Available The neuroendocrine mechanism regulates reproduction through the hypothalamo-pituitary-gonadal (HPG axis which is evolutionarily conserved in vertebrates. The HPG axis is regulated by a variety of internal as well as external factors. Serotonin, a monoamine neurotransmitter, is involved in a wide range of reproductive functions. In mammals, serotonin regulates sexual behaviours, gonadotropin release and gonadotropin-release hormone (GnRH secretion. However, the serotonin system in teleost may play unique role in the control of reproduction as the mechanism of reproductive control in teleosts is not always the same as in the mammalian models. In fish, the serotonin system is also regulated by natural environmental factors as well as chemical substances. In particular, selective serotonin reuptake inhibitors (SSRIs are commonly detected as pharmaceutical contaminants in the natural environment. Those factors may influence fish reproductive functions via the serotonin system. This review summarizes the functional significance of serotonin in the teleosts reproduction.

In vitro anti-Candida activity of selective serotonin reuptake inhibitors against fluconazole-resistant strains and their activity against biofilm-forming isolates.

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Costa Silva, Rose Anny; da Silva, Cecília Rocha; de Andrade Neto, João Batista; da Silva, Anderson Ramos; Campos, Rosana Sousa; Sampaio, Letícia Serpa; do Nascimento, Francisca Bruna Stefany Aires; da Silva Gaspar, Brenda; da Cruz Fonseca, Said Gonçalves; Josino, Maria Aparecida Alexandre; Grangeiro, Thalles Barbosa; Gaspar, Danielle Macedo; de Lucena, David Freitas; de Moraes, Manoel Odorico; Cavalcanti, Bruno Coêlho; Nobre Júnior, Hélio Vitoriano

2017-06-01

Recent research has shown broad antifungal activity of the classic antidepressants selective serotonin reuptake inhibitors (SSRIs). This fact, combined with the increased cross-resistance frequency of the genre Candida regarding the main treatment today, fluconazole, requires the development of novel therapeutic strategies. In that context, this study aimed to assess the antifungal potential of fluoxetine, sertraline, and paroxetine against fluconazole-resistant Candida spp. planktonic cells, as well as to assess the mechanism of action and the viability of biofilms treated with fluoxetine. After 24 h, the fluconazole-resistant Candida spp. strains showed minimum inhibitory concentration (MIC) in the ranges of 20-160 μg/mL for fluoxetine, 10-20 μg/mL for sertraline, and 10-100.8 μg/mL for paroxetine by the broth microdilution method (M27-A3). According to our data by flow cytometry, each of the SSRIs cause fungal death after damaging the plasma and mitochondrial membrane, which activates apoptotic signaling pathways and leads to dose-dependant cell viability loss. Regarding biofilm-forming isolates, the fluoxetine reduce mature biofilm of all the species tested. Therefore, it is concluded that SSRIs are capable of inhibit the growth in vitro of Candida spp., both in planktonic form, as biofilm, inducing cellular death by apoptosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anhedonia in depressed patients on treatment with selective serotonin reuptake inhibitor anti-depressant--A two-centered study in Malaysia.

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Yee, Anne; Chin, Soo Cheng; Hashim, Aili Hanim bt; Harbajan Singh, Manveen Kaur A P; Loh, Huai Seng; Sulaiman, Ahmad Hatim; Ng, Chong Guan

2015-01-01

Anhedonia is the reduced ability to experience pleasure. It is a core symptom of depression and is particularly difficult to treat. This study aims to compare the level of anhedonia between depressed patients on anti-depressants and healthy subjects. A total of 111 depressed patients on selective serotonin reuptake inhibitor (SSRI) and 82 healthy subjects were recruited from the outpatient psychiatric services at two major general hospitals in a cross-sectional study. Subjects were assessed using the Mini International Neuropsychiatric Interview 5.0.0 or MINI, Beck's Depression Index (BDI), and Snaith-Hamilton Pleasure Scale (SHAPS). Relevant personal and sociodemographic information were also collected. There was a significant association between educational level and SHAPS-M scores (P depressed subjects treated with anti-depressant compared with the healthy subjects, after adjusting the confounding factors, BDI score, and educational level. Anhedonia often persists in depressed patients despite on SSRI anti-depressant treatment.

[Selective serotonin reuptake inhibitors in the therapy of various types of endogenous depressions].

Science.gov (United States)

Panteleeva, G P; Abramova, L I; Korenev, A N

2000-01-01

In order to specify differential indications for the use of selective serotonin reuptake inhibitors (SSRI) their therapeutic effect was investigated in apathic-adynamic, melancholic and anxious depressions. Group of 151 patients received monotherapy with one of SSRI-drugs: citalopram--22 patients (mean daily dosage--27.4 mg), paroxetine--47 patients (23 mg), sertraline--19 patients (107 mg), fluvoxamine--28 patients (162 mg), fluoxetine--35 patients (20 mg). The state of the patients was estimated 5 times during 42 days of therapy by clinical estimations and according to Hamilton Depression Scale (HAM-D). Therapeutic effects of the drugs were determined according to the degree of reduction of the total HAM-D scores and they were considered as "significant" (a reduction of the scores by 50% and more), "moderate" (by 21-49%), and "insignificant" (by 1-20%). Positive antidepressive effect, including "significant" was obtained in the case of the use of all the drugs studied. Differential evaluation of the three components of antidepressive activity (thymoleptic, sedative-anxiolytic, and stimulative) according to the degrees and data of expression of drugs' therapeutic effect has allowed to determine indications for the therapy of endogenous depressions by each of SSRI: to recommend cytalopram for the treatment of various types of depressive states mainly, for anxious and apatho-adynamic types; paroxetin--for treatment of melancholic depressions as well as for anxious and apatho-dynamic ones; sertralin++--for depression with anxiety and fobic disorders; fluvoxamine--for melancholic and anxious depression; fluoxetine--for apatho-adynamic depressions.

Serotonin syndrome:case report and current concepts.

LENUS (Irish Health Repository)

Fennell, J

2005-05-01

Selective serotonin reuptake inhibitors (SSRI\\'s) are increasingly being used as the first line therapeutic agent for the depression. It is therefore not unusual to see a case of overdose with these agents. More commonly an adverse drug reaction may be seen among the older patients who are particularly vulnerable to the serotonin syndrome due to multiple co-morbidity and polypharmacy. The clinical picture of serotonin syndrome (SS) is non-specific and there is no confirmatory test. SS may go unrecognized because it is often mistaken for a viral illness, anxiety, neurological disorder or worsening psychiatric condition.

Plasma cytokine profiles in depressed patients who fail to respond to selective serotonin reuptake inhibitor therapy.

LENUS (Irish Health Repository)

O'Brien, Sinead M

2012-02-03

OBJECTIVE: Approximately 30% of patients with depression fail to respond to a selective serotonin reuptake inhibitor (SSRI). Few studies have attempted to define these patients from a biological perspective. Studies suggest that overall patients with depression show increased production of proinflammatory cytokines. We examined pro- and anti-inflammatory cytokine levels in patients who were SSRI resistant. METHODS: Plasma concentrations of IL-6, IL-8, IL-10, TNF-alpha and sIL-6R were measured with enzyme linked immunosorbent assays (ELISA) in DSM-1V major depressives who were SSRI resistant, in formerly SSRI resistant patients currently euthymic and in healthy controls. RESULTS: Patients with SSRI-resistant depression had significantly higher production of the pro-inflammatory cytokines IL-6 (p=0.01) and TNF-alpha (p=0.004) compared to normal controls. Euthymic patients who were formerly SSRI resistant had proinflammatory cytokine levels which were similar to the healthy subject group. Anti-inflammatory cytokine levels did not differ across the 3 groups. CONCLUSION: Suppression of proinflammatory cytokines does not occur in depressed patients who fail to respond to SSRIs and is necessary for clinical recovery.

Moderation of antidepressant response by the serotonin transporter gene

DEFF Research Database (Denmark)

Huezo-Diaz, Patricia; Uher, Rudolf; Smith, Rebecca

2009-01-01

Background: There have been conflicting reports on whether the length polymorphism in the promoter of the serotonin transporter gene (5-HTTLPR) moderates the antidepressant effects of selective serotonin reuptake inhibitors (SSRIs). We hypothesised that the pharmacogenetic effect of 5-HTTLPR...... the serotonin transporter gene were genotyped in 795 adults with moderate-to-severe depression treated with escitalopram or nortriptyline in the Genome Based Therapeutic Drugs for Depression (GENDEP) project. Results: The 5-HTTLPR moderated the response to escitalopram, with long-allele carriers improving more...

The Design, Synthesis and Structure-Activity Relationship of Mixed Serotonin, Norepinephrine and Dopamine Uptake Inhibitors

Science.gov (United States)

Chen, Zhengming; Yang, Ji; Skolnick, Phil

The evolution of antidepressants over the past four decades has involved the replacement of drugs with a multiplicity of effects (e.g., TCAs) by those with selective actions (i.e., SSRIs). This strategy was employed to reduce the adverse effects of TCAs, largely by eliminating interactions with certain neurotransmitters or receptors. Although these more selective compounds may be better tolerated by patients, selective drugs, specifically SSRIs, are not superior to older drugs in treating depressed patients as measured by response and remission rates. It may be an advantage to increase synaptic levels of both serotonin and norepinephrine, as in the case of dual uptake inhibitors like duloxetine and venlafaxine. An important recent development has been the emergence of the triple-uptake inhibitors (TUIs/SNDRIs), which inhibit the uptake of the three neurotransmitters most closely linked to depression: serotonin, norepinephrine, and dopamine. Preclinical studies and clinical trials indicate that a drug inhibiting the reuptake of all three of these neurotransmitters could produce more rapid onset of action and greater efficacy than traditional antidepressants. This review will detail the medicinal chemistry involved in the design, synthesis and discovery of mixed serotonin, norepinephrine and dopamine transporter uptake inhibitors.

Use of antidepressants during pregnancy and the risk of pregnancy-induced hypertension

NARCIS (Netherlands)

Van Loveren, Fianne MAM; Boekema, Monique; Hak, Eelko; Bos, Jens HJ; Aarnoudse, Jan G; Schuiling-Veninga, Catharina CM

2014-01-01

Background: Pregnancy-induced hypertension (PIH) is possibly caused by an increased activity of the sympatic nervous system. Previous studies have suggested that inhibition of the re-uptake of serotonin and norepinephrine by selective serotonin re-uptake inhibitors (SSRIs) and tricyclic

Selective serotonin reuptake inhibitors and the risk of hepatocellular carcinoma in hepatitis B virus-infected patients

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Chang CM

2017-11-01

Full Text Available Chia-Ming Chang,1–3 Ming-Shun Hsieh,1–4 Tsung-Chieh Yang,3,5 Vivian Chia-Rong Hsieh,6 Jen-Huai Chiang,7 Hsien-Hao Huang,1,3 Chorng-Kuang How,1,3 Sung-Yuan Hu,8 David Hung-Tsang Yen1,3 1Department of Emergency Medicine, Taipei Veterans General Hospital, 2Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University College of Public Health, 3College of Medicine, National Yang-Ming University, Taipei, 4Department of Emergency Medicine, 5Division of Gastroenterology, Department of Internal Medicine, Taipei Veterans General Hospital, Taoyuan Branch, Taoyuan, 6Department of Health Services Administration, 7Management Office for Health Data, China Medical University, 8Department of Emergency Medicine, Taichung Veterans General Hospital, Taichung, Taiwan, Republic of China Background: This study aimed to investigate the association between the use of selective serotonin reuptake inhibitors (SSRIs and the risk of hepatocellular carcinoma (HCC in patients with chronic hepatitis B virus (HBV infection.Methods: We conducted a population-based cohort study by using claims data from the Taiwan National Health Insurance Research Database (NHIRD. The study cohort comprised 1380 newly diagnosed HBV-infected patients with SSRI use who were frequency matched by age, sex, liver cirrhosis, and index year with HBV-infected patients without SSRI use in the comparison cohort. Each patient case was followed from 2000 to 2012 to identify incident HCC cases. Cox proportional hazards regression was performed to evaluate the association between SSRI use and HCC risk. The further sensitivity analysis used case-control study design. A total of 9070 HCC subjects retrieved from NHIRD, and equal non-HCC subjects were analyzed after matching for age and sex.Results: We identified 9 and 24 HCC cases in the study and comparison cohorts during the follow-up period of 7056 and 6845 person-years, respectively. The incidence rate of HCC was 1.28 and 3

Short-term use of serotonin reuptake inhibitors and risk of upper gastrointestinal bleeding.

Science.gov (United States)

Wang, Yen-Po; Chen, Yung-Tai; Tsai, Chia-Fen; Li, Szu-Yuan; Luo, Jiing-Chyuan; Wang, Shuu-Jiun; Tang, Chao-Hsiun; Liu, Chia-Jen; Lin, Han-Chieh; Lee, Fa-Yauh; Chang, Full-Young; Lu, Ching-Liang

2014-01-01

The association between selective serotonin receptor inhibitors (SSRIs) and risk of upper gastrointestinal bleeding remains controversial. Previous studies have generally evaluated the issue for approximately 3 months, even though the SSRI-mediated inhibition of platelet serotonin concentrations occurs within 7-14 days. The authors explored the risk of upper gastrointestinal bleeding after short-term SSRI exposure by a case-crossover design. The records of psychiatric inpatients with upper gastrointestinal bleeding were retrieved from the Taiwan National Health Insurance Database (1998-2009). Rates of antidepressant use were compared for case and control periods with time windows of 7, 14, and 28 days. The adjusted self-matched odds ratios from a conditional logistic regression model were used to determine the association between SSRI use and upper gastrointestinal bleeding. A total of 5,377 patients with upper gastrointestinal bleeding were enrolled. The adjusted odds ratio for the risk of upper gastrointestinal bleeding after SSRI exposure was 1.67 (95% CI=1.23-2.26) for the 7-day window, 1.84 (95% CI=1.42-2.40) for the 14-day window, and 1.67 (95% CI=1.34-2.08) for the 28-day window. SSRIs with high and intermediate, but not low, affinity for serotonin transporter were associated with upper gastrointestinal bleeding. An elevated risk of upper gastrointestinal bleeding after SSRI exposure was seen in male but not female patients. Short-term SSRI use (7-28 days) is significantly associated with upper gastrointestinal bleeding. Gender differences may exist in the relationship between SSRI use and upper gastrointestinal bleeding. Physicians should carefully monitor signs of upper gastrointestinal bleeding even after short-term exposure to SSRIs, as is done with nonsteroidal anti-inflammatory drugs and aspirin.

Serotonin 6 receptor controls Alzheimer's disease and depression.

Science.gov (United States)

Yun, Hyung-Mun; Park, Kyung-Ran; Kim, Eun-Cheol; Kim, Sanghyeon; Hong, Jin Tae

2015-09-29

Alzheimer's disease (AD) and depression in late life are one of the most severe health problems in the world disorders. Serotonin 6 receptor (5-HT6R) has caused much interest for potential roles in AD and depression. However, a causative role of perturbed 5-HT6R function between two diseases was poorly defined. In the present study, we found that a 5-HT6R antagonist, SB271036 rescued memory impairment by attenuating the generation of Aβ via the inhibition of γ-secretase activity and the inactivation of astrocytes and microglia in the AD mouse model. It was found that the reduction of serotonin level was significantly recovered by SB271036, which was mediated by an indirect regulation of serotonergic neurons via GABA. Selective serotonin reuptake inhibitor (SSRI), fluoxetine significantly improved cognitive impairment and behavioral changes. In human brain of depression patients, we then identified the potential genes, amyloid beta (A4) precursor protein-binding, family A, member 2 (APBA2), well known AD modulators by integrating datasets from neuropathology, microarray, and RNA seq. studies with correlation analysis tools. And also, it was demonstrated in mouse models and patients of AD. These data indicate functional network of 5-HT6R between AD and depression.

The six most widely used selective serotonin reuptake inhibitors decrease androgens and increase estrogens in the H295R cell line

DEFF Research Database (Denmark)

Hansen, Cecilie Hurup; Larsen, Lizette Weber; Sørensen, Amalie Møller

2017-01-01

Selective serotonin reuptake inhibitors (SSRIs) used as first line of treatment in major depressive disorder (MDD) are known to exert negative effects on the endocrine system and fertility. The aim of the present study was to investigate the possible endocrine disrupting effect of six SSRIs...... in the pathway. Furthermore, all SSRIs relatively increased the estrogen/androgen ratio, indicating stimulating effects on the aromatase. Our study demonstrates the potential of SSRIs to interfere with steroid production in the H295R cells around Cmax levels and indicates that these drugs should be investigated...... validated LC-MS/MS method. All 6 SSRIs were found to exert endocrine disrupting effects on steroid hormone synthesis at concentrations just around Cmax. Although the mechanisms of disruption were all different, they all resulted in decreased testosterone levels, some due to effects on CYP17, some earlier...

Selective serotonin reuptake inhibitors versus placebo in patients with major depressive disorder. A systematic review with meta-analysis and Trial Sequential Analysis

DEFF Research Database (Denmark)

Jakobsen, Janus Christian; Katakam, Kiran Kumar; Schou, Anne

2017-01-01

-term effects. Conclusions: SSRIs might have statistically significant effects on depressive symptoms, but all trials were at high risk of bias and the clinical significance seems questionable. SSRIs significantly increase the risk of both serious and non-serious adverse events. The potential small beneficial......Background: The evidence on selective serotonin reuptake inhibitors (SSRIs) for major depressive disorder is unclear. Methods: Our objective was to conduct a systematic review assessing the effects of SSRIs versus placebo, 'active' placebo, or no intervention in adult participants with major...... depressive disorder. We searched for eligible randomised clinical trials in The Cochrane Library's CENTRAL, PubMed, EMBASE, PsycLIT, PsycINFO, Science Citation Index Expanded, clinical trial registers of Europe and USA, websites of pharmaceutical companies, the U.S. Food and Drug Administration (FDA...

Escitalopram, an antidepressant with an allosteric effect at the serotonin transporter--a review of current understanding of its mechanism of action.

Science.gov (United States)

Zhong, Huailing; Haddjeri, Nasser; Sánchez, Connie

2012-01-01

Escitalopram is a widely used antidepressant for the treatment of patients with major depression. It is the pure S-enantiomer of racemic citalopram. Several clinical trials and meta-analyses indicate that escitalopram is quantitatively more efficacious than many other antidepressants with a faster onset of action. This paper reviews current knowledge about the mechanism of action of escitalopram. The primary target for escitalopram is the serotonin transporter (SERT), which is responsible for serotonin (or 5-hydroxytryptamine [5-HT]) reuptake at the terminals and cell bodies of serotonergic neurons. Escitalopram and selective serotonin reuptake inhibitors bind with high affinity to the 5-HT binding site (orthosteric site) on the transporter. This leads to antidepressant effects by increasing extracellular 5-HT levels which enhance 5-HT neurotransmission. SERT also has one or more allosteric sites, binding to which modulates activity at the orthosteric binding site but does not directly affect 5-HT reuptake by the transporter. In vitro studies have shown that through allosteric binding, escitalopram decreases its own dissociation rate from the orthosteric site on the SERT. R-citalopram, the nontherapeutic enantiomer in citalopram, is also an allosteric modulator of SERT but can inhibit the actions of escitalopram by interfering negatively with its binding. Both nonclinical studies and some clinical investigations have demonstrated the cellular, neurochemical, neuroadaptive, and neuroplastic changes induced by escitalopram with acute and chronic administration. The findings from binding, neurochemical, and neurophysiological studies may provide a mechanistic rationale for the clinical difference observed with escitalopram compared to other antidepressant therapies.

Serotonin and noradrenaline reuptake inhibitors (SNRIs) for fibromyalgia.

Science.gov (United States)

Welsch, Patrick; Üçeyler, Nurcan; Klose, Petra; Walitt, Brian; Häuser, Winfried

2018-02-28

Fibromyalgia is a clinically defined chronic condition of unknown etiology characterized by chronic widespread pain that often co-exists with sleep disturbances, cognitive dysfunction and fatigue. People with fibromyalgia often report high disability levels and poor quality of life. Drug therapy, for example, with serotonin and noradrenaline reuptake inhibitors (SNRIs), focuses on reducing key symptoms and improving quality of life. This review updates and extends the 2013 version of this systematic review. To assess the efficacy, tolerability and safety of serotonin and noradrenaline reuptake inhibitors (SNRIs) compared with placebo or other active drug(s) in the treatment of fibromyalgia in adults. For this update we searched CENTRAL, MEDLINE, Embase, the US National Institutes of Health and the World Health Organization (WHO) International Clinical Trials Registry Platform for published and ongoing trials and examined the reference lists of reviewed articles, to 8 August 2017. We selected randomized, controlled trials of any formulation of SNRIs against placebo or any other active treatment of fibromyalgia in adults. Three review authors independently extracted data, examined study quality, and assessed risk of bias. For efficacy, we calculated the number needed to treat for an additional beneficial outcome (NNTB) for pain relief of 50% or greater and of 30% or greater, patient's global impression to be much or very much improved, dropout rates due to lack of efficacy, and the standardized mean differences (SMD) for fatigue, sleep problems, health-related quality of life, mean pain intensity, depression, anxiety, disability, sexual function, cognitive disturbances and tenderness. For tolerability we calculated number needed to treat for an additional harmful outcome (NNTH) for withdrawals due to adverse events and for nausea, insomnia and somnolence as specific adverse events. For safety we calculated NNTH for serious adverse events. We undertook meta

Antidepressant stimulation of CDP-diacylglycerol synthesis does not require monoamine reuptake inhibition

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Aboukhatwa Marwa A

2010-01-01

Full Text Available Abstract Background Recent studies demonstrate that diverse antidepressant agents increase the cellular production of the nucleolipid CDP-diacylglycerol and its synthetic derivative, phosphatidylinositol, in depression-relevant brain regions. Pharmacological blockade of downstream phosphatidylinositide signaling disrupted the behavioral antidepressant effects in rats. However, the nucleolipid responses were resistant to inhibition by serotonin receptor antagonists, even though antidepressant-facilitated inositol phosphate accumulation was blocked. Could the neurochemical effects be additional to the known effects of the drugs on monoamine transmitter transporters? To examine this question, we tested selected agents in serotonin-depleted brain tissues, in PC12 cells devoid of serotonin transporters, and on the enzymatic activity of brain CDP-diacylglycerol synthase - the enzyme that catalyzes the physiological synthesis of CDP-diacylglycerol. Results Imipramine, paroxetine, and maprotiline concentration-dependently increased the levels of CDP-diacylglycerol and phosphatidylinositides in PC12 cells. Rat forebrain tissues depleted of serotonin by pretreatment with p-chlorophenylalanine showed responses to imipramine or maprotiline that were comparable to respective responses from saline-injected controls. With fluoxetine, nucleolipid responses in the serotonin-depleted cortex or hippocampus were significantly reduced, but not abolished. Each drug significantly increased the enzymatic activity of CDP-diacylglycerol synthase following incubations with cortical or hippocampal brain tissues. Conclusion Antidepressants probably induce the activity of CDP-diacylglycerol synthase leading to increased production of CDP-diacylglycerol and facilitation of downstream phosphatidylinositol synthesis. Phosphatidylinositol-dependent signaling cascades exert diverse salutary effects in neural cells, including facilitation of BDNF signaling and neurogenesis. Hence

The effect of sibutramine, a serotonin-norepinephrine reuptake inhibitor, on platelets and fibrin networks of male Sprague-Dawley rats: a descriptive study.

Science.gov (United States)

van der Schoor, Ciska; Oberholzer, Hester Magdalena; Bester, Megan Jean; van Rooy, Mia-Jeanne

2014-12-01

Sibutramine is used in the treatment of obesity due to its ability to influence feelings of hunger and satiety by inhibiting the re-uptake of serotonin and noradrenalin in the central nervous system (CNS). Sibutramine use has been associated with numerous adverse events in particular cardiovascular complications possibly due to the formation of thrombi. This ultrastructural descriptive study investigated the effect of sibutramine on blood coagulation, specifically the effect on morphology of platelets and fibrin networks using scanning electron microscopy. Male Sprague-Dawley rats treated with either a recommended therapeutic dose [low dosage 1.32 mg/kg] or a toxicological higher dose [high dosage 13.2 mg/kg] of sibutramine for 28 days were used and compared to control animals. Blood samples were collected and plasma smears were prepared for platelet evaluation. Following the addition of thrombin to the plasma samples, the morphology of the fibrin clots was evaluated. Platelet evaluation by scanning electron microscopy revealed morphology typical of a prothrombotic state with a characteristic excessive platelet activation in both low-dose (LD) and high-dose (HD) rats. The fibrin clots of sibutramine-treated rats, LD and HD revealed fused thick fibers with thin fibers forming a net-like structure over the thick fibers which differ considerably from the organized structure of the control animals. It can be concluded that sibutramine alters the ultrastructure of platelets and fibrin networks creating a prothrombotic state.

Pharmacokinetics and tolerability of DA-8031, a novel selective serotonin reuptake inhibitor for premature ejaculation in healthy male subjects

Directory of Open Access Journals (Sweden)

Shin D

2017-03-01

Full Text Available Dongseong Shin,1 SeungHwan Lee,2 Sojeong Yi,2 Seo Hyun Yoon,2 Joo-Youn Cho,2 Mi Young Bahng,3 In-Jin Jang,2 Kyung-Sang Yu2 1Clinical Trials Center, Gachon University Gil Medical Center, Incheon, 2Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, 3Department of Product Development, Dong-A ST, Seoul, Korea Objective: DA-8031 is a selective serotonin reuptake inhibitor under development for the treatment of premature ejaculation. This is the first-in-human study aimed at evaluating the pharmacokinetics and tolerability of DA-8031 and its metabolites (M1, M2, M4, and M5 in the plasma and urine after administration of a single oral dose in healthy male subjects.Methods: A dose block-randomized, double-blind, placebo-controlled, single ascending dose study was conducted. Subjects received either placebo or a single dose of DA-8031 at 5, 10, 20, 40, 60, 80, or 120 mg. DA-8031 and its four metabolites were analyzed in the plasma and urine for pharmacokinetic evaluation. The effect of genetic polymorphisms of cytochrome-P450 (CYP enzymes on the pharmacokinetics of DA-8031 was evaluated.Results: After a single dose, plasma DA-8031 reached the maximum concentration at a median of 2–3 h and was eliminated with terminal elimination half-life of 17.9–28.7 h. The mean renal clearance was 3.7–5.6 L/h. Dose-proportional pharmacokinetics was observed over the dose range of 20–80 mg. Among the metabolites, M4 had the greatest plasma concentration, followed by M5 and M1. Subjects with CYP2D6 intermediate metabolizer had significantly greater dose-normalized Cmax and AUC0–t of DA-8031 as well as smaller metabolic ratios than those subjects with CYP2D6 extensive metabolizer. The most common adverse events were nausea, dizziness, and headache, and no serious adverse events were reported.Conclusion: In conclusion, the systemic exposure of DA-8031 was increased proportionally to the dose within 20

Comparison of paroxetine and dapoxetine, a novel selective serotonin reuptake inhibitor in the treatment of premature ejaculation

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Abdulmuttalip Simsek

2014-10-01

Full Text Available Dapoxetine hydrochloride is a selective serotonin reuptake inhibitor and the first drug approved for the on-demand treatment of premature ejaculation (PE. Our objective in this study was to characterize the efficacy of on-demand dapoxetine (30 and 60 mg and daily paroxetine (20 mg usage in treating PE. We conducted a 1 month study involving a total of 150 patients. Patients were divided into three groups of 50. Group 1 were treated with on-demand dapoxetine (30 mg, Group 2 with on-demand dapoxetine (60 mg and Group 3 with daily paroxetine (20 mg. Our outcome measurement was increased from baseline intravaginal ejaculatory latency time (IELT after treatment. The IELT increased from baseline to posttreatment by 117%, 117% and 170% in the paroxetine group (P 0.05, while the 60 mg dapoxetine group had a larger posttreatment IELT increase compared with the 30 mg dapoxetine (P < 0.05 and paroxetine (P < 0.01 groups. Dapoxetine (60 mg 1-3 h before planned intercourse is a very effective treatment modality for PE. However, an on-demand dose of 30 mg dapoxetine is no more effective than the currently prescribed paroxetine treatment.

Selective serotonin reuptake inhibitors and venlafaxine in pregnancy: Changes in drug disposition.

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Andreas Austgulen Westin

Full Text Available Pregnancy may cause changes in drug disposition. The clinical consequences may be profound and even counterintuitive; in some cases pregnant women may need more than twice their usual drug dose in order to maintain therapeutic drug levels. For antidepressants, evidence on drug disposition in pregnancy is scarce. The aim of this study was to determine the effects of pregnancy on serum levels of selective serotonin reuptake inhibitors (SSRIs and venlafaxine in a large and naturalistic patient material, in order to provide tentative dose recommendations for pregnant women.Using patient data from two routine therapeutic drug monitoring (TDM services in Norway with linkage to the national birth registry, dose-adjusted serum drug concentrations of SSRIs and venlafaxine during pregnancy were compared to the women's own baseline (non-pregnant values, using a linear mixed model.Overall, the TDM databases contained 196,726 serum concentration measurements from 54,393 women. After data linkage and drug selection (SSRIs or venlafaxine only, we identified 367 analyses obtained from a total of 290 pregnancies in 281 women, and 420 baseline observations from the same women. Serum concentrations in the third trimester were significantly lower than baseline for paroxetine (-51%; 95% confidence interval [CI], -66%, -30%; p<0.001, fluvoxamine (-56%; CI, -75%, -23%; p = 0.004 and citalopram (-24%; CI, -38%, -7%; p = 0,007, and higher than baseline for sertraline (+68%; CI, +37%, +106%; p<0.001. For escitalopram, fluoxetine and venlafaxine concentrations did not change significantly.For paroxetine and fluvoxamine the pronounced decline in maternal drug serum concentrations in pregnancy may necessitate a dose increase of about 100% during the third trimester in order to maintain stable concentrations. For fluoxetine, venlafaxine, citalopram, escitalopram and sertraline, the present study indicates that dose adjustments are generally not necessary during pregnancy.

Dose-dependent inhibition of CYP1A2, CYP2C19 and CYP2D6 by citalopram, fluoxetine, fluvoxamine and paroxetine

DEFF Research Database (Denmark)

Jeppesen, U; Gram, L F; Vistisen, K

1996-01-01

OBJECTIVE: The purpose of this pharmacokinetic study was to investigate the dose-dependent inhibition of model substrates for CYP2D6, CYP2C19 and CYP1A2 by four marketed selective serotonin reuptake inhibitors (SSRIs): citalopram, fluoxetine, fluvoxamine and paroxetine. METHODS: The study...

Affective startle modulation : psychopharmacological studies on the roles of CRF and serotonin in the regulation of emotions

NARCIS (Netherlands)

Bijlsma, E.Y.

2010-01-01

Major depression and anxiety disorders are the most prevalent psychiatric disorders. The high co-morbidity and strong overlap in symptoms suggest that neurobiological mechanisms may also overlap. Two neuromodulators have received much attention. First, serotonin: Selective serotonin reuptake

Genetics of premenstrual syndrome: investigation of specific serotonin receptor polymorphisms

OpenAIRE

Dhingra, Vandana

2014-01-01

Premenstrual dysphoric disorder (PMDD) is a distressing and disabling syndrome causing a significant degree of impairment on daily functioning and interpersonal relationships in 3-8% of the women. With the convincing evidence that PMS is inheritable and that serotonin is important in the pathogenesis of PMS, and failure of initial studies to demonstrate significant associations between key genes controlling the synthesis, reuptake and catabolism of serotonin and PMDD, the main aim of this the...

Effects of chronic treatment with fluvoxamine and paroxetine during adolescence on serotonin-related behavior in adult male rats.

NARCIS (Netherlands)

Jong, T.R. de; Snaphaan, L.J.A.E.; Pattij, T.; Veening, J.G.; Waldinger, M.D.; Cools, A.R.; Olivier, B.

2006-01-01

Selective Serotonin Reuptake Inhibitors (SSRIs) are designed to treat adults, but are increasingly prescribed for adolescents. SSRIs might cause permanent changes in serotonin-related behavior in adolescents, since their serotonergic system is still developing. Male Wistar rats were treated with

The effects of maternal depression and maternal selective serotonin reuptake inhibitor exposure on the offspring

Directory of Open Access Journals (Sweden)

Jocelien DA Olivier

2013-05-01

Full Text Available It has been estimated that 20% of pregnant women suffer from depression and it is well documented that maternal depression can have long-lasting effects on the child. Currently, common treatment for maternal depression has been the selective serotonin reuptake inhibitor medications (SSRIs which are used by 2-3% of pregnant women in the Nordic countries and by up to 10% of pregnant women in the United States. Antidepressants cross the placenta and are transferred to the fetus, thus, the question arises as to whether children of women taking antidepressants are at risk for altered neurodevelopmental outcomes and, if so, whether the risks are due to SSRI medication exposure or to the underlying maternal depression. This review considers the effects of maternal depression and SSRI exposure on offspring development in both clinical and preclinical populations. As it is impossible in humans to study the effects of SSRIs without taking into account the possible underlying effects of maternal depression (healthy pregnant women do not take SSRIs, animal models are of great value. For example, rodents can be used to determine the effects of maternal depression and/or perinatal SSRI exposure on offspring outcomes. Unraveling the joint (or separate effects of maternal depression and SSRI exposure will provide more insights into the risks or benefits of SSRI exposure during gestation and will help women make informed decisions about using SSRIs during pregnancy.

Single photon emission computed tomography before and after treatment of anxiety using a selective serotonin reuptake inhibitor

International Nuclear Information System (INIS)

Warwick, J.M.; Heerden, B.B. van; Stein, D.J.; Niehaus, D.J.H.; Seedat, S.; Linden, G. van der; Harvey, B.A.

2002-01-01

Background: The selective serotonin reuptake inhibitors (SSRIs) are currently recommended as first line medications for a number of different anxiety disorders, including obsessive-compulsive disorder (OCD), posttraumatic stress disorder (PTSD), and social anxiety disorder (social phobia) (SAD). This raises the question of what effects these agents have on the functional neuroanatomy of anxiety disorders. Methods: Single photon emission computed tomography (SPECT) brain scanning was undertaken in patients with OCD, PTSD, and SAD before and after treatment with citalopram, the most selective of the SSRIs. Statistical parametric mapping (SPM) was used to compare scans (pre- vs post-medication, and responders vs nonresponders) in the combined group of subjects. Results: Citalopram pharmacotherapy resulted in significant deactivation within anterior and superior cingulate and left hippocampus. Deactivation within the anterior cingulate, left paracingular cortex, and right inferior frontal cortex was more marked in treatment responders. Baseline activation did not, however, predict response to pharmacotherapy. Conclusion: Although each of the anxiety disorders may be mediated by different neurocircuits, there are some overlaps in the functional neuroanatomy of their response to SSRI treatment. The current data is consistent with previous work demonstrating the importance of limbic circuits in this spectrum of disorders. These play a crucial role in cognitive-affective processing, and are innervated by serotonergic neurons

The effect of selective serotonin reuptake inhibitors in healthy first-degree relatives of patients with major depressive disorder - an experimental medicine blinded controlled trial

DEFF Research Database (Denmark)

Knorr, Ulla Benedichte

2012-01-01

.37). In univariate analyses, no statistically significant correlations were found between change in the primary and secondary outcomes, respectively, and the covariates age, sex, Hamilton depression score 17-items, and plasma escitalopram levels. In conclusion, the present trial does not support an effect......The mechanisms of action for selective serotonin re-uptake in-hibitors (SSRI) in depressed patients remain widely unknown. The serotonergic neurotransmitter system and the hypothalamic-pituitary-adrenal (HPA) system may interact. Further, the serotonergic neurotransmitter system seems closely...... linked to personality and cognition. It is not known if SSRIs have a direct effect on the HPA system, personality or cognition that is independent of their effect on depression. Thus, healthy individuals with a genetic liability for depression represent a group of particular interest when investigating...

Anterior cingulate serotonin 1B receptor binding is associated with emotional response inhibition

DEFF Research Database (Denmark)

da Cunha-Bang, Sofi; Hjordt, Liv Vadskjær; Dam, Vibeke Høyrup

2017-01-01

-offender controls, completed an emotional Go/NoGo task requiring inhibition of prepotent motor responses to emotional facial expressions. We also measured cerebral serotonin 1B receptor (5-HT1BR) binding with [11C]AZ10419369 positron emission tomography within regions of the frontal cortex. We hypothesized that 5......-HT1BR would be positively associated with false alarms (failures to inhibit nogo responses) in the context of aversive (angry and fearful) facial expressions. Across groups, we found that frontal cortex 5-HT1BR binding was positively correlated with false alarms when angry faces were go stimuli......Serotonin has a well-established role in emotional processing and is a key neurotransmitter in impulsive aggression, presumably by facilitating response inhibition and regulating subcortical reactivity to aversive stimuli. In this study 44 men, of whom 19 were violent offenders and 25 were non...

Microautoradiography of [123I]ADAM in mice treated with fluoxetine and serotonin reuptake inhibitors

International Nuclear Information System (INIS)

Ye, X.-X.; Chen, J.-C.; Liu, R.-S.; Wey, S.-P.; Lee, J.-S.; Chen, C.-C.; Fu, Y.-K.; Ting, Gann; Hwang, J.-J.

2004-01-01

A radiopharmaceutical, 123 I-labeled 2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine ([ 123 I]ADAM), has been developed recently for evaluation of how serotonin transporters (SERT) function in the brain. However, the detailed biodistribution and specific binding in certain brain areas are not well investigated. In this study, both phosphor plate imaging and microautoradiography were applied to explore the binding characteristics of [ 123 I]ADAM in SERT neurons. The effect of two psychotropics and one narcotic on the binding of [ 123 I]ADAM to SERT was also studied. Fluoxetine and desipramine, both are psychotropics and specific SERT ligands and decreased the affinity of [ 123 I]ADAM, while p-chloroamphetamine (PCA), a narcotic, destroyed most of serotonergic neurons, as well as reducing the concentration of serotonin and the number of SERT in the brain as shown by the biodistribution of [ 123 I]ADAM. Significant and selective accumulation of [ 123 I]ADAM in the areas from midbrain to brain stem in normal mice with maximum target-to-background ratio was found at 90 minutes postinjection. A rapid clearance of [ 131 I]ADAM at 120 minutes postinjection was found in the CA1, CA3 and ThN brain areas. In addition, the inhibition effect on binding ability of [ 123 I]ADAM to SERT by the psychotropics and the narcotic was found to have the order of: PCA > fluoxetine > desipramine

A single nucleotide polymorphism in the human serotonin transporter introduces a new site for N-linked glycosylation

DEFF Research Database (Denmark)

Rasmussen, Trine Nygaard; Plenge, Per; Bay, Tina

2009-01-01

The human serotonin transporter (hSERT) is responsible for reuptake of serotonin (5-HT) from the synaptic cleft and is target for antidepressant medicine. Differential hSERT activity caused by genetic polymorphisms is believed to affect the risk of developing depression and, moreover, to affect t...

Increasing the risk of spontaneous abortion and major malformations in newborns following use of serotonin reuptake inhibitors during pregnancy: A systematic review and updated meta-analysis

Directory of Open Access Journals (Sweden)

Nikfar Shekoufeh

2012-11-01

Full Text Available Abstract Selective serotonin reuptake inhibitors (SSRIs are the most frequently used antidepressants during pregnancy. There are conflicting results about their influence on pregnancy outcomes. The goal of this study was to update our previous meta-analysis about pregnancy outcomes following exposure to SSRIs. For this purpose, all relevant databases were searched from 1990 to March 2012 for studies investigating the pregnancy outcomes following exposure to any therapeutic dosage of any SSRI (fluoxetine, paroxetine, citalopram, escitalopram, sertraline, fluvoxamine during pregnancy. Types of outcome investigated were spontaneous abortion, major malformations, cardiovascular malformations, and minor malformations. A total of 25 studies met our criteria and were included in the meta-analysis. The odds ratio (OD values are 1.87 (95% CI: 1.5 to 2.33, P

Positive regulation of raphe serotonin neurons by serotonin 2B receptors.

Science.gov (United States)

Belmer, Arnauld; Quentin, Emily; Diaz, Silvina L; Guiard, Bruno P; Fernandez, Sebastian P; Doly, Stéphane; Banas, Sophie M; Pitychoutis, Pothitos M; Moutkine, Imane; Muzerelle, Aude; Tchenio, Anna; Roumier, Anne; Mameli, Manuel; Maroteaux, Luc

2018-06-01

Serotonin is a neurotransmitter involved in many psychiatric diseases. In humans, a lack of 5-HT 2B receptors is associated with serotonin-dependent phenotypes, including impulsivity and suicidality. A lack of 5-HT 2B receptors in mice eliminates the effects of molecules that directly target serotonergic neurons including amphetamine derivative serotonin releasers, and selective serotonin reuptake inhibitor antidepressants. In this work, we tested the hypothesis that 5-HT 2B receptors directly and positively regulate raphe serotonin neuron activity. By ex vivo electrophysiological recordings, we report that stimulation by the 5-HT 2B receptor agonist, BW723C86, increased the firing frequency of serotonin Pet1-positive neurons. Viral overexpression of 5-HT 2B receptors in these neurons increased their excitability. Furthermore, in vivo 5-HT 2B -receptor stimulation by BW723C86 counteracted 5-HT 1A autoreceptor-dependent reduction in firing rate and hypothermic response in wild-type mice. By a conditional genetic ablation that eliminates 5-HT 2B receptor expression specifically and exclusively from Pet1-positive serotonin neurons (Htr2b 5-HTKO mice), we demonstrated that behavioral and sensitizing effects of MDMA (3,4-methylenedioxy-methamphetamine), as well as acute behavioral and chronic neurogenic effects of the antidepressant fluoxetine, require 5-HT 2B receptor expression in serotonergic neurons. In Htr2b 5-HTKO mice, dorsal raphe serotonin neurons displayed a lower firing frequency compared to control Htr2b lox/lox mice as assessed by in vivo extracellular recordings and a stronger hypothermic effect of 5-HT 1A -autoreceptor stimulation was observed. The increase in head-twitch response to DOI (2,5-dimethoxy-4-iodoamphetamine) further confirmed the lower serotonergic tone resulting from the absence of 5-HT 2B receptors in serotonin neurons. Together, these observations indicate that the 5-HT 2B receptor acts as a direct positive modulator of serotonin Pet1

Synthesis of [11C]dapoxetine·HCl, a serotonin re-uptake inhibitor: biodistribution in rat and preliminary PET imaging in the monkey

International Nuclear Information System (INIS)

Livni, E.; Satterlee, W.; Robey, R.L.

1994-01-01

[ 11 C]Dapoxetine · HCl, S-(+)-N,N-dimethyl-a-[2-(naphthalenyloxy)ethyl] benzenemethanamine hydrochloride, a potent serotonin re-uptake inhibitor was prepared from its mono-methyl precursor, S-(+)-N-methyl-a-[2-(naphthalenyloxy)ethyl]benzene methanamine hydrochloride. Biodistribution was determined in rats at 5, 30 and 60 min after injection and preliminary PET studies were performed in a Rhesus monkey. 11 CH 3 I was bubbled into a solution of S-(+)-N-methyl-α-[2-(naphthalenyloxy)ethyl]benzene methanamine hydrochloride (3.0 mg in DMSO) and the mixture was heated at 110 o C for 8 min. [ 11 C]Dapoxetine · HCl was purified by HPLC on a C 18 cartridge eluted with MeOH: phosphate buffer, pH 7.2 (75:25) with a 10% yield (end of synthesis). The time required for the synthesis was 40 min, from the end of bombardment. Radiochemical purity of the final product was > 99% and specific activity was routinely > 400 mCi/μmol [EOS]. (author)

The effect of antenatal depression and selective serotonin reuptake inhibitor treatment on nerve growth factor signaling in human placenta.

Directory of Open Access Journals (Sweden)

Helena Kaihola

Full Text Available Depressive symptoms during pregnancy are common and may have impact on the developing child. Selective serotonin reuptake inhibitors (SSRIs are the most prescribed antidepressant treatment, but unfortunately, these treatments can also negatively affect the behavioral development and health of a child during pregnancy. In addition, serotonin (5-HT exerts neurotrophic actions with thus far not fully known effects in the offspring. The neurotrophic growth factor (NGF is involved in neuronal cell survival and differentiation, and altered placenta levels have been found to increase the risk for pregnancy complications, similar to those found in women treated with SSRIs. We therefore investigated whether the NGF signaling pathway was altered in the placenta from women treated with SSRIs (n = 12 and compared them with placenta from depressed (n = 12 and healthy mothers (n = 12. Results from immunohistochemical stainings revealed that placental NGF protein levels of SSRI-treated women were increased in both trophoblasts and endothelial cells compared with depressed and control women. In addition, downstream of the NGF receptor TrkA, increased levels of the signaling proteins ROCK2 and phosphorylated Raf-1 were found in stromal cells and a tendency towards increased levels of ROCK2 in trophoblasts and endothelial cells in SSRI-treated women when compared to healthy controls. SSRI-treated women also displayed increased levels of phosphorylated ROCK2 in all placental cell types studied in comparison with depressed and control women. Interestingly, in placental endothelial cells from depressed women, NGF levels were significantly lower compared to control women, but ROCK2 levels were increased compared with control and SSRI-treated women. Taken together, these results show that the NGF signaling and downstream pathways in the placenta are affected by SSRI treatment and/or antenatal depression. This might lead to an altered placental function, although the

Variation in serotonin neurotransmission genes affects neural activation during response inhibition in adolescents and young adults with ADHD and healthy controls

NARCIS (Netherlands)

Van Rooij, Daan; Hartman, Catharina A.; Van Donkelaar, Marjolein M. J.; Bralten, Janita; Von Rhein, Daniel; Hakobjan, Marina; Franke, Barbara; Heslenfeld, Dirk J.; Oosterlaan, Jaap; Rommelse, Nanda; Buitelaar, Jan K.; Hoekstra, Pieter J.

2015-01-01

Objectives. Deficits in response inhibition have been associated with attention-deficit/hyperactivity disorder (ADHD). Given the role of serotonin in ADHD and impulsivity, we postulated that genetic variants within the serotonin pathway might influence response inhibition. Methods. We measured

Selective serotonin reuptake inhibitors for fibromyalgia syndrome

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Brian Walitt

Full Text Available ABSTRACT BACKGROUND: Fibromyalgia is a clinically well-defined chronic condition with a biopsychosocial aetiology. Fibromyalgia is characterized by chronic widespread musculoskeletal pain, sleep problems, cognitive dysfunction, and fatigue. Patients often report high disability levels and poor quality of life. Since there is no specific treatment that alters the pathogenesis of fibromyalgia, drug therapy focuses on pain reduction and improvement of other aversive symptoms. OBJECTIVES: To assess the benefits and harms of selective serotonin reuptake inhibitors (SSRIs in the treatment of fibromyalgia. METHODS: Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 5, MEDLINE (1966 to June 2014, EMBASE (1946 to June 2014, and the reference lists of reviewed articles. Selection criteria: We selected all randomized, double-blind trials of SSRIs used for the treatment of fibromyalgia symptoms in adult participants. We considered the following SSRIs in this review: citalopram, fluoxetine, escitalopram, fluvoxamine, paroxetine, and sertraline. Data collection and analysis: Three authors extracted the data of all included studies and assessed the risks of bias of the studies. We resolved discrepancies by discussion. MAIN RESULTS: The quality of evidence was very low for each outcome. We downgraded the quality of evidence to very low due to concerns about risk of bias and studies with few participants. We included seven placebo-controlled studies, two with citalopram, three with fluoxetine and two with paroxetine, with a median study duration of eight weeks (4 to 16 weeks and 383 participants, who were pooled together. All studies had one or more sources of potential major bias. There was a small (10% difference in patients who reported a 30% pain reduction between SSRIs (56/172 (32.6% and placebo (39/171 (22.8% risk difference (RD 0.10, 95% confidence interval (CI 0.01 to 0.20; number needed to treat for an

Selective serotonin reuptake inhibitors for fibromyalgia syndrome

Science.gov (United States)

Walitt, Brian; Urrútia, Gerard; Nishishinya, María Betina; Cantrell, Sarah E; Häuser, Winfried

2016-01-01

Background Fibromyalgia is a clinically well-defined chronic condition with a biopsychosocial aetiology. Fibromyalgia is characterized by chronic widespread musculoskeletal pain, sleep problems, cognitive dysfunction, and fatigue. Patients often report high disability levels and poor quality of life. Since there is no specific treatment that alters the pathogenesis of fibromyalgia, drug therapy focuses on pain reduction and improvement of other aversive symptoms. Objectives The objective was to assess the benefits and harms of selective serotonin reuptake inhibitors (SSRIs) in the treatment of fibromyalgia. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 5), MEDLINE (1966 to June 2014), EMBASE (1946 to June 2014), and the reference lists of reviewed articles. Selection criteria We selected all randomized, double-blind trials of SSRIs used for the treatment of fibromyalgia symptoms in adult participants. We considered the following SSRIs in this review: citalopram, fluoxetine, escitalopram, fluvoxamine, paroxetine, and sertraline. Data collection and analysis Three authors extracted the data of all included studies and assessed the risks of bias of the studies. We resolved discrepancies by discussion. Main results The quality of evidence was very low for each outcome. We downgraded the quality of evidence to very low due to concerns about risk of bias and studies with few participants. We included seven placebo-controlled studies, two with citalopram, three with fluoxetine and two with paroxetine, with a median study duration of eight weeks (4 to 16 weeks) and 383 participants, who were pooled together. All studies had one or more sources of potential major bias. There was a small (10%) difference in patients who reported a 30% pain reduction between SSRIs (56/172 (32.6%)) and placebo (39/171 (22.8%)) risk difference (RD) 0.10, 95% confidence interval (CI) 0.01 to 0.20; number needed to treat for an additional

SEP-225289 serotonin and dopamine transporter occupancy: a PET study.

Science.gov (United States)

DeLorenzo, Christine; Lichenstein, Sarah; Schaefer, Karen; Dunn, Judith; Marshall, Randall; Organisak, Lisa; Kharidia, Jahnavi; Robertson, Brigitte; Mann, J John; Parsey, Ramin V

2011-07-01

SEP-225289 is a novel compound that, based on in vitro potencies for transporter function, potentially inhibits reuptake at dopamine, norepinephrine, and serotonin transporters. An open-label PET study was conducted during the development of SEP-225289 to investigate its dopamine and serotonin transporter occupancy. Different single doses of SEP-225289 were administered to healthy volunteers in 3 cohorts: 8 mg (n = 7), 12 mg (n = 5), and 16 mg (n = 7). PET was performed before and approximately 24 h after oral administration of SEP-225289, to assess occupancy at trough levels. Dopamine and serotonin transporter occupancies were estimated from PET using (11)C-N-(3-iodoprop-2E-enyl)-2β-carbomethoxy-3β-(4-methylphenyl)nortropane ((11)C-PE2I) and (11)C-N,N-dimethyl-2-(2-amino-4-cyanophenylthio)benzylamine ((11)C-DASB), respectively. Plasma concentration of SEP-225289 was assessed before ligand injection, and subjects were monitored for adverse events. Average dopamine and serotonin transporter occupancies increased with increasing doses of SEP-225289. Mean dopamine and serotonin transporter occupancies were 33% ± 11% and 2% ± 13%, respectively, for 8 mg; 44% ± 4% and 9% ± 10%, respectively, for 12 mg; and 49% ± 7% and 14% ± 15%, respectively, for 16 mg. On the basis of the relationship between occupancy and plasma concentration, dopamine transporter IC(50) (the plasma concentration of drug at 50% occupancy) was determined (4.5 ng/mL) and maximum dopamine transporter occupancy was extrapolated (85%); however, low serotonin transporter occupancy prevented similar serotonin transporter calculations. No serious adverse events were reported. At the doses evaluated, occupancy of the dopamine transporter was significantly higher than that of the serotonin transporter, despite similar in vitro potencies, confirming that, in addition to in vitro assays, PET occupancy studies can be instrumental to the drug development process by informing early decisions about

5-HT2C receptors in the BNST are necessary for the enhancement of fear learning by selective serotonin reuptake inhibitors.

Science.gov (United States)

Pelrine, Eliza; Pasik, Sara Diana; Bayat, Leyla; Goldschmiedt, Debora; Bauer, Elizabeth P

2016-12-01

Selective serotonin reuptake inhibitors (SSRIs) are widely prescribed to treat anxiety and depression, yet they paradoxically increase anxiety during initial treatment. Acute administration of these drugs prior to learning can also enhance Pavlovian cued fear conditioning. This potentiation has been previously reported to depend upon the bed nucleus of the stria terminalis (BNST). Here, using temporary inactivation, we confirmed that the BNST is not necessary for the acquisition of cued or contextual fear memory. Systemic administration of the SSRI citalopram prior to fear conditioning led to an upregulation of the immediate early gene Arc (activity-regulated cytoskeleton-associated protein) in the oval nucleus of the BNST, and a majority of these neurons expressed the 5-HT2C receptor. Finally, local infusions of a 5-HT2C receptor antagonist directly into the oval nucleus of the BNST prevented the fear memory-enhancing effects of citalopram. These findings highlight the ability of the BNST circuitry to be recruited into gating fear and anxiety-like behaviors. Copyright © 2016 Elsevier Inc. All rights reserved.

Antidepressant Specificity of Serotonin Transporter Suggested by Three LeuT-SSRI Structures

Energy Technology Data Exchange (ETDEWEB)

Zhou, Z.; Zhen, J; Karpowich, N; Law, C; Reith, M; Wang, D

2009-01-01

Sertraline and fluoxetine are selective serotonin re-uptake inhibitors (SSRIs) that are widely prescribed to treat depression. They exert their effects by inhibiting the presynaptic plasma membrane serotonin transporter (SERT). All SSRIs possess halogen atoms at specific positions, which are key determinants for the drugs' specificity for SERT. For the SERT protein, however, the structural basis of its specificity for SSRIs is poorly understood. Here we report the crystal structures of LeuT, a bacterial SERT homolog, in complex with sertraline, R-fluoxetine or S-fluoxetine. The SSRI halogens all bind to exactly the same pocket within LeuT. Mutation at this halogen-binding pocket (HBP) in SERT markedly reduces the transporter's affinity for SSRIs but not for tricyclic antidepressants. Conversely, when the only nonconserved HBP residue in both norepinephrine and dopamine transporters is mutated into that found in SERT, their affinities for all the three SSRIs increase uniformly. Thus, the specificity of SERT for SSRIs is dependent largely on interaction of the drug halogens with the protein's HBP.

The serotonin transporter in rhesus monkey brain: comparison of DASB and citalopram binding sites

International Nuclear Information System (INIS)

Zeng Zhizhen; Chen, T.-B.; Miller, Patricia J.; Dean, Dennis; Tang, Y.S.; Sur, Cyrille; Williams, David L.

2006-01-01

We have characterized the interaction of the serotonin transporter ligand [ 3 H]-N,N-dimethyl-2-(2-amino-4-cyanophenylthio)-benzylamine (DASB) with rhesus monkey brain in vitro using tissue homogenate binding and autoradiographic mapping. [ 3 H]-DASB, a tritiated version of the widely used [ 11 C] positron emission tomography tracer, was found to selectively bind to a single population of sites with high affinity (K d =0.20±0.04 nM). The serotonin transporter density (B max ) obtained for rhesus frontal cortex was found to be 66±8 fmol/mg protein using [ 3 H]-DASB, similar to the B max value obtained using the reference radioligand [ 3 H]-citalopram, a well-characterized and highly selective serotonin reuptake inhibitor (83±22 fmol/mg protein). Specific binding sites of both [ 3 H]-DASB and [ 3 H]-citalopram were similarly and nonuniformly distributed throughout the rhesus central nervous system, in a pattern consistent with serotonin transporter localization reported for human brain. Regional serotonin transporter densities, estimated from optical densities of the autoradiographic images, were well correlated between the two radioligands. Finally, DASB and fluoxetine showed dose-dependent full inhibition of [ 3 H]-citalopram binding in a competition autoradiographic study, with K i values in close agreement with those obtained from rhesus brain homogenates. This side-by-side comparison of [ 3 H]-DASB and [ 3 H]-citalopram binding sites in rhesus tissue homogenates and in adjacent rhesus brain slices provides additional support for the use of [ 11 C]-DASB to assess the availability and distribution of serotonin transporters in nonhuman primates

A Dualistic Conformational Response to Substrate Binding in the Human Serotonin Transporter Reveals a High Affinity State for Serotonin*

Science.gov (United States)

Bjerregaard, Henriette; Severinsen, Kasper; Said, Saida; Wiborg, Ove; Sinning, Steffen

2015-01-01

Serotonergic neurotransmission is modulated by the membrane-embedded serotonin transporter (SERT). SERT mediates the reuptake of serotonin into the presynaptic neurons. Conformational changes in SERT occur upon binding of ions and substrate and are crucial for translocation of serotonin across the membrane. Our understanding of these conformational changes is mainly based on crystal structures of a bacterial homolog in various conformations, derived homology models of eukaryotic neurotransmitter transporters, and substituted cysteine accessibility method of SERT. However, the dynamic changes that occur in the human SERT upon binding of ions, the translocation of substrate, and the role of cholesterol in this interplay are not fully elucidated. Here we show that serotonin induces a dualistic conformational response in SERT. We exploited the substituted cysteine scanning method under conditions that were sensitized to detect a more outward-facing conformation of SERT. We found a novel high affinity outward-facing conformational state of the human SERT induced by serotonin. The ionic requirements for this new conformational response to serotonin mirror the ionic requirements for translocation. Furthermore, we found that membrane cholesterol plays a role in the dualistic conformational response in SERT induced by serotonin. Our results indicate the existence of a subpopulation of SERT responding differently to serotonin binding than hitherto believed and that membrane cholesterol plays a role in this subpopulation of SERT. PMID:25614630

Efficacy of bupropion and the selective serotonin reuptake inhibitors in the treatment of major depressive disorder with high levels of anxiety (anxious depression): a pooled analysis of 10 studies.

Science.gov (United States)

Papakostas, George I; Stahl, Stephen M; Krishen, Alok; Seifert, Cheryl A; Tucker, Vivian L; Goodale, Elizabeth P; Fava, Maurizio

2008-08-01

The goal of this work was to compare the efficacy of the norepinephrine and dopamine reuptake inhibitor bupropion with the selective serotonin reuptake inhibitors (SSRIs) in the treatment of major depressive disorder with high levels of anxiety (anxious depression). Ten double-blind, randomized studies from 1991 through 2006 were combined (N = 2122). Anxious depression was defined as a 17-item Hamilton Rating Scale for Depression (HAM-D-17) anxiety-somatization factor score >or= 7. Among patients with anxious depression (N = 1275), response rates were greater following SSRI than bupropion treatment according to the HAM-D-17 (65.4% vs. 59.4%, p = .03) and the Hamilton Rating Scale for Anxiety (61.5% vs. 54.5%, p = .03). There was also a greater reduction in HAM-D-17 mean +/- SD scores (-14.1 +/- 7.6 vs. -13.2 +/- 7.9, p = .03) and a trend toward statistical significance for a greater reduction in HAM-A mean +/- SD scores (-10.5 +/- 7.4 vs. -9.6 +/- 7.6, p = .05) in favor of SSRI treatment among patients with anxious depression. There was no statistically significant difference in efficacy between bupropion and the SSRIs among patients with moderate/low levels of anxiety. There appears to be a modest advantage for the SSRIs compared to bupropion in the treatment of anxious depression (6% difference in response rates). Using the number-needed-to-treat (NNT) statistic as 1 indicator of clinical significance, nearly 17 patients would need to be treated with an SSRI than with bupropion in order to obtain 1 additional responder. This difference falls well above the limit of NNT = 10, which was suggested by the United Kingdom's National Institute of Clinical Excellence. Nevertheless, the present work is of theoretical interest because it provides preliminary evidence suggesting a central role for serotonin in the regulation of symptoms of negative affect such as anxiety.

Selective serotonin reuptake inhibitor sertraline inhibits voltage ...

Indian Academy of Sciences (India)

2016-10-04

Oct 4, 2016 ... der, social anxiety disorder, and obsessive-compulsive dis- order. Because of .... to describe the interaction kinetics between the drugs and channels (Park et al. ..... of the human cardiac hKv1.5 channel. Circ. Res. 77 575–583.

An improved automated synthesis and in vivo evaluation of PET radioligand for serotonin re-uptake sites. [11C]McN5652X

International Nuclear Information System (INIS)

Sasaki, Masahiro; Suhara, Tetsuya; Suzuki, Kazutoshi; Kubodera, Akiko.

1996-01-01

Carbon-11 labeled serotonin (5-HT) re-uptake inhibitor, [ 11 C]McN5 652X ((6S,10bR)-trans-( + )-1,2,3,5,6,10b-hexahydro-6-[4-(methylthio)phenyl]pyrrolo-[2,1-a]-isoquinoline), has recently been reported to be favorable for studying human 5-HT re-uptake site by positron emission tomography (PET) because of its rapid and high specific binding characteristics as radioligands. [ 11 C]McN5652X has been synthesized by S-methylation of the corresponding des-methyl precursor A with [ 11 C]iodomethane. One serious disadvantage of this procedure, however, is the lack of stability of A. The improved method for the synthesis of A has been desired. We have found that the decomposition of A is significantly reduced by adding a protecting agent for SH groups, dithiothreitol (DTT), into the reaction medium immediately after the demethylation of McN5652X. By using this stabilized precursor A, we have developed an automated procedure giving [ 11 C]McN5652X with 98.6±0.4% radiochemical purity in high specific activity (181.3±7.4GBq/μmol). Preclinical evaluation of the produ ct was carried out by injecting the solution of [ 11 C]McN5652X obtained by this procedure into mice. [ 11 C]McN5652X showed the high accumulation into mouse thalamus, striatum and cerebral cortex, organs known to have high level of 5-HT receptor density, after intravenous injection. Human PET studies also showed the high uptakes of this radioligand into the thalamus, striatum and midbrain

Are selective serotonin reuptake inhibitors safe for drivers? What is the evidence?

Science.gov (United States)

Ravera, Silvia; Ramaekers, Johannes G; de Jong-van den Berg, Lolkje T W; de Gier, Johan J

2012-05-01

Selective serotonin reuptake inhibitors (SSRIs) are widely used medications to treat several psychiatric diseases and, above all, depression. They seem to be as effective as older antidepressants but have a different adverse effect profile. Despite their favorable safety profile, little is known about their influence on traffic safety. To conduct a literature review to summarize the current evidence on the role of SSRIs in traffic safety, particularly concerning undesirable effects that could potentially impair fitness to drive, experimental and pharmacoepidemiologic studies on driving impairment, 2 existing categorization systems for driving-impairing medications, and the European legislative procedures for assessing fitness to drive before issuing a driver's license and driving under the influence of medicines. The article search was performed in the following electronic databases: MEDLINE, PsycINFO, ScienceDirect, and SafetyLit. The English-language scientific literature was searched using key words such as SSRIs and psychomotor performance, car crash or traffic accident, and adverse effects. For inclusion in this review, papers had to be full-text articles, refer to possible driving-related adverse effects, and be experimental or pharmacoepidemiologic studies on SSRIs and traffic accident risks. No restrictions concerning publication year were applied. Ten articles were selected as background information on driving-related adverse effects, and 15 articles were selected regarding experimental and pharmacoepidemiologic work. Regarding SSRI adverse effects, the most reported undesirable effects referring to driving impairment were anxiety, agitation, sleep disturbances, headache, increased risk of suicidal behavior, and deliberate self-harm. Regarding the remaining issues addressed in this article, inconsistencies were found between the outcomes of the selected experimental and epidemiologic studies and between the 2 existing categorization systems under

Occupancy of serotonin transporters in the amygdala by paroxetine in association with attenuation of left amygdala activation by negative faces in major depressive disorder

NARCIS (Netherlands)

Ruhe, Henricus G.; Koster, Michiel; Booij, Jan; van Herk, Marcel; Veltman, Dick J.; Schene, Aart H.

2014-01-01

Amygdala hyperactivation in major depressive disorder (MDD) might be attenuated by selective serotonin reuptake inhibitors (SSRls), but the working mechanism remains unclear. We hypothesized that higher amygdala serotonin transporter (SERT) occupancy by paroxetine results in greater attenuation of

Occupancy of serotonin transporters in the amygdala by paroxetine in association with attenuation of left amygdala activation by negative faces in major depressive disorder

NARCIS (Netherlands)

Ruhé, Henricus G.; Koster, Michiel; Booij, Jan; van Herk, Marcel; Veltman, Dick J.; Schene, Aart H.

2014-01-01

Amygdala hyperactivation in major depressive disorder (MDD) might be attenuated by selective serotonin reuptake inhibitors (SSRIs), but the working mechanism remains unclear. We hypothesized that higher amygdala serotonin transporter (SERT) occupancy by paroxetine results in greater attenuation of

Rapid Onset of the Effects of Combined Selective Serotonin Reuptake Inhibitors and Electroacupuncture on Primary Depression: A Meta-Analysis.

Science.gov (United States)

Zhang, Yue; Qu, Shan-shan; Zhang, Ji-ping; Sun, Ya-ling; Liu, Wei-lu; Xie, Ling; Huang, Yong; Chen, Jun-qi

2016-01-01

To evaluate the efficacy and safety of combined selective serotonin reuptake inhibitors (SSRIs) and electroacupuncture therapies for the early treatment of primary depression. Randomized controlled trials (RCTs) were analyzed to compare therapy combining SSRIs and electroacupuncture to SSRI therapy alone. The RCTs were identified by searching, among others, PubMed, the Cochrane Library, the Chinese National Knowledge Infrastructure, the Chongqing VIP database for Chinese Technical Periodicals, WANFANG DATA, and the Chinese Biological Medical Literature Database. Scores from Self-Rated Depression Scale (SDS), the Hamilton Depression Scale (HAMD), the Side Effect Rating Scale (SERS), and the Treatment Emergent Symptom Scale (TESS) were analyzed and coded by two independent investigators and used to evaluate the safety and efficacy of treatment. Statistical analyses were performed using RevMan 5.2 software. Six RCTs were analyzed. The meta-analysis revealed that the combined therapy of SSRIs and electroacupuncture were associated with superior scores on the HAMD, SDS, and SERS measures compared with SSRIs alone after 1-4 weeks of treatment: HAMD scores, mean difference (MD)(1 week), 2.32 (95% confidence interval [CI](1 week), 1.47-3.16, p(1 week)electroacupuncture therapies is more efficient than treatments with SSRIs alone and leads to a better and earlier control of depressive symptoms.

Serotonin-related pathways and developmental plasticity: relevance for psychiatric disorders

Science.gov (United States)

Dayer, Alexandre

2014-01-01

Risk for adult psychiatric disorders is partially determined by early-life alterations occurring during neural circuit formation and maturation. In this perspective, recent data show that the serotonin system regulates key cellular processes involved in the construction of cortical circuits. Translational data for rodents indicate that early-life serotonin dysregulation leads to a wide range of behavioral alterations, ranging from stress-related phenotypes to social deficits. Studies in humans have revealed that serotonin-related genetic variants interact with early-life stress to regulate stress-induced cortisol responsiveness and activate the neural circuits involved in mood and anxiety disorders. Emerging data demonstrate that early-life adversity induces epigenetic modifications in serotonin-related genes. Finally, recent findings reveal that selective serotonin reuptake inhibitors can reinstate juvenile-like forms of neural plasticity, thus allowing the erasure of long-lasting fear memories. These approaches are providing new insights on the biological mechanisms and clinical application of antidepressants. PMID:24733969

Five Patients With Burning Mouth Syndrome in Whom an Antidepressant (Serotonin-Noradrenaline Reuptake Inhibitor) Was Not Effective, but Pregabalin Markedly Relieved Pain.

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Ito, Mikiko; Tokura, Tatsuya; Yoshida, Keizo; Nagashima, Wataru; Kimura, Hiroyuki; Umemura, Eri; Tachibana, Masako; Miyauchi, Tomoya; Kobayashi, Yuka; Arao, Munetaka; Ozaki, Norio; Kurita, Kenichi

2015-01-01

Burning mouth syndrome (BMS) causes idiopathic pain or a burning sensation in clinically normal oral mucosa. Burning mouth syndrome is a chronic disease with an unknown etiology. Burning mouth syndrome is also idiopathic, and a consensus regarding diagnosis/treatment has not been reached yet. Recent studies have supported the suggestion that BMS is a neuropathic pain disorder in which both the peripheral and central nervous systems are involved. Tricyclic antidepressants (nortriptyline and amitriptyline), serotonin-noradrenaline reuptake inhibitors (SNRIs) (duloxetine and milnacipran), and antiepileptic drugs, potential-dependent calcium channel α2δ subunit ligands (gabapentine and pregabalin), are currently recommended as the first-choice drugs for neuropathic pain. In this study, we report 5 patients with BMS in whom there was no response to SNRI (milnacipran or duloxetine), or administration was discontinued because of adverse reactions, but in whom pregabalin therapy markedly reduced or led to the disappearance of pain in a short period. Pregabalin, whose mechanism of action differs from that of SNRIs, may become a treatment option for BMS patients who are not responsive to or are resistant to SNRIs.

Anxiety and depression with neurogenesis defects in exchange protein directly activated by cAMP 2-deficient mice are ameliorated by a selective serotonin reuptake inhibitor, Prozac

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Zhou, L; Ma, S L; Yeung, P K K; Wong, Y H; Tsim, K W K; So, K F; Lam, L C W; Chung, S K

2016-01-01

Intracellular cAMP and serotonin are important modulators of anxiety and depression. Fluoxetine, a selective serotonin reuptake inhibitor (SSRI) also known as Prozac, is widely used against depression, potentially by activating cAMP response element-binding protein (CREB) and increasing brain-derived neurotrophic factor (BDNF) through protein kinase A (PKA). However, the role of Epac1 and Epac2 (Rap guanine nucleotide exchange factors, RAPGEF3 and RAPGEF4, respectively) as potential downstream targets of SSRI/cAMP in mood regulations is not yet clear. Here, we investigated the phenotypes of Epac1 (Epac1−/−) or Epac2 (Epac2−/−) knockout mice by comparing them with their wild-type counterparts. Surprisingly, Epac2−/− mice exhibited a wide range of mood disorders, including anxiety and depression with learning and memory deficits in contextual and cued fear-conditioning tests without affecting Epac1 expression or PKA activity. Interestingly, rs17746510, one of the three single-nucleotide polymorphisms (SNPs) in RAPGEF4 associated with cognitive decline in Chinese Alzheimer's disease (AD) patients, was significantly correlated with apathy and mood disturbance, whereas no significant association was observed between RAPGEF3 SNPs and the risk of AD or neuropsychiatric inventory scores. To further determine the detailed role of Epac2 in SSRI/serotonin/cAMP-involved mood disorders, we treated Epac2−/− mice with a SSRI, Prozac. The alteration in open field behavior and impaired hippocampal cell proliferation in Epac2−/− mice were alleviated by Prozac. Taken together, Epac2 gene polymorphism is a putative risk factor for mood disorders in AD patients in part by affecting the hippocampal neurogenesis. PMID:27598965

Microautoradiography of [{sup 123}I]ADAM in mice treated with fluoxetine and serotonin reuptake inhibitors

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Ye, X.-X.; Chen, J.-C.; Liu, R.-S.; Wey, S.-P.; Lee, J.-S.; Chen, C.-C.; Fu, Y.-K.; Ting, Gann; Hwang, J.-J. E-mail: jjhwang@ym.edu.tw

2004-07-01

A radiopharmaceutical, {sup 123}I-labeled 2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine ([{sup 123}I]ADAM), has been developed recently for evaluation of how serotonin transporters (SERT) function in the brain. However, the detailed biodistribution and specific binding in certain brain areas are not well investigated. In this study, both phosphor plate imaging and microautoradiography were applied to explore the binding characteristics of [{sup 123}I]ADAM in SERT neurons. The effect of two psychotropics and one narcotic on the binding of [{sup 123}I]ADAM to SERT was also studied. Fluoxetine and desipramine, both are psychotropics and specific SERT ligands and decreased the affinity of [{sup 123}I]ADAM, while p-chloroamphetamine (PCA), a narcotic, destroyed most of serotonergic neurons, as well as reducing the concentration of serotonin and the number of SERT in the brain as shown by the biodistribution of [{sup 123}I]ADAM. Significant and selective accumulation of [{sup 123}I]ADAM in the areas from midbrain to brain stem in normal mice with maximum target-to-background ratio was found at 90 minutes postinjection. A rapid clearance of [{sup 131}I]ADAM at 120 minutes postinjection was found in the CA1, CA3 and ThN brain areas. In addition, the inhibition effect on binding ability of [{sup 123}I]ADAM to SERT by the psychotropics and the narcotic was found to have the order of: PCA > fluoxetine > desipramine.

The serotonin transporter undergoes constitutive internalization and is primarily sorted to late endosomes and lysosomal degradation

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Rahbek-Clemmensen, Troels; Bay, Tina; Eriksen, Jacob

2014-01-01

The serotonin transporter (SERT) plays a critical role in regulating serotonin signaling by mediating reuptake of serotonin from the extracellular space. The molecular and cellular mechanisms controlling SERT levels in the membrane remain poorly understood. To study trafficking of surface resident...... SERT, two functional epitope tagged variants were generated. Fusion of a FLAG-tagged one-transmembrane segment protein Tac to the SERT N-terminus generated a transporter with an extracellular epitope suited for trafficking studies (TacSERT). Likewise, a construct with an extracellular antibody epitope...

The serotonin transporter in rhesus monkey brain: comparison of DASB and citalopram binding sites

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Zeng Zhizhen [Imaging Department, Merck Research Laboratories, West Point, PA 19486 (United States)]. E-mail: zhizhen_zeng@merck.com; Chen, T.-B. [Imaging Department, Merck Research Laboratories, West Point, PA 19486 (United States); Miller, Patricia J. [Imaging Department, Merck Research Laboratories, West Point, PA 19486 (United States); Dean, Dennis [Labeled Compound Synthesis Group, Drug Metabolism, Merck Research Laboratories, Rahway, NJ 07065-0900 (United States); Tang, Y.S. [Labeled Compound Synthesis Group, Drug Metabolism, Merck Research Laboratories, Rahway, NJ 07065-0900 (United States); Sur, Cyrille [Imaging Department, Merck Research Laboratories, West Point, PA 19486 (United States); Williams, David L. [Imaging Department, Merck Research Laboratories, West Point, PA 19486 (United States)

2006-05-15

We have characterized the interaction of the serotonin transporter ligand [{sup 3}H]-N,N-dimethyl-2-(2-amino-4-cyanophenylthio)-benzylamine (DASB) with rhesus monkey brain in vitro using tissue homogenate binding and autoradiographic mapping. [{sup 3}H]-DASB, a tritiated version of the widely used [{sup 11}C] positron emission tomography tracer, was found to selectively bind to a single population of sites with high affinity (K {sub d}=0.20{+-}0.04 nM). The serotonin transporter density (B {sub max}) obtained for rhesus frontal cortex was found to be 66{+-}8 fmol/mg protein using [{sup 3}H]-DASB, similar to the B {sub max} value obtained using the reference radioligand [{sup 3}H]-citalopram, a well-characterized and highly selective serotonin reuptake inhibitor (83{+-}22 fmol/mg protein). Specific binding sites of both [{sup 3}H]-DASB and [{sup 3}H]-citalopram were similarly and nonuniformly distributed throughout the rhesus central nervous system, in a pattern consistent with serotonin transporter localization reported for human brain. Regional serotonin transporter densities, estimated from optical densities of the autoradiographic images, were well correlated between the two radioligands. Finally, DASB and fluoxetine showed dose-dependent full inhibition of [{sup 3}H]-citalopram binding in a competition autoradiographic study, with K {sub i} values in close agreement with those obtained from rhesus brain homogenates. This side-by-side comparison of [{sup 3}H]-DASB and [{sup 3}H]-citalopram binding sites in rhesus tissue homogenates and in adjacent rhesus brain slices provides additional support for the use of [{sup 11}C]-DASB to assess the availability and distribution of serotonin transporters in nonhuman primates.

Serotonin Toxicity Caused by Moclobemide Too Soon After Paroxetine-Selegiline

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Ming-Ling Wu

2009-08-01

Full Text Available Serotonin toxicity is an iatrogenic complication of serotonergic drug therapy. It is due to an overstimulation of central and peripheral serotonin receptors that lead to neuromuscular, mental and autonomic changes. Moclobemide is a reversible inhibitor of monoamine oxidase (MAO-A, selegiline is an irreversible selective inhibitor of MAO-B, and paroxetine is a selective serotonin reuptake inhibitor. Combined use of these agents is known to cause serotonin toxicity. A 53-year-old woman had been treated with paroxetine and selegiline. After moclobemide was prescribed in place of paroxetine without a washout period, she quickly developed confusion, agitation, ataxia, diaphoresis, tremor, mydriasis, ocular clonus, hyper-reflexia, tachycardia, moderately elevated blood pressure and high fever, symptoms that were consistent with serotonin toxicity. Discontinuation of the drugs, hydration and supportive care were followed by remarkable improvement of baseline status within 3 days. This case demonstrates that serotonin toxicity may occur even with small doses of paroxetine, selegi-line and moclobemide in combination. Physicians managing patients with depression must be aware of the potential for serotonin toxicity and should be able to recognize and treat or, ideally, anticipate and avoid this pharmacodynamically-mediated interaction that may occur between prescribed drugs.

Tratamento farmacológico do transtorno obsessivo-compulsivo

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Carla Marques

2001-10-01

Full Text Available The pharmacotherapy for obsessive-compulsive disorder (OCD has started with clomipramine, a potent non-selective serotonin reuptake inhibitor. Newer drugs that selectively inhibit serotonin reuptake (SSRIs such as fluvoxamine, fluoxetine, paroxetine, and sertraline are also effective and well-tolerated by OCD patients, even in high doses. Efficacy of venlafaxine and citalopram for OCD are under investigation. Randomized controlled trials of OCD pharmacotherapy, as well as positive results found in open trials and case reports are reviewed in this paper. Potent selective serotonin reuptake inhibitors are the pharmacotherapy of choice for OCD. If one SSRI is ineffective, others may be beneficial. OCD is frequently a chronic condition that requires long-term treatment.

An analysis of psychotropic drug sales. Increasing sales of selective serotonin reuptake inhibitors are closely related to number of products.

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Nielsen, Margrethe; Gøtzsche, Peter

2011-01-01

Prescribing of selective serotonin reuptake inhibitors (SSRIs) has increased dramatically. To compare the sales of benzodiazepines and SSRIs within the primary care sector in Denmark and relate changes in usage to number of indications and products on the market. We used data from various sources to establish the sales curves of psychotropic drugs in the period 1970 to 2007, based on the Anatomic Therapeutic Classification system and Defined Daily Doses. Fluctuations in sales of psychotropic drugs that cannot be explained by disease prevalence were caused by changes in sales of the benzodiazepines and SSRIs. We found a decline in the sales of benzodiazepines after a peak in 1986, likely due to the recognition that they cause dependence. From a low level in 1992, we found that the sales of SSRIs increased almost linearly by a factor of 18, up to 44 DDD per 1000 inhabitants, which was closely related to the number of products on the market that increased by a factor of 16. Sales of antidepressant drugs are mainly determined by market availability of products indicating that marketing pressures are playing an important role. Thus the current level of use of SSRIs may not be evidence-based, which is supported by studies showing that the effect of SSRIs has been overestimated.

Serotonin 5HT1A receptor availability and pathological crying after stroke

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Møller, Mette; Andersen, G; Gjedde, A

2007-01-01

OBJECTIVES: Post-stroke depression and pathological crying (PC) implicate an imbalance of serotonergic neurotransmission. We claim that PC follows serotonin depletion that raises the binding potential (p(B)) of the 5-HT(1A) receptor antagonist [carbonyl-(11)C]WAY-100635, which is reversible...... by selective serotonin re-uptake inhibitor (SSRI) treatment. MATERIALS AND METHODS: We PET scanned patients with acute stroke and PC and age-matched control subjects. Maps of receptor availability were generated from the images of eight cortical regions and raphe nuclei. RESULTS: The maps showed highest...

Dependence and withdrawal reactions to benzodiazepines and selective serotonin reuptake inhibitors. How did the health authorities react?

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Nielsen, Margrethe; Hansen, Ebba Holme; Gøtzsche, Peter C

2013-01-01

Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time. Documentary study. We searched the web-sites of the European Medicines Agency and the drug agencies in USA, UK, and Denmark for documents mentioning benzodiazepines or SSRIs. We supplemented with other relevant literature that could contribute to our study. The searches were performed in 2009 in PubMed, Google, BMJ and JAMA. It took many years before the drug regulators acknowledged benzodiazepine dependence and SSRI withdrawal reactions and before the prescribers and the public were informed. Drug regulators relied mainly on the definitions of dependence and withdrawal reactions from the diagnostic psychiatric manuals, which contributed to the idea that SSRIs do not cause dependence, although it is difficult for many patients to stop treatment. In the perspective of a precautionary principle, drug agencies have failed to acknowledge that SSRIs can cause dependence and have minimised the problem with regard to its frequency and severity. In the perspective of a risk management principle, the drug agencies have reacted in concordance with the slowly growing knowledge of adverse drug reactions and have sharpened the information to the prescribers and the public over time. However, solely relying on spontaneous reporting of adverse effects leads to underestimation and delayed information about the problems. Given the experience with the benzodiazepines, we believe the regulatory bodies should have required studies from the manufacturers that could have elucidated the dependence potential of the SSRIs before marketing authorization was granted.

Selective serotonin reuptake inhibitors (SSRIs) for post-partum depression (PPD): a systematic review of randomized clinical trials.

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De Crescenzo, Franco; Perelli, Federica; Armando, Marco; Vicari, Stefano

2014-01-01

The treatment of postpartum depression with selective serotonin reuptake inhibitors (SSRIs) has been claimed to be both efficacious and well tolerated, but no recent systematic reviews have been conducted. A qualitative systematic review of randomized clinical trials on women with postpartum depression comparing SSRIs to placebo and/or other treatments was performed. A comprehensive literature search of online databases, the bibliographies of published articles and grey literature were conducted. Data on efficacy, acceptability and tolerability were extracted and the quality of the trials was assessed. Six randomised clinical trials, comprising 595 patients, met quality criteria for inclusion in the analysis. Cognitive-behavioural intervention, psychosocial community-based intervention, psychodynamic therapy, cognitive behavioural therapy, a second-generation tricyclic antidepressant and placebo were used as comparisons. All studies demonstrated higher response and remission rates among those treated with SSRIs and greater mean changes on depression scales, although findings were not always statistically significant. Dropout rates were high in three of the trials but similar among treatment and comparison groups. In general, SSRIs were well tolerated and trial quality was good. There are few trials, patients included in the trials were not representative of all patients with postpartum depression, dropout rates in three trials were high, and long-term efficacy and tolerability were assessed in only two trials. SSRIs appear to be efficacious and well tolerated in the treatment of postpartum depression, but the available evidence fails to demonstrate a clear superiority over other treatments. © 2013 Elsevier B.V. All rights reserved.

Two-week administration of the combined serotonin-noradrenaline reuptake inhibitor duloxetine augments functioning of mesolimbic incentive processing circuits.

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Ossewaarde, Lindsey; Verkes, Robbert J; Hermans, Erno J; Kooijman, Sabine C; Urner, Maren; Tendolkar, Indira; van Wingen, Guido A; Fernández, Guillén

2011-09-15

Anhedonia and lack of motivation are core symptoms of major depressive disorder (MDD). Neuroimaging studies in MDD patients have shown reductions in reward-related activity in terminal regions of the mesolimbic dopamine (DA) system, such as the ventral striatum. Monoamines have been implicated in both mesolimbic incentive processing and the mechanism of action of antidepressant drugs. However, not much is known about antidepressant effects on mesolimbic incentive processing in humans, which might be related to the effects on anhedonia. To investigate the short-term effects of antidepressants on reward-related activity in the ventral striatum, we investigated the effect of the combined serotonin-norepinephrine reuptake inhibitor duloxetine. Healthy volunteers underwent functional magnetic resonance imaging in a randomized, double-blind, placebo-controlled, crossover study. After taking duloxetine (60 mg once a day) or placebo for 14 days, participants completed a monetary incentive delay task that activates the ventral striatum during reward anticipation. Our results (n = 19) show enhanced ventral striatal responses after duloxetine administration compared with placebo. Moreover, this increase in ventral striatal activity was positively correlated with duloxetine plasma levels. This is the first study to demonstrate that antidepressants augment neural activity in mesolimbic DA incentive processing circuits in healthy volunteers. These effects are likely caused by the increase in monoamine neurotransmission in the ventral striatum. Our findings suggest that antidepressants may alleviate anhedonia by stimulating incentive processing. Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Serotonin reuptake inhibitors and mortality in epilepsy: A linked primary-care cohort study.

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Josephson, Colin B; Gonzalez-Izquierdo, Arturo; Denaxas, Spiros; Fitzpatrick, Natalie K; Sajobi, Tolulope T; Engbers, Jordan D T; Patten, Scott; Jette, Nathalie; Wiebe, Samuel

2017-11-01

Preliminary evidence suggests that serotonin reuptake inhibitor (SRI) use may increase postictal respiratory drive and prevent death. We sought to determine whether SRIs are associated with improved all-cause and possible seizure-specific mortality in patients with epilepsy. Patients with epilepsy and a random 10:1 sample without epilepsy were extracted from The ClinicAl research using LInked Bespoke studies and Electronic health Records (CALIBER) resource. The hazard ratio (HR) of all-cause and possible seizure-specific mortality, treating SRI use as a time-varying covariate, was determined using the date of a second SRI prescription as exposure and in discrete 6-month periods over the entire duration of follow-up. We used Cox regression and competing risk models with Firth correction to calculate the HR. We controlled for age, sex, depression, comorbidity, (Charlson comorbidity index) and socioeconomic status (Index of Multiple Deprivation). We identified 2,718,952 eligible patients in CALIBER, of whom 16,379 (0.60%) had epilepsy. Median age and follow-up were 44 (interquartile range [IQR] 29-61]) and 6.4 years (IQR 2.4-10.4 years), respectively, and 53% were female. A total of 2,178 patients (13%) had at least two SRI prescriptions. Hazard of all-cause mortality was significantly elevated following a second prescription for an SRI (HR 1.64 95% confidence interval [95% CI] 1.44-1.86; p < 0.001). The HR was similar in 163,778 age, sex, and general practitioner (GP) practice-matched controls without epilepsy. Exposure to an SRI was not associated with seizure-related death (HR 1.08, 95% CI 0.59-1.97; 0.796). There is no evidence in this large population-based cohort that SRIs protect against all-cause mortality or seizure-specific mortality. Rather, SRI use was associated with increased mortality, irrespective of epilepsy, which is probably due to various factors associated with the use of antidepressants. Larger studies with systematically collected clinical

Serotonin and Blood Pressure Regulation

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Morrison, Shaun F.; Davis, Robert Patrick; Barman, Susan M.

2012-01-01

5-Hydroxytryptamine (5-HT; serotonin) was discovered more than 60 years ago as a substance isolated from blood. The neural effects of 5-HT have been well investigated and understood, thanks in part to the pharmacological tools available to dissect the serotonergic system and the development of the frequently prescribed selective serotonin-reuptake inhibitors. By contrast, our understanding of the role of 5-HT in the control and modification of blood pressure pales in comparison. Here we focus on the role of 5-HT in systemic blood pressure control. This review provides an in-depth study of the function and pharmacology of 5-HT in those tissues that can modify blood pressure (blood, vasculature, heart, adrenal gland, kidney, brain), with a focus on the autonomic nervous system that includes mechanisms of action and pharmacology of 5-HT within each system. We compare the change in blood pressure produced in different species by short- and long-term administration of 5-HT or selective serotonin receptor agonists. To further our understanding of the mechanisms through which 5-HT modifies blood pressure, we also describe the blood pressure effects of commonly used drugs that modify the actions of 5-HT. The pharmacology and physiological actions of 5-HT in modifying blood pressure are important, given its involvement in circulatory shock, orthostatic hypotension, serotonin syndrome and hypertension. PMID:22407614

Review article: the many potential roles of intestinal serotonin (5-hydroxytryptamine, 5-HT) signalling in inflammatory bowel disease.

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Coates, M D; Tekin, I; Vrana, K E; Mawe, G M

2017-09-01

Serotonin (5-hydroxytryptamine, 5-HT) is an important mediator of every major gut-related function. Recent investigations also suggest that 5-HT can influence the development and severity of inflammation within the gut, particularly in the setting of inflammatory bowel disease (IBD). To review the roles that the intestinal serotonin signalling system plays in gut function, with a specific focus on IBD. We reviewed manuscripts from 1952 to 2017 that investigated and discussed roles for 5-HT signalling in gastrointestinal function and IBD, as well as the influence of inflammation on 5-HT signalling elements within the gut. Inflammation appears to affect every major element of intestinal 5-HT signalling, including 5-HT synthesis, release, receptor expression and reuptake capacity. Importantly, many studies (most utilising animal models) also demonstrate that modulation of selective serotonergic receptors (via agonism of 5-HT 4 R and antagonism of 5-HT 3 R) or 5-HT signal termination (via serotonin reuptake inhibitors) can alter the likelihood and severity of intestinal inflammation and/or its complicating symptoms. However, there are few human studies that have studied these relationships in a targeted manner. Insights discussed in this review have strong potential to lead to new diagnostic and therapeutic tools to improve the management of IBD and other related disorders. Specifically, strategies that focus on modifying the activity of selective serotonin receptors and reuptake transporters in the gut could be effective for controlling disease activity and/or its associated symptoms. Further studies in humans are required, however, to more completely understand the pathophysiological mechanisms underlying the roles of 5-HT in this setting. © 2017 John Wiley & Sons Ltd.

Serotonin and brain function: a tale of two receptors.

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Carhart-Harris, R L; Nutt, D J

2017-09-01

Previous attempts to identify a unified theory of brain serotonin function have largely failed to achieve consensus. In this present synthesis, we integrate previous perspectives with new and older data to create a novel bipartite model centred on the view that serotonin neurotransmission enhances two distinct adaptive responses to adversity, mediated in large part by its two most prevalent and researched brain receptors: the 5-HT1A and 5-HT2A receptors. We propose that passive coping (i.e. tolerating a source of stress) is mediated by postsynaptic 5-HT1AR signalling and characterised by stress moderation. Conversely, we argue that active coping (i.e. actively addressing a source of stress) is mediated by 5-HT2AR signalling and characterised by enhanced plasticity (defined as capacity for change). We propose that 5-HT1AR-mediated stress moderation may be the brain's default response to adversity but that an improved ability to change one's situation and/or relationship to it via 5-HT2AR-mediated plasticity may also be important - and increasingly so as the level of adversity reaches a critical point. We propose that the 5-HT1AR pathway is enhanced by conventional 5-HT reuptake blocking antidepressants such as the selective serotonin reuptake inhibitors (SSRIs), whereas the 5-HT2AR pathway is enhanced by 5-HT2AR-agonist psychedelics. This bipartite model purports to explain how different drugs (SSRIs and psychedelics) that modulate the serotonergic system in different ways, can achieve complementary adaptive and potentially therapeutic outcomes.

Transient Serotonin Syndrome by Concurrent Use of Electroconvulsive Therapy and Selective Serotonin Reuptake Inhibitor: A Case Report and Review of the Literature

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Nagahisa Okamoto

2012-01-01

Full Text Available The serotonin syndrome, which is characterized by psychiatric, autonomic nervous and neurological symptoms, is considered to be caused by excessive stimulation of the 5-HT1A and 5-HT2 receptors in the gray matter and spinal cord of the central nervous system, after the start of dosing or increase of the dose of a serotoninergic drug. There have been hardly any reports of induction of serotonin syndrome by electroconvulsive therapy (ECT in combination with antidepressant. We present the case of a female patient with major depressive disorder (MDD who developed transient serotonin syndrome soon after the first session of ECT in combination with paroxetine. Paroxetine was discontinued, and her psychiatric, autonomic nervous and neurological symptoms were gradually relieved and disappeared within 2 days. We performed the second ECT session 5 days after the initial session and performed 12 sessions of ECT without any changes in the procedure of ECT and anesthesia, but no symptoms of SS were observed. Finally, her MDD remitted. ECT might cause transiently increased blood-brain barrier (BBB permeability and enhance the transmissivity of the antidepressant in BBB. Therefore, it is necessary to pay attention to rare side effect of serotonin syndrome by ECT in combination with antidepressant.

Transient serotonin syndrome by concurrent use of electroconvulsive therapy and selective serotonin reuptake inhibitor: a case report and review of the literature.

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Okamoto, Nagahisa; Sakamoto, Kota; Yamada, Maki

2012-01-01

The serotonin syndrome, which is characterized by psychiatric, autonomic nervous and neurological symptoms, is considered to be caused by excessive stimulation of the 5-HT1A and 5-HT2 receptors in the gray matter and spinal cord of the central nervous system, after the start of dosing or increase of the dose of a serotoninergic drug. There have been hardly any reports of induction of serotonin syndrome by electroconvulsive therapy (ECT) in combination with antidepressant. We present the case of a female patient with major depressive disorder (MDD) who developed transient serotonin syndrome soon after the first session of ECT in combination with paroxetine. Paroxetine was discontinued, and her psychiatric, autonomic nervous and neurological symptoms were gradually relieved and disappeared within 2 days. We performed the second ECT session 5 days after the initial session and performed 12 sessions of ECT without any changes in the procedure of ECT and anesthesia, but no symptoms of SS were observed. Finally, her MDD remitted. ECT might cause transiently increased blood-brain barrier (BBB) permeability and enhance the transmissivity of the antidepressant in BBB. Therefore, it is necessary to pay attention to rare side effect of serotonin syndrome by ECT in combination with antidepressant.

Boosting serotonin in the brain: is it time to revamp the treatment of depression?

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Torrente, Mariana P; Gelenberg, Alan J; Vrana, Kent E

2012-05-01

Abnormalities in serotonin systems are presumably linked to various psychiatric disorders including schizophrenia and depression. Medications intended for these disorders aim to either block the reuptake or the degradation of this neurotransmitter. In an alternative approach, efforts have been made to enhance serotonin levels through dietary manipulation of precursor levels with modest clinical success. In the last 30 years, there has been little improvement in the pharmaceutical management of depression, and now is the time to revisit therapeutic strategies for the treatment of this disease. Tryptophan hydroxylase (TPH) catalyzes the first and rate-limiting step in the biosynthesis of serotonin. A recently discovered isoform, TPH2, is responsible for serotonin biosynthesis in the brain. Learning how to activate this enzyme (and its polymorphic versions) may lead to a new, more selective generation of antidepressants, able to regulate the levels of serotonin in the brain with fewer side effects.

Serotonin control of thermotaxis memory behavior in nematode Caenorhabditis elegans.

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Li, Yinxia; Zhao, Yunli; Huang, Xu; Lin, Xingfeng; Guo, Yuling; Wang, Daoyong; Li, Chaojun; Wang, Dayong

2013-01-01

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.

Effects of calcium antagonists on isolated bovine cerebral arteries: inhibition of constriction and calcium-45 uptake induced by potassium or serotonin

International Nuclear Information System (INIS)

Wendling, W.W.; Harakal, C.

1987-01-01

The purpose of this study was to determine the mechanisms by which organic calcium channel blockers inhibit cerebral vasoconstriction. Isolated bovine middle cerebral arteries were cut into rings to measure contractility or into strips to measure radioactive calcium ( 45 Ca) influx and efflux. Calcium channel blockers (10(-5) M verapamil or 3.3 X 10(-7) M nifedipine) and calcium-deficient solutions all produced near-maximal inhibition of both potassium- and serotonin-induced constriction. In calcium-deficient solutions containing potassium or serotonin, verapamil and nifedipine each blocked subsequent calcium-induced constriction in a competitive manner. Potassium and serotonin significantly increased 45 Ca uptake into cerebral artery strips during 5 minutes of 45 Ca loading; for potassium 45 Ca uptake increased from 62 to 188 nmol/g, and for serotonin from 65 to 102 nmol/g. Verapamil or nifedipine had no effect on basal 45 Ca uptake but significantly blocked the increase in 45 Ca uptake induced by potassium or serotonin. Potassium, and to a lesser extent serotonin, each induced a brief increase in the rate of 45 Ca efflux into calcium-deficient solutions. Verapamil or nifedipine had no effect on basal or potassium-stimulated 45 Ca efflux. The results demonstrate that verapamil and nifedipine block 45 Ca uptake through both potential-operated (potassium) and receptor-operated (serotonin) channels in bovine middle cerebral arteries

Characterization of bromine-76-labelled 5-bromo-6-nitroquipazine for PET studies of the serotonin transporter

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Lundkvist, Camilla E-mail: Lundkvis@shfj.cea.fr; Loc' h, Christian; Halldin, Christer; Bottlaender, Michel; Ottaviani, Michele; Coulon, Christine; Fuseau, Chantal; Mathis, Chester; Farde, Lars; Maziere, Bernard

1999-07-01

The development of suitable radioligands for brain imaging of the serotonin transporter is of great importance for the study of depression and other affective disorders. The potent and selective serotonin transporter ligand, 5-iodo-6-nitro-2-piperazinylquinoline, has been labelled with iodine-123 and used as a radioligand for single photon emission computerized tomography. To evaluate the potential of the bromine-76-labelled analogue, 5-bromo-6-nitroquipazine, as a radioligand for positron emission tomography (PET), its brain distribution and binding characteristics were examined in rats. In vivo brain distribution and ex vivo autoradiography demonstrated that [{sup 76}Br]5-bromo-6-nitroquipazine enters the brain rapidly. The regional brain distribution of [{sup 76}Br]5-bromo-6-nitroquipazine was consistent with the known distribution of serotonin transporters in the midbrain, pons, thalamus, striatum, and neocortex. Specific binding was inhibited by the selective serotonin reuptake inhibitor citalopram. The peripheral metabolism in plasma was rapid, but more than 90% of the radioactivity in brain represented unchanged radioligand 2 h postinjection (p.i.). A preliminary PET study was also performed in a baboon. Following the intravenous injection of [{sup 76}Br]5-bromo-6-nitroquipazine in a baboon, there was a conspicuous accumulation of radioactivity in thalamus, striatum, and pons. The radioactivity in these brain regions was 1.5 times higher than in the cerebellum at 3 h and 2.5-4 times higher at 24 h. A rapid metabolism of the radioligand in plasma was observed (38% unchanged after 5 min). The results indicate that [{sup 76}Br]5-bromo-6-nitroquipazine has potential for PET imaging of the serotonin transporter.

Serotonin control of thermotaxis memory behavior in nematode Caenorhabditis elegans.

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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.

Serotonin Control of Thermotaxis Memory Behavior in Nematode Caenorhabditis elegans

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Guo, Yuling; Wang, Daoyong; Li, Chaojun; Wang, Dayong

2013-01-01

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. PMID:24223727

Preschool outcomes following prenatal serotonin reuptake inhibitor exposure: differences in language and behavior, but not cognitive function.

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Johnson, Katrina C; Smith, Alicia K; Stowe, Zachary N; Newport, D Jeffrey; Brennan, Patricia A

2016-02-01

To test the hypothesis that prenatal exposure to serotonin reuptake inhibitors (SRIs) is associated with language and behavioral outcomes in preschool-aged children, while accounting for confounds such as concomitant exposures and maternal mental illness. An observational, prospective, longitudinal study of mental illness in pregnancy was conducted at a university-based women's mental health clinic (April 2010-November 2012). A sample of 178 mother-child dyads participated in a laboratory visit at preschool age (2.5-5.5 years). The majority of women (87%) received psychotropic medication during pregnancy. Psychiatric status (based on DSM-IV), other medication use, and substance use were serially assessed and tested as confounds. Primary outcome measures included standardized measures of expressive language and cognitive function and mother and alternate caregiver ratings of child behavior problems, including the Pervasive Developmental Disorders (PDD) subscale of the Child Behavior Checklist. Linear regression analyses revealed that, after controlling for relevant covariates, expressive language scores from the Test of Early Language Development, 3rd edition, were negatively associated with prenatal SRI exposure (β = -0.15, t = -2.41), while the PDD behavioral problems subscales completed by alternate caregivers and mothers were positively associated with prenatal SRI exposure (β = 0.17, t = 2.01; β = 0.16, t = 2.00, respectively). Cognitive function, measured using the Differential Ability Scales, 2nd edition, was not associated with any medication exposures. The current data suggest a small but significant association between prenatal SRI exposure and preschool outcomes, including expressive language and behavior problems. These data corroborate data from recent, population-based studies, although overall, published findings are mixed. Replication and identification of moderating risk factors are needed to understand potential clinical implications. �

Synthesis and serotonin transporter activity of sulphur-substituted alpha-alkyl phenethylamines as a new class of anticancer agents

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Cloonan, Suzanne M.; Keating, John J.; Butler, Stephen G.

2009-01-01

The discovery that some serotonin reuptake transporter (SERT) ligands have the potential to act as pro-apoptotic agents in the treatment of cancer adds greatly to their diverse pharmacological application. 4-Methylthioamphetamine (MTA) is a selective ligand for SERT over other monoamine...

Glioblastoma chemotherapy adjunct via potent serotonin receptor-7 inhibition using currently marketed high-affinity antipsychotic medicines

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Kast, RE

2010-01-01

Glioblastoma treatment as now constituted offers increased survival measured in months over untreated patients. Because glioblastomas are active in synthesizing a bewildering variety of growth factors, a systematic approach to inhibiting these is being undertaken as treatment adjunct. The serotonin 7 receptor is commonly overexpressed in glioblastoma. Research documentation showing agonists at serotonin receptor 7 cause increased extracellular regulated kinase 1/2 activation, increased interleukin-6 synthesis, increased signal transducer and activator of transcription-3 activation, increased resistance to apoptosis and other growth enhancing changes in glioblastoma is reviewed in this paper. Because three drugs in wide use to treat thought disorders – paliperidone, pimozide and risperidone – are also potent and well-tolerated inhibitors at serotonin receptor 7, these drugs should be studied for growth factor deprivation in an adjunctive role in glioblastoma treatment. PMID:20880389

Dextromethorphan, chlorphenamine and serotonin toxicity: case report and systematic literature review

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Monte, Andrew A; Chuang, Ryan; Bodmer, Michael

2010-01-01

The aim of this review was to describe a patient with serotonin toxicity after an overdose of dextromethorphan and chlorphenamine and to perform a systematic literature review exploring whether dextromethorphan and chlorphenamine may be equally contributory in the development of serotonin toxicity in overdose. A Medline literature review was undertaken to identify cases of serotonin toxicity due to dextromethorphan and/or chlorphenamine. Case reports were included if they included information on the ingested dose or plasma concentrations of dextromethorphan and/or chlorphenamine, information about co-ingestions and detailed clinical information to evaluate for serotonin toxicity. Cases were reviewed by two toxicologists and serotonin toxicity, defined by the Hunter criteria, was diagnosed when appropriate. The literature was then reviewed to evaluate whether chlorphenamine may be a serotonergic agent. One hundred and fifty-five articles of dextromethorphan or chlorphenamine poisoning were identified. There were 23 case reports of dextromethorphan, of which 18 were excluded for lack of serotonin toxicity. No cases were identified in which serotonin toxicity could be solely attributed to chlorphenamine. This left six cases of dextrometorphane and/or chlorphenamine overdose, including our own, in which serotonin toxicity could be diagnosed based on the presented clinical information. In three of the six eligible cases dextromethorphan and chlorphenamine were the only overdosed drugs. There is substantial evidence from the literature that chlorphenamine is a similarly potent serotonin re-uptake inhibitor when compared with dextrometorphan. Chlorphenamine is a serotonergic medication and combinations of chlorphenamine and dextromethorphan may be dangerous in overdose due to an increased risk of serotonin toxicity. PMID:21175434

Molecular cloning, expression and characterization of a bovine serotonin transporter

DEFF Research Database (Denmark)

Mortensen, O V; Kristensen, A S; Rudnick, G

1999-01-01

The serotonin transporter (SERT) is a member of a highly homologous family of sodium/chloride dependent neurotransmitter transporters responsible for reuptake of biogenic amines from the extracellular fluid. SERT constitutes the pharmacological target of several clinically important antidepressan......-methylenedioxymethamphetamine (MDMA) was mainly unchanged. RT-PCR amplification of RNA from different tissues demonstrated expression of SERT in placenta, brain stem, bone marrow, kidney, lung, heart, adrenal gland, liver, parathyroid gland, thyroid gland, small intestine and pancreas....

Cellular correlates of enhanced anxiety caused by acute treatment with the selective serotonin reuptake inhibitor fluoxetine in rats

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Shilpa eRavinder

2011-12-01

Full Text Available Selective serotonin reuptake inhibitors (SSRIs are used extensively in the treatment of depression and anxiety disorders. The therapeutic benefits of SSRIs typically require several weeks of continuous treatment. Intriguingly, according to clinical reports, symptoms of anxiety may actually increase during the early stages of treatment although more prolonged treatment alleviates affective symptoms. Consistent with earlier studies that have used animal models to capture this paradoxical effect of SSRIs, we find that rats exhibit enhanced anxiety-like behavior on the elevated plus-maze one hour after a single injection of the SSRI fluoxetine. Next we investigated the potential neural substrates underlying the acute anxiogenic effects by analyzing the morphological and physiological impact of acute fluoxetine treatment on principal neurons of the basolateral amygdala (BLA, a brain area that plays a pivotal role in fear and anxiety. Although earlier studies have shown that behavioral or genetic perturbations that are anxiogenic for rodents also increase dendritic spine-density in the BLA, we find that a single injection of fluoxetine does not cause spinogenesis on proximal apical dendritic segments on BLA principal neurons an hour later. However, at the same time point when a single dose of fluoxetine caused enhanced anxiety, it also enhanced action potential firing in BLA neurons in ex vivo slices. Consistent with this finding, in vitro bath application of fluoxetine caused higher spiking frequency and this increase in excitability was correlated with an increase in the input resistance of these neurons. Our results suggest that enhanced excitability of amygdala neurons may contribute to the increase in anxiety-like behavior observed following acute fluoxetine treatment.

An association between initiation of selective serotonin reuptake inhibitors and suicide - a nationwide register-based case-crossover study.

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Charlotte Björkenstam

Full Text Available BACKGROUND: Treatment with selective serotonin reuptake inhibitors (SSRI is one of the most common treatments for depression. It is however not clear whether or not there is an increased short-term suicide risk during initiation with SSRI. METHODS: A register-based nationwide case-crossover study including 5,866 suicides, 1,698 women and 4,168 men, from the Death Register 2007-2010 in Sweden. SSRI initiation was defined as a dispensed prescription of SSRI within 28 days prior to the date of suicide with no previous dispensed prescription of SSRI within 4 months prior that prescription. The control period took place one year earlier. Odds ratio (OR was estimated using conditional logistic regression. RESULT: During the 28 day period prior to suicide 48 women and 138 men were exposed to SSRI initiation (while not being exposed in the control period and 22 women and 43 men were exposed in the control period (while not being exposed in the case period. The OR for suicide after initiation with SSRI was 2.7 (95% CI: 1.6-44 for women, and 4.3 (95% CI: 3.0-6.1 for men. The highest OR was found 8-11 days after initiation with SSRI 9.7 (95% CI: 3.0-31.7 for women and men combined. CONCLUSION: The main limitation in this study is confounding by indication, but the descriptive question is however not confounded by indication. Together with plausible biological mechanisms and previous clinical and epidemiological observations our findings, linking initiation of SSRI to increased short-term suicide risk, deserve further attention specifically in the clinical setting.

Aggravation by paroxetine, a selective serotonin reuptake inhibitor, of antral lesions generated by nonsteroidal anti-inflammatory drugs in rats.

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Takeuchi, Koji; Tanaka, Akiko; Nukui, Kazuo; Kojo, Azusa; Gyenge, Melinda; Amagase, Kikuko

2011-09-01

Recent clinical studies have suggested a risk of adverse gastric reactions from the concomitant use of selective serotonin (5-HT) reuptake inhibitors (SSRIs) with nonsteroidal anti-inflammatory drugs (NSAIDs). We examined the adverse effects of SSRIs on antral lesions produced by indomethacin in rats. Rats fasted for 24 h were refed for 1 h, then administered indomethacin (30 mg/kg s.c.) 1 h after the refeeding and killed 6 h later. Paroxetine (1-10 mg/kg) was given orally 30 min before indomethacin. Indomethacin caused antral lesions in refed rats. Paroxetine dose-dependently aggravated these lesions, despite provoking no damage by itself. Similar results were obtained when other NSAIDs such as diclofenac, flurbiprofen, and loxoprofen were coadministered with paroxetine or when indomethacin was coadministered with other antidepressants such as fluvoxamine and milnacipran, but not imipramine or maprotiline. Exogenous 5-HT also worsened the indomethacin-induced antral damage, whereas the aggravating effect of paroxetine was attenuated by ondansetron, a selective 5-HT(3) antagonist, but not antagonists for other 5-HT receptor subtypes. Indomethacin plus paroxetine had no effect on gastric secretion but significantly decreased mucosal superoxide dismutase (SOD) activity as well as GSH content. The antral damage induced by indomethacin plus paroxetine was significantly prevented by antisecretory (acid or pepsin) agents and mucosal protective agents as well as SOD and allopurinol. These results suggest that SSRIs aggravate NSAID-induced antral lesions, probably via the activation of 5HT(3) receptors, and the mechanism of aggravation may involve the corrosive action of acid/pepsin as well as an impaired antioxidative system.

Neuroendocrine disruption in the shore crab Carcinus maenas: Effects of serotonin and fluoxetine on chh- and mih-gene expression, glycaemia and ecdysteroid levels.

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Robert, Alexandrine; Monsinjon, Tiphaine; Delbecque, Jean-Paul; Olivier, Stéphanie; Poret, Agnès; Foll, Frank Le; Durand, Fabrice; Knigge, Thomas

2016-06-01

Serotonin, a highly conserved neurotransmitter, controls many biological functions in vertebrates, but also in invertebrates. Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine, are commonly used in human medication to ease depression by affecting serotonin levels. Their residues and metabolites can be detected in the aquatic environment and its biota. They may also alter serotonin levels in aquatic invertebrates, thereby perturbing physiological functions. To investigate whether such perturbations can indeed be expected, shore crabs (Carcinus maenas) were injected either with serotonin, fluoxetine or a combination of both. Dose-dependent effects of fluoxetine ranging from 250 to 750nM were investigated. Gene expression of crustacean hyperglycemic hormone (chh) as well as moult inhibiting hormone (mih) was assessed by RT-qPCR at 2h and 12h after injection. Glucose and ecdysteroid levels in the haemolymph were monitored in regular intervals until 12h. Serotonin led to a rapid increase of chh and mih expression. On the contrary, fluoxetine only affected chh and mih expression after several hours, but kept expression levels significantly elevated. Correspondingly, serotonin rapidly increased glycaemia, which returned to normal or below normal levels after 12h. Fluoxetine, however, resulted in a persistent low-level increase of glycaemia, notably during the period when negative feedback regulation reduced glycaemia in the serotonin treated animals. Ecdysteroid levels were significantly decreased by serotonin and fluoxetine, with the latter showing less pronounced and less rapid, but longer lasting effects. Impacts of fluoxetine on glycaemia and ecdysteroids were mostly observed at higher doses (500 and 750nM) and affected principally the response dynamics, but not the amplitude of glycaemia and ecdysteroid-levels. These results suggest that psychoactive drugs are able to disrupt neuroendocrine control in decapod crustaceans, as they interfere with the

Brain Serotonin Transporter Occupancy by Oral Sibutramine Dosed to Steady State: A PET Study Using 11C-DASB in Healthy Humans

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Talbot, Peter S; Bradley, Stefan; Clarke, Cyril P; Babalola, Kola O; Philipp, Andrew W; Brown, Gavin; McMahon, Adam W; Matthews, Julian C

2010-01-01

Sibutramine is a centrally acting monoamine reuptake inhibitor prescribed as an appetite suppressant in the management of obesity. Its effects are mostly attributable to serotonin and norepinephrine transporter (SERT and NET, respectively) inhibition by its potent metabolites mono-desmethylsibutramine (M1) and di-desmethylsibutramine (M2). However, there is a paucity of in vivo data in humans about mechanisms underlying both clinical efficacy and the dose-independent non-response observed in a minority of patients. Twelve healthy male patients (mean age 41 years) completed a double-blind, placebo-controlled, within-subject crossover investigation of brain SERT occupancy by sibutramine 15 mg daily at steady state. Correlations were measured between occupancy and (i) plasma concentrations of sibutramine, M1 and M2; (ii) appetite suppression. 11C-DASB PET scans were performed on the HRRT camera. Binding potentials (BPND) were calculated by the Logan reference tissue (cerebellum) method. SERT occupancy was modest (mean 30±10%), was similar across brain regions, but varied widely across subjects (15–46%). Occupancy was correlated positively (p=0.09) with M2 concentration, but not with sibutramine or M1. No significant appetite suppression was seen at sibutramine is of modest magnitude and may be mediated predominantly by M2 in humans. 5-HT reuptake inhibition may be necessary but is not sufficient for sibutramine's efficacy in humans, supporting preclinical data suggesting that the hypophagic effect requires the co-inhibition of both SERT and NET. PMID:19890256

Effects of selective serotonin reuptake inhibitor treatment on plasma oxytocin and cortisol in major depressive disorder.

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Keating, Charlotte; Dawood, Tye; Barton, David A; Lambert, Gavin W; Tilbrook, Alan J

2013-04-29

Oxytocin is known for its capacity to facilitate social bonding, reduce anxiety and for its actions on the stress hypothalamopituitary adrenal (HPA) axis. Since oxytocin can physiologically suppress activity of the HPA axis, clinical applications of this neuropeptide have been proposed in conditions where the function of the HPA axis is dysregulated. One such condition is major depressive disorder (MDD). Dysregulation of the HPA system is the most prominent endocrine change seen with MDD, and normalizing the HPA axis is one of the major targets of recent treatments. The potential clinical application of oxytocin in MDD requires improved understanding of its relationship to the symptoms and underlying pathophysiology of MDD. Previous research has investigated potential correlations between oxytocin and symptoms of MDD, including a link between oxytocin and treatment related symptom reduction. The outcomes of studies investigating whether antidepressive treatment (pharmacological and non-pharmacological) influences oxytocin concentrations in MDD, have produced conflicting outcomes. These outcomes suggest the need for an investigation of the influence of a single treatment class on oxytocin concentrations, to determine whether there is a relationship between oxytocin, the HPA axis (e.g., oxytocin and cortisol) and MDD. Our objective was to measure oxytocin and cortisol in patients with MDD before and following treatment with selective serotonin reuptake inhibitors, SSRI. We sampled blood from arterial plasma. Patients with MDD were studied at the same time twice; pre- and post- 12 weeks treatment, in an unblinded sequential design (clinicaltrials.govNCT00168493). Results did not reveal differences in oxytocin or cortisol concentrations before relative to following SSRI treatment, and there were no significant relationships between oxytocin and cortisol, or these two physiological variables and psychological symptom scores, before or after treatment. These outcomes

Treatment with selective serotonin reuptake inhibitors and mirtapazine results in differential brain activation by visual erotic stimuli in patients with major depressive disorder.

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Kim, Won; Jin, Bo-Ra; Yang, Wan-Seok; Lee, Kyuong-Uk; Juh, Ra-Hyung; Ahn, Kook-Jin; Chung, Yong-An; Chae, Jeong-Ho

2009-06-01

The objective of this study was to identify patterns of brain activation elicited by erotic visual stimuli in patients treated with either Selective Serotonin Reuptake Inhibitors (SSRIs) or mirtazipine. Nine middle-aged men with major depressive disorder treated with an SSRI and ten middle-aged men with major depressive disorder treated with mirtazapine completed the trial. Ten subjects with no psychiatric illness were included as a control group. We conducted functional brain magnetic resonance imaging (fMRI) while a film alternatively played erotic and non-erotic contents for 14 minutes and 9 seconds. The control group showed activation in the occipitotemporal area, anterior cingulate gyrus, insula, orbitofrontal cortex, and caudate nucleus. For subjects treated with SSRIs, the intensity of activity in these regions was much lower compared to the control group. Intensity of activation in the group treated with mirtazapine was less than the control group but grea-ter than those treated with SSRIs. Using subtraction analysis, the SSRI group showed significantly lower activation than the mirtazapine group in the anterior cingulate gyrus and the caudate nucleus. Our study suggests that the different rates of sexual side effects between the patients in the SSRI-treated group and the mirtazapine-treated group may be due to different effects on brain activation.

Modulation of Olfactory Bulb Network Activity by Serotonin: Synchronous Inhibition of Mitral Cells Mediated by Spatially Localized GABAergic Microcircuits

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Schmidt, Loren J.; Strowbridge, Ben W.

2014-01-01

Although inhibition has often been proposed as a central mechanism for coordinating activity in the olfactory system, relatively little is known about how activation of different inhibitory local circuit pathways can generate coincident inhibition of principal cells. We used serotonin (5-HT) as a pharmacological tool to induce spiking in ensembles…

Pharmacokinetics of paroxetine, a selective serotonin reuptake inhibitor, in Grey parrots (Psittacus erithacus erithacus): influence of pharmaceutical formulation and length of dosing.

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van Zeeland, Y R A; Schoemaker, N J; Haritova, A; Smit, J W; van Maarseveen, E M; Lumeij, J T; Fink-Gremmels, J

2013-02-01

Paroxetine, a selective serotonin reuptake inhibitor, may be beneficial in the treatment of behavioural disorders in pet birds. The lack of pharmacokinetic data and clinical trials currently limits the use of this drug in clinical avian practice. This paper evaluates the pharmacokinetic properties and potential side effects of single and repeated dosing of paroxetine in Grey parrots (Psittacus erithacus erithacus). Paroxetine pharmacokinetics were studied after single i.v. and single oral dosing, and after repeated oral administration during 1 month. Plasma paroxetine concentrations were determined by liquid chromatography-tandem mass spectrometry. No undesirable side effects were observed during the study. Pharmacokinetic analysis revealed a quick distribution and rapid elimination after i.v. administration. Oral administration of paroxetine HCl dissolved in water resulted in a relatively slow absorption (T(max)=5.9±2.6 h) and a low bioavailability (31±15%). Repeated administration resulted in higher rate of absorption, most likely due to a saturation of the cytochrome P450-mediated first-pass metabolism. This study shows that oral administration of paroxetine HCl (4 mg/kg twice daily) in parrots results in plasma concentrations within the therapeutic range recommended for the treatment of depressions in humans. Further studies are needed to demonstrate the clinical efficacy of this dosage regimen in parrots with behavioural disorders. © 2012 Blackwell Publishing Ltd.

Interplay between the key proteins of serotonin system in SSRI antidepressants efficacy.

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Kulikov, Alexander V; Gainetdinov, Raul R; Ponimaskin, Evgeni; Kalueff, Allan V; Naumenko, Vladimir S; Popova, Nina K

2018-04-01

Selective serotonin reuptake inhibitors (SSRIs) are the most effective and most used antidepressant drugs. Acting by inhibiting serotonin (5-HT) transporter, SSRIs display a typical 3-4-week delay in their therapeutic effects, with nearly 40% of depressed patients remaining treatment-resistant. Recent evidence suggests complex interplay between 5-HT receptors and key proteins of 5-HT metabolism in molecular mechanisms of such delay and resistance to SSRIs. Area covered: This paper concentrates on the interplay between 5-HT receptors in the delay of therapeutic effect of SSRIs, and the interaction between tryptophan hydroxylase 2 and 5-HT transporter in the SSRI resistance. Specifically, it discusses: (1) the data on the association between antidepressant drug efficacy and genetically defined characteristics of key proteins in the 5-HT signaling (TPH2, MAOA, SERT and 5-HT 1A receptor), (2) the effect of dimerization of 5-HT 7 and 5-HT 1A receptors on the internalization and functioning of 5-HT 1A presynaptic receptors, (3) the role of Tph2 deficiency in the resistance to SSRIs treatment. We shift the emphasis from individual proteins to their interactions in explaining antidepressant action of SSRI. Expert opinion: These interactions should be considered when developing more effective antidepressant drugs as well as for predicting and improving the efficacy of antidepressant therapies.

Association of the Polygenic Scores for Personality Traits and Response to Selective Serotonin Reuptake Inhibitors in Patients with Major Depressive Disorder

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Amare, Azmeraw T.; Schubert, Klaus Oliver; Tekola-Ayele, Fasil; Hsu, Yi-Hsiang; Sangkuhl, Katrin; Jenkins, Gregory; Whaley, Ryan M.; Barman, Poulami; Batzler, Anthony; Altman, Russ B.; Arolt, Volker; Brockmöller, Jürgen; Chen, Chia-Hui; Domschke, Katharina; Hall-Flavin, Daniel K.; Hong, Chen-Jee; Illi, Ari; Ji, Yuan; Kampman, Olli; Kinoshita, Toshihiko; Leinonen, Esa; Liou, Ying-Jay; Mushiroda, Taisei; Nonen, Shinpei; Skime, Michelle K.; Wang, Liewei; Kato, Masaki; Liu, Yu-Li; Praphanphoj, Verayuth; Stingl, Julia C.; Bobo, William V.; Tsai, Shih-Jen; Kubo, Michiaki; Klein, Teri E.; Weinshilboum, Richard M.; Biernacka, Joanna M.; Baune, Bernhard T.

2018-01-01

Studies reported a strong genetic correlation between the Big Five personality traits and major depressive disorder (MDD). Moreover, personality traits are thought to be associated with response to antidepressants treatment that might partly be mediated by genetic factors. In this study, we examined whether polygenic scores (PGSs) derived from the Big Five personality traits predict treatment response and remission in patients with MDD who were prescribed selective serotonin reuptake inhibitors (SSRIs). In addition, we performed meta-analyses of genome-wide association studies (GWASs) on these traits to identify genetic variants underpinning the cross-trait polygenic association. The PGS analysis was performed using data from two cohorts: the Pharmacogenomics Research Network Antidepressant Medication Pharmacogenomic Study (PGRN-AMPS, n = 529) and the International SSRI Pharmacogenomics Consortium (ISPC, n = 865). The cross-trait GWAS meta-analyses were conducted by combining GWAS summary statistics on SSRIs treatment outcome and on the personality traits. The results showed that the PGS for openness and neuroticism were associated with SSRIs treatment outcomes at p trait GWAS meta-analyses, we identified eight loci associated with (a) SSRIs response and conscientiousness near YEATS4 gene and (b) SSRI remission and neuroticism eight loci near PRAG1, MSRA, XKR6, ELAVL2, PLXNC1, PLEKHM1, and BRUNOL4 genes. An assessment of a polygenic load for personality traits may assist in conjunction with clinical data to predict whether MDD patients might respond favorably to SSRIs. PMID:29559929

Location of the Antidepressant Binding Site in the Serotonin Transporter IMPORTANCE OF SER-438 IN RECOGNITION OF CITALOPRAM AND TRICYCLIC ANTIDEPRESSANTS

DEFF Research Database (Denmark)

Andersen, Jacob; Taboureau, Olivier; Hansen, Kasper B.

2009-01-01

antidepressants, including the selective serotonin reuptake inhibitor citalopram and the tricyclic antidepressants imipramine, clomipramine, and amitriptyline. A conservative mutation of Ser-438 to threonine (S438T) selectively increased the K-i values for these antidepressants up to 175-fold. The effects...

Acute serotonin depletion releases motivated inhibition of response vigour

NARCIS (Netherlands)

Ouden, H.E.M. den; Swart, J.C.; Schmidt, K.; Fekkes, D.; Geurts, D.E.M.; Cools, R.

2015-01-01

Rationale The neurotransmitter serotonin has long been implicated in the motivational control of behaviour. Recent theories propose that the role of serotonin can be understood in terms of an interaction between a motivational and a behavioural activation axis. Experimental support for these ideas,

Acute serotonin depletion releases motivated inhibition of response vigour

NARCIS (Netherlands)

Ouden, H.E.M. den; Swart, J.C.; Schmidt, K.; Fekkes, D.; Geurts, D.E.M.; Cools, R.

2015-01-01

RATIONALE: The neurotransmitter serotonin has long been implicated in the motivational control of behaviour. Recent theories propose that the role of serotonin can be understood in terms of an interaction between a motivational and a behavioural activation axis. Experimental support for these ideas,

The serotonin transporter: Examination of the changes in transporter affinity induced by ligand binding

International Nuclear Information System (INIS)

Humphreys, C.J.

1989-01-01

The plasmalemmal serotonin transporter uses transmembrane gradients of Na + , Cl - and K + to accumulate serotonin within blood platelets. Transport is competitively inhibited by the antidepressant imipramine. Like serotonin transport, imipramine binding requires Na + . Unlike serotonin, however, imipramine does not appear to be transported. To gain insight into the mechanism of serotonin transport the author have analyzed the influences of Na + and Cl - , the two ions cotransported with serotonin, on both serotonin transport and the interaction of imipramine and other antidepressant drugs with the plasmalemmal serotonin transporter of human platelets. Additionally, the author have synthesized, purified and characterized the binding of 2-iodoimipramine to the serotonin transporter. Finally, the author have conducted a preliminary study of the inhibition of serotonin transport and imipramine binding produced by dicyclohexylcarbodiimide. My results reveal many instances of positive heterotropic cooperativity in ligand binding to the serotonin transporter. Na + binding enhances the transporters affinity for imipramine and several other antidepressant drugs, and also increases the affinity for Cl - . Cl - enhances the transporters affinity for imipramine, as well as for Na + . At concentrations in the range of its K M for transport serotonin is a competitive inhibitor of imipramine binding. At much higher concentrations, however, serotonin also inhibits imipramines dissociation rate constant. This latter effect which is Na + -independent and species specific, is apparently produced by serotonin binding at a second, low affinity site on, or near, the transporter complex. Iodoimipramine competitively inhibit both [ 3 H]imipramine binding and [ 3 H]serotonin transport

Prediction of response to paroxetine and venlafaxine by serotonin-related genes in obsessive-compulsive disorder in a randomized, double-blind trial

NARCIS (Netherlands)

Denys, Damiaan; van Nieuwerburgh, Filip; Deforce, Dieter; Westenberg, Herman G. M.

2007-01-01

OBJECTIVE: Serotonin reuptake inhibitors (SRIs) are the most effective pharmacologic treatment currently available for patients with obsessive-compulsive disorder (OCD). Still, up to 40% to 60% of OCD patients do not respond to SRI treatment. The purpose of the present study was to determine whether

Maternal Use of Selective Serotonin Reuptake Inhibitors and Lengthening of the Umbilical Cord: Indirect Evidence of Increased Foetal Activity-A Retrospective Cohort Study.

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Julia Kivistö

Full Text Available Antenatal depression affects up to 19% of pregnant women. Some of these women are also in need of antidepressant treatment. Nevertheless, the impact of maternal antidepressant treatment and prenatal depression on the course of pregnancy, foetal development and delivery outcomes is not fully understood.We analysed data from 24 818 women who gave birth at Kuopio University Hospital between 2002-2012. Logistic regression analysis was used to estimate associations between the use of selective serotonin reuptake inhibitors (SSRIs during pregnancy and the progression of pregnancy, development of the foetus and delivery outcomes.Altogether, 369 (1.5% women used SSRIs. A regression model adjusted for age, overweight, nulliparity, prior termination, miscarriages, smoking, maternal alcohol consumption, chronic illness and polyhydramnion showed that pregnant women exposed to SSRI medication had significantly lower Apgar scores at 1 minute (p < 0.0001 and 5 minutes (p < 0.0001 and more admissions to the neonatal intensive care unit (p < 0.0001 than unexposed pregnant women. In addition, exposed newborns had longer umbilical cords (p < 0.0001 than non-exposed newborns.In addition to the previously known associates with maternal SSRI exposure, such as lowered Apgar scores, SSRI exposure appeared to be associated with increased umbilical cord length. The observation related to increased umbilical cord length may be explained by an SSRI-induced increase in the movements of the developing foetus.

Effects of paroxetine-mediated inhibition of GRK2 expression on depression and cardiovascular function in patients with myocardial infarction

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Tian XQ

2016-09-01

Full Text Available Xiuqing Tian,1 Qing Wang,1 Rui Guo,2 Lingling Xu,3 Qin M Chen,4 Yinglong Hou1 1Department of Cardiology, Qianfoshan Hospital of Shandong University, Jinan City, 2Department of Physiology, Nanjing University of Chinese Medicine, Nanjing City, 3College of Medicine, Weifang Medical University, Weifang City, People’s Republic of China; 4Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, USA Background: Paroxetine is a selective serotonin reuptake inhibitor utilized in the treatment of depression and anxiety disorders. Recent studies have identified paroxetine as a G protein-coupled receptor kinase-2 (GRK2 inhibitor capable of reversing cardiac dysfunction and remodeling in experimental models of acute myocardial infarction (AMI. We determine the clinical importance of paroxetine on cardiac functions in patients having AMI with depression (AMID in comparison with fluoxetine, an unrelated selective serotonin reuptake inhibitor that does not inhibit GRK2.Methods: Diagnosis of depression was based on the 17-item Hamilton Depression Scale and Self-rating Depression Scale in AMI patients after hospital admission. AMID patients were randomly assigned to paroxetine or fluoxetine for treatment of depression. Heart rate variability and cardiac function were evaluated. GRK2 protein levels were measured using peripheral lymphocytes and Western blot.Results: GRK2 expression in AMID patients was significantly higher than that in AMI patients without depression. In AMID patients, GRK2 levels were positively correlated with the 17-item Hamilton Depression Scale and the Self-rating Depression Scale scores, and negatively correlated with heart rate variability. Treatment of AMID patients with paroxetine significantly reduced the expression of GRK2, normalized the autonomic nervous system function, and improved cardiac performance. In contrast, fluoxetine normalized the autonomic nervous system but did not reduce the expression of

R-citalopram inhibits functional and 5-HTP-evoked behavioural responses to the SSRI, escitalopram

DEFF Research Database (Denmark)

Sanchez, C; Kreilgaard, Mads

2004-01-01

Escitalopram mediates the serotonin re-uptake inhibitory and antidepressant effect of citalopram racemate. However, recent studies have shown that R-citalopram inhibits the escitalopram-induced increase of extracellular 5-HT levels in the frontal cortex of rats. Here, we investigated the inhibitory...... effect of R-citalopram on the escitalopram-induced increase of 5-HT neurotransmission at the behavioural [potentiation of 5-hydroxytryptophan (5-HTP)-induced behavioural changes in mice and rats] and functional (increase in serum corticosterone in rats) levels. The effect of escitalopram was inhibited...... by R-citalopram in all three models, and R-citalopram, given alone, was inactive. The effects were more pronounced using an escitalopram to R-citalopram ratio of 1:4 than ratios of 1:2 and 1:1, suggesting a dose-dependent effect. The ED(50)-value of escitalopram in mouse 5-HTP potentiation studies...

High familial risk for mood disorder is associated with low dorsolateral prefrontal cortex serotonin transporter binding

DEFF Research Database (Denmark)

Frokjaer, Vibe G; Vinberg, Maj; Erritzoe, David

2009-01-01

at risk for developing depression. The aim of this study was to explore whether abnormalities in SERT might be present in healthy individuals with familial predisposition to mood disorder. Nine individuals at high familial risk (mean age 32.2+/-4.2 years) and 11 individuals at low risk (mean age 32......Mood disorders are elicited through a combination of genetic and environmental stress factors, and treatment with selective serotonin reuptake inhibitors ameliorates depressive symptoms. Changes in the serotonin transporter (SERT) binding may therefore occur in depressive patients and in subjects.......4+/-5.0 years) for developing mood disorder were included. The subjects were healthy twins with or without a co-twin history of mood disorder identified by linking information from the Danish Twin Register and the Danish Psychiatric Central Register. Regional in vivo brain serotonin transporter binding...

Serotonin selectively influences moral judgment and behavior through effects on harm aversion.

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Crockett, Molly J; Clark, Luke; Hauser, Marc D; Robbins, Trevor W

2010-10-05

Aversive emotional reactions to real or imagined social harms infuse moral judgment and motivate prosocial behavior. Here, we show that the neurotransmitter serotonin directly alters both moral judgment and behavior through increasing subjects' aversion to personally harming others. We enhanced serotonin in healthy volunteers with citalopram (a selective serotonin reuptake inhibitor) and contrasted its effects with both a pharmacological control treatment and a placebo on tests of moral judgment and behavior. We measured the drugs' effects on moral judgment in a set of moral 'dilemmas' pitting utilitarian outcomes (e.g., saving five lives) against highly aversive harmful actions (e.g., killing an innocent person). Enhancing serotonin made subjects more likely to judge harmful actions as forbidden, but only in cases where harms were emotionally salient. This harm-avoidant bias after citalopram was also evident in behavior during the ultimatum game, in which subjects decide to accept or reject fair or unfair monetary offers from another player. Rejecting unfair offers enforces a fairness norm but also harms the other player financially. Enhancing serotonin made subjects less likely to reject unfair offers. Furthermore, the prosocial effects of citalopram varied as a function of trait empathy. Individuals high in trait empathy showed stronger effects of citalopram on moral judgment and behavior than individuals low in trait empathy. Together, these findings provide unique evidence that serotonin could promote prosocial behavior by enhancing harm aversion, a prosocial sentiment that directly affects both moral judgment and moral behavior.

Divergent Roles of Central Serotonin in Adult Hippocampal Neurogenesis

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Ning-Ning Song

2017-06-01

Full Text Available The central serotonin (5-HT system is the main target of selective serotonin reuptake inhibitors (SSRIs, the first-line antidepressants widely used in current general practice. One of the prominent features of chronic SSRI treatment in rodents is the enhanced adult neurogenesis in the hippocampus, which has been proposed to contribute to antidepressant effects. Therefore, tremendous effort has been made to decipher how central 5-HT regulates adult hippocampal neurogenesis. In this paper, we review how changes in the central serotonergic system alter adult hippocampal neurogenesis. We focus on data obtained from three categories of genetically engineered mouse models: (1 mice with altered central 5-HT levels from embryonic stages, (2 mice with deletion of 5-HT receptors from embryonic stages, and (3 mice with altered central 5-HT system exclusively in adulthood. These recent findings provide unique insights to interpret the multifaceted roles of central 5-HT on adult hippocampal neurogenesis and its associated effects on depression.

Differential interaction with the serotonin system by S-ketamine, vortioxetine, and fluoxetine in a genetic rat model of depression.

Science.gov (United States)

du Jardin, Kristian Gaarn; Liebenberg, Nico; Müller, Heidi Kaastrup; Elfving, Betina; Sanchez, Connie; Wegener, Gregers

2016-07-01

The mechanisms mediating ketamine's antidepressant effect have only been partly resolved. Recent preclinical reports implicate serotonin (5-hydroxytryptamine; 5-HT) in the antidepressant-like action of ketamine. Vortioxetine is a multimodal-acting antidepressant that is hypothesized to exert its therapeutic activity through 5-HT reuptake inhibition and modulation of several 5-HT receptors. The objective of this study was to evaluate the therapeutic-like profiles of S-ketamine, vortioxetine, and the serotonin reuptake inhibitor fluoxetine in response to manipulation of 5-HT tone. Flinders Sensitive Line (FSL) rats, a genetic model of depression, were depleted of 5-HT by repeated administration of 4-chloro-DL-phenylalanine methyl ester HCl (pCPA). Using pCPA-pretreated and control FSL rats, we investigated the acute and sustained effects of S-ketamine (15 mg/kg), fluoxetine (10 mg/kg), or vortioxetine (10 mg/kg) on recognition memory and depression-like behavior in the object recognition task (ORT) and forced swim test (FST), respectively. The behavioral phenotype of FSL rats was unaffected by 5-HT depletion. Vortioxetine, but not fluoxetine or S-ketamine, acutely ameliorated the memory deficits of FSL rats in the ORT irrespective of 5-HT tone. No sustained effects were observed in the ORT. In the FST, all three drugs demonstrated acute antidepressant-like activity but only S-ketamine had sustained effects. Unlike vortioxetine, the antidepressant-like responses of fluoxetine and S-ketamine were abolished by 5-HT depletion. These observations suggest that the acute and sustained antidepressant-like effects of S-ketamine depend on endogenous stimulation of 5-HT receptors. In contrast, the acute therapeutic-like effects of vortioxetine on memory and depression-like behavior may be mediated by direct activity at 5-HT receptors.

Antidepressants in the treatment of neuropathic pain

DEFF Research Database (Denmark)

Sindrup, Søren H.; Otto, Marit; Finnerup, Nanna Brix

2005-01-01

Neuropathic pain is due to lesion or dysfunction of the peripheral or central nervous system. Tricyclic antidepressants and anticonvulsants have long been the mainstay of treatment of this type of pain. Tricyclic antidepressants may relieve neuropathic pain by their unique ability to inhibit...... presynaptic reuptake of the biogenic amines serotonin and noradrenaline, but other mechanisms such as N-methyl-D-aspartate receptor and ion channel blockade probably also play a role in their pain-relieving effect. The effect of tricyclic antidepressants in neuropathic pain in man has been demonstrated...... in numerous randomised, controlled trials, and a few trials have shown that serotonin noradrenaline and selective serotonin reuptake inhibitor antidepressants also relieve neuropathic pain although with lower efficacy. Tricyclic antidepressants will relieve one in every 2-3 patients with peripheral...

Improved preclinical cardiovascular therapeutic indices with long-term inhibition of norepinephrine reuptake using reboxetine

NARCIS (Netherlands)

Fossa, Anthony A.; Wisialowski, Todd A.; Cremers, Thomas; van der Hart, Marieke; Tseng, Elaine; Deng, Shibing; Rollema, Hans; Wang, Ellen Q.

2012-01-01

Norepinephrine reuptake inhibitors (NRIs) acutely increase norepinephrine (NE) levels, but therapeutic antidepressant activity is only observed after weeks of treatment because central NE levels progressively increase during continued drug exposure. Similarly, while NRIs acutely increase blood

Investigation of the mechanisms underlying the hypophagic effects of the 5-HT and noradrenaline reuptake inhibitor, sibutramine, in the rat

Science.gov (United States)

Jackson, Helen C; Bearham, M Clair; Hutchins, Lisa J; Mazurkiewicz, Sarah E; Needham, Andrew M; Heal, David J

1997-01-01

Sibutramine is a novel 5-hydroxytryptamine (5-HT) and noradrenaline reuptake inhibitor (serotonin- noradrenaline reuptake inhibitor, SNRI) which is currently being developed as a treatment for obesity. Sibutramine has been shown to decrease food intake in the rat. In this study we have used a variety of monoamine receptor antagonists to examine the pharmacological mechanisms underlying sibutramine-induced hypophagia. Individually-housed male Sprague-Dawley rats were maintained on reversed phase lighting with free access to food and water. Drugs were administered at 09 h 00 min and food intake was monitored over the following 8 h dark period. Sibutramine (10 mg kg−1, p.o.) produced a significant decrease in food intake during the 8 h following drug administration. This hypophagic response was fully antagonized by the α1-adrenoceptor antagonist, prazosin (0.3 and 1 mg kg−1, i.p.), and partially antagonized by the β1-adrenoceptor antagonist, metoprolol (3 and 10 mg kg−1, i.p.) and the 5-HT receptor antagonists, metergoline (non-selective; 0.3 mg kg−1, i.p.); ritanserin (5-HT2A/2C; 0.1 and 0.5 mg kg−1, i.p.) and SB200646 (5-HT2B/2C; 20 and 40 mg kg−1, p.o.). By contrast, the α2-adrenoceptor antagonist, RX821002 (0.3 and 1 mg kg−1, i.p.) and the β2-adrenoceptor antagonist, ICI 118,551 (3 and 10 mg kg−1, i.p.) did not reduce the decrease in food intake induced by sibutramine. These results demonstrate that β1-adrenoceptors, 5-HT2A/2C-receptors and particularly α1-adrenoceptors, are involved in the effects of sibutramine on food intake and are consistent with the hypothesis that sibutramine-induced hypophagia is related to its ability to inhibit the reuptake of both noradrenaline and 5-HT, with the subsequent activation of a variety of noradrenaline and 5-HT receptor systems. PMID:9283694

A novel serotonin transporter ligand: (5-Iodo-2-(2-dimethylaminomethylphenoxy)-benzyl alcohol

Energy Technology Data Exchange (ETDEWEB)

Zhuang, Z.-P.; Choi, S.-R.; Hou, Catherine; Mu Mu; Kung, M.-P. E-mail: kunghf@sunmac.spect.upenn.edu; Acton, Paul D.; Kung, Hank F

2000-02-01

The serotonin transporters (SERT) are the primary binding sites for selective serotonin reuptake inhibitors, commonly used antidepressants such as fluoxetine, sertraline, and paroxetine. Imaging of SERT with positron emission tomography and single photon emission computed tomography in humans would provide a useful tool for understanding how alterations of this system are related to depressive illnesses and other psychiatric disorders. In this article the synthesis and characterization of [{sup 125}I]ODAM [(5-iodo-2-(2-dimethylaminomethylphenoxy)-benzyl alcohol, 9)] as an imaging agent in the evaluation of central nervous system SERT are reported. A new reaction scheme was developed for the preparation of compound 9, ODAM, and the corresponding tri-n-butyltin derivative 10. Upon reacting 10 with hydrogen peroxide and sodium[{sup 125}I]iodide, the radiolabeled [{sup 125}I]9 was obtained in good yield (94% yield, radiochemical purity >95%). In an initial binding study using cortical membrane homogenates of rat brain, ODAM displayed a good binding affinity with a value of K{sub i}=2.8{+-}0.88 nM. Using LLC-PK{sub 1} cells specifically expressing the individual transporter (i.e. dopamine [DAT], norepinephrine [NET], and SERT, respectively), ODAM showed a strong inhibition on SERT (K{sub i}=0.12{+-}0.02 nM). Inhibition constants for the other two transporters were lower (K{sub i}=3.9{+-}0.7 {mu}M and 20.0 {+-} 1.9 nM for DAT and NET, respectively). Initial biodistribution study in rats after an intravenous (IV) injection of [{sup 125}I]ODAM showed a rapid brain uptake and washout (2.03, 1.49, 0.79, 0.27, and 0.07% dose/organ at 2, 30, 60, 120, and 240 min, respectively). The hypothalamus region where the serotonin neurons are located exhibited a high specific uptake. Ratios of hypothalamus-cerebellum/cerebellum based on percent dose per gram of these two regions showed values of 0.35, 0.86, 0.86, 0.63, and 0.34 at 2, 30, 60, 120, and 240 min, post-IV injection

A novel serotonin transporter ligand: (5-Iodo-2-(2-dimethylaminomethylphenoxy)-benzyl alcohol

International Nuclear Information System (INIS)

Zhuang, Z.-P.; Choi, S.-R.; Hou, Catherine; Mu Mu; Kung, M.-P.; Acton, Paul D.; Kung, Hank F.

2000-01-01

The serotonin transporters (SERT) are the primary binding sites for selective serotonin reuptake inhibitors, commonly used antidepressants such as fluoxetine, sertraline, and paroxetine. Imaging of SERT with positron emission tomography and single photon emission computed tomography in humans would provide a useful tool for understanding how alterations of this system are related to depressive illnesses and other psychiatric disorders. In this article the synthesis and characterization of [ 125 I]ODAM [(5-iodo-2-(2-dimethylaminomethylphenoxy)-benzyl alcohol, 9)] as an imaging agent in the evaluation of central nervous system SERT are reported. A new reaction scheme was developed for the preparation of compound 9, ODAM, and the corresponding tri-n-butyltin derivative 10. Upon reacting 10 with hydrogen peroxide and sodium[ 125 I]iodide, the radiolabeled [ 125 I]9 was obtained in good yield (94% yield, radiochemical purity >95%). In an initial binding study using cortical membrane homogenates of rat brain, ODAM displayed a good binding affinity with a value of K i =2.8±0.88 nM. Using LLC-PK 1 cells specifically expressing the individual transporter (i.e. dopamine [DAT], norepinephrine [NET], and SERT, respectively), ODAM showed a strong inhibition on SERT (K i =0.12±0.02 nM). Inhibition constants for the other two transporters were lower (K i =3.9±0.7 μM and 20.0 ± 1.9 nM for DAT and NET, respectively). Initial biodistribution study in rats after an intravenous (IV) injection of [ 125 I]ODAM showed a rapid brain uptake and washout (2.03, 1.49, 0.79, 0.27, and 0.07% dose/organ at 2, 30, 60, 120, and 240 min, respectively). The hypothalamus region where the serotonin neurons are located exhibited a high specific uptake. Ratios of hypothalamus-cerebellum/cerebellum based on percent dose per gram of these two regions showed values of 0.35, 0.86, 0.86, 0.63, and 0.34 at 2, 30, 60, 120, and 240 min, post-IV injection, respectively. The specific uptake in hypothalamus

Association of the Polygenic Scores for Personality Traits and Response to Selective Serotonin Reuptake Inhibitors in Patients with Major Depressive Disorder

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Azmeraw T. Amare

2018-03-01

Full Text Available Studies reported a strong genetic correlation between the Big Five personality traits and major depressive disorder (MDD. Moreover, personality traits are thought to be associated with response to antidepressants treatment that might partly be mediated by genetic factors. In this study, we examined whether polygenic scores (PGSs derived from the Big Five personality traits predict treatment response and remission in patients with MDD who were prescribed selective serotonin reuptake inhibitors (SSRIs. In addition, we performed meta-analyses of genome-wide association studies (GWASs on these traits to identify genetic variants underpinning the cross-trait polygenic association. The PGS analysis was performed using data from two cohorts: the Pharmacogenomics Research Network Antidepressant Medication Pharmacogenomic Study (PGRN-AMPS, n = 529 and the International SSRI Pharmacogenomics Consortium (ISPC, n = 865. The cross-trait GWAS meta-analyses were conducted by combining GWAS summary statistics on SSRIs treatment outcome and on the personality traits. The results showed that the PGS for openness and neuroticism were associated with SSRIs treatment outcomes at p < 0.05 across PT thresholds in both cohorts. A significant association was also found between the PGS for conscientiousness and SSRIs treatment response in the PGRN-AMPS sample. In the cross-trait GWAS meta-analyses, we identified eight loci associated with (a SSRIs response and conscientiousness near YEATS4 gene and (b SSRI remission and neuroticism eight loci near PRAG1, MSRA, XKR6, ELAVL2, PLXNC1, PLEKHM1, and BRUNOL4 genes. An assessment of a polygenic load for personality traits may assist in conjunction with clinical data to predict whether MDD patients might respond favorably to SSRIs.

Serotonin receptor, SERT mRNA and correlations with symptoms in males with alcohol dependence and suicide.

Science.gov (United States)

Thompson, P M; Cruz, D A; Olukotun, D Y; Delgado, P L

2012-09-01

This study tested the hypothesis that abnormalities in components of the serotonin (5HT) system in the prefrontal cortex are associated with suicide in alcohol-dependent subjects. Second, we assessed the relationship of lifetime impulsivity and mood symptoms with prefrontal cortex 5-HT measures. Tissue was obtained from Brodmann's areas (BA) 9 and 24 in postmortem samples of individuals who were alcohol dependent with suicide (n = 5), alcohol dependent without suicide (n = 9) and normal controls (n = 5). Serotonin receptor (5HT) and serotonin reuptake transporter (SERT) mRNA were measured. Interviews with next of kin estimated lifetime impulsivity and mood symptoms in the last week of life. Serotonin receptor 1A (5HT1A) mRNA in BA 9 was elevated in the alcohol dependence without suicide group compared with controls. In the alcohol dependence with suicide group, anxiety symptoms were associated with decreased BA 24 SERT mRNA and depressive symptoms with BA 9 5HT1A mRNA expression. In the alcohol dependent only group impulsivity is correlated with increased BA 9, and BA 24 serotonin receptor 2A mRNA. Our data suggest region-specific change, rather than global serotonin blunting is involved in alcohol dependence and suicide. It also suggests that symptoms are differentially influenced by prefrontal cortex serotonin receptor mRNA levels. © 2011 John Wiley & Sons A/S.

Escitalopram prolonged fear induced by simulated public speaking and released hypothalamic-pituitary-adrenal axis activation.

Science.gov (United States)

Garcia-Leal, C; Del-Ben, C M; Leal, F M; Graeff, F G; Guimarães, F S

2010-05-01

Simulated public speaking (SPS) test is sensitive to drugs that interfere with serotonin-mediated neurotransmission and is supposed to recruit neural systems involved in panic disorder. The study was aimed at evaluating the effects of escitalopram, the most selective serotonin-selective reuptake inhibitor available, in SPS. Healthy males received, in a double-blind, randomized design, placebo (n = 12), 10 (n = 17) or 20 (n = 14) mg of escitalopram 2 hours before the test. Behavioural, autonomic and neuroendocrine measures were assessed. Both doses of escitalopram did not produce any effect before or during the speech but prolonged the fear induced by SPS. The test itself did not significantly change cortisol and prolactin levels but under the higher dose of escitalopram, cortisol and prolactin increased immediately after SPS. This fear-enhancing effect of escitalopram agrees with previously reported results with less selective serotonin reuptake inhibitors and the receptor antagonist ritanserin, indicating that serotonin inhibits the fear of speaking in public.

Psychopharmacologic treatment and blood transfusion in fast-track total hip and knee arthroplasty

DEFF Research Database (Denmark)

Gylvin, Silas Hinsch; Jørgensen, Christoffer Calov; Fink-Jensen, Anders

2017-01-01

BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) and other psychotropics are receiving increasing attention due to reports on inhibition of thrombocyte function and an increased bleeding risk in surgical settings. Studies in total hip and total knee arthroplasty (THA and TKA...

FLUOXETINE INCREASES INSULIN ACTION IN OBESE NONDIABETIC AND IN OBESE NON-INSULIN-DEPENDENT DIABETIC INDIVIDUALS

NARCIS (Netherlands)

Potter van Loon, B. J.; Radder, J. K.; Froelich, M.; Krans, H. M.; Zwinderman, A. H.; Meinders, A. E.

1992-01-01

Insulin resistance contributes to the metabolic defects in non-insulin-dependent diabetes mellitus (NIDDM). Anorectic agents have been shown to improve insulin action in NIDDM, irrespective of weight reduction. The serotonin-reuptake inhibiting agent fluoxetine has recently been recognized as an

A neurobiological perspective on attachment problems in sexual offenders and the role of selective serotonin re-uptake inhibitors in the treatment of such problems.

Science.gov (United States)

Beech, Anthony R; Mitchell, Ian J

2005-02-01

This paper describes what is currently known about attachment from the development, social-cognitive and biological literatures and outlines the impact on organisms given adverse development experiences that can have an effect upon attachment formation in childhood across these three literatures. We then describe the effects that 'insecure' attachment styles arising in childhood can affect brain chemistry and brain function and subsequently adult social/romantic relationships. In the paper, we note that a number of sexual offenders report adverse childhood experiences and that they possess attachment styles that, taken together, make it likely that they will either seek out intimate attachments in ways where they will have sex with children, perhaps confusing sex with intimacy or in aggressive ways as particularly happens with men who sexually assault adult women. The last section of the paper describes chemical treatment for sexual offenders, focusing on the use of selective serotonin re-uptake inhibitors (SSRIs). We note evidence for the role of SSRIs in promoting more social/affiliative behaviors and speculate on the effects that SSRIs have in the treatment of sexual offenders by targeting areas of the social brain. Here, we would argue that it would be useful to carry out treatment where there is a combination of SSRI treatment (to promote more prosocial feelings and behaviors) in conjunction with therapy that typically addresses thoughts and behaviors, i.e., cognitive-behavioral therapy/schema-focused therapy.

Fluoxetine: a case history of its discovery and preclinical development

OpenAIRE

Perez-Caballero, Laura; Torres-Sanchez, Sonia; Bravo, Lidia; Mico, Juan A.; Berrocoso, Esther

2014-01-01

Introduction: Depression is a multifactorial mood disorder with a high prevalence worldwide. Until now, treatments for depression have focused on the inhibition of monoaminergic reuptake sites, which augment the bioavailability of monoamines in the CNS. Advances in drug discovery have widened the therapeutic options with the synthesis of so-called selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine. Areas covered: The aim of this case history is to describe and discuss the ...

Involvement of spinal serotonin receptors in the regulation of intraspinal acetylcholine release.

Science.gov (United States)

Kommalage, Mahinda; Höglund, A Urban

2005-02-21

Stimulation of spinal serotonin (5-HT) receptors results in analgesia and release of acetylcholine. We investigated the involvement of 5-HT1, 5-HT2, and 5-HT3 receptor subtypes in the regulation of spinal acetylcholine release. A spinal microdialysis probe was placed dorsally at about the C5 level in anaesthetized rats. The selective serotonin reuptake inhibitor citalopram was found to increase acetylcholine release when infused via the microdialysis probe. Several doses of the 5-HT receptor agonists 8-hydroxy-2-(di-n-propylamino)tetraline (8-OH-DPAT, 5-HT1A), 1,4-dihydro-3-(1,2,3,6-tetrahydro-4-pyridinyl)-5H-pyrrolo[3,2-b]pyridin-5-one dihydrochloride (CP93129, 5-HT1B), alpha-methyl-5-hydroxytryptamine maleate (m5-HT, 5-HT2), 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI, 5-HT2C), and 1-(m-chlorophenyl)-biguanide (5-HT3) were subsequently infused via the microdialysis probe. Only 8-OH-DPAT, CP93129, and m5-HT increased acetylcholine release dose dependently. The 5-HT1A receptor selective antagonist (S)-N-tert-butyl-3-(4-(2-methoxyphenyl)piperazine-1-yl)-2-phenylpropanamide hydrochloride and the 5-HT2A receptor selective antagonist ketanserin tartrate inhibited the 8-OH-DPAT and the m5-HT induced acetylcholine release. The results suggest that 5-HT1A and the 5-HT2A receptors are involved in the regulation of acetylcholine release in the spinal cord.

Importance of the Extracellular Loop 4 in the Human Serotonin Transporter for Inhibitor Binding and Substrate Translocation*

Science.gov (United States)

Rannversson, Hafsteinn; Wilson, Pamela; Kristensen, Kristina Birch; Sinning, Steffen; Kristensen, Anders Skov; Strømgaard, Kristian; Andersen, Jacob

2015-01-01

The serotonin transporter (SERT) terminates serotonergic neurotransmission by performing reuptake of released serotonin, and SERT is the primary target for antidepressants. SERT mediates the reuptake of serotonin through an alternating access mechanism, implying that a central substrate site is connected to both sides of the membrane by permeation pathways, of which only one is accessible at a time. The coordinated conformational changes in SERT associated with substrate translocation are not fully understood. Here, we have identified a Leu to Glu mutation at position 406 (L406E) in the extracellular loop 4 (EL4) of human SERT, which induced a remarkable gain-of-potency (up to >40-fold) for a range of SERT inhibitors. The effects were highly specific for L406E relative to six other mutations in the same position, including the closely related L406D mutation, showing that the effects induced by L406E are not simply charge-related effects. Leu406 is located >10 Å from the central inhibitor binding site indicating that the mutation affects inhibitor binding in an indirect manner. We found that L406E decreased accessibility to a residue in the cytoplasmic pathway. The shift in equilibrium to favor a more outward-facing conformation of SERT can explain the reduced turnover rate and increased association rate of inhibitor binding we found for L406E. Together, our findings show that EL4 allosterically can modulate inhibitor binding within the central binding site, and substantiates that EL4 has an important role in controlling the conformational equilibrium of human SERT. PMID:25903124

Atomoxetine, a norepinephrine reuptake inhibitor, reduces seizure-induced respiratory arrest.

Science.gov (United States)

Zhang, Honghai; Zhao, Haiting; Feng, Hua-Jun

2017-08-01

Sudden unexpected death in epilepsy (SUDEP) is a devastating epilepsy complication, and no effective preventive strategies are currently available for this fatal disorder. Clinical and animal studies of SUDEP demonstrate that seizure-induced respiratory arrest (S-IRA) is the primary event leading to death after generalized seizures in many cases. Enhancing brain levels of serotonin reduces S-IRA in animal models relevant to SUDEP, including the DBA/1 mouse. Given that serotonin in the brain plays an important role in modulating respiration and arousal, these findings suggest that deficits in respiration and/or arousal may contribute to S-IRA. It is well known that norepinephrine is an important neurotransmitter that modulates respiration and arousal in the brain as well. Therefore, we hypothesized that enhancing noradrenergic neurotransmission suppresses S-IRA. To test this hypothesis, we examined the effect of atomoxetine, a norepinephrine reuptake inhibitor (NRI), on S-IRA evoked by either acoustic stimulation or pentylenetetrazole in DBA/1 mice. We report the original observation that atomoxetine specifically suppresses S-IRA without altering the susceptibility to seizures evoked by acoustic stimulation, and atomoxetine also reduces S-IRA evoked by pentylenetetrazole in DBA/1 mice. Our data suggest that the noradrenergic signaling is importantly involved in S-IRA, and that atomoxetine, a medication widely used to treat attention deficit hyperactivity disorder (ADHD), is potentially useful to prevent SUDEP. Copyright © 2017 Elsevier Inc. All rights reserved.

Peripheral serotonin regulates maternal calcium trafficking in mammary epithelial cells during lactation in mice.

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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.

Facilitation of acetylcholine release in rat frontal cortex by indeloxazine hydrochloride: involvement of endogenous serotonin and 5-HT4 receptors.

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Yamaguchi, T; Suzuki, M; Yamamoto, M

1997-12-01

Effects of indeloxazine hydrochloride, an inhibitor of serotonin (5-HT) and norepinephrine (NE) reuptake with a facilitatory effect on 5-HT release, on acetylcholine (ACh) output in frontal cortex of conscious rats were characterized using an in vivo microdialysis technique. Systemic administration of indeloxazine (3 and 10 mg/kg, i.p.) increased ACh and 5-HT output in a dose-dependent manner. Depletion of endogenous monoamines by reserpine and of 5-HT by p-chlorophenylalanine, but not that of catecholamines by alpha-methyl-p-tyrosine, significantly attenuated the facilitatory effect of indeloxazine on ACh release. When applied locally by reverse dialysis, indeloxazine (10 and 30 microM) and the selective 5-HT reuptake inhibitor citalopram (10 microM), but not the NE reuptake inhibitor maprotiline (30 microM), increased cortical ACh output. Indeloxazine (10 mg/kg)-induced increase in ACh release was significantly inhibited by local application of the 5-HT4 receptor antagonists RS23597 (50 microM) and GR113803 (1 microM), while the 5-HT1A antagonist WAY-100135 (100 microM), 5-HT1A/1B/beta-adrenoceptor antagonist (-)propranolol (150 microM), 5-HT2A/2C antagonist ritanserin (10 microM) and 5-HT3 antagonist ondansetron (10 microM) failed to significantly modify this effect. Neither depletion of monoamines nor treatment with serotonergic antagonists significantly changed the basal ACh level, indicating that endogenous monoamines do not tonically activate ACh release. These results suggest that indeloxazine-induced facilitation of ACh release in rat frontal cortex is mediated by endogenous 5-HT and involves at least in part cortical 5-HT4 receptors.

APRESS: apical regulatory super system, serotonin, and dopamine interaction

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Hinz M

2011-08-01

Full Text Available Marty Hinz1, Alvin Stein2, Thomas Uncini31Clinical Research, NeuroResearch Clinics, Inc, Cape Coral, FL, USA; 2Stein Orthopedic Associates, Plantation, FL, USA; 3DBS Labs, Duluth, MN, USABackground: The monoamines serotonin and dopamine are known to exist in two separate states: the endogenous state and the competitive inhibition state. The presence of the competitive inhibition state has been known to science for many years, but from a functional standpoint it has been noted in the literature as being "meaningless."Methods: A large database of monoamine transporter response to amino acid precursor administration variations with clinical outcomes was accumulated. In the process, a new organic cation transporter (OCT model has been published, and OCT functional status determination along with amino acid precursor manipulation methods have been invented and refined.Results: Methodology was developed whereby manipulation of the OCT, in the competitive inhibition state, is carried out in a predictable manner. This, in turn, has disproved the long-held assertion that the monoamine competitive inhibition state is functionally meaningless.Conclusion: The most significant aspect of this paper is the documentation of newly recognized relationships between serotonin and dopamine. When transport of serotonin and dopamine are both in the competitive inhibition state, manipulation of the concentrations of one will lead to predictable changes in concentrations of the other. From a functional standpoint, processes regulated and controlled by changes to only serotonin can now be controlled by changes to dopamine, and vice versa, in a predictable manner.Keywords: catecholamine, monoamine, competitive inhibition state

A comparative review of escitalopram, paroxetine, and sertraline: Are they all alike?

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Sanchez, Connie; Reines, Elin H; Montgomery, Stuart A

2014-07-01

It is known that newer antidepressants, such as the selective serotonin reuptake inhibitors (SSRIs), provide advantages in tolerability over antidepressants such as the tricyclics. However, even within the SSRI class, differences in efficacy or tolerability exist between the individual drugs. Among the three most widely prescribed SSRIs are paroxetine, sertraline, and escitalopram. Escitalopram is commonly referred to as an SSRI, but also has well-documented allosteric properties, and thus can be further classed as an allosteric serotonin reuptake inhibitor. All three antidepressants are efficacious compared with placebo, but there is evidence that escitalopram is more effective than a range of other antidepressants. There are no direct data to regard either paroxetine or sertraline as a superior antidepressant. Escitalopram is superior compared with paroxetine, which has a less favorable tolerability profile. Paroxetine is associated with cholinergic muscarinic antagonism and potent inhibition of CYP2D6, and sertraline has moderate drug interaction issues in comparison with escitalopram. Overall, as an allosteric serotonin reuptake inhibitor that is somewhat different from classical SSRIs, escitalopram is the first choice judged by combined efficacy and tolerability, and nonclinical data have offered possible mechanisms through which escitalopram could be more efficacious, based on its interaction with orthosteric and allosteric binding sites at the serotonin transporter.

Developmental exposure to fluoxetine modulates the serotonin system in hypothalamus.

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Cecilia Berg

Full Text Available The selective serotonin reuptake inhibitor (SSRI fluoxetine (FLU, Prozac® is commonly prescribed for depression in pregnant women. This results in SSRI exposure of the developing fetus. However, there are knowledge gaps regarding the impact of SSRI exposure during development. Given the role of serotonin in brain development and its cross-talk with sex hormone function, we investigated effects of developmental exposure to pharmacologically relevant concentrations of FLU (3 and 30 nM (measured on brain neurotransmitter levels, gonadal differentiation, aromatase activity in brain and gonads, and the thyroid system, using the Xenopus tropicalis model. Tadpoles were chronically exposed (8 weeks until metamorphosis. At metamorphosis brains were cryosectioned and levels of serotonin, dopamine, norepinephrine, and their metabolites 5-hydroxyindoleacetic acid, 3,4-dihydroxyphenylacetic acid, and homovanillic acid were measured in discrete regions (telencephalon, hypothalamus and the reticular formation of the cryosections using high-performance liquid chromatography. Exposure to 30 nM FLU increased the concentration of 5-hydroxyindoleacetic acid in hypothalamus compared with controls. FLU exposure did not affect survival, time to metamorphosis, thyroid histology, gonadal sex differentiation, or aromatase activity implying that the effect on the serotonergic neurotransmitter system in the hypothalamus region was specific. The FLU concentration that impacted the serotonin system is lower than the concentration measured in umbilical cord serum, suggesting that the serotonin system of the developing brain is highly sensitive to in utero exposure to FLU. To our knowledge this is the first study showing effects of developmental FLU exposure on brain neurochemistry. Given that SSRIs are present in the aquatic environment the current results warrant further investigation into the neurobehavioral effects of SSRIs in aquatic wildlife.

Determination of venlafaxine and O-desmethylvenlafaxine in dried blood spots using LC-MS/MS

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Berm, E.J.J.; Brummel-Mulder, E.; Paardekooper, J.; Hak, E.; Wilffert, B.; Maring, J.G.

2013-01-01

Background: Venlafaxine (VEN) is an antidepressant which exerts both serotonin and norepinephrine reuptake inhibition. The drug is mainly metabolized by CYP2D6 to its active metabolite O-desmetylvenlafaxine (ODMV). Due to large interindividual differences in clearance in which genetic variance in

From non-pharmacological treatments for post-traumatic stress disorder to novel therapeutic targets

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Hendriksen, Erik; Olivier, Berend; Oosting, Ronald S

2014-01-01

The development of new pharmacological therapies starts with target discovery. Finding new therapeutic targets for anxiety disorders is a difficult process. Most of the currently described drugs for post-traumatic stress disorder (PTSD) are based on the inhibition of serotonin reuptake. The

Optogenetic activation of dorsal raphe serotonin neurons enhances patience for future rewards.

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Miyazaki, Kayoko W; Miyazaki, Katsuhiko; Tanaka, Kenji F; Yamanaka, Akihiro; Takahashi, Aki; Tabuchi, Sawako; Doya, Kenji

2014-09-08

Serotonin is a neuromodulator that is involved extensively in behavioral, affective, and cognitive functions in the brain. Previous recording studies of the midbrain dorsal raphe nucleus (DRN) revealed that the activation of putative serotonin neurons correlates with the levels of behavioral arousal [1], rhythmic motor outputs [2], salient sensory stimuli [3-6], reward, and conditioned cues [5-8]. The classic theory on serotonin states that it opposes dopamine and inhibits behaviors when aversive events are predicted [9-14]. However, the therapeutic effects of serotonin signal-enhancing medications have been difficult to reconcile with this theory [15, 16]. In contrast, a more recent theory states that serotonin facilitates long-term optimal behaviors and suppresses impulsive behaviors [17-21]. To test these theories, we developed optogenetic mice that selectively express channelrhodopsin in serotonin neurons and tested how the activation of serotonergic neurons in the DRN affects animal behavior during a delayed reward task. The activation of serotonin neurons reduced the premature cessation of waiting for conditioned cues and food rewards. In reward omission trials, serotonin neuron stimulation prolonged the time animals spent waiting. This effect was observed specifically when the animal was engaged in deciding whether to keep waiting and was not due to motor inhibition. Control experiments showed that the prolonged waiting times observed with optogenetic stimulation were not due to behavioral inhibition or the reinforcing effects of serotonergic activation. These results show, for the first time, that the timed activation of serotonin neurons during waiting promotes animals' patience to wait for a delayed reward. Copyright © 2014 Elsevier Ltd. All rights reserved.

The evolution of violence in men: the function of central cholesterol and serotonin.

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Wallner, Bernard; Machatschke, Ivo H

2009-04-30

Numerous studies point to central serotonin as an important modulator of maladaptive behaviors. In men, for instance, low concentrations of this neurotransmitter are related to hostile aggression. A key player in serotonin metabolism seems to be central cholesterol. It plays a fundamental role in maintaining the soundness of neuron membranes, especially in the exocytosis transport of serotonin vesicles into the synaptic cleft. In this review, we attempt an evolutionary approach to the neurobiological basis of human male violence. Hominid evolution was shaped by periods of starvation but also by energy demands of an increasingly complex brain. A lack of food resources reduces uptake of glucose and results in a decreased energy-supply for autonomous brain cholesterol synthesis. Consequently, concentrations of neuromembrane cholesterol decrease, which lead to a failure of the presynaptic re-uptake mechanism of serotonin and ultimately to low central serotonin. We propose that starvation might have affected the larger male brains earlier than those of females. Furthermore, this neurophysiological process diminished the threshold for hostile aggression, which in effect represented a prerequisite for being a successful hunter or scavenger. In a Darwinian sense, the odds to acquire reliable energetic resources made those males to attractive spouses in terms of paternal care and mate support. To underpin these mechanisms, a hypothetical four-stage model of synaptic membrane destabilization effected by a prolonged shortage of high-energy, cholesterol-containing food is illustrated.

The role of serotonin in impulsive aggression, suicide, and homicide in adolescents and adults: a literature review.

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Glick, Amy R

2015-05-01

This is a literature review discussing previous studies on the associations between impulsive aggression and the serotonergic system in adults, adolescents, and children. The review demonstrates that there is a clear association between low cerebrospinal fluid serotonin and impulsive aggression. However, studies on neurotransmitter receptor profiles, functional imaging, genetics, and epigenetics reviewed in this article suggest a more complicated picture that includes consideration of gene vs. environment in the evaluation of risk. Serotonin supplementation studies suggest that selective serotonin reuptake inhibitors may reduce impulsive aggression in some adults but are less effective in adults with pathological aggression and also in children and adolescents. Child and adolescent studies are less conclusive, in part due to the heterogeneous physiologic and psychosocial changes occurring over the course of development. The author thus concludes that psychiatrists can reduce risk in these special patient populations by creating safer environments in the form of changes in policy and increased support services.

Farmacogenética de inibidores seletivos de recaptação de serotonina: uma revisão Pharmacogenetics of selective serotonine reuptake inhibitors: a review

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Diana Klanovicz Silva

2008-01-01

Full Text Available A variabilidade da resposta aos medicamentos se deve em grande parte a fatores genéticos, e essa variabilidade afeta os efeitos terapêuticos e as reações adversas, de forma que a mesma dose de um medicamento pode ser benéfica para um paciente mas ineficaz para outro. Os fármacos conhecidos como inibidores seletivos de recaptação de serotonina (ISRSs pertencem a uma classe de medicamentos utilizados para o tratamento de uma série de patologias relacionadas com a serotonina, especialmente a depressão. O objetivo deste trabalho é reunir os dados presentes na literatura sobre a associação de genes candidatos com a resposta a ISRSs, fornecendo assim um panorama sobre o estado atual de conhecimento sobre o assunto. A resposta ao tratamento com ISRSs depende da variabilidade de genes codificantes de proteínas envolvidas com o papel da serotonina no cérebro. Com os avanços conquistados a partir do Projeto Genoma Humano, foi possível detectar essas variações, e várias delas mostraram ter importância farmacogenética. Portanto, alguns dos genes relacionados à farmacogenética dos ISRSs já são conhecidos, o que torna clara a necessidade de maiores investigações prospectivas para determinar a real utilidade desse conhecimento na prática clínica, com relação à possibilidade da determinação da dose adequada do fármaco correto para cada paciente, prática que vem sendo denominada de "medicina personalizada".A large proportion of the variability in drug response is due to genetic factors, and this variability affects therapeutic effects and adverse reactions, so that the same dosage of a drug can be beneficial to some patients, but ineffective to others. The drugs known as selective serotonin reuptake inhibitors (SSRI belong to a pharmacological class used in the management of a number of diseases related to serotonin, especially depression. The aim of this paper is to collect data from the literature about the association of

Inhibition of G-Protein-Activated Inwardly Rectifying K+ Channels by the Selective Norepinephrine Reuptake Inhibitors Atomoxetine and Reboxetine

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Kobayashi, Toru; Washiyama, Kazuo; Ikeda, Kazutaka

2010-01-01

Atomoxetine and reboxetine are commonly used as selective norepinephrine reuptake inhibitors (NRIs) for the treatment of attention-deficit/hyperactivity disorder and depression, respectively. Furthermore, recent studies have suggested that NRIs may be useful for the treatment of several other psychiatric disorders. However, the molecular mechanisms underlying the various effects of NRIs have not yet been sufficiently clarified. G-protein-activated inwardly rectifying K+ (GIRK or Kir3) channels have an important function in regulating neuronal excitability and heart rate, and GIRK channel modulation has been suggested to be a potential treatment for several neuropsychiatric disorders and cardiac arrhythmias. In this study, we investigated the effects of atomoxetine and reboxetine on GIRK channels using the Xenopus oocyte expression assay. In oocytes injected with mRNA for GIRK1/GIRK2, GIRK2, or GIRK1/GIRK4 subunits, extracellular application of atomoxetine or reboxetine reversibly reduced GIRK currents. The inhibitory effects were concentration-dependent, but voltage-independent, and time-independent during each voltage pulse. However, Kir1.1 and Kir2.1 channels were insensitive to atomoxetine and reboxetine. Atomoxetine and reboxetine also inhibited GIRK currents induced by activation of cloned A1 adenosine receptors or by intracellularly applied GTPγS, a nonhydrolyzable GTP analogue. Furthermore, the GIRK currents induced by ethanol were concentration-dependently inhibited by extracellularly applied atomoxetine but not by intracellularly applied atomoxetine. The present results suggest that atomoxetine and reboxetine inhibit brain- and cardiac-type GIRK channels, revealing a novel characteristic of clinically used NRIs. GIRK channel inhibition may contribute to some of the therapeutic effects of NRIs and adverse side effects related to nervous system and heart function. PMID:20393461

Use of anti-depressants and the risk of fracture of the hip or femur

OpenAIRE

van den Brand, M. W. M.; Samson, M. M.; Pouwels, S.; van Staa, T. P.; Thio, B.; Cooper, C.; Leufkens, H. G. M.; Egberts, A. C. G.; Verhaar, H. J. J.; de Vries, F.

2009-01-01

Summary Anti-depressants are used largely, but have serious side effects. We show that both selective serotonin re-uptake inhibitors (SSRIs) and tricyclic anti-depressants (TCAs) increase the risk of hip/femur fracture and that this risk is time related and depends on the degree of serotonin transporter inhibition. This should be considered when prescribing anti-depressants to patients. Introduction Anti-depressants are known to have serious side effects. We examined the association between t...

Serotonin Syndrome after Sertraline Overdose in a Child: A Case Report

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Joana Grenha

2013-01-01

Full Text Available Serotonin syndrome is a potentially life-threatening drug effect. It may be misdiagnosed because it has mostly been reported in adults. Case Report. An 8-year-old girl with behavioral problems and medicated with risperidone and sertraline was admitted in the emergency department after she had taken voluntarily 1500 mg of sertraline (50 mg/kg. At admission, she had marked agitation, visual hallucinations, diaphoresis, flushing, and tremor. She had fever and periods of hypertension. She also showed generalized rigidity and involuntary movements. She was treated with fluids and iv diazepam, midazolam, clemastine, and biperiden. As the patient presented a severe insomnia and a progressive rhabdomyolysis, she was transferred to pediatric intensive care unit (ICU, where she was under treatment with cyproheptadine, mechanical ventilation, and muscular paralysis for 11 days. She was discharged from hospital a few days later with no neurological sequelae. Conclusions. Serotonin syndrome is still not well recognized by physicians. In our patient, the diagnosis was made early due to the history of overdose with serotonin reuptake inhibitors and the triad of mental, neurological, and autonomic signs. Parents must be educated to prevent children from having free access to drugs, avoiding self-medication or overdose.

Randomized controlled trials of serotonin-norepinephrine reuptake inhibitor in treating major depressive disorder in children and adolescents: a meta-analysis of efficacy and acceptability

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Y. Xu

2016-01-01

Full Text Available New generation antidepressant therapies, including serotonin-norepinephrine reuptake inhibitor (SNRIs, were introduced in the late 1980s; however, few comprehensive studies have compared the benefits and risks of various contemporary treatments for major depressive disorder (MDD in young patients. A comprehensive literature search of PubMed, Cochrane, Embase, Web of Science, and PsycINFO databases was conducted from 1970 to January 2015. Only clinical trials that randomly assigned one SNRI or placebo to patients aged 7 to 18 years who met the diagnostic criteria for major depressive disorder were included. Treatment success, dropout rate, and suicidal ideation/attempt outcomes were measured. Primary efficacy was determined by pooling the risk ratios (RRs of treatment response and remission. Acceptability was determined by pooling the RRs of dropouts for all reasons and for adverse effects as well as suicide-risk outcomes. Five trials with a total of 973 patients were included. SNRIs were not significantly more effective than placebo for treatment response but were for remission. The comparison of patients taking SNRIs that dropped out for all reasons and those taking placebo did not reach statistical significance. Significantly more patients taking SNRIs dropped out for adverse effects than those taking placebo. No significant difference was found in suicide-related risk outcomes. SNRI therapy does not display a superior efficacy and is not better tolerated compared to placebo in these young patients. However, duloxetine has a potential beneficial effect for depression in young populations, showing a need for further research.

Design and synthesis of 4-heteroaryl 1,2,3,4-tetrahydroisoquinolines as triple reuptake inhibitors.

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Liu, Shuang; Zha, Congxiang; Nacro, Kassoum; Hu, Min; Cui, Wenge; Yang, Yuh-Lin; Bhatt, Ulhas; Sambandam, Aruna; Isherwood, Matthew; Yet, Larry; Herr, Michael T; Ebeltoft, Sarah; Hassler, Carla; Fleming, Linda; Pechulis, Anthony D; Payen-Fornicola, Anne; Holman, Nicholas; Milanowski, Dennis; Cotterill, Ian; Mozhaev, Vadim; Khmelnitsky, Yuri; Guzzo, Peter R; Sargent, Bruce J; Molino, Bruce F; Olson, Richard; King, Dalton; Lelas, Snjezana; Li, Yu-Wen; Johnson, Kim; Molski, Thaddeus; Orie, Anitra; Ng, Alicia; Haskell, Roy; Clarke, Wendy; Bertekap, Robert; O'Connell, Jonathan; Lodge, Nicholas; Sinz, Michael; Adams, Stephen; Zaczek, Robert; Macor, John E

2014-07-10

A series of 4-bicyclic heteroaryl 1,2,3,4-tetrahydroisoquinoline inhibitors of the serotonin transporter (SERT), norepinephrine transporter (NET), and dopamine transporter (DAT) was discovered. The synthesis and structure-activity relationship (SAR) of these triple reuptake inhibitors (TRIs) will be discussed. Compound 10i (AMR-2), a very potent inhibitor of SERT, NET, and DAT, showed efficacy in the rat forced-swim and mouse tail suspension models with minimum effective doses of 0.3 and 1 mg/kg (po), respectively. At efficacious doses in these assays, 10i exhibited substantial occupancy levels at the three transporters in both rat and mouse brain. The study of the metabolism of 10i revealed the formation of a significant active metabolite, compound 13.

CaMKII inhibition with KN93 attenuates endothelin and serotonin receptor-mediated vasoconstriction and prevents subarachnoid hemorrhage-induced deficits in sensorimotor function

DEFF Research Database (Denmark)

Edvinsson, Lars; Povlsen, Gro Klitgaard; Ahnstedt, Hilda

2014-01-01

tested the hypothesis that inhibition of calcium calmodulin-dependent protein kinase II (CaMKII) may reduce cerebral vasoconstriction mediated by endothelin and serotonin receptors and improve neurological outcome after experimental SAH. METHODS: SAH was induced in adult rats by injection of 250 μ...

Possible association between serotonin transporter promoter region polymorphism and extremely violent crime in Chinese males.

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Liao, Ding-Lieh; Hong, Chen-Jee; Shih, Hao-Ling; Tsai, Shih-Jen

2004-01-01

The neurotransmitter, serotonin, has been implicated in aggressive behavior. The serotonin transporter (5-HTT), which reuptakes serotonin into the nerve terminal, plays a critical role in the regulation of serotonergic function. Previous western reports have demonstrated that the low-activity short (S) allele of the 5-HTT gene-linked polymorphic-region (5-HTTLPR) polymorphism is associated with aggressive behavior and associated personality traits. In the present study, we investigated this 5-HTTLPR genetic polymorphism in a group of Chinese males who had been convicted for extremely violent crime (n = 135) and a normal control group (n = 111). The proportion of S-allele carriers was significantly higher in the criminal group than in the controls (p = 0.006). A significant association was not demonstrated for the relationship between the 5-HTTLPR polymorphism and antisocial personality disorder, substance abuse or alcohol abuse in the criminal group. Our findings demonstrate that carriage of the low-activity S allele is associated with extremely violent criminal behavior in Chinese males, and suggests that the 5-HTT may be implicated in the mechanisms underlying violent behaviors.

Perinatal maternal stress and serotonin signaling: effects on pain sensitivity in offspring.

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Knaepen, Liesbeth; Pawluski, Jodi L; Patijn, Jacob; van Kleef, Maarten; Tibboel, Dick; Joosten, Elbert A

2014-07-01

It has been estimated that 20% of pregnant women are facing perinatal stress and depression. Perinatal maternal stress has been shown to increase pain sensitivity in offspring. For the treatment of their depressive symptoms, pregnant women are frequently prescribed selective serotonin reuptake inhibitors (SSRIs). Since the descending pain inhibitory circuit matures perinatally, perinatal SSRI exposure has been shown to affect pain sensitivity in offspring. In the present review, we summarize experimental and clinical evidence for the effect of perinatal maternal stress and SSRI exposure on pain sensitivity in offspring. Both experimental and clinical studies show the effect of perinatal maternal stress on regulation of the hypothalamic-pituitary-adrenal (HPA) system and the serotonin pain inhibitory system. Alterations in these two systems likely underlie long-term alterations in the development of pain sensitivity. This review sheds light on the effect of perinatal maternal stress and treatment with SSRIs on offspring pain sensitivity, in relation to the developing HPA system and 5-HT signaling. © 2013 Wiley Periodicals, Inc.

Calcium Signaling Pathway Is Associated with the Long-Term Clinical Response to Selective Serotonin Reuptake Inhibitors (SSRI and SSRI with Antipsychotics in Patients with Obsessive-Compulsive Disorder.

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Hidehiro Umehara

Full Text Available Selective serotonin reuptake inhibitors (SSRI are established first-line pharmacological treatments for obsessive-compulsive disorder (OCD, while antipsychotics are used as an augmentation strategy for SSRI in OCD patients who have either no response or a partial response to SSRI treatment. The goal of the present study was to identify genetic variants and pathways that are associated with the long-term clinical response of OCD patients to SSRI or SSRI with antipsychotics.We first performed a genome-wide association study of 96 OCD patients to examine genetic variants contributing to the response to SSRI or SSRI with antipsychotics. Subsequently, we conducted pathway-based analyses by using Improved Gene Set Enrichment Analysis for Genome-wide Association Study (i-GSEA4GWAS to examine the combined effects of genetic variants on the clinical response in OCD.While we failed to detect specific genetic variants associated with clinical responses to SSRI or to SSRI with an atypical antipsychotic at genome-wide levels of significance, we identified 8 enriched pathways for the SSRI treatment response and 5 enriched pathways for the treatment response to SSRI with an antipsychotic medication. Notably, the calcium signaling pathway was identified in both treatment responses.Our results provide novel insight into the molecular mechanisms underlying the variability in clinical response to SSRI and SSRI with antipsychotics in OCD patients.

Serotonin storage pools in basophil leukemia and mast cells: characterization of two types of serotonin binding protein and radioautographic analysis of the intracellular distribution of [3H]serotonin

International Nuclear Information System (INIS)

Tamir, H.; Theoharides, T.C.; Gershon, M.D.; Askenase, P.W.

1982-01-01

The binding of serotonin to protein(s) derived from rat basophil leukemia (RBL) cells and mast cells was studied. Two types of serotonin binding protein in RBL cells was found. These proteins differed from one another in molecular weight and eluted in separate peaks from sephadex G-200 columns. Peak I protein (KD = 1.9 x 10 -6 M) was a glycoprotein that bound to concanavalin A (Con A); Peak II protein (KD 1 = 4.5 x 10 - 8 M; KD 2 = 3.9 x 10 -6 M) did not bind to Con A. Moreover, binding of [ 3 H]serotonin to protein of Peak I was sensitive to inhibition by reserpine, while binding of [ 3 H]serotonin to protein of Peak II resisted inhibition by that drug. Other differences between the two types of binding protein were found, the most significant of which was the far more vigorous conditions of homogenization required to extract Peak I than Peak II protein. Electron microscope radioautographic analysis of the intracellular distribution of [ 3 H] serotonin taken up in vitro by RBL cells or in vivo by murine mast cells indicated that essentially all of the labeled amine was located in cytoplasmic granules.No evidence for a pool in the cytosol was found and all granules were capable of becoming labeled. The presence of two types of intracellular serotonin binding proteins in these cells may indicate that there are two intracellular storage compartments for the amine. Both may be intragranular, but Peak I protein may be associated with the granular membrane while Peak II protein may be more free within the granular core. Different storage proteins may help to explain the differential release of amines from mast cell granules

Importance of the Extracellular Loop 4 in the Human Serotonin Transporter for Inhibitor Binding and Substrate Translocation.

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Rannversson, Hafsteinn; Wilson, Pamela; Kristensen, Kristina Birch; Sinning, Steffen; Kristensen, Anders Skov; Strømgaard, Kristian; Andersen, Jacob

2015-06-05

The serotonin transporter (SERT) terminates serotonergic neurotransmission by performing reuptake of released serotonin, and SERT is the primary target for antidepressants. SERT mediates the reuptake of serotonin through an alternating access mechanism, implying that a central substrate site is connected to both sides of the membrane by permeation pathways, of which only one is accessible at a time. The coordinated conformational changes in SERT associated with substrate translocation are not fully understood. Here, we have identified a Leu to Glu mutation at position 406 (L406E) in the extracellular loop 4 (EL4) of human SERT, which induced a remarkable gain-of-potency (up to >40-fold) for a range of SERT inhibitors. The effects were highly specific for L406E relative to six other mutations in the same position, including the closely related L406D mutation, showing that the effects induced by L406E are not simply charge-related effects. Leu(406) is located >10 Å from the central inhibitor binding site indicating that the mutation affects inhibitor binding in an indirect manner. We found that L406E decreased accessibility to a residue in the cytoplasmic pathway. The shift in equilibrium to favor a more outward-facing conformation of SERT can explain the reduced turnover rate and increased association rate of inhibitor binding we found for L406E. Together, our findings show that EL4 allosterically can modulate inhibitor binding within the central binding site, and substantiates that EL4 has an important role in controlling the conformational equilibrium of human SERT. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Effect of Time-Dependent Selective Serotonin Reuptake Inhibitor Antidepressants During Pregnancy on Behavioral, Emotional, and Social Development in Preschool-Aged Children.

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Lupattelli, Angela; Wood, Mollie; Ystrom, Eivind; Skurtveit, Svetlana; Handal, Marte; Nordeng, Hedvig

2018-03-01

To evaluate the effect of prenatal exposure to selective serotonin reuptake inhibitors (SSRIs) on children's behavioral, emotional, and social development by age 5 years, and over time since age 1.5 years. The prospective Norwegian Mother and Child Cohort Study was linked to the Medical Birth Registry of Norway. We included women who reported depressive/anxiety disorders before and/or during pregnancy. Children born to women who used SSRIs in early (weeks 0-16), mid- (weeks 17-28), or late (> week 29) pregnancy were compared to those who were unexposed. Children's internalizing and externalizing behaviors (Child Behavior Checklist) and temperament traits (Emotionality, Activity and Shyness Temperament Questionnaire) were measured at 1.5, 3, and 5 years. Mean scores were calculated and standardized. General linear marginal structural models were fitted to account for time-varying exposure and confounders, and censoring; 3-level growth-curve models were used. A total of 8,359 mother-child dyads were included, and 4,128 children had complete outcome data at age 5 years. Children exposed to SSRIs in late pregnancy had an increased risk of anxious/depressed behaviors by age 5 years compared with unexposed children (adjusted β = 0.50, 95% CI = 0.04, 0.96). Such risk was not evident for earlier timings of exposure. There was no evidence for a substantial prenatal SSRI effect on externalizing, social, and emotional problems. These findings suggest no substantial increased risk for externalizing, emotional, or social problems in preschool-aged children following prenatal SSRI exposure. Although the role of chance and potential unmeasured confounding cannot be ruled out, late-pregnancy SSRI exposure was associated with greater anxious/depressed behaviors in the offspring. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

The Antidepressant 5-HT2A Receptor Antagonists Pizotifen and Cyproheptadine Inhibit Serotonin-Enhanced Platelet Function

Science.gov (United States)

Lin, Olivia A.; Karim, Zubair A.; Vemana, Hari Priya; Espinosa, Enma V. P.; Khasawneh, Fadi T.

2014-01-01

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 EMD 281014, their

Effect of ondansetron on the analgesic efficacy of tramadol used for ...

African Journals Online (AJOL)

However, its use has been associated with a higher .... Patients with a PONV score of 3 were treated with metoclopramide ... receptors.11 It also exerts analgesic effect by inhibiting serotonin and norepinephrine reuptake thereby blocking the nociceptive ... higher incidence of PONV.12 Ondansetron is a highly selective.

Uremic anorexia: a consequence of persistently high brain serotonin levels? The tryptophan/serotonin disorder hypothesis.

Science.gov (United States)

Aguilera, A; Selgas, R; Codoceo, R; Bajo, A

2000-01-01

Anorexia is a frequent part of uremic syndrome, contributing to malnutrition in dialysis patients. Many factors have been suggested as responsible for uremic anorexia. In this paper we formulate a new hypothesis to explain the appetite disorders in dialysis patients: "the tryptophan/serotonin disorder hypothesis." We review current knowledge of normal hunger-satiety cycle control and the disorders described in uremic patients. There are four phases in food intake regulation: (1) the gastric phase, during which food induces satiety through gastric distention and satiety peptide release; (2) the post absorptive phase, during which circulating compounds, including glucose and amino acids, cause satiety by hepatic receptors via the vagus nerve; (3) the hepatic phase, during which adenosine triphosphate (ATP) concentration is the main stimulus inducing hunger or satiety, with cytokines inhibiting ATP production; and (4) the central phase, during which appetite is regulated through peripheral (circulating plasma substances and neurotransmitters) and brain stimuli. Brain serotonin is the final target for peripheral mechanisms controlling appetite. High brain serotonin levels and a lower serotonin/dopamine ratio cause anorexia. Plasma and brain amino acid concentrations are recognized factors involved in neurotransmitter synthesis and appetite control. Tryptophan is the substrate of serotonin synthesis. High plasma levels of anorectics such as tryptophan (plasma and brain), cholecystokinin, tumor necrosis factor alpha, interleukin-1, and leptin, and deficiencies of nitric oxide and neuropeptide Y have been described in uremia; all increase intracerebral serotonin. We suggest that brain serotonin hyperproduction due to a uremic-dependent excess of tryptophan may be the final common pathway involved in the genesis of uremic anorexia. Various methods of ameliorating anorexia by decreasing the central effects of serotonin are proposed.

Three cases of zolpidem dependence treated with fluoxetine: the serotonin hypothesis.

Science.gov (United States)

Liappas, Ioannis A; Malitas, Petros N; Dimopoulos, Nikolaos P; Gitsa, Olympia E; Liappas, Alexandros I; Nikolaou, Chrisoula K; Christodoulou, Georgios N

2003-04-01

Zolpidem is an imidazopyridine hypnotic that is believed to act selectively at alpha(1) subunit-containing gamma-aminobutyric acid type A (GABA(A)) receptors and thus to have minimal abuse and dependence potential. We present three cases of zolpidem abuse and dependence in which the drug was used not for sedation but for stimulation and anxiolysis. All of the patients were treated with fluoxetine (a selective serotonin reuptake inhibitor) and managed to discontinue the abuse and remain abstinent from the drug. The efficacy of this kind of medication on the abuse of a GABAergic agonist, in this case dependence on zolpidem, leads to a serotonergic and GABAergic system interaction hypothesis.

Serotonin transporter occupancy by escitalopram and citalopram in the non-human primate brain: a [(11)C]MADAM PET study.

Science.gov (United States)

Finnema, Sjoerd J; Halldin, Christer; Bang-Andersen, Benny; Bundgaard, Christoffer; Farde, Lars

2015-11-01

A number of serotonin receptor positron emission tomography (PET) radioligands have been shown to be sensitive to changes in extracellular serotonin concentration, in a generalization of the well-known dopamine competition model. High doses of selective serotonin reuptake inhibitors (SSRIs) decrease serotonin receptor availability in monkey brain, consistent with increased serotonin concentrations. However, two recent studies on healthy human subjects, using a single, lower and clinically relevant SSRI dose, showed increased cortical serotonin receptor radioligand binding, suggesting potential decreases in serotonin concentration in projection regions when initiating treatment. The cross-species differential SSRI effect may be partly explained by serotonin transporter (SERT) occupancy in monkey brain being higher than is clinically relevant. We here determine SERT occupancy after single doses of escitalopram or citalopram by conducting PET measurements with [(11)C]MADAM in monkeys. Relationships between dose, plasma concentration and SERT occupancy were estimated by one-site binding analyses. Binding affinity was expressed as dose (ID50) or plasma concentration (K i) where 50 % SERT occupancy was achieved. Estimated ID50 and K i values were 0.020 mg/kg and 9.6 nmol/L for escitalopram and 0.059 mg/kg and 9.7 nmol/L for citalopram, respectively. Obtained K i values are comparable to values reported in humans. Escitalopram or citalopram doses nearly saturated SERT in previous monkey studies which examined serotonin sensitivity of receptor radioligands. PET-measured cross-species differential effects of SSRI on cortical serotonin concentration may thus be related to SSRI dose. Future monkey studies using SSRI doses inducing clinically relevant SERT occupancy may further illuminate the delayed onset of SSRI therapeutic effects.

Evaluation of interleukin-6 and serotonin as biomarkers to predict response to fluoxetine.

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Manoharan, Aarthi; Rajkumar, Ravi Philip; Shewade, Deepak Gopal; Sundaram, Rajan; Muthuramalingam, Avin; Paul, Abialbon

2016-05-01

Only 30% of major depressive disorder (MDD) patients achieve complete remission with a serotonergic antidepressant (selective serotonin reuptake inhibitor). We investigated the potential of serotonin (5-HT) and interleukin-6 (IL-6) to serve as functional biomarkers of fluoxetine response. Serum IL-6 and 5-HT were measured in 73 MDD patients (39 responders and 34 non-responders) pre- and 6 weeks post-treatment and in 44 normal controls with ELISA. Fluoxetine and norfluoxetine were measured using LC MS/MS. IL-6 levels were significantly higher in MDD patients when compared with controls (p Fluoxetine and norfluoxetine concentrations were not significantly different in responders and non-responders, and there was no correlation between fluoxetine concentrations and percentage reduction in 5-HT from week 0 to 6. 5-HT and IL-6 may not serve as useful markers of response to fluoxetine because of inconsistent results across different studies. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Biaryls as potent, tunable dual neurokinin 1 receptor antagonists and serotonin transporter inhibitors.

Science.gov (United States)

Degnan, Andrew P; Tora, George O; Han, Ying; Rajamani, Ramkumar; Bertekap, Robert; Krause, Rudolph; Davis, Carl D; Hu, Joanna; Morgan, Daniel; Taylor, Sarah J; Krause, Kelly; Li, Yu-Wen; Mattson, Gail; Cunningham, Melissa A; Taber, Matthew T; Lodge, Nicholas J; Bronson, Joanne J; Gillman, Kevin W; Macor, John E

2015-08-01

Depression is a serious illness that affects millions of patients. Current treatments are associated with a number of undesirable side effects. Neurokinin 1 receptor (NK1R) antagonists have recently been shown to potentiate the antidepressant effects of serotonin-selective reuptake inhibitors (SSRIs) in a number of animal models. Herein we describe the optimization of a biaryl chemotype to provide a series of potent dual NK1R antagonists/serotonin transporter (SERT) inhibitors. Through the choice of appropriate substituents, the SERT/NK1R ratio could be tuned to afford a range of target selectivity profiles. This effort culminated in the identification of an analog that demonstrated oral bioavailability, favorable brain uptake, and efficacy in the gerbil foot tap model. Ex vivo occupancy studies with compound 58 demonstrated the ability to maintain NK1 receptor saturation (>88% occupancy) while titrating the desired level of SERT occupancy (11-84%) via dose selection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of LSD on grooming behavior in serotonin transporter heterozygous (Sert⁺/⁻) mice.

Science.gov (United States)

Kyzar, Evan J; Stewart, Adam Michael; Kalueff, Allan V

2016-01-01

Serotonin (5-HT) plays a crucial role in the brain, modulating mood, cognition and reward. The serotonin transporter (SERT) is responsible for the reuptake of 5-HT from the synaptic cleft and regulates serotonin signaling in the brain. In humans, SERT genetic variance is linked to the pathogenesis of various psychiatric disorders, including anxiety, autism spectrum disorders (ASD) and obsessive-compulsive disorder (OCD). Rodent self-grooming is a complex, evolutionarily conserved patterned behavior relevant to stress, ASD and OCD. Genetic ablation of mouse Sert causes various behavioral deficits, including increased anxiety and grooming behavior. The hallucinogenic drug lysergic acid diethylamide (LSD) is a potent serotonergic agonist known to modulate human and animal behavior. Here, we examined heterozygous Sert(+/-) mouse behavior following acute administration of LSD (0.32 mg/kg). Overall, Sert(+/-) mice displayed a longer duration of self-grooming behavior regardless of LSD treatment. In contrast, LSD increased serotonin-sensitive behaviors, such as head twitching, tremors and backwards gait behaviors in both Sert(+/+) and Sert(+/-) mice. There were no significant interactions between LSD treatment and Sert gene dosage in any of the behavioral domains measured. These results suggest that Sert(+/-) mice may respond to the behavioral effects of LSD in a similar manner to wild-type mice. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterization and regulation of [3H]-serotonin uptake and release in rodent spinal

International Nuclear Information System (INIS)

Stauderman, K.A.

1986-01-01

The uptake and release of [ 3 H]-serotonin were investigated in rat spinal cord synaptosomes. In the uptake experiments, sodium-dependent and sodium-independent [ 3 H]-serotonin accumulation processes were found. Sodium-dependent [ 3 H]-serotonin accumulation was: linear with sodium concentrations up to 180 mM; decreased by disruption of membrane integrity or ionic gradients; associated with purified synaptosomal fractions; and reduced after description of descending serotonergic neurons in the spinal cord. Of the uptake inhibitors tested, the most potent was fluoxetine (IC 50 75 nM), followed by desipramine (IC 50 430 nM) and nomifensine (IC 50 950 nM). The sodium-independent [ 3 H]-serotonin accumulation process was insensitive to most treatments and probably represents nonspecific membrane binding. Thus, only sodium-dependent [ 3 H]-serotonin uptake represents the uptake process of serotonergic nerve terminals in rat spinal cord homogenates. In the release experiments, K + -induced release of previously accumulated [ 3 H]-serotonin was Ca 2+ -dependent, and originated from serotonergic synaptosomes. Exogenous serotonin and 5-methyoxy-N,N-dimethyltryptamine inhibited [ 3 H]-serotonin release in a concentration-dependent way. Of the antagonists tested, only methiothepin effectively blocked the effect of serotonin. These data support the existence of presynaptic serotonin autoreceptors on serotonergic nerve terminals in the rat spinal cord that act to inhibit a voltage and Ca 2+ -sensitive process linked to serotonin release. Alteration of spinai cord serotonergic function may therefore be possible by drugs acting on presynaptic serotonin autoreceptors in the spinal cord

Normal Bone Microstructure and Density But Worse Physical Function in Older Women Treated with Selective Serotonin Reuptake Inhibitors, a Cross-Sectional Population-Based Study.

Science.gov (United States)

Larsson, Berit; Mellström, Dan; Johansson, Lisa; Nilsson, Anna G; Lorentzon, Mattias; Sundh, Daniel

2018-05-05

Depression in the elderly is today often treated with selective serotonin reuptake inhibitors (SSRIs) because of their favorable adverse effect profile. However, treatment with SSRIs is associated with increased risk of fractures. Whether this increased risk depends on reduced bone strength or increased fall risk due to reduced physical function is not certain. The aim was therefore to investigate if treatment with SSRIs is associated with impaired bone microstructure, bone density, or physical function in older women. From an ongoing population-based study, 1057 women (77.7 ± 1.5 years) were included. Validated questionnaires were used to assess information regarding medical history, medications, smoking, mental and physical health, and physical activity. Physical function was measured using clinically used tests: timed up and go, walking speed, grip strength, chair stand test, and one leg standing. Bone mineral density (BMD) was measured at the hip and spine with dual-energy X-ray absorptiometry (Hologic Discovery A). Bone geometry and microstructure were measured at the ultradistal and distal (14%) site of radius and tibia using high-resolution peripheral quantitative computed tomography (HR-pQCT; XtremeCT). Treatment with SSRIs was associated with higher BMD at the femoral neck, total hip, and lumbar spine, whereas no associations were found for any HR-pQCT-derived measurements. The use of SSRIs was associated with lower grip strength, walking speed, and fewer chair stand rises. These associations were valid also after adjustments for known risk factors for falls. Treatment with SSRIs was, independently of covariates, associated with worse physical function without any signs of inferior bone geometry and microstructure.

Serotonin induces ecdysteroidogenesis and methyl farnesoate synthesis in the mud crab, Scylla serrata.

Science.gov (United States)

Girish, B P; Swetha, C H; Reddy, P Sreenivasula

2017-09-02

In the current study, we have examined the role of serotonin in regulating the levels of methyl farnesoate and ecdysteroids in the giant mud crab Scylla serrata and validated that serotonin indeed is a reproductive hormone. Administration of serotonin elevated circulatory levels of methyl farnesoate and ecdysteroids in crabs. Since methyl farnesoate and ecdysteroid act through retinoid X receptor (RXR) and ecdysteroid receptor (EcR) respectively and these receptors are involved in the regulation of reproduction in crustaceans, we have determined the mRNA levels of RXR and EcR in hepatopancreas and ovary after serotonin administration. The expression levels of both RXR and EcR increased significantly in the hepatopancreas and ovary of serotonin injected crabs when compared to the controls. In vitro organ culture studies revealed that incubation of Y-orgas and mandibular organ explants in the presence of serotonin resulted in a significant increase in the secretion of ecdysteroids by Y-organs, but without alterations in MF synthesis in mandibular organs. From the above studies it is evident that serotonin stimulates Y organs resulting in increased ecdysteroidogenesis. Though the circulatory levels methyl farnesoate elevated after serotonin administration, organ culture studies revealed serotonin mediated methyl farnesaote synthesis is indirect probably by inhibiting release of mandibular organ inhibiting hormone from eyestalks. Copyright © 2017 Elsevier Inc. All rights reserved.

Novel procedure for genotyping of the human serotonin transporter gene-linked polymorphic region (5-HTTLPR)--a region with a high level of allele diversity

DEFF Research Database (Denmark)

Rasmussen, Henrik B; Werge, Thomas M

2007-01-01

determination. After having developed a 5-HTTLPR genotyping assay, we examined all samples of DNA in two separate rounds of analyses and found complete agreement between the results from these two rounds. CONCLUSION: On the basis of simultaneous analysis of tandem repeat size variation and variation of single......BACKGROUND: The serotonin transporter, the target of a group of antidepressant drugs, is involved in the regulation of the availability and reuptake of serotonin. A variable number of tandem repeats in the promoter region of the serotonin transporter gene, designated 5-HTTLPR, affects...... for detailed genotyping of 5-HTTLPR based upon simultaneous analysis of tandem repeat size variation and single nucleotide variations. METHODS: We elaborated a list of all known 5-HTTLPR alleles to provide an overview of the allele repertoire at this polymorphic locus. Fragments of 5-HTTLPR were PCR...

Neuronal NOS inhibitor 1-(2-trifluoromethylphenyl)-imidazole augment the effects of antidepressants acting via serotonergic system in the forced swimming test in rats.

Science.gov (United States)

Ulak, Güner; Mutlu, Oguz; Akar, Füruzan Yildiz; Komsuoğlu, F Ipek; Tanyeri, Pelin; Erden, B Faruk

2008-10-01

Treatment-resistant depression has necessitated new therapeutic strategies in augmenting the therapeutic actions of currently existing antidepressant drugs. The aim of this study was to investigate the possibility of synergistic interaction between 1-(2-trifluoromethylphenyl)-imidazole (TRIM), a novel neuronal nitric oxide synthase (nNOS) inhibitor and conventional antidepressants of different classes in the forced swimming test (FST) in rats. TRIM decreased the immobility time at 50 mg/kg doses in the FST in rats. Treatment with a behaviourally subeffective dose of TRIM (20 mg/kg) augmented the behavioural effect of tricyclic antidepressant imipramine, selective serotonin re-uptake inhibitor (SSRI) citalopram and fluoxetine or selective serotonin reuptake enhancer tianeptine but failed to augment the antidepressant effect of reboxetine, a noradrenaline re-uptake inhibitor, in this test. Therefore inhibition of NOS augments the effects of antidepressants acting on serotonergic system in the FST. Neither TRIM (10-50 mg/kg) nor other drug treatments affected the locomotor activity of animals. These findings are in agreement with the view that antidepressant effects or augmentation of these effects in the FST may be explained with inhibition of NOS activity and this may be a new approach in offering greater therapeutic efficacy of antidepressants acting via serotonergic system.

Different components of 3H-imipramine binding in rat brain membranes: relation to serotonin uptake sites

International Nuclear Information System (INIS)

Gobbi, M.; Taddei, C.; Mennini, T.

1988-01-01

In the present paper, the authors confirm and extend previous studies showing heterogeneous 3 H-imipramine ( 3 H-IMI) binding sites. Inhibition curves of various drugs (serotonin, imipramine, desmethyl-imipramine, d-fenfluramine, d-norfenfluramine and indalpine, a potent serotonin uptake inhibitor) obtained using 2 nM 3 H-IMI and in presence of 120 mM NaCl, confirmed the presence of at least three 3 H-IMI binding sites: two of these were serotonin-insensitive while the third one was selectively inhibited by serotonin and indalpine with nanomolar affinities. Moreover this last component was found to be selectively modulated by chronic imipramine treatment thus suggesting a close relation to serontonin uptake mechanism. These data indicate that the use of a more selective inhibitors of the serotonin-sensitive component (like indalpine or serotonin itself) to define non specific 3 H-IMI, may be of help in understanding its relation with serotonin uptake system. 22 references, 2 figures, 2 tables

Escitalopram for the management of major depressive disorder: a review of its efficacy, safety, and patient acceptability

Directory of Open Access Journals (Sweden)

Kirino E

2012-12-01

Full Text Available Eiji Kirino1,21Department of Psychiatry, Juntendo University Shizuoka Hospital, Shizuoka, Japan; 2Department of Psychiatry, Juntendo University School of Medicine, Tokyo, JapanAbstract: Escitalopram (escitalopram oxalate; Cipralex®, Lexapro® is a selective serotonin reuptake inhibitor (SSRI used for the treatment of major depressive disorder (MDD and anxiety disorder. This drug exerts a highly selective, potent, and dose-dependent inhibitory effect on the human serotonin transport. By inhibiting the reuptake of serotonin into presynaptic nerve endings, this drug enhances the activity of serotonin in the central nervous system. Escitalopram also has allosteric activity. Moreover, the possibility of interacting with other drugs is considered low. This review covers randomized, controlled studies that enrolled adult patients with MDD to evaluate the efficacy of escitalopram based on the Montgomery–Asberg Depression Rating Scale and the Hamilton Depression Rating Scale. The results showed that escitalopram was superior to placebo, and nearly equal or superior to other SSRIs (eg, citalopram, paroxetine, fluoxetine, sertraline and serotonin-noradrenaline reuptake inhibitors (eg, duloxetine, sustained-release venlafaxine. In addition, with long-term administration, escitalopram has shown a preventive effect on MDD relapse and recurrence. Escitalopram also showed favorable tolerability, and associated adverse events were generally mild and temporary. Discontinuation symptoms were milder with escitalopram than with paroxetine. In view of the patient acceptability of escitalopram, based on both a meta-analysis and a pooled analysis, this drug was more favorable than other new antidepressants. The findings indicate that escitalopram achieved high continuity in antidepressant drug therapy.Keywords: escitalopram, MDD, SSRI, allosteric action, discontinuation symptoms

Use of selective serotonin reuptake inhibitors and risk of re-operation due to post-surgical bleeding in breast cancer patients: a Danish population-based cohort study

Directory of Open Access Journals (Sweden)

Lash Timothy L

2010-01-01

Full Text Available Abstract Background Selective serotonin reuptake inhibitors (SSRI decrease platelet-function, which suggests that SSRI use may increase the risk of post-surgical bleeding. Few studies have investigated this potential association. Methods We conducted a population-based study of the risk of re-operation due to post-surgical bleeding within two weeks of primary surgery among Danish women with primary breast cancer. Patients were categorised according to their use of SSRI: never users, current users (SSRI prescription within 30 days of initial breast cancer surgery, and former users (SSRI prescription more than 30 days before initial breast cancer surgery. We calculated the risk of re-operation due to post-surgical bleeding within 14 days of initial surgery, and the relative risk (RR of re-operation comparing SSRI users with never users of SSRI adjusting for potential confounders. Results 389 of 14,464 women (2.7% were re-operated. 1592 (11% had a history of SSRI use. Risk of re-operation was 2.6% among never users, 7.0% among current SSRI users, and 2.7% among former users. Current users thus had an increased risk of re-operation due to post-operative bleeding (adjusted relative risk = 2.3; 95% confidence interval (CI = 1.4, 3.9 compared with never users. There was no increased risk of re-operation associated with former use of SSRI (RR = 0.93, 95% CI = 0.66, 1.3. Conclusions Current use of SSRI is associated with an increased risk of re-operation due to bleeding after surgery for breast cancer.

Discovery of Indazoles as Potent, Orally Active Dual Neurokinin 1 Receptor Antagonists and Serotonin Transporter Inhibitors for the Treatment of Depression.

Science.gov (United States)

Degnan, Andrew P; Tora, George O; Huang, Hong; Conlon, David A; Davis, Carl D; Hanumegowda, Umesh M; Hou, Xiaoping; Hsiao, Yi; Hu, Joanna; Krause, Rudolph; Li, Yu-Wen; Newton, Amy E; Pieschl, Rick L; Raybon, Joseph; Rosner, Thorsten; Sun, Jung-Hui; Taber, Matthew T; Taylor, Sarah J; Wong, Michael K; Zhang, Huiping; Lodge, Nicholas J; Bronson, Joanne J; Macor, John E; Gillman, Kevin W

2016-12-21

Combination studies of neurokinin 1 (NK1) receptor antagonists and serotonin-selective reuptake inhibitors (SSRIs) have shown promise in preclinical models of depression. Such a combination may offer important advantages over the current standard of care. Herein we describe the discovery and optimization of an indazole-based chemotype to provide a series of potent dual NK1 receptor antagonists/serotonin transporter (SERT) inhibitors to overcome issues of ion channel blockade. This effort culminated in the identification of compound 9, an analogue that demonstrated favorable oral bioavailability, excellent brain uptake, and robust in vivo efficacy in a validated depression model. Over the course of this work, a novel heterocycle-directed asymmetric hydrogenation was developed to facilitate installation of the key stereogenic center.

Serotonin induces peripheral antinociception via the opioidergic system.

Science.gov (United States)

Diniz, Danielle Aguiar; Petrocchi, Júlia Alvarenga; Navarro, Larissa Caldeira; Souza, Tâmara Cristina; Castor, Marina Gomes Miranda E; Duarte, Igor Dimitri Gama; Romero, Thiago Roberto Lima

2018-01-01

Studies conducted since 1969 have shown that the release of serotonin (5-HT) in the dorsal horn of the spinal cord contributes to opioid analgesia. In the present study, the participation of the opioidergic system in antinociceptive effect serotonin at the peripheral level was examined. The paw pressure test was used with mice (Swiss, males from 35 g) which had increased pain sensitivity by intraplantar injection of PGE 2 (2 μg). Serotonin (250 ng), administered locally to the right paw of animals, produces antinociception in this model. The selective antagonists for mu, delta and kappa opioid receptors, clocinnamox clocinnamox (40 μg), naltrindole (60 μg) and nor-binaltorfimina (200 μg), respectively, inhibited the antinociceptive effect induced by serotonin. Additionally, bestatin (400 μg), an inhibitor of enkephalinases that degrade peptides opioids, enhanced the antinociceptive effect induced by serotonin (low dose of 62.5 ng). These results suggest that serotonin possibly induce peripheral antinociception through the release of endogenous opioid peptides, possible from immune cells or keratinocytes. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Effect of mirtazapine versus selective serotonin reuptake inhibitors on benzodiazepine use in patients with major depressive disorder: a pragmatic, multicenter, open-label, randomized, active-controlled, 24-week trial.

Science.gov (United States)

Hashimoto, Tasuku; Shiina, Akihiro; Hasegawa, Tadashi; Kimura, Hiroshi; Oda, Yasunori; Niitsu, Tomihisa; Ishikawa, Masatomo; Tachibana, Masumi; Muneoka, Katsumasa; Matsuki, Satoshi; Nakazato, Michiko; Iyo, Masaomi

2016-01-01

This study aimed to evaluate whether selecting mirtazapine as the first choice for current depressive episode instead of selective serotonin reuptake inhibitors (SSRIs) reduces benzodiazepine use in patients with major depressive disorder (MDD). We concurrently examined the relationship between clinical responses and serum mature brain-derived neurotrophic factor (BDNF) and its precursor, proBDNF. We conducted an open-label randomized trial in routine psychiatric practice settings. Seventy-seven MDD outpatients were randomly assigned to the mirtazapine or predetermined SSRIs groups, and investigators arbitrarily selected sertraline or paroxetine. The primary outcome was the proportion of benzodiazepine users at weeks 6, 12, and 24 between the groups. We defined patients showing a ≥50 % reduction in Hamilton depression rating scale (HDRS) scores from baseline as responders. Blood samples were collected at baseline, weeks 6, 12, and 24. Sixty-five patients prescribed benzodiazepines from prescription day 1 were analyzed for the primary outcome. The percentage of benzodiazepine users was significantly lower in the mirtazapine than in the SSRIs group at weeks 6, 12, and 24 (21.4 vs. 81.8 %; 11.1 vs. 85.7 %, both P  depressive episodes may reduce benzodiazepine use in patients with MDD. Trial registration UMIN000004144. Registered 2nd September 2010. The date of enrolment of the first participant to the trial was 24th August 2010. This study was retrospectively registered 9 days after the first participant was enrolled.

5-HT1A and 5-HT7 receptor crosstalk in the regulation of emotional memory: implications for effects of selective serotonin reuptake inhibitors.

Science.gov (United States)

Eriksson, Therese M; Holst, Sarah; Stan, Tiberiu L; Hager, Torben; Sjögren, Benita; Ogren, Sven Öve; Svenningsson, Per; Stiedl, Oliver

2012-11-01

This study utilized pharmacological manipulations to analyze the role of direct and indirect activation of 5-HT(7) receptors (5-HT(7)Rs) in passive avoidance learning by assessing emotional memory in male C57BL/6J mice. Additionally, 5-HT(7)R binding affinity and 5-HT(7)R-mediated protein phosphorylation of downstream signaling targets were determined. Elevation of 5-HT by the selective serotonin reuptake inhibitor (SSRI) fluoxetine had no effect by itself, but facilitated emotional memory performance when combined with the 5-HT(1A)R antagonist NAD-299. This facilitation was blocked by the selective 5-HT(7)R antagonist SB269970, revealing excitatory effects of the SSRI via 5-HT(7)Rs. The enhanced memory retention by NAD-299 was blocked by SB269970, indicating that reduced activation of 5-HT(1A)Rs results in enhanced 5-HT stimulation of 5-HT(7)Rs. The putative 5-HT(7)R agonists LP-44 when administered systemically and AS19 when administered both systemically and into the dorsal hippocampus failed to facilitate memory. This finding is consistent with the low efficacy of LP-44 and AS19 to stimulate protein phosphorylation of 5-HT(7)R-activated signaling cascades. In contrast, increasing doses of the dual 5-HT(1A)R/5-HT(7)R agonist 8-OH-DPAT impaired memory, while co-administration with NAD-299 facilitated of emotional memory in a dose-dependent manner. This facilitation was blocked by SB269970 indicating 5-HT(7)R activation by 8-OH-DPAT. Dorsohippocampal infusion of 8-OH-DPAT impaired passive avoidance retention through hippocampal 5-HT(1A)R activation, while 5-HT(7)Rs appear to facilitate memory processes in a broader cortico-limbic network and not the hippocampus alone. Copyright © 2012 Elsevier Ltd. All rights reserved.

Antenatal exposure to the selective serotonin reuptake inhibitor fluoxetine leads to postnatal metabolic and endocrine changes associated with type 2 diabetes in Wistar rats

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De Long, Nicole E.; Barry, Eric J. [Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON L8S 4K1 (Canada); Pinelli, Christopher; Wood, Geoffrey A. [Department of Pathobiology, University of Guelph, Guelph, ON N1G 2W1 (Canada); Hardy, Daniel B. [Department of Obstetrics and Gynecology, Physiology and Pharmacology, University of Western, London, ON N6A 3K6 (Canada); Morrison, Katherine M. [Department of Pediatrics, McMaster University, Hamilton, ON L8S 4K1 (Canada); Taylor, Valerie H. [Department of Psychiatry, University of Toronto, Toronto, ON M5S 1A1 (Canada); Gerstein, Hertzel C. [Department of Medicine, McMaster University, Hamilton, ON L8S 4K1 (Canada); Holloway, Alison C., E-mail: hollow@mcmaster.ca [Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON L8S 4K1 (Canada)

2015-05-15

Hypothesis: 10–15% of women take antidepressant medications during pregnancy. A recent clinical study reported that the use of selective serotonin reuptake inhibitor antidepressants during pregnancy is linked with an increased risk of postnatal obesity. While obesity is often associated with fatty liver, dyslipidemia and inflammation, to date, the effects of perinatal exposure to SSRIs on these outcomes are unknown. Methods: Female nulliparous Wistar rats were given vehicle (N = 15) or fluoxetine hydrochloride (FLX 10 mg/kg/d; N = 15) orally for 2 weeks prior to mating until weaning. We assessed glucometabolic changes and hepatic pathophysiology in the offspring. Results: Fluoxetine exposed offspring demonstrated altered glucose homeostasis without any alterations to beta cell mass. FLX-exposed offspring had a significant increase in the number of offspring with mild to moderate NASH and dyslipidemia. There was also increased inflammation of the liver in FLX-exposed offspring; males had significant elevations in TNFα, IL6 and monocyte chemoattractant protein 1 (MCP1), while female offspring had higher expression of TNFα, and increased macrophage infiltration (MCP1). Limitations: This is an animal study. Further research examining the metabolic outcomes of children exposed to antidepressants in utero are required, given the increase in childhood obesity and psychiatric medication use during pregnancy. Conclusion: These data demonstrate that fetal and neonatal exposure to FLX results in evidence of increased adiposity, fatty liver and abnormal glycemic control. Since these are all hallmarks of the metabolic syndrome, this raises concerns regarding the long term metabolic sequelae of fetal exposure to SSRIs in human populations. - Highlights: • Antenatal exposure to fluoxetine results in postnatal adiposity in the offspring. • Offspring exposed to fluoxetine have abnormal glycemic control in adulthood. • Maternal exposure to fluoxetine causes fatty liver in

Antenatal exposure to the selective serotonin reuptake inhibitor fluoxetine leads to postnatal metabolic and endocrine changes associated with type 2 diabetes in Wistar rats

International Nuclear Information System (INIS)

De Long, Nicole E.; Barry, Eric J.; Pinelli, Christopher; Wood, Geoffrey A.; Hardy, Daniel B.; Morrison, Katherine M.; Taylor, Valerie H.; Gerstein, Hertzel C.; Holloway, Alison C.

2015-01-01

Hypothesis: 10–15% of women take antidepressant medications during pregnancy. A recent clinical study reported that the use of selective serotonin reuptake inhibitor antidepressants during pregnancy is linked with an increased risk of postnatal obesity. While obesity is often associated with fatty liver, dyslipidemia and inflammation, to date, the effects of perinatal exposure to SSRIs on these outcomes are unknown. Methods: Female nulliparous Wistar rats were given vehicle (N = 15) or fluoxetine hydrochloride (FLX 10 mg/kg/d; N = 15) orally for 2 weeks prior to mating until weaning. We assessed glucometabolic changes and hepatic pathophysiology in the offspring. Results: Fluoxetine exposed offspring demonstrated altered glucose homeostasis without any alterations to beta cell mass. FLX-exposed offspring had a significant increase in the number of offspring with mild to moderate NASH and dyslipidemia. There was also increased inflammation of the liver in FLX-exposed offspring; males had significant elevations in TNFα, IL6 and monocyte chemoattractant protein 1 (MCP1), while female offspring had higher expression of TNFα, and increased macrophage infiltration (MCP1). Limitations: This is an animal study. Further research examining the metabolic outcomes of children exposed to antidepressants in utero are required, given the increase in childhood obesity and psychiatric medication use during pregnancy. Conclusion: These data demonstrate that fetal and neonatal exposure to FLX results in evidence of increased adiposity, fatty liver and abnormal glycemic control. Since these are all hallmarks of the metabolic syndrome, this raises concerns regarding the long term metabolic sequelae of fetal exposure to SSRIs in human populations. - Highlights: • Antenatal exposure to fluoxetine results in postnatal adiposity in the offspring. • Offspring exposed to fluoxetine have abnormal glycemic control in adulthood. • Maternal exposure to fluoxetine causes fatty liver in

A double blind comparison of venlafaxine and paroxetine in obsessive-compulsive disorder

NARCIS (Netherlands)

Denys, Damiaan; van der Wee, Nic; van Megen, Harold J. G. M.; Westenberg, Herman G. M.

2003-01-01

SUMMARY: While the usefulness of clomipramine and selective serotonin reuptake inhibitors (SSRIs) in obsessive-compulsive disorder (OCD) has been established, the efficacy of serotonin-norepinephrine reuptake inhibitors remains to be determined. This report describes the first randomized

Serotonin neurons in the dorsal raphe mediate the anticataplectic action of orexin neurons by reducing amygdala activity.

Science.gov (United States)

Hasegawa, Emi; Maejima, Takashi; Yoshida, Takayuki; Masseck, Olivia A; Herlitze, Stefan; Yoshioka, Mitsuhiro; Sakurai, Takeshi; Mieda, Michihiro

2017-04-25

Narcolepsy is a sleep disorder caused by the loss of orexin (hypocretin)-producing neurons and marked by excessive daytime sleepiness and a sudden weakening of muscle tone, or cataplexy, often triggered by strong emotions. In a mouse model for narcolepsy, we previously demonstrated that serotonin neurons of the dorsal raphe nucleus (DRN) mediate the suppression of cataplexy-like episodes (CLEs) by orexin neurons. Using an optogenetic tool, in this paper we show that the acute activation of DRN serotonin neuron terminals in the amygdala, but not in nuclei involved in regulating rapid eye-movement sleep and atonia, suppressed CLEs. Not only did stimulating serotonin nerve terminals reduce amygdala activity, but the chemogenetic inhibition of the amygdala using designer receptors exclusively activated by designer drugs also drastically decreased CLEs, whereas chemogenetic activation increased them. Moreover, the optogenetic inhibition of serotonin nerve terminals in the amygdala blocked the anticataplectic effects of orexin signaling in DRN serotonin neurons. Taken together, the results suggest that DRN serotonin neurons, as a downstream target of orexin neurons, inhibit cataplexy by reducing the activity of amygdala as a center for emotional processing.

FOXO1 orchestrates the bone-suppressing function of gut-derived serotonin

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Kode, Aruna; Mosialou, Ioanna; Silva, Barbara C.; Rached, Marie-Therese; Zhou, Bin; Wang, Ji; Townes, Tim M.; Hen, Rene; DePinho, Ronald A.; Guo, X. Edward; Kousteni, Stavroula

2012-01-01

Serotonin is a critical regulator of bone mass, fulfilling different functions depending on its site of synthesis. Brain-derived serotonin promotes osteoblast proliferation, whereas duodenal-derived serotonin suppresses it. To understand the molecular mechanisms of duodenal-derived serotonin action on osteoblasts, we explored its transcriptional mediation in mice. We found that the transcription factor FOXO1 is a crucial determinant of the effects of duodenum-derived serotonin on bone formation We identified two key FOXO1 complexes in osteoblasts, one with the transcription factor cAMP-responsive element–binding protein 1 (CREB) and another with activating transcription factor 4 (ATF4). Under normal levels of circulating serotonin, the proliferative activity of FOXO1 was promoted by a balance between its interaction with CREB and ATF4. However, high circulating serotonin levels prevented the association of FOXO1 with CREB, resulting in suppressed osteoblast proliferation. These observations identify FOXO1 as the molecular node of an intricate transcriptional machinery that confers the signal of duodenal-derived serotonin to inhibit bone formation. PMID:22945629

What is the difference between dependence and withdrawal reactions?

DEFF Research Database (Denmark)

Nielsen, Margrethe; Hansen, Ebba Holme; Gøtzsche, Peter C

2012-01-01

To explore the rationale for claiming that benzodiazepines cause dependence while selective serotonin re-uptake inhibitors (SSRIs) do not.......To explore the rationale for claiming that benzodiazepines cause dependence while selective serotonin re-uptake inhibitors (SSRIs) do not....

Animal experiment studies on biological and chemical radiation protection - the combined effects of serotonin and erythropoletin

International Nuclear Information System (INIS)

Sasse, U.

1975-01-01

The influence of a prophylactic combination treatment with serotonin and erythropoietin on the inhibited erythropoiesis of whole-body irradiated mice (500 R) was studied. Both erythropoietin and serotonin turned out to compensate the radiation-induced inhibition of the formation rate for erythrocytes to a small extent. However, only the enhancement of erythropoiesis due to serotonin indicated significant values. Yet the combined application of the named substances yielded a distinct and significant effect in radiation protection which even exceeded the simple addition of the protective effect yielded by serotonin and erythropoietin alone. But despite of this considerable success the radiation damage in the erythropoietic system was not even half compensated for. (orig./MG) [de

Metabolomics Approach Reveals Integrated Metabolic Network Associated with Serotonin Deficiency

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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.

The role of genetic factors in predicting results of obesity treatment with sibutramine – serotonin-norepinephrine reuptake inhibitor

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Marina Galieva

2016-12-01

Full Text Available Aim. To study the influence of SERT and GNB3 gene polymorphisms on the results of the treatment of obesity by serotonin-norepinephrine reuptake inhibitors. Methods. Patients who didn’t achieve significant weight loss in 3 month period during PrimaVera Study were selected for the genetic evaluation and compared with the group of “effective treatment”. The study included 66 patients (57 females and 9 males, mean age 39.29 ± 12.64 years, who received Reduxin (sibutramine + MCC at the dose of 10 mg. Term follow-up was 3 months. Clinical examination and determination of biochemical parameters was performed at baseline and at the end of the observation period. In order to assess the type of eating behavior and identify hidden depressions a validated questionnaire was used (questionnaire "The types of eating disorders» (DEBQ, Beck Depression Scale. Also conducted a genetic study to assess SERT and GBN3 gene polymorphisms. Results. In the second group presence of S-allele SERT-gene was significantly associated with higher rates of external type of eating behavior. A statistically significant correlation between the genotype or allele of either body weight, rates of blood pressure, heart rate and cholesterol have not been found. In the first group there was a statistically significant association of S-allele carrier with less weight loss -2.8 kg (compared to l-allele and higher rates at baseline glucose 5.38 ± 0.63 mmol / l (compared to L-allele of -3.28 kg and 5.04 ± 0.91 mmol / l. In the study of GBN3 polymorphism in the second group among CC genotype carriers there were higher levels of systolic blood pressure (SBP before treatment (129.27 ± 9.16 mmHg, SBP and diastolic blood pressure after 3 months of treatment (127.36 ± 8.16 and 78.36 ± 4.3 mmHg compared with CT genotype (117.27 ± 12.5; 115.45 ± 10.6; 72.91 ± 6.0 mm Hg, respectively (p <0.05. Also among the carriers of C-allele there were more severe manifestations of

The neuropharmacology of serotonin and noradrenaline in depression.

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Nutt, David J

2002-06-01

Several classes of antidepressant drug exist, divided into three broad families, the monoamine reuptake inhibitors, the monoamine oxidase inhibitors and the monoamine receptor antagonists. All these drugs have a common pharmacological effect, to raise the synaptic concentrations of noradrenaline and serotonin. Although different drugs have different relative selectivity for noradrenaline and serotonin systems, these two neurotransmitter pathways work in parallel and in a coherent manner to produce the same final antidepressant response. The lag-time in the onset of action of antidepressants can be explained by the activation of inhibitory autoreceptors on serotonergic and noradrenergic neurones which initially attenuate the effects of antidepressants on synaptic transmitter levels. Over time, these autoreceptors desensitize, allowing the emergence of an overt antidepressant response. This theory has led to the proposition that antagonists at these autoreceptors such as pindolol may be useful adjuncts to antidepressant treatment, in order to hasten the appearance of a clinical response. Evidence for the clinical validity of this idea remains equivocal, however. The use of central monoamine depletion studies has demonstrated that it is elevated synaptic monoamine levels themselves, rather than some downstream postsynaptic changes in, for example, receptor sensitivity, that are responsible for the therapeutic effect of antidepressant drugs. Taken together, the data collected over the last 40 years have allowed the emergence of a unified monoamine hypothesis of antidepressant drug action.

Dopamine/noradrenaline reuptake inhibition in women improves endurance exercise performance in the heat.

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Cordery, P; Peirce, N; Maughan, R J; Watson, P

2017-11-01

Catecholamine reuptake inhibition improves the performance of male volunteers exercising in warm conditions, but sex differences in thermoregulation, circulating hormones, and central neurotransmission may alter this response. With local ethics committee approval, nine physically active women (mean ± SD age 21 ± 2 years; height 1.68 ± 0.08 m; body mass 64.1 ± 6.0 kg; VO 2peak 51 ± 7 mL/kg/min) were recruited to examine the effect of pre-exercise administration of Bupropion (BUP; 4 × 150 mg) on prolonged exercise performance in a warm environment. Participants completed a VO 2peak test, two familiarization trials, and two randomized, double-blind experimental trials. All trials took place during the first 10 days of the follicular phase of the menstrual cycle. Participants cycled for 1 h at 60% VO 2peak followed by a 30-min performance test. Total work done was greater during the BUP trial (291 ± 48 kJ) than the placebo trial (269 ± 46 kJ, P = 0.042, d = 0.497). At the end of the performance test, core temperature was higher on the BUP trial (39.5 ± 0.4 °C) than on the placebo trial (39.2 ± 0.6 °C, P = 0.021; d = 0.588), as was heart rate (185 ± 9 vs 179 ± 13, P = 0.043; d = 0.537). The results indicate that during the follicular phase of the menstrual cycle, an acute dosing protocol of BUP can improve self-regulated performance in warm conditions. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Inhibitory effect of fluvoxamine on β-casein expression via a serotonin-independent mechanism in human mammary epithelial cells.

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Chiba, Takeshi; Maeda, Tomoji; Kimura, Soichiro; Morimoto, Yasunori; Sanbe, Atsushi; Ueda, Hideo; Kudo, Kenzo

2015-11-05

Selective serotonin reuptake inhibitors (SSRIs) are widely used as a first-line therapy in postpartum depression. The objective of this study was to determine the mechanism underlying the inhibitory effects of the SSRI, fluvoxamine, on β-casein expression, an indicator of lactation, in MCF-12A human mammary epithelial cells. Expression levels of serotonin (5-hydroxytryptamine; 5-HT) transporter, an SSRI target protein, and tryptophan hydroxylase 1, a rate-limiting enzyme in 5-HT biosynthesis, were increased in MCF-12A cells by prolactin treatment. Treatment with 1 μM fluvoxamine for 72 h significantly decreased protein levels of β-casein and phosphorylated signal transducer and activator transcription 5 (pSTAT5). Extracellular 5-HT levels were significantly increased after exposure to 1 μM fluvoxamine, in comparison with those of untreated and vehicle-treated cells; however, extracellular 5-HT had little effect on the decrease in β-casein expression. Expression of glucose-related protein 78/binding immunoglobulin protein, a regulator of endoplasmic reticulum (ER) stress, was significantly increased after treatment with 1 μM fluvoxamine for 48 h. Exposure to tunicamycin, an inducer of ER stress, also decreased expression of β-casein and pSTAT5 in a manner similar to fluvoxamine. Our results indicate that fluvoxamine suppresses β-casein expression in MCF-12A cells via inhibition of STAT5 phosphorylation caused by induction of ER stress. Further studies are required to confirm the effect of fluvoxamine on the function of mammary epithelial cells. Copyright © 2015 Elsevier B.V. All rights reserved.

Fluoxetine Induces Proliferation and Inhibits Differentiation of Hypothalamic Neuroprogenitor Cells In Vitro

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Sousa-Ferreira, Lígia; Aveleira, Célia; Botelho, Mariana; Álvaro, Ana Rita; Pereira de Almeida, Luís; Cavadas, Cláudia

2014-01-01

A significant number of children undergo maternal exposure to antidepressants and they often present low birth weight. Therefore, it is important to understand how selective serotonin reuptake inhibitors (SSRIs) affect the development of the hypothalamus, the key center for metabolism regulation. In this study we investigated the proliferative actions of fluoxetine in fetal hypothalamic neuroprogenitor cells and demonstrate that fluoxetine induces the proliferation of these cells, as shown by increased neurospheres size and number of proliferative cells (Ki-67+ cells). Moreover, fluoxetine inhibits the differentiation of hypothalamic neuroprogenitor cells, as demonstrated by decreased number of mature neurons (Neu-N+ cells) and increased number of undifferentiated cells (SOX-2+ cells). Additionally, fluoxetine-induced proliferation and maintenance of hypothalamic neuroprogenitor cells leads to changes in the mRNA levels of appetite regulator neuropeptides, including Neuropeptide Y (NPY) and Cocaine-and-Amphetamine-Regulated-Transcript (CART). This study provides the first evidence that SSRIs affect the development of hypothalamic neuroprogenitor cells in vitro with consequent alterations on appetite neuropeptides. PMID:24598761

Differences in serotonin transporter binding affinity in patients with major depressive disorder and night eating syndrome.

Science.gov (United States)

Lundgren, J D; Amsterdam, J; Newberg, A; Allison, K C; Wintering, N; Stunkard, A J

2009-03-01

We examined serotonin transporter (SERT) binding affinity using single photon emission computed tomography (SPECT) in patients with major depressive disorder (MDD) and night eating syndrome (NES). There are similarities between MDD and NES in affective symptoms, appetite disturbance, nighttime awakenings, and, particularly, response to selective serotonin reuptake inhibitors (SSRIs). Six non-depressed patients with NES and seven patients with MDD underwent SPECT brain imaging with 123I-ADAM, a radiopharmaceutical agent selective for SERT sites. Uptake ratios of 123I-ADAM SERT binding were obtained for the midbrain, basal ganglia, and temporal lobe regions compared to the cerebellum reference region. Patients with NES had significantly greater SERT uptake ratios (effect size range 0.64-0.84) in the midbrain, right temporal lobe, and left temporal lobe regions than those with MDD whom we had previously studied. Pathophysiological differences in SERT uptake between patients with NES and MDD suggest these are distinct clinical syndromes.

Increasing the Risk of Spontaneous Abortion and Major Malformations in Newborns Following Use of Serotonin Reuptake Inhibitors during Pregnancy: a Systematic Review and Updated Meta-Analysis

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Mohammad Abdollahi

2012-11-01

Full Text Available Selective serotonin reuptake inhibitors (SSRIs are the most frequently used antidepressants during pregnancy. There are conflicting results about their influence on pregnancy outcomes.The goal of this study was to update our previous meta-analysis about pregnancy outcomes following exposure to SSRIs. For this purpose, all relevant databases were searched from 1990 to March 2012 for studies investigating the pregnancy outcomes following exposure to any therapeutic dosage of any SSRI (fluoxetine, paroxetine, citalopram, escitalopram, sertraline, fluvoxamine during pregnancy. Types of outcome investigated were spontaneousabortion, major malformations, cardiovascular malformations, and minor malformations. A total of 25 studies met our criteria and were included in the meta-analysis. The odds ratio (OD values are 1.87 (95% CI: 1.5 to 2.33, P< 0.0001 for spontaneous abortion, 1.272 (95%CI: 1.098 to 1.474, P = 0.0014 for major malformations, 1.192 (95% CI: 0.39 to 3.644, P=0.7578 for cardiovascular malformations, and 1.36 (95% CI: 0.61 to 3.04, P= 0.4498 for minor malformations. The results demonstrated that SSRIs increase the risk of spontaneousabortion and major malformations during pregnancy while they don’t increase the risk of cardiovascular malformations and minor malformations. Our previous meta-analysis only showed an increase in the risk of spontaneous abortion following the use of SSRIs duringpregnancy. This might be due to increase in the number of studies included or addition of two new SSRIs (citalopram and escitalopram. The message to researchers is to try considering SSRIs individually during pregnancy to reduce heterogeneity, although all are aware ofinevitable limitations to study on pregnant mothers.

Substrate and Inhibitor-Specific Conformational Changes in the Human Serotonin Transporter Revealed by Voltage-Clamp Fluorometry

DEFF Research Database (Denmark)

Söderhielm, Pella C; Andersen, Jacob; Munro, Lachlan

2015-01-01

of TM6, Ala419 in the interface between TM8 and extracellular loop (EL) 4, and Leu481 in EL5. The reporter positions were used for time-resolved measurement of conformational changes during 5-HT transport and binding of cocaine and the selective serotonin reuptake inhibitors fluoxetine and escitalopram...... changes overall, which included movements within or around TM1b, EL4, and EL5. Taken together, our data lead us to suggest that competitive inhibitors stabilize hSERT in a state that is different from the apo outward-open conformation as well as inward-facing conformations....

Estrous cycle modulation of extracellular serotonin in mediobasal hypothalamus: role of the serotonin transporter and terminal autoreceptors.

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Maswood, S; Truitt, W; Hotema, M; Caldarola-Pastuszka, M; Uphouse, L

1999-06-12

In vivo microdialysis was used to examine extracellular serotonin (5-HT) in the mediobasal hypothalamus (MBH) of male and female Fischer (CDF-344) rats. Females from the stages of diestrus, proestrus, and estrus were used. Additionally, ovariectomized rats, primed subcutaneously (s.c.) with estradiol benzoate or estradiol benzoate plus progesterone were examined. Extracellular 5-HT in the MBH varied with stage of the estrous cycle and with the light/dark cycle. Proestrous females had the highest microdialysate concentrations of 5-HT during the light portion of the light/dark cycle and lowest concentrations during the dark portion of the cycle. Diestrous females had the highest levels during the dark portion of the cycle, while males and estrous females showed little change between light and dark portions of the cycle. In ovariectomized rats, there was no effect of 2.5 microg or 25 microg estradiol benzoate (s.c.) on extracellular 5-HT; but the addition of 500 microg progesterone, 48 h after estrogen priming, reduced microdialysate 5-HT near the threshold for detection. In intact females and in males, reverse perfusion with 3 microM fluoxetine, a selective serotonin reuptake inhibitor (SSRI), or 2 microM methiothepin, a 5-HT receptor antagonist, increased microdialysate concentrations of 5-HT. Estrous females and males showed nearly a 4-fold increase in microdialysate 5-HT in response to fluoxetine while smaller responses were seen in diestrous and proestrous rats. In contrast, proestrous rats showed the largest response to methiothepin. Estrous females showed a delayed response to methiothepin, but there was no methiothepin-induced increase in extracellular 5-HT in males. These findings are discussed in reference to the suggestion that extracellular 5-HT in the MBH is regulated in a manner that is gender and estrous cycle dependent. The 5-HT terminal autoreceptor may exert a greater role in proestrous females; the serotonin transporter appears to play a more active

Genetic predictors of response to serotonergic and noradrenergic antidepressants in major depressive disorder: a genome-wide analysis of individual-level data and a meta-analysis.

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Tansey, Katherine E; Guipponi, Michel; Perroud, Nader; Bondolfi, Guido; Domenici, Enrico; Evans, David; Hall, Stephanie K; Hauser, Joanna; Henigsberg, Neven; Hu, Xiaolan; Jerman, Borut; Maier, Wolfgang; Mors, Ole; O'Donovan, Michael; Peters, Tim J; Placentino, Anna; Rietschel, Marcella; Souery, Daniel; Aitchison, Katherine J; Craig, Ian; Farmer, Anne; Wendland, Jens R; Malafosse, Alain; Holmans, Peter; Lewis, Glyn; Lewis, Cathryn M; Stensbøl, Tine Bryan; Kapur, Shitij; McGuffin, Peter; Uher, Rudolf

2012-01-01

It has been suggested that outcomes of antidepressant treatment for major depressive disorder could be significantly improved if treatment choice is informed by genetic data. This study aims to test the hypothesis that common genetic variants can predict response to antidepressants in a clinically meaningful way. The NEWMEDS consortium, an academia-industry partnership, assembled a database of over 2,000 European-ancestry individuals with major depressive disorder, prospectively measured treatment outcomes with serotonin reuptake inhibiting or noradrenaline reuptake inhibiting antidepressants and available genetic samples from five studies (three randomized controlled trials, one part-randomized controlled trial, and one treatment cohort study). After quality control, a dataset of 1,790 individuals with high-quality genome-wide genotyping provided adequate power to test the hypotheses that antidepressant response or a clinically significant differential response to the two classes of antidepressants could be predicted from a single common genetic polymorphism. None of the more than half million genetic markers significantly predicted response to antidepressants overall, serotonin reuptake inhibitors, or noradrenaline reuptake inhibitors, or differential response to the two types of antidepressants (genome-wide significance panalysis of NEWMEDS and another large sample (STAR*D), with 2,897 individuals in total. Polygenic scoring found no convergence among multiple associations in NEWMEDS and STAR*D. No single common genetic variant was associated with antidepressant response at a clinically relevant level in a European-ancestry cohort. Effects specific to particular antidepressant drugs could not be investigated in the current study. Please see later in the article for the Editors' Summary.

Improving response inhibition systems in frontotemporal dementia with citalopram.

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Hughes, Laura E; Rittman, Timothy; Regenthal, Ralf; Robbins, Trevor W; Rowe, James B

2015-07-01

Disinhibition is a cardinal feature of the behavioural variant of frontotemporal dementia, presenting as impulsive and impetuous behaviours that are often difficult to manage. The options for symptomatic treatments are limited, but a potential target for therapy is the restoration of serotonergic function, which is both deficient in behavioural variant frontotemporal dementia and closely associated with inhibitory control. Based on preclinical studies and psychopharmacological interventions in other disorders, we predicted that inhibition would be associated with the right inferior frontal gyrus and dependent on serotonin. Using magnetoencephalography and electroencephalography of a Go-NoGo paradigm, we investigated the neural basis of behavioural disinhibition in behavioural variant frontotemporal dementia and the effect of selective serotonin reuptake inhibition on the neural systems for response inhibition. In a randomized double-blinded placebo-controlled crossover design study, 12 patients received either a single 30 mg dose of citalopram or placebo. Twenty age-matched healthy controls underwent the same magnetoencephalography/electroencephalography protocol on one session without citalopram, providing normative data for this task. In the control group, successful NoGo trials evoked two established indices of successful response inhibition: the NoGo-N2 and NoGo-P3. Both of these components were significantly attenuated by behavioural variant frontotemporal dementia. Cortical sources associated with successful inhibition in control subjects were identified in the right inferior frontal gyrus and anterior temporal lobe, which have been strongly associated with behavioural inhibition in imaging and lesion studies. These sources were impaired by behavioural variant frontotemporal dementia. Critically, citalopram enhanced the NoGo-P3 signal in patients, relative to placebo treatment, and increased the evoked response in the right inferior frontal gyrus. Voxel

Serotonin mediation of early memory formation via 5HT2B receptor-induced glycogenolysis in the day-old chick

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Marie Elizabeth Gibbs

2014-04-01

Full Text Available Investigation of the effects of serotonin on memory formation in the chick revealed an action on at least two 5HT receptors. Serotonin injected intracerebrally produced a biphasic effect on memory consolidation with enhancement at low doses and inhibition at higher doses. The non-selective 5HT receptor antagonist methiothepin and the selective 5HT2B/C receptor antagonist SB221284 both inhibited memory, suggesting actions of serotonin on at least 2 different receptor subtypes. The 5HT2B/C and astrocyte-specific 5-HT receptor agonists, fluoxetine and paroxetine, enhanced memory and the effect was attributed to glycogenolysis. Inhibition of glycogenolysis with a low dose of DAB prevented both serotonin and fluoxetine from enhancing memory during short-term memory but not during intermediate memory. The role of serotonin on the 5HT2B/C receptor appears to involve glycogen breakdown in astrocytes during short-term memory, whereas other published evidence attributes the second period of glycogenolysis to noradrenaline.

The effects of the adjunctive bupropion on male sexual dysfunction induced by a selective serotonin reuptake inhibitor: a double-blind placebo-controlled and randomized study.

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Safarinejad, Mohammad Reza

2010-09-01

To determine the safety and efficacy of adjunctive bupropion sustained-release (SR) on male sexual dysfunction (SD) induced by a selective serotonin reuptake inhibitor (SSRI), as SD is a common side-effect of SSRIs and the most effective treatments have yet to be determined. The randomized sample consisted of 234 euthymic men who were receiving some type of SSRI. The men were randomly assigned to bupropion SR (150 mg twice daily, 117) or placebo (twice daily, 117) for 12 weeks. Efficacy was evaluated using the Clinical Global Impression-Sexual Function (CGI-SF; the primary outcome measure), the International Index of Erectile Function (IIEF), Arizona Sexual Experience Scale (ASEX), and Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) (secondary outcome measures). Participants were followed biweekly during study period. After 12 weeks of treatment, the mean (sd) scores for CGI-SF were significantly lower, i.e. better, in patients on bupropion SR, at 2.4 (1.2), than in the placebo group, at 3.9 (1.1) (P= 0.01). Men who received bupropion had a significant increase in the total IIEF score (54.4% vs 1.2%; P= 0.003), and in the five different domains of the IIEF. Total ASEX scores were significantly lower, i.e. better, among men who received bupropion than placebo, at 15.5 (4.3) vs 21.5 (4.7) (P= 0.002). The EDITS scores were 67.4 (10.2) for the bupropion and 36.3 (11.7) for the placebo group (P= 0.001). The ASEX score and CGI-SF score were correlated (P= 0.003). In linear regression analyses the CGI-SF score was not affected significantly by the duration of SD, type of SSRI used and age. Bupropion is an effective treatment for male SD induced by SSRIs. These results provide empirical support for conducting a further study of bupropion.

Intestinal Serotonin Transporter Inhibition by Toll-Like Receptor 2 Activation. A Feedback Modulation.

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Eva Latorre

Full Text Available TLR2 is a microbiota recognition receptor that has been described to contribute to intestinal homeostasis and to ameliorate inflammatory intestinal injury. In this context, serotonin (5-HT has shown to be an essential intestinal physiological neuromodulator that is also involved in intestinal inflammatory diseases. Since the interaction between TLR2 activation and the intestinal serotoninergic system remains non-investigated, our main aim was to analyze the effect of TLR2 on intestinal serotonin transporter (SERT activity and expression and the intracellular pathways involved. Caco-2/TC7 cells were used to analyze SERT and TLR2 molecular expression and SERT activity by measuring 5-HT uptake. The results showed that apical TLR2 activation inhibits SERT activity in Caco-2/TC7 cells mainly by reducing SERT protein level either in the plasma membrane, after short-term TLR2 activation or in both the plasma membrane and cell lysate, after long-term activation. cAMP/PKA pathway appears to mediate short-term inhibitory effect of TLR2 on SERT; however, p38 MAPK pathway has been shown to be involved in both short- and long-term TLR2 effect. Reciprocally, 5-HT long-term treatment yielded TLR2 down regulation in Caco-2/TC7 cells. Finally, results from in vivo showed an augmented intestinal SERT expression in mice Tlr2-/-, thus confirming our inhibitory effect of TLR2 on intestinal SERT in vitro. The present work infers that TLR2 may act in intestinal pathophysiology, not only by its inherent innate immune role, but also by regulating the intestinal serotoninergic system.

Comparative efficacy of selective serotonin reuptake inhibitors (SSRI) in treating major depressive disorder: a protocol for network meta-analysis of randomised controlled trials.

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Jia, Yongliang; Zhu, Hongmei; Leung, Siu-Wai

2016-06-07

There have been inconsistent findings from randomised controlled trials (RCTs) and systematic reviews on the efficacies of selective serotonin reuptake inhibitors (SSRIs) as the first-line treatment of major depressive disorder (MDD). Besides inconsistencies among randomised controlled trials (RCTs), their risks of bias and evidence grading have seldom been evaluated in meta-analysis. This study aims to compare the efficacy of SSRIs by conducting a Bayesian network meta-analysis, which will be the most comprehensive evaluation of evidence to resolve the inconsistency among previous studies. SSRIs including citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, sertraline and vilazodone have been selected. Systematic database searching and screening will be conducted for the RCTs on drug treatment of patients with MDD according to pre-specified search strategies and selection criteria. PubMed, the Cochrane Library, EMBASE, ScienceDirect, the US Food and Drug Administration Website, ClinicalTrial.gov and WHO Clinical Trials will be searched. Outcome data including Hamilton Depression Rating Scale (HDRS), Montgomery-Åsberg Depression Rating Scale (MADRS) and Clinical Global Impression (CGI) from eligible RCTs will be extracted. The outcomes will be analysed as ORs and mean differences under a random-effects model. A Bayesian network meta-analysis will be conducted with WinBUGS software, to compare the efficacies of SSRIs. Subgroup and sensitivity analysis will be performed to explain the study heterogeneity and evaluate the robustness of the results. Meta-regression analysis will be conducted to determine the possible factors affecting the efficacy outcomes. The Cochrane risk of bias assessment tool will be used to assess the RCT quality, and the Grading of Recommendation, Assessment, Development and Evaluation will be used to assess the strength of evidence from the meta-analysis. No ethical approval is required because this study includes neither

Milnacipran: a unique antidepressant?

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Siegfried Kasper

2010-08-01

Full Text Available Siegfried Kasper, Gerald PailDepartment of Psychiatry and Psychotherapy, Medical University of Vienna, AustriaAbstract: Tricyclic antidepressants (TCAs are among the most effective antidepressants available, although their poor tolerance at usual recommended doses and toxicity in ­overdose make them difficult to use. While selective serotonin reuptake inhibitors (SSRIs are ­better tolerated than TCAs, they have their own specific problems, such as the aggravation of sexual dysfunction, interaction with coadministered drugs, and for many, a discontinuation syndrome. In addition, some of them appear to be less effective than TCAs in more severely depressed patients. Increasing evidence of the importance of norepinephrine in the etiology of depression has led to the development of a new generation of antidepressants, the serotonin and ­norepinephrine reuptake inhibitors (SNRIs. Milnacipran, one of the pioneer SNRIs, was designed from theoretic considerations to be more effective than SSRIs and better tolerated than TCAs, and with a simple pharmacokinetic profile. Milnacipran has the most balanced potency ratio for reuptake inhibition of the two neurotransmitters compared with other SNRIs (1:1.6 for milnacipran, 1:10 for duloxetine, and 1:30 for venlafaxine, and in some studies milnacipran has been shown to inhibit norepinephrine uptake with greater potency than serotonin (2.2:1. Clinical studies have shown that milnacipran has efficacy comparable with the TCAs and is superior to SSRIs in severe depression. In addition, milnacipran is well tolerated, with a low potential for pharmacokinetic drug–drug interactions. Milnacipran is a first-line therapy suitable for most depressed patients. It is frequently successful when other treatments fail for reasons of efficacy or tolerability.Keywords: milnacipran, SNRI, antidepressant efficacy, tolerability

Obsessive-compulsive disorder in children and adolescents.

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Krebs, Georgina; Heyman, Isobel

2015-05-01

Obsessive-compulsive disorder (OCD) in childhood and adolescence is an impairing condition, associated with a specific set of distressing symptoms incorporating repetitive, intrusive thoughts (obsessions) and distressing, time-consuming rituals (compulsions). This review considers current knowledge of causes and mechanisms underlying OCD, as well as assessment and treatment. Issues relating to differential diagnosis are summarised, including the challenges of distinguishing OCD from autism spectrum disorders and tic disorders in youth. The recommended treatments, namely cognitive behaviour therapy and serotonin reuptake inhibiting/selective serotonin reuptake inhibitor medications, are outlined along with the existing evidence-based and factors associated with treatment resistance. Finally, novel clinical developments that are emerging in the field and future directions for research are discussed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

An investigation into the inhibitory function of serotonin in diffuse noxious inhibitory controls in the neuropathic rat.

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Bannister, K; Lockwood, S; Goncalves, L; Patel, R; Dickenson, A H

2017-04-01

Following neuropathy α2-adrenoceptor-mediated diffuse noxious inhibitory controls (DNIC), whereby a noxious conditioning stimulus inhibits the activity of spinal wide dynamic range (WDR) neurons, are abolished, and spinal 5-HT7 receptor densities are increased. Here, we manipulate spinal 5-HT content in spinal nerve ligated (SNL) animals and investigate which 5-HT receptor mediated actions predominate. Using in vivo electrophysiology we recorded WDR neuronal responses to von frey filaments applied to the hind paw before, and concurrent to, a noxious ear pinch (the conditioning stimulus) in isoflurane-anaesthetised rats. The expression of DNIC was quantified as a reduction in WDR neuronal firing in the presence of conditioning stimulus and was investigated in SNL rats following spinal application of (1) selective serotonin reuptake inhibitors (SSRIs) citalopram or fluoxetine, or dual application of (2) SSRI plus 5-HT7 receptor antagonist SB269970, or (3) SSRI plus α2 adrenoceptor antagonist atipamezole. DNIC were revealed in SNL animals following spinal application of SSRI, but this effect was abolished upon joint application of SSRI plus SB269970 or atipamezole. We propose that in SNL animals the inhibitory actions (quantified as the presence of DNIC) of excess spinal 5-HT (presumed present following application of SSRI) were mediated via 5-HT7 receptors. The anti-nociception depends upon an underlying tonic noradrenergic inhibitory tone via the α2-adrenoceptor. Following neuropathy enhanced spinal serotonin availability switches the predominant spinal 5-HT receptor-mediated actions but also alters noradrenergic signalling. We highlight the therapeutic complexity of SSRIs and monoamine modulators for the treatment of neuropathic pain. © 2016 European Pain Federation - EFIC®.

Self-Limited Kleptomania Symptoms as a Side Effect of Duloxetine

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Miller, Christopher W. T.; Gallagher, Keith E.

2016-01-01

Introduction. Impulse control disorders (ICDs) have been described as a side effect of dopamine agonists, frequently used in neurodegenerative conditions affecting the nigrostriatal pathway. Serotonin-norepinephrine reuptake inhibitors (e.g., duloxetine) have dose-dependent differential affinity for monoaminergic transporters, inhibiting the dopamine transporter at higher doses, thus increasing availability of synaptic dopamine, with the potential for similar impulse control side effects. Cas...

Functioning in patients with major depression treated with duloxetine or a selective serotonin reuptake inhibitor in East Asia

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Novick D

2016-02-01

Full Text Available Diego Novick,1 William Montgomery,2 Josep Maria Haro,3 Maria Victoria Moneta,3 Gang Zhu,4 Li Yue,5 Jihyung Hong,6 Héctor Dueñas,7 Roberto Brugnoli8 1Eli Lilly and Company, Windlesham, Surrey, UK; 2Eli Lilly Australia Pty Ltd, West Ryde, NSW, Australia; 3Parc Sanitari Sant Joan de Déu, Fundació Sant Joan de Déu, CIBERSAM, Universitat de Barcelona, Barcelona, Spain; 4Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, 5Lilly Suzhou Pharmaceutical Company, Ltd, Shanghai, People’s Republic of China; 6Department of Healthcare Management, Gachon University, Seongnam, South Korea; 7Eli Lilly de Mexico, Mexico City, Mexico; 8School of Medicine, Sapienza University of Rome, Rome, ItalyPurpose: To assess and compare the levels of functioning in patients with major depressive disorder treated with either duloxetine with a daily dose of ≤60 mg or a selective serotonin reuptake inhibitor (SSRI as monotherapy for up to 6 months in a naturalistic setting in East Asia. In addition, this study examined the impact of painful physical symptoms (PPS on the effects of these treatments.Patients and methods: Data for this post hoc analysis were taken from a 6-month prospective observational study involving 1,549 patients with major depressive disorder without sexual dysfunction. The present analysis focused on a subgroup of patients from East Asia (n=587. Functioning was measured using the Sheehan Disability Scale (SDS. Depression severity was assessed using the 16-item Quick Inventory of Depressive Symptomatology-Self Report. PPS were rated using the modified Somatic Symptom Inventory. A mixed model with repeated measures was fitted to compare the levels of functioning between duloxetine-treated (n=227 and SSRI-treated (n=225 patients, adjusting for baseline patient characteristics.Results: The mean SDS total score was similar between the two treatment cohorts (15.46 [standard deviation =6.11] in the duloxetine

Changes in EEG indices and serotonin concentrations in depression and anxiety disorders

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I. V. Kichuk

2016-01-01

of a desynchronization pattern.Conclusion. The specific features of EEG in the depression and AD groups may indicate serotonin metabolic disorders and the efficiency of therapy with selective serotonin reuptake inhibitors.

Serotonin syndrome

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Hyperserotonemia; Serotonergic syndrome; Serotonin toxicity; SSRI - serotonin syndrome; MAO - serotonin syndrome ... brain area. For example, you can develop this syndrome if you take migraine medicines called triptans together ...

Computational approaches for the study of serotonin and its membrane transporter SERT: implications for drug design in neurological sciences.

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Pratuangdejkul, J; Schneider, B; Launay, J-M; Kellermann, O; Manivet, P

2008-01-01

Serotonin (5-hydroxytryptamine, 5-HT), a monoamine neurotransmitter of the central nervous and peripheral systems (CNS), plays a critical role in a wide variety of physiological and behavioral processes. In the serotonergic system, deregulation of the tightly controlled extracellular concentration of 5-HT appears to be at the origin of a host of metabolic and psychiatric disorders. A key step that regulates 5-HT external level is the re-uptake of 5-HT into cells by the 5-HT transporter (SERT), which is besides the target of numerous drugs interacting with the serotonergic system. Therapeutic strategies have mainly focused on the development of compounds that block the activity of SERT, for instance reuptake inhibitors (e.g. tricyclics, "selective" serotonin reuptake inhibitors) and in the past, specific substrate-type releasers (e.g. amphetamine and cocaine derivatives). Today, generation of new drugs targetting SERT with enhanced selectivity and reduced toxicity is one of the most challenging tasks in drug design. In this context, studies aiming at characterizing the physicochemical properties of 5-HT as well as the biological active conformation of SERT are a prerequisite to the design of new leads. However, the absence of a high-resolution 3D-structure for SERT has hampered the design of new transporter inhibitors. Using computational approaches, numerous efforts were made to shed light on the structure of 5-HT and its transporter. In this review, we compared several in silico methods dedicated to the modeling of 5-HT and SERT with an emphasis on i) quantum chemistry for study of 5-HT conformation and ii) ligand-based (QSAR and pharmacophore models) and transporter-based (homology models) approaches for studying SERT molecule. In addition, we discuss some methodological aspects of the computational work in connection with the construction of putative but reliable 3D structural models of SERT that may help to predict the mechanisms of neurotransmitter transport.

A randomized controlled trial of a novel mixed monoamine reuptake inhibitor in adults with ADHD

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Wesnes Keith

2008-06-01

Full Text Available Abstract Background NS2359 is a potent reuptake blocker of noradrenalin, dopamine, and serotonin. The aim of the study was to investigate the efficacy, safety and cognitive function of NS2359 in adults with a DSM IV diagnosis of ADHD. Methods The study was a multi-centre, double-blind, randomized placebo-controlled, parallel group design in outpatient adults (18–55 years testing 0.5 mg NS2359 vs. placebo for 8 weeks. Multiple assessments including computerized neuropsychological evaluation were performed. Results There was no significant difference between NS2359 (n = 63 versus placebo (n = 63 on the primary outcome measure reduction in investigator rated ADHD-RS total score (7.8 versus 6.4; p Conclusion No overall effect of NS2359 was found on overall symptoms of ADHD. There was also a modest signal of improvement in the inattentive adults with ADHD and cognition warranting further exploration using differing doses.

Fluoxetine up-regulates expression of cellular FLICE-inhibitory protein and inhibits LPS-induced apoptosis in hippocampus-derived neural stem cell

International Nuclear Information System (INIS)

Chiou, S.-H.; Chen, S.-J.; Peng, C-H.; Chang, Y.-L.; Ku, H.-H.; Hsu, W.-M.; Ho, Larry L.-T.; Lee, C.-H.

2006-01-01

Fluoxetine is a widely used antidepressant compound which inhibits the reuptake of serotonin in the central nervous system. Recent studies have shown that fluoxetine can promote neurogenesis and improve the survival rate of neurons. However, whether fluoxetine modulates the proliferation or neuroprotection effects of neural stem cells (NSCs) needs to be elucidated. In this study, we demonstrated that 20 μM fluoxetine can increase the cell proliferation of NSCs derived from the hippocampus of adult rats by MTT test. The up-regulated expression of Bcl-2, Bcl-xL and the cellular FLICE-inhibitory protein (c-FLIP) in fluoxetine-treated NSCs was detected by real-time RT-PCR. Our results further showed that fluoxetine protects the lipopolysaccharide-induced apoptosis in NSCs, in part, by activating the expression of c-FLIP. Moreover, c-FLIP induction by fluoxetine requires the activation of the c-FLIP promoter region spanning nucleotides -414 to -133, including CREB and SP1 sites. This effect appeared to involve the phosphatidylinositol-3-kinase-dependent pathway. Furthermore, fluoxetine treatment significantly inhibited the induction of proinflammatory factor IL-1β, IL-6, and TNF-α in the culture medium of LPS-treated NSCs (p < 0.01). The results of high performance liquid chromatography coupled to electrochemical detection further confirmed that fluoxentine increased the functional production of serotonin in NSCs. Together, these data demonstrate the specific activation of c-FLIP by fluoxetine and indicate the novel role of fluoxetine for neuroprotection in the treatment of depression

Monoamine reuptake site occupancy of sibutramine: Relationship to antidepressant-like and thermogenic effects in rats.

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Li, Yu-Wen; Langdon, Shaun; Pieschl, Rick; Strong, Todd; Wright, Robert N; Rohrbach, Kenneth; Lelas, Snjezana; Lodge, Nicholas J

2014-08-15

Sibutramine was formerly marketed as an anti-obesity agent. The current study investigated the relationships between monoamine reuptake site occupancy for sibutramine and both its antidepressant-like efficacy and thermogenic effects. Sibutramine's effects on locomotor activity (LMA) and food intake were also evaluated. Sibutramine occupied monoamine reuptake binding sites with the rank order of potency of NET>SERT>DAT; at 10mg/kg, po, occupancy was 95% NET, 81% SERT and 73% DAT. Sibutramine produced antidepressant-like behavior in the forced swim test; at the lowest effective dose (3mg/kg, po) occupancy was 61%, 90% and 23% at SERT, NET and DAT sites, respectively. Sibutramine also increased body core temperature in a dose- and time-dependent manner; at the lowest effective dose (30mg/kg) SERT, NET and DAT occupancies were respectively 78%, 86% and 59%. A significant decrease in food consumption was observed at 3 and 10mg/kg, po. LMA was increased at ≥10mg/kg, sc. The relationship between efficacy in the FST and occupancy was also determined for citalopram, fluoxetine and reboxetine. Similarly, the relationship between thermogenesis and target occupancy for several single or double/triple reuptake inhibitors was measured and showed that >40-50% DAT binding was required for thermogenesis. Thermogenesis was blocked by the D1 antagonist SCH39166 (3mg/kg, sc). Our findings indicate that the antidepressant-like effect of sibutramine may result from additive or synergistic actions on the three reuptake binding targets. At higher doses, sibutramine produces thermogenesis; DAT inhibition and activation of dopamine D1 receptors are required for this effect. Published by Elsevier B.V.

Association of the serotonin transporter-linked polymorphic region genotype with lower bone mineral density.

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Lapid, M I; Kung, S; Frye, M A; Biernacka, J M; Geske, J R; Drake, M T; Jankowski, M D; Clarke, B L

2017-08-22

The serotonin transporter-linked polymorphic region (5-HTTLPR) of the serotonin transporter gene (SLC6A4) S allele is linked to pathogenesis of depression and slower response to selective serotonin reuptake inhibitors (SSRIs); depression and SSRIs are independently associated with bone loss. We aimed to determine whether 5-HTTLPR was associated with bone loss. This cross-sectional study included psychiatric patients with both 5-HTTLPR analysis and bone mineral density (BMD) assessment (hip and spine Z-scores if age <50 years and T-scores if ⩾50 years). BMD association with 5-HTTLPR was evaluated under models with additive allele effects and dominant S allele effects using linear regression models. Patients were stratified by age (<50 and ⩾50 years) and sex. Of 3016 patients with 5-HTTLPR genotyping, 239 had BMD assessments. Among the younger patients, the S allele was associated with lower Z-scores at the hip (P=0.002, dominant S allele effects; P=0.004, additive allele effects) and spine (P=0.0006, dominant S allele effects; P=0.01, additive allele effects). In sex-stratified analyses, the association of the S allele with lower BMD in the younger patients was also significant in the subset of women (P⩽0.003 for both hip and spine BMD under the additive allele effect model). In the small group of men younger than 50 years, the S allele was marginally associated with higher spine BMD (P=0.05). BMD T-scores were not associated with 5-HTTLPR genotypes in patients 50 years or older. The 5-HTTLPR variants may modify serotonin effects on bone with sex-specific effects.

Measuring serotonin synthesis: from conventional methods to PET tracers and their (pre)clinical implications

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Visser, Anniek K.D.; Waarde, Aren van; Willemsen, Antoon T.M. [University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); Bosker, Fokko J. [University of Groningen, University Medical Center Groningen, University Center of Psychiatry, Groningen (Netherlands); Luiten, Paul G.M. [University of Groningen, Center for Behavior and Neurosciences, Department of Molecular Neurobiology, Haren (Netherlands); Boer, Johan A. den [University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University of Groningen, University Medical Center Groningen, University Center of Psychiatry, Groningen (Netherlands); Kema, Ido P. [University of Groningen, University Medical Center Groningen, Department of Laboratory Medicine, Groningen (Netherlands); Dierckx, Rudi A.J.O. [University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University Hospital Ghent, Department of Nuclear Medicine, Ghent (Belgium)

2011-03-15

The serotonergic system of the brain is complex, with an extensive innervation pattern covering all brain regions and endowed with at least 15 different receptors (each with their particular distribution patterns), specific reuptake mechanisms and synthetic processes. Many aspects of the functioning of the serotonergic system are still unclear, partially because of the difficulty of measuring physiological processes in the living brain. In this review we give an overview of the conventional methods of measuring serotonin synthesis and methods using positron emission tomography (PET) tracers, more specifically with respect to serotonergic function in affective disorders. Conventional methods are invasive and do not directly measure synthesis rates. Although they may give insight into turnover rates, a more direct measurement may be preferred. PET is a noninvasive technique which can trace metabolic processes, like serotonin synthesis. Tracers developed for this purpose are {alpha}-[{sup 11}C]methyltryptophan ([{sup 11}C]AMT) and 5-hydroxy-L-[{beta}-{sup 11}C]tryptophan ([{sup 11}C]5-HTP). Both tracers have advantages and disadvantages. [{sup 11}C]AMT can enter the kynurenine pathway under inflammatory conditions (and thus provide a false signal), but this tracer has been used in many studies leading to novel insights regarding antidepressant action. [{sup 11}C]5-HTP is difficult to produce, but trapping of this compound may better represent serotonin synthesis. AMT and 5-HTP kinetics are differently affected by tryptophan depletion and changes of mood. This may indicate that both tracers are associated with different enzymatic processes. In conclusion, PET with radiolabelled substrates for the serotonergic pathway is the only direct way to detect changes of serotonin synthesis in the living brain. (orig.)

Reduced efficacy of fluoxetine following MDMA ("Ecstasy")-induced serotonin loss in rats.

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Durkin, Sarah; Prendergast, Alison; Harkin, Andrew

2008-12-12

Long-term serotonin (5-HT) neuronal loss is currently a major cause of concern associated with recreational use of the substituted amphetamine 3,4 methylenedioxymethamphetamine (MDMA; "Ecstasy"). Such loss may be problematic considering that psychiatric disorders such as depression and anxiety and responses to first line treatments for these disorders are associated with 5-HT. In this study the effects of prior exposure to MDMA on behavioural and central neurochemical changes induced by the serotonin (5-HT) re-uptake inhibitor and antidepressant fluoxetine were examined in rats. Animals were administered MDMA (10 mg/kg. i.p.) four times daily for two consecutive days. One week later the animals were subjected to treatment with fluoxetine (10 mg/kg, i.p.). Fluoxetine treatment groups received either acute (saline injections for 20 days followed by 3 fluoxetine treatments over 24 h) or chronic (once daily fluoxetine for 21 days) drug administration. Prior exposure to MDMA resulted in an attenuation of fluoxetine-induced swimming behaviour in the modified forced swimming test (FST); a behavioural test of antidepressant action. In parallel MDMA treatment resulted in significant regional depletions of 5-HT and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) accompanied by a reduction in cortical [3H] paroxetine binding to nerve terminal 5-HT transporters. MDMA-induced 5-HT loss was enhanced in animals following chronic fluoxetine administration. Elimination of fluoxetine and its metabolite norfluoxetine from the brain abolished this interaction between MDMA and fluoxetine treatment. Fluoxetine administration reduced both 5-HIAA and the 5-HIAA:5-HT metabolism ratio, which was attenuated in animals pre-treated with MDMA. Overall the results show that MDMA induces long-term 5-HT loss in the rodent brain and consequently diminishes behaviour and reductions in 5-HT metabolism induced by the antidepressant fluoxetine. These results have potential clinical relevance

In Vivo Investigation of Escitalopram’s Allosteric Site on the Serotonin Transporter

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Murray, Karen E.; Ressler, Kerry J.; Owens, Michael J.

2015-01-01

Escitalopram is a commonly prescribed antidepressant of the selective serotonin reuptake inhibitor class. Clinical evidence and mapping of the serotonin transporter (SERT) identified that escitalopram, in addition to its binding to a primary uptake-blocking site, is capable of binding to the SERT via an allosteric site that is hypothesized to alter escitalopram’s kinetics at the SERT. The studies reported here examined the in vivo role of the SERT allosteric site in escitalopram action. A knockin mouse model that possesses an allosteric-null SERT was developed. Autoradiographic studies indicated that the knockin protein was expressed at a lower density than endogenous mouse SERT (approximately 10–30% of endogenous mouse SERT), but the knockin mice are a viable tool to study the allosteric site. Microdialysis studies in the ventral hippocampus found no measurable decrease in extracellular serotonin response after local escitalopram challenge in mice without the allosteric site compared to mice with the site (p = 0.297). In marble burying assays there was a modest effect of the absence of the allosteric site, with a larger systemic dose of escitalopram (10-fold) necessary for the same effect as in mice with intact SERT (p = 0.023). However, there was no effect of the allosteric site in the tail suspension test. Together these data suggest that there may be a regional specificity in the role of the allosteric site. The lack of a robust effect overall suggests that the role of the allosteric site for escitalopram on the SERT may not produce meaningful in vivo effects. PMID:26621784

Serotonin is critical for rewarded olfactory short-term memory in Drosophila.

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Sitaraman, Divya; LaFerriere, Holly; Birman, Serge; Zars, Troy

2012-06-01

The biogenic amines dopamine, octopamine, and serotonin are critical in establishing normal memories. A common view for the amines in insect memory performance has emerged in which dopamine and octopamine are largely responsible for aversive and appetitive memories. Examination of the function of serotonin begins to challenge the notion of one amine type per memory because altering serotonin function also reduces aversive olfactory memory and place memory levels. Could the function of serotonin be restricted to the aversive domain, suggesting a more specific dopamine/serotonin system interaction? The function of the serotonergic system in appetitive olfactory memory was examined. By targeting the tetanus toxin light chain (TNT) and the human inwardly rectifying potassium channel (Kir2.1) to the serotonin neurons with two different GAL4 driver combinations, the serotonergic system was inhibited. Additional use of the GAL80(ts1) system to control expression of transgenes to the adult stage of the life cycle addressed a potential developmental role of serotonin in appetitive memory. Reduction in appetitive olfactory memory performance in flies with these transgenic manipulations, without altering control behaviors, showed that the serotonergic system is also required for normal appetitive memory. Thus, serotonin appears to have a more general role in Drosophila memory, and implies an interaction with both the dopaminergic and octopaminergic systems.

Autoradiographic localization of 3H-paroxetine-labeled serotonin uptake sites in rat brain

International Nuclear Information System (INIS)

De Souza, E.B.; Kuyatt, B.L.

1987-01-01

Paroxetine is a potent and selective inhibitor of serotonin uptake into neurons. Serotonin uptake sites have been identified, localized, and quantified in rat brain by autoradiography with 3H-paroxetine; 3H-paroxetine binding in slide-mounted sections of rat forebrain was of high affinity (KD = 10 pM) and the inhibition affinity constant (Ki) values of various drugs in competing 3H-paroxetine binding significantly correlated with their reported potencies in inhibiting synaptosomal serotonin uptake. Serotonin uptake sites labeled by 3H-paroxetine were highly concentrated in the dorsal and median raphe nuclei, central gray, superficial layer of the superior colliculus, lateral septal nucleus, paraventricular nucleus of the thalamus, and the islands of Calleja. High concentrations of 3H-paroxetine binding sites were found in brainstem areas containing dopamine (substantia nigra and ventral tegmental area) and norepinephrine (locus coeruleus) cell bodies. Moderate concentrations of 3H-paroxetine binding sites were present in laminae I and IV of the frontal parietal cortex, primary olfactory cortex, olfactory tubercle, regions of the basal ganglia, septum, amygdala, thalamus, hypothalamus, hippocampus, and some brainstem areas including the interpeduncular, trigeminal, and parabrachial nuclei. Lower densities of 3H-paroxetine binding sites were found in other regions of the neocortex and very low to nonsignificant levels of binding were present in white matter tracts and in the cerebellum. Lesioning of serotonin neurons with 3,4-methylenedioxyamphetamine caused large decreases in 3H-paroxetine binding. The autoradiographic distribution of 3H-paroxetine binding sites in rat brain corresponds extremely well to the distribution of serotonin terminals and cell bodies as well as with the pharmacological sites of action of serotonin

Mapping the Binding Site for Escitalopram and Paroxetine in the Human Serotonin Transporter Using Genetically Encoded Photo-Cross-Linkers

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Rannversson, Hafsteinn; Andersen, Jacob; Bang-Andersen, Benny

2017-01-01

amber codon suppression in hSERT to encode the photo-cross-linking unnatural amino acid p-azido-l-phenylalanine into the suggested high- and low-affinity binding sites. We then employ UV-induced cross-linking with azF to map the binding site of escitalopram and paroxetine, two prototypical selective...... serotonin reuptake inhibitors (SSRIs). We find that the two antidepressant drugs exclusively cross-link to azF incorporated at the high-affinity binding site of hSERT, while cross-linking is not observed at the low-affinity binding site. Combined with previous homology models and recent structural data on h...

Docosahexaenoyl serotonin emerges as most potent inhibitor of IL-17 and CCL-20 released by blood mononuclear cells from a series of N-acyl serotonins identified in human intestinal tissue.

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Wang, Ya; Balvers, Michiel G J; Hendriks, Henk F J; Wilpshaar, Tessa; van Heek, Tjarda; Witkamp, Renger F; Meijerink, Jocelijn

2017-09-01

Fatty acid amides (FAAs), conjugates of fatty acids with ethanolamine, mono-amine neurotransmitters or amino acids are a class of molecules that display diverse functional roles in different cells and tissues. Recently we reported that one of the serotonin-fatty acid conjugates, docosahexaenoyl serotonin (DHA-5-HT), previously found in gut tissue of mouse and pig, attenuates the IL-23-IL-17 signaling axis in LPS-stimulated mice macrophages. However, its presence and effects in humans remained to be elucidated. Here, we report for the first time its identification in human intestinal (colon) tissue, along with a series of related N-acyl serotonins. Furthermore, we tested these fatty acid conjugates for their ability to inhibit the release of IL-17 and CCL-20 by stimulated human peripheral blood mononuclear cells (PBMCs). Serotonin conjugates with palmitic acid (PA-5-HT), stearic acid (SA-5-HT) and oleic acid (OA-5-HT) were detected in higher levels than arachidonoyl serotonin (AA-5-HT) and DHA-5-HT, while eicosapentaenoyl serotonin (EPA-5-HT) could not be quantified. Among these, DHA-5-HT was the most potent in inhibiting IL-17 and CCL-20, typical Th17 pro-inflammatory mediators, by Concanavalin A (ConA)-stimulated human PBMCs. These results underline the idea that DHA-5-HT is a gut-specific endogenously produced mediator with the capacity to modulate the IL-17/Th17 signaling response. Our findings may be of relevance in relation to intestinal inflammatory diseases like Crohn's disease and Ulcerative colitis. Copyright © 2017. Published by Elsevier B.V.

Serotonin transporter and dopamine transporter imaging in the canine brain

International Nuclear Information System (INIS)

Peremans, Kathelijne; Goethals, Ingeborg; De Vos, Filip; Dobbeleir, A.; Ham, Hamphrey; Van Bree, Henri; Heeringen, Cees van; Audenaert, Kurt

2006-01-01

The serotonergic and dopaminergic systems are involved in a wide range of emotional and behavioral aspects of animals and humans and are involved in many neuropsychiatric disorders. Selective serotonin (5-HT) reuptake inhibitors (SSRIs) are designed to block the 5-HT transporter (SERT), thereby increasing the available 5-HT in the brain. Functional imaging with specific SERT and dopamine transporter (DAT) ligands contributes to the study of the SSRI-transporter interaction. First, we evaluated the feasibility of a canine model in the study of the SERT and DAT with the radioligands [ 123 I]-β-CIT and [ 123 I]-FP-CIT as well as single-photon emission computed tomography imaging. Second, we studied the effect of SSRIs (sertraline, citalopram and escitalopram) on the SERT and DAT in two dogs. The position of the canine model in the study of the SERT and DAT is discussed and compared with other animal models

Serotonin spillover onto the axon initial segment of motoneurons induces central fatigue by inhibiting action potential initiation

DEFF Research Database (Denmark)

Cotel, Florence; Exley, Richard; Cragg, Stephanie

2013-01-01

Motor fatigue induced by physical activity is an everyday experience characterized by a decreased capacity to generate motor force. Factors in both muscles and the central nervous system are involved. The central component of fatigue modulates the ability of motoneurons to activate muscle...... adequately independently of the muscle physiology. Indirect evidence indicates that central fatigue is caused by serotonin (5-HT), but the cellular mechanisms are unknown. In a slice preparation from the spinal cord of the adult turtle, we found that prolonged stimulation of the raphe-spinal pathway......-HT during motor activity spills over from its release sites to the AIS of motoneurons. Here, activated 5-HT1A receptors inhibit firing and, thereby, muscle contraction. Hence, this is a cellular mechanism for central fatigue...

Autoradiographic study of serotonin transporter during memory formation.

Science.gov (United States)

Tellez, Ruth; Rocha, Luisa; Castillo, Carlos; Meneses, Alfredo

2010-09-01

Serotonin transporter (SERT) has been associated with drugs of abuse like d-methamphetamine (METH). METH is well known to produce effects on the monoamine systems but it is unclear how METH affects SERT and memory. Here the effects of METH and the serotonin reuptake inhibitor fluoxetine (FLX) on autoshaping and novel object recognition (NOR) were investigated. Notably, both memory tasks recruit different behavioral, neural and cognitive demand. In autoshaping task a dose-response curve for METH was determined. METH (1.0mg/kg) impaired short-term memory (STM; lasting less of 90min) in NOR and impaired both STM and long-term memory (LTM; lasting 24 and 48h) in autoshaping, indicating that METH had long-lasting effects in the latter task. A comparative autoradiography study of the relationship between the binding pattern of SERT in autoshaping new untrained vs. trained treated (METH, FLX, or both) animals was made. Considering that hemispheric dominance is important for LTM, hence right vs. left hemisphere of the brain was compared. Results showed that trained animals decreased cortical SERT binding relative to untrained ones. In untrained and trained treated animals with the amnesic dose (1.0mg/kg) of METH SERT binding in several areas including hippocampus and cortex decreased, more remarkably in the trained animals. In contrast, FLX improved memory, increased SERT binding, prevented the METH amnesic effect and re-established the SERT binding. In general, memory and amnesia seemed to make SERT more vulnerable to drugs effects. Copyright 2010 Elsevier B.V. All rights reserved.

Mechanism of action of narcolepsy medications.

Science.gov (United States)

Gowda, Chandan R; Lundt, Leslie P

2014-12-01

The medications used to treat narcolepsy are targeted toward alleviating symptoms such as excessive sleepiness and cataplexy. The cause of this neurological sleep disorder is still not completely clear, though a destruction of hypocretin/orexin neurons has been implicated. The destruction of these neurons is linked to inactivity of neurotransmitters including histamine, norepinephrine, acetylcholine, and serotonin, causing a disturbance in the sleep/wake cycles of narcoleptic patients. Stimulants and MAOIs have traditionally been used to counteract excessive daytime sleepiness and sleep attacks by inhibiting the breakdown of catecholamines. Newer drugs, called wake-promoting agents, have recently become first-line agents due to their better side-effect profile, efficacy, and lesser potential for abuse. These agents similarly inhibit reuptake of dopamine, but have a novel mechanism of action, as they have been found to increase neuronal activity in the tuberomamillary nucleus and in orexin neurons. Sodium oxybate, a sodium salt of gamma-hydroxybutyrate (GHB), is another class that is used to treat many symptoms of narcolepsy, and is the only U.S. Food and Drug Administration (FDA)-approved medication for cataplexy. It has a different mechanism of action than either stimulants or wake-promoting agents, as it binds to its own unique receptor. Antidepressants, like selective serotonin re-uptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs), have also been used, as similar to stimulants, they inhibit reuptake of specific catecholamines. In this article, we seek to review the mechanisms behind these classes of drugs in relation to the proposed pathophysiology of narcolepsy. Appropriate clinical strategies will be discussed, including specific combinations of medications that have been shown to be effective.

[From valium to the happy pill?].

Science.gov (United States)

Thormodsen, M; Hjortdahl, P; Farbrot, T; Jacobsen, O V; Nenningsland, J B; Nielsen, B B; Nielsen, B B

1999-06-10

The National Health Insurance started to refund expenditure on selective serotonin reuptake inhibitors in 1994. Questions have been raised if a significant portion of benzodiazepine users would transfer to these new drugs when they were described in the literature as also being used for light anxiety, but not carrying the addiction risk associated with benzodiazepines. The study looks at changes over a four-year period in the prescription of benzodiazepines and selective serotonin reuptake inhibitors dispensed from two pharmacies in Vest-Agder County with a total customer base of 17,800. For four years we also followed the prescription of drugs in these two groups to 1,125 patients who had been prescribed benzodiazepines in 1994. Our data show that only 5% of those receiving benzodiazepines in 1994, whom we were able to track, changed to a selective serotonin reuptake inhibitor-only therapy. 18% used a combination of the two groups of drugs and 77% continued to use benzodiazepines as before. The increase in the number of patients receiving selective serotonin reuptake inhibitors during the study period is far greater than the increase measured by number of daily doses. Selective serotonin reuptake inhibitors seem to have little influence on the use of benzodiazepines in our pharmacies' area. Our findings indicate that instead of "from Valium to Prozac" the change during the years 1994-97 can be described as "from Valium to Valium and Prozac".

Omega-3 Fatty Acid Deficiency Does Not Alter the Effects of Chronic Fluoxetine Treatment on Central Serotonin Turnover or Behavior in the Forced Swim Test in Female Rats

OpenAIRE

McNamara, Robert K.; Able, Jessica A.; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; Lipton, Jack W.

2013-01-01

While translational evidence suggests that long-chain omega-3 fatty acid status is positively associated with the efficacy of selective serotonin reuptake inhibitor drugs, the neurochemical mechanisms mediating this interaction are not known. Here we investigated the effects of dietary omega-3 (n-3) fatty acid insufficiency on the neurochemical and behavioral effects of chronic fluoxetine (FLX) treatment. Female rats were fed diets with (CON, n=56) or without (DEF, n=40) the n-3 fatty acids d...

Serotonergic mediation of the effects of fluoxetine, but not desipramine, in the rat forced swimming test.

Science.gov (United States)

Page, M E; Detke, M J; Dalvi, A; Kirby, L G; Lucki, I

1999-11-01

The forced swimming test (FST) is a behavioral test in rodents that predicts the clinical efficacy of many types of antidepressant treatments. Recently, a behavior sampling technique was developed that scores individual response categories, including swimming, climbing and immobility. Although all antidepressant drugs reduce immobility in the FST, at least two distinct active behavioral patterns are produced by pharmacologically selective antidepressant drugs. Serotonin-selective reuptake inhibitors increase swimming behavior, while drugs acting primarily to increase extracellular levels of norepinephrine or dopamine increase climbing behavior. Distinct patterns of active behaviors in the FST may be mediated by distinct neurotransmitters, but this has not been shown directly. The present study examined the role of serotonin in mediating active behaviors in the forced swimming test after treatment with two antidepressant drugs, the selective serotonin reuptake inhibitor, fluoxetine and the selective norepinephrine reuptake inhibitor, desipramine. Endogenous serotonin was depleted by administering para-cholorophenylalanine (PCPA, 150 mg/kg, IP.) to rats 72 h and 48 h prior to the swim test. Fluoxetine (10 mg/kg, SC) or desipramine (10 mg/kg, SC) was given three times over a 24-h period prior to the FST. Behavioral responses, including immobility, swimming and climbing, were counted during the 5-min test. Pretreatment with PCPA blocked fluoxetine-induced reduction in immobility and increase in swimming behavior during the FST. In contrast, PCPA pretreatment did not interfere with the ability of desipramine to reduce immobility and increase climbing behavior. Depletion of serotonin prevented the behavioral effects of the selective serotonin reuptake inhibitor fluoxetine in the rat FST. Furthermore, depletion of serotonin had no impact on the behavioral effects induced by the selective norepinephrine reuptake inhibitor, desipramine. The effects of antidepressant drugs

Serotonin transporter gene polymorphism and myocardial infarction: Etude Cas-Témoins de l'Infarctus du Myocarde (ECTIM).

Science.gov (United States)

Fumeron, Frédéric; Betoulle, Dina; Nicaud, Viviane; Evans, Alun; Kee, Frank; Ruidavets, Jean-Bernard; Arveiler, Dominique; Luc, Gérald; Cambien, François

2002-06-25

Depression is a risk factor for myocardial infarction (MI). Selective serotonin reuptake inhibitors reduce this risk. The site of action is the serotonin transporter (SLC6A4), which is expressed in brain and blood cells. A functional polymorphism in the promoter region of the SLC6A4 gene has been described. This polymorphism may be associated with the risk of MI. The SLC6A4 polymorphism has been investigated by polymerase chain reaction in 671 male patients with MI and in 688 controls from the Etude Cas-Témoins de l'Infarctus du Myocarde (ECTIM) multicentric study. Percentages for LL, LS, and SS genotypes were 35.5%, 45.4%, and 19.1%, respectively, for cases versus 28.1%, 49.1%, and 22.8%, respectively, for controls. S allele frequency was 41.8% and 47.4% for cases and controls, respectively. After adjustment for age and center by using multivariable logistic regression, the odds ratio for MI associated with the LL genotype was 1.40 (95% CI 1.11 to 1.76, P=0.0047). The LL genotype of the SLC6A4 polymorphism is associated with a higher risk of MI. This could be attributable to the effect of the polymorphism on serotonin-mediated platelet activation or smooth muscle cell proliferation or on other risk factors, such as depression or response to stress.

Intrinsic neuromodulation in the Tritonia swim CPG: serotonin mediates both neuromodulation and neurotransmission by the dorsal swim interneurons.

Science.gov (United States)

Katz, P S; Frost, W N

1995-12-01

1. Neuromodulation has previously been shown to be intrinsic to the central pattern generator (CPG) circuit that generates the escape swim of the nudibranch mollusk Tritonia diomedea; the dorsal swim interneurons (DSIs) make conventional monosynaptic connections and evoke neuromodulatory effects within the swim motor circuit. The conventional synaptic potentials evoked by a DSI onto cerebral neuron 2 (C2) and onto the dorsal flexion neurons (DFNs) consist of a fast excitatory postsynaptic potential (EPSP) followed by a prolonged slow EPSP. In their neuromodulatory role, the DSIs produce an enhancement of the monosynaptic connections made by C2 onto other CPG circuit interneurons and onto efferent flexion neurons. Previous work showed that the DSIs are immunoreactive for serotonin. Here we provide evidence that both the neurotransmission and the neuromodulation evoked by the DSIs are produced by serotonin, and that these effects may be pharmacologically separable. 2. Previously it was shown that bath-applied serotonin both mimics and occludes the modulation of the C2 synapses by the DSIs. Here we find that pressure-applied puffs of serotonin mimic both the fast and slow EPSPs evoked by a DSI onto a DFN, whereas high concentrations of bath-applied serotonin occlude both of these synaptic components. 3. Consistent with the hypothesis that serotonin mediates the actions of the DSIs, the serotonin reuptake inhibitor imipramine prolongs the duration of the fast DSI-DFN EPSP, increases the amplitude of the slow DSI-DFN EPSP, and increases both the amplitude and duration of the modulation of the C2-DFN synapse by the DSIs. 4. Two serotonergic antagonists were found that block the actions of the DSIs. Gramine blocks the fast DSI-DFN EPSP, and has far less of an effect on the slow EPSP and the modulation. Gramine also diminishes the depolarization evoked by pressure-applied serotonin, showing that it is a serotonin antagonist in this system. In contrast, methysergide greatly

Biodistribution and dosimetry of 123I-mZIENT: a novel ligand for imaging serotonin transporters

International Nuclear Information System (INIS)

Nicol, Alice; Krishnadas, Rajeev; Champion, Sue; Tamagnan, Gilles; Stehouwer, Jeffrey S.; Goodman, Mark M.; Hadley, Donald M.; Pimlott, Sally L.

2012-01-01

123 I-labelled mZIENT (2β-carbomethoxy-3β-(3'-((Z)-2-iodoethenyl)phenyl)nortropane) has been developed as a radioligand for the serotonin transporter. The aim of this preliminary study was to assess its whole-body biodistribution in humans and estimate dosimetry. Three healthy controls and three patients receiving selective serotonin reuptake inhibitor (SSRI) therapy for depression were included (two men, four women, age range 41-56 years). Whole-body imaging, brain SPECT imaging and blood and urine sampling were performed. Whole-body images were analysed using regions of interest (ROIs), time-activity curves were derived using compartmental analysis and dosimetry estimated using OLINDA software. Brain ROI analysis was performed to obtain specific-to-nonspecific binding ratios in the midbrain, thalamus and striatum. Initial high uptake in the lungs decreased in later images. Lower uptake was seen in the brain, liver and intestines. Excretion was primarily through the urinary system. The effective dose was estimated to be of the order of 0.03 mSv/MBq. The organ receiving the highest absorbed dose was the lower large intestine wall. Uptake in the brain was consistent with the known SERT distribution with higher specific-to-nonspecific binding in the midbrain, thalamus and striatum in healthy controls compared with patients receiving SSRI therapy. 123 I-mZIENT may be a promising radioligand for imaging the serotonin transporters in humans with acceptable dosimetry. (orig.)

The antidepressant sertraline inhibits translation initiation by curtailing mammalian target of rapamycin signaling.

Science.gov (United States)

Lin, Chen-Ju; Robert, Francis; Sukarieh, Rami; Michnick, Stephen; Pelletier, Jerry

2010-04-15

Sertraline, a selective serotonin reuptake inhibitor, is a widely used antidepressant agent. Here, we show that sertraline also exhibits antiproliferative activity. Exposure to sertraline leads to a concentration-dependent decrease in protein synthesis. Moreover, polysome profile analysis of sertraline-treated cells shows a reduction in polysome content and a concomitant increase in 80S ribosomes. The inhibition in translation caused by sertraline is associated with decreased levels of the eukaryotic initiation factor (eIF) 4F complex, altered localization of eIF4E, and increased eIF2alpha phosphorylation. The latter event leads to increased REDD1 expression, which in turn impinges on the mammalian target of rapamycin (mTOR) pathway by affecting TSC1/2 signaling. Sertraline also independently targets the mTOR signaling pathway downstream of Rheb. In the Emu-myc murine lymphoma model where carcinogenesis is driven by phosphatase and tensin homologue (PTEN) inactivation, sertraline is able to enhance chemosensitivity to doxorubicin. Our results indicate that sertraline exerts antiproliferative activity by targeting the mTOR signaling pathway in a REDD1-dependent manner. (c) 2010 AACR.

The analgesic agent tapentadol inhibits calcitonin gene-related peptide release from isolated rat brainstem via a serotonergic mechanism.

Science.gov (United States)

Greco, Maria Cristina; Navarra, Pierluigi; Tringali, Giuseppe

2016-01-15

In this study we tested the hypothesis that tapentadol inhibits GGRP release from the rat brainstem through a mechanism mediated by the inhibition of NA reuptake; as a second alternative hypothesis, we investigated whether tapentadol inhibits GGRP release via the inhibition of 5-HT reuptake. Rat brainstems were explanted and incubated in short-term experiments. CGRP released in the incubation medium was taken as a marker of CGRP release from the central terminals of trigeminal neurons within the brainstem. CGRP levels were measured by radioimmunoassay under basal conditions or in the presence of tapentadol; NA, 5-HT, clonidine, yohimbine and ondansetron were used as pharmacological tools to investigate the action mechanism of tapentadol. The α2-antagonist yohimbine failed to counteract the effects of tapentadol. Moreover, neither NA nor the α2-agonist clonidine per se inhibited K(+)-stimulated CGRP release, thereby indicating that the effects of tapentadol are nor mediated through the block of NA reuptake. Further experiments showed that 5-HT and tramadol, which inhibits both NA and 5-HT reuptake, significantly reduced K(+)-stimulated CGRP release. Moreover, the 5-HT3 antagonist ondansetron was able to counteract the effects of tapentadol in this system. This study provided pharmacological evidence that tapentadol inhibits stimulated CGRP release from the rat brainstem in vitro through a mechanism involving an increase in 5-HT levels in the system and the subsequent activation of 5-HT3 receptors. Copyright © 2015 Elsevier Inc. All rights reserved.

Transient inhibition and long-term facilitation of locomotion by phasic optogenetic activation of serotonin neurons

Science.gov (United States)

Correia, Patrícia A; Lottem, Eran; Banerjee, Dhruba; Machado, Ana S; Carey, Megan R; Mainen, Zachary F

2017-01-01

Serotonin (5-HT) is associated with mood and motivation but the function of endogenous 5-HT remains controversial. Here, we studied the impact of phasic optogenetic activation of 5-HT neurons in mice over time scales from seconds to weeks. We found that activating dorsal raphe nucleus (DRN) 5-HT neurons induced a strong suppression of spontaneous locomotor behavior in the open field with rapid kinetics (onset ≤1 s). Inhibition of locomotion was independent of measures of anxiety or motor impairment and could be overcome by strong motivational drive. Repetitive place-contingent pairing of activation caused neither place preference nor aversion. However, repeated 15 min daily stimulation caused a persistent increase in spontaneous locomotion to emerge over three weeks. These results show that 5-HT transients have strong and opposing short and long-term effects on motor behavior that appear to arise from effects on the underlying factors that motivate actions. DOI: http://dx.doi.org/10.7554/eLife.20975.001 PMID:28193320

Genetic predictors of response to serotonergic and noradrenergic antidepressants in major depressive disorder: a genome-wide analysis of individual-level data and a meta-analysis.

Directory of Open Access Journals (Sweden)

Katherine E Tansey

Full Text Available It has been suggested that outcomes of antidepressant treatment for major depressive disorder could be significantly improved if treatment choice is informed by genetic data. This study aims to test the hypothesis that common genetic variants can predict response to antidepressants in a clinically meaningful way.The NEWMEDS consortium, an academia-industry partnership, assembled a database of over 2,000 European-ancestry individuals with major depressive disorder, prospectively measured treatment outcomes with serotonin reuptake inhibiting or noradrenaline reuptake inhibiting antidepressants and available genetic samples from five studies (three randomized controlled trials, one part-randomized controlled trial, and one treatment cohort study. After quality control, a dataset of 1,790 individuals with high-quality genome-wide genotyping provided adequate power to test the hypotheses that antidepressant response or a clinically significant differential response to the two classes of antidepressants could be predicted from a single common genetic polymorphism. None of the more than half million genetic markers significantly predicted response to antidepressants overall, serotonin reuptake inhibitors, or noradrenaline reuptake inhibitors, or differential response to the two types of antidepressants (genome-wide significance p<5×10(-8. No biological pathways were significantly overrepresented in the results. No significant associations (genome-wide significance p<5×10(-8 were detected in a meta-analysis of NEWMEDS and another large sample (STAR*D, with 2,897 individuals in total. Polygenic scoring found no convergence among multiple associations in NEWMEDS and STAR*D.No single common genetic variant was associated with antidepressant response at a clinically relevant level in a European-ancestry cohort. Effects specific to particular antidepressant drugs could not be investigated in the current study. Please see later in the article for the

Serotonin transporter and dopamine transporter imaging in the canine brain

Energy Technology Data Exchange (ETDEWEB)

Peremans, Kathelijne [Department of Medical Imaging, Faculty of Veterinary Sciences, Ghent University, B-9000 Ghent (Belgium); Goethals, Ingeborg [Division of Nuclear Medicine, University Hospital Ghent, B-9000 Ghent (Belgium); De Vos, Filip [Laboratory of Radiopharmacy, Pharmaceutical Sciences, Ghent University, B-9000 Ghent (Belgium); Dobbeleir, A. [Department of Medical Imaging, Faculty of Veterinary Sciences, Ghent University, B-9000 Ghent (Belgium); Ham, Hamphrey [Division of Nuclear Medicine, University Hospital Ghent, B-9000 Ghent (Belgium); Van Bree, Henri [Department of Medical Imaging, Faculty of Veterinary Sciences, Ghent University, B-9000 Ghent (Belgium); Heeringen, Cees van [Department of Psychiatry and Medical Psychology, Faculty of Medical and Health Sciences, Ghent University, B-9000, Ghent (Belgium); Audenaert, Kurt [Division of Nuclear Medicine, University Hospital Ghent, B-9000 Ghent (Belgium) and Department of Psychiatry and Medical Psychology, Faculty of Medical and Health Sciences, Ghent University, B-9000, Ghent (Belgium)]. E-mail: kurt.audenaert@ugent.be

2006-10-15

The serotonergic and dopaminergic systems are involved in a wide range of emotional and behavioral aspects of animals and humans and are involved in many neuropsychiatric disorders. Selective serotonin (5-HT) reuptake inhibitors (SSRIs) are designed to block the 5-HT transporter (SERT), thereby increasing the available 5-HT in the brain. Functional imaging with specific SERT and dopamine transporter (DAT) ligands contributes to the study of the SSRI-transporter interaction. First, we evaluated the feasibility of a canine model in the study of the SERT and DAT with the radioligands [{sup 123}I]-{beta}-CIT and [{sup 123}I]-FP-CIT as well as single-photon emission computed tomography imaging. Second, we studied the effect of SSRIs (sertraline, citalopram and escitalopram) on the SERT and DAT in two dogs. The position of the canine model in the study of the SERT and DAT is discussed and compared with other animal models.

Preclinical pharmacological study on I-ADAM as a serotonin transporter ligand

International Nuclear Information System (INIS)

Wu Chunying; Lu Chunxiong; Jiang Quanfu; Zou Meifen; Chen Zhengping; Wang Songpei; Li Xiaomin; Zhang Tongxing; Zhu Junqing; Lin Xiangtong

2004-01-01

Objective: To evaluate the new ligand: I-2-( (22( (dimethylamino) methyl) phenyl) thio)-5- iodophenylamine (ADAM) as a serotonin imaging agent. Methods: Biological evaluations were performed in rats and mice. Results: Biodistribution studies in rats showed that the initial uptake of 131 I-ADAM in the brain was high (1.087%ID/organ at 2 min postinjection), and consistently displayed the highest binding (between 60-240 min postinjection) in hypothalamus, a region with the highest density of serotonin transporter (SERT). The specific binding [(TPCB)-1] of 131 I-ADAM in hypothalamus was 2.94, 3.03 and 3.09 at 60, 120 and 240 min postinjection, respectively. The (TPCB)-1 was significantly blocked by pretreatment with Paroxetine, which is known as a serotonin site reuptake inhibitor, while another nonselective competing drug, Ketanserin, showed no blocking effect. The rat brain autoradiography and analysis showed that there was high 131 I-ADAM uptake in hypothalamus, the ratio of hypothalamus/cerebellum was significantly reduced from 7.94 ± 0.39 to 1.30 ± 0.56 by pretreatment with Paroxetine at 60 min postinjection. Blood clearance kinetics was studied in rats, and the initial half-life of 13.79 min and late half-life of 357.14 min were obtained. The kinetic equation was: C=3.6147·e -0.0725t + 1.0413 e -0.0028t . The thyroid uptake was 0.009 and 1.421% ID/organ at 2 min and 120 min postinjection, respectively, suggesting that in vivo deiodination maybe the major route of metabolism. Toxicity trial showed that the dose per kilogram administered to mice was 1000 times greater than that to human beings, assuming a body-weight of 50 kg. Conclusion: These data suggest that 131 I-ADAM may be useful for SPECT imaging of SERT binding sits in the brain. (authors)

Risk of upper gastrointestinal bleeding with selective serotonin reuptake inhibitors with or without concurrent nonsteroidal anti-inflammatory use: a systematic review and meta-analysis.

Science.gov (United States)

Anglin, Rebecca; Yuan, Yuhong; Moayyedi, Paul; Tse, Frances; Armstrong, David; Leontiadis, Grigorios I

2014-06-01

There is emerging concern that selective serotonin reuptake inhibitors (SSRIs) may be associated with an increased risk of upper gastrointestinal (GI) bleeding, and that this risk may be further increased by concurrent use of nonsteroidal anti-inflammatory (NSAID) medications. Previous reviews of a relatively small number of studies have reported a substantial risk of upper GI bleeding with SSRIs; however, more recent studies have produced variable results. The objective of this study was to obtain a more precise estimate of the risk of upper GI bleeding with SSRIs, with or without concurrent NSAID use. MEDLINE, EMBASE, PsycINFO, the Cochrane central register of controlled trials (through April 2013), and US and European conference proceedings were searched. Controlled trials, cohort, case-control, and cross-sectional studies that reported the incidence of upper GI bleeding in adults on SSRIs with or without concurrent NSAID use, compared with placebo or no treatment were included. Data were extracted independently by two authors. Dichotomous data were pooled to obtain odds ratio (OR) of the risk of upper GI bleeding with SSRIs +/- NSAID, with a 95% confidence interval (CI). The main outcome and measure of the study was the risk of upper GI bleeding with SSRIs compared with placebo or no treatment. Fifteen case-control studies (including 393,268 participants) and four cohort studies were included in the analysis. There was an increased risk of upper GI bleeding with SSRI medications in the case-control studies (OR=1.66, 95% CI=1.44,1.92) and cohort studies (OR=1.68, 95% CI=1.13,2.50). The number needed to harm for upper GI bleeding with SSRI treatment in a low-risk population was 3,177, and in a high-risk population it was 881. The risk of upper GI bleeding was further increased with the use of both SSRI and NSAID medications (OR=4.25, 95% CI=2.82,6.42). SSRI medications are associated with a modest increase in the risk of upper GI bleeding, which is lower than has

Differential regulation of the excitability of prefrontal cortical fast-spiking interneurons and pyramidal neurons by serotonin and fluoxetine.

Directory of Open Access Journals (Sweden)

Ping Zhong

2011-02-01

Full Text Available Serotonin exerts a powerful influence on neuronal excitability. In this study, we investigated the effects of serotonin on different neuronal populations in prefrontal cortex (PFC, a major area controlling emotion and cognition. Using whole-cell recordings in PFC slices, we found that bath application of 5-HT dose-dependently increased the firing of FS (fast spiking interneurons, and decreased the firing of pyramidal neurons. The enhancing effect of 5-HT in FS interneurons was mediated by 5-HT₂ receptors, while the reducing effect of 5-HT in pyramidal neurons was mediated by 5-HT₁ receptors. Fluoxetine, the selective serotonin reuptake inhibitor, also induced a concentration-dependent increase in the excitability of FS interneurons, but had little effect on pyramidal neurons. In rats with chronic fluoxetine treatment, the excitability of FS interneurons was significantly increased, while pyramidal neurons remained unchanged. Fluoxetine injection largely occluded the enhancing effect of 5-HT in FS interneurons, but did not alter the reducing effect of 5-HT in pyramidal neurons. These data suggest that the excitability of PFC interneurons and pyramidal neurons is regulated by exogenous 5-HT in an opposing manner, and FS interneurons are the major target of Fluoxetine. It provides a framework for understanding the action of 5-HT and antidepressants in altering PFC network activity.

Biodistribution and dosimetry of {sup 123}I-mZIENT: a novel ligand for imaging serotonin transporters

Energy Technology Data Exchange (ETDEWEB)

Nicol, Alice [NHS Greater Glasgow and Clyde, Department of Nuclear Medicine, Southern General Hospital, Glasgow (United Kingdom); Krishnadas, Rajeev [University of Glasgow, Sackler Institute of Psychobiological Research, Glasgow (United Kingdom); Champion, Sue [University of Glasgow, Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life Sciences, Glasgow (United Kingdom); Tamagnan, Gilles [Institute for Neurodegenerative Disorders, New Haven, CT (United States); Stehouwer, Jeffrey S.; Goodman, Mark M. [Emory University, Department of Radiology and Imaging Sciences, Atlanta, GA (United States); Hadley, Donald M. [NHS Greater Glasgow and Clyde, Department of Neuro-Radiology, Institute of Neurological Sciences, Glasgow (United Kingdom); Pimlott, Sally L. [NHS Greater Glasgow and Clyde, West of Scotland Radionuclide Dispensary, Glasgow (United Kingdom)

2012-05-15

{sup 123}I-labelled mZIENT (2{beta}-carbomethoxy-3{beta}-(3'-((Z)-2-iodoethenyl)phenyl)nortropane) has been developed as a radioligand for the serotonin transporter. The aim of this preliminary study was to assess its whole-body biodistribution in humans and estimate dosimetry. Three healthy controls and three patients receiving selective serotonin reuptake inhibitor (SSRI) therapy for depression were included (two men, four women, age range 41-56 years). Whole-body imaging, brain SPECT imaging and blood and urine sampling were performed. Whole-body images were analysed using regions of interest (ROIs), time-activity curves were derived using compartmental analysis and dosimetry estimated using OLINDA software. Brain ROI analysis was performed to obtain specific-to-nonspecific binding ratios in the midbrain, thalamus and striatum. Initial high uptake in the lungs decreased in later images. Lower uptake was seen in the brain, liver and intestines. Excretion was primarily through the urinary system. The effective dose was estimated to be of the order of 0.03 mSv/MBq. The organ receiving the highest absorbed dose was the lower large intestine wall. Uptake in the brain was consistent with the known SERT distribution with higher specific-to-nonspecific binding in the midbrain, thalamus and striatum in healthy controls compared with patients receiving SSRI therapy. {sup 123}I-mZIENT may be a promising radioligand for imaging the serotonin transporters in humans with acceptable dosimetry. (orig.)

Distinct Neural-Functional Effects of Treatments With Selective Serotonin Reuptake Inhibitors, Electroconvulsive Therapy, and Transcranial Magnetic Stimulation and Their Relations to Regional Brain Function in Major Depression: A Meta-analysis.

Science.gov (United States)

Chau, David T; Fogelman, Phoebe; Nordanskog, Pia; Drevets, Wayne C; Hamilton, J Paul

2017-05-01

Functional neuroimaging studies have examined the neural substrates of treatments for major depressive disorder (MDD). Low sample size and methodological heterogeneity, however, undermine the generalizability of findings from individual studies. We conducted a meta-analysis to identify reliable neural changes resulting from different modes of treatment for MDD and compared them with each other and with reliable neural functional abnormalities observed in depressed versus control samples. We conducted a meta-analysis of studies reporting changes in brain activity (e.g., as indexed by positron emission tomography) following treatments with selective serotonin reuptake inhibitors (SSRIs), electroconvulsive therapy (ECT), or transcranial magnetic stimulation. Additionally, we examined the statistical reliability of overlap among thresholded meta-analytic SSRI, ECT, and transcranial magnetic stimulation maps as well as a map of abnormal neural function in MDD. Our meta-analysis revealed that 1) SSRIs decrease activity in the anterior insula, 2) ECT decreases activity in central nodes of the default mode network, 3) transcranial magnetic stimulation does not result in reliable neural changes, and 4) regional effects of these modes of treatment do not significantly overlap with each other or with regions showing reliable functional abnormality in MDD. SSRIs and ECT produce neurally distinct effects relative to each other and to the functional abnormalities implicated in depression. These treatments therefore may exert antidepressant effects by diminishing neural functions not implicated in depression but that nonetheless impact mood. We discuss how the distinct neural changes resulting from SSRIs and ECT can account for both treatment effects and side effects from these therapies as well as how to individualize these treatments. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Increasing brain serotonin corrects CO2 chemosensitivity in methyl-CpG-binding protein 2 (Mecp2)-deficient mice

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Toward, Marie A.; Abdala, Ana P.; Knopp, Sharon J.; Paton, Julian F. R.; Bissonnette, John M.

2013-01-01

Mice deficient in the transcription factor methyl-CpG-binding protein 2 (Mecp2), a mouse model of Rett syndrome, display reduced CO2 chemosensitivity, which may contribute to their breathing abnormalities. In addition, patients with Rett syndrome and male mice that are null for Mecp2 show reduced levels of brain serotonin (5-HT). Serotonin is known to play a role in central chemosensitivity, and we hypothesized that increasing the availability of 5-HT in this mouse model would improve their respiratory response to CO2. Here we determined the apnoeic threshold in heterozygous Mecp2-deficient female mice and examined the effects of blocking 5-HT reuptake on the CO2 response in Mecp2-null male mice. Studies were performed in B6.129P2(C)-Mecp2τm1.1Bird null males and heterozygous females. In an in situ preparation, seven of eight Mecp2-deficient heterozygous females showed arrest of phrenic nerve activity when arterial CO2 was lowered to 3%, whereas the wild-types maintained phrenic nerve amplitude at 53 ± 3% of maximal. In vivo plethysmography studies were used to determine CO2 chemosensitivity in null males. These mice were exposed sequentially to 1, 3 and 5% CO2. The percentage increase in minute ventilation in response to increased inspired CO2 was less in Mecp2−/y than in Mecp2+/y mice. Pretreatment with citalopram, a selective 5-HT reuptake inhibitor (2.5 mg kg−1 I.P.), 40 min prior to CO2 exposure, in Mecp2−/y mice resulted in an improvement in CO2 chemosensitivity to wild-type levels. These results suggest that decreased 5-HT in Mecp2-deficient mice reduces CO2 chemosensitivity, and restoring 5-HT levels can reverse this effect. PMID:23180809

Molecular basis for selective serotonin reuptake inhibition by the antidepressant agent fluoxetine (prozac)

DEFF Research Database (Denmark)

Andersen, Jacob; Stuhr-Hansen, Nicolai; Zachariassen, Linda Grønborg

2014-01-01

X-ray crystal structures of LeuBAT, an engineered monoamine-like version of the bacterial amino acid transporter LeuT. However, the binding orientation of fluoxetine is reversed in our experimentally supported model compared with the LeuBAT structures, emphasizing the need for careful experimental...

β-cell serotonin production is associated with female sex, old age, and diabetes-free condition.

Science.gov (United States)

Kim, Yeong Gi; Moon, Joon Ho; Kim, Kyuho; Kim, Hyeongseok; Kim, Juok; Jeong, Ji-Seon; Lee, Junguee; Kang, Shinae; Park, Joon Seong; Kim, Hail

2017-11-25

Serotonin is known to be present in pancreatic β-cells and to play several physiological roles, including insulin secretion, β-cell proliferation, and paracrine inhibition of α-cells. However, the serotonin production of different cell lines and islets has not been compared based on age, sex, and diabetes related conditions. Here, we directly compared the serotonin concentrations in βTC and MIN6 cell lines, as well as in islets from mice using ultra-performance liquid chromatography tandem mass spectrometry. The average serotonin concentration was 5-10 ng/mg protein in the islets of male and non-pregnant female mice. The serotonin level was higher in females than males at 8 weeks, although there was no difference at 1 year. Furthermore, we observed serotonin by immunofluorescence staining in the pancreatic tissues of mice and human. Serotonin was detected by immunofluorescence staining in a portion of β-cells from islets of old female mice, but not of male or young female mice. A similar pattern was observed in human pancreas as well. In humans, serotonin production in β-cells was associated with a diabetes-free condition. Thus, serotonin production in β-cells was associated with old age, female sex, and diabetes-free condition. Copyright © 2017 Elsevier Inc. All rights reserved.

Selective Serotonin Reuptake Inhibitors (SSRIs)

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... and a rapid heart rate. Seek immediate medical attention if you have any of these signs or symptoms. Antidepressants and pregnancy. Talk to your doctor about the risks and benefits of using specific antidepressants. Some antidepressants may harm ...

Comparative Evaluation of Serotonin Toxicity among Veterans Affairs Patients Receiving Linezolid and Vancomycin

Science.gov (United States)

Patel, N.; Rivera, A.; Tristani, L.; Lazariu, V.; Vandewall, H.; McNutt, L. A.

2013-01-01

Despite the theoretical risk of serotonin toxicity (ST) with linezolid, “real-world” clinical evaluations of the risk of ST in patients receiving linezolid have been limited to case reports and noncomparator studies. An observational, matched-cohort study was conducted to evaluate the risk of ST among hospitalized patients who received linezolid or vancomycin at the Upstate New York Veterans Affairs Healthcare Network (Veterans Integrated Service Network 2 [VISN-2]). Matching criteria included VISN-2 hospital, hospital ward, prior hospital length of stay, age, and baseline platelet counts. The patients' electronic medical records were evaluated for symptoms consistent with ST and the Hunter serotonin toxicity criteria (HSTC) using an intensive, natural word search algorithm. The study included 251 matched pairs. Demographics and comorbidities were similar between groups. Over half of the study population received at least one concurrent medication with serotonergic activity. Receipt of agents with serotonergic activity was more pronounced in the vancomycin group, and the higher frequency was due to concomitant antihistamine and antiemetic use. Antidepressant use, including selective serotonin reuptake inhibitors (SSRIs), was similar between groups. No patients in either group were found to meet the criteria using the word search algorithm for ST. Fewer linezolid patients than vancomycin patients met the HSTC overall (3.2% versus 8.8%) and when stratified by receipt of a concurrent serotonergic agent (4.3% versus 12.4%). Of the patients meeting the HSTC, most had past or present comorbidities that may have contributed to or overlapped the HSTC. This study of hospitalized patients revealed comparably low frequencies of adverse events potentially related to ST among patients who received linezolid or vancomycin. PMID:24041888

Dapoxetine: An Innovative Approach in the Therapeutic Management In Animal Model of Depression

Directory of Open Access Journals (Sweden)

Hira Rafi

2016-01-01

Full Text Available Stress is a complicated condition that effects on person’s mental and physical health, and it is the precursor of other psychological disorders mainly depression. Serotonin (5-Hydroxytryptamine; 5-HT is well known to have hypofunction in unpredictable chronic mild stress whereas, unpredictable chronic mild stress (UCMS has produced the most steady and continuous results of anhedonia and learned helplessness particularly in rats. The stress-induced depressive like behavior can be reversed by many antidepressants such as SSRIs. Selective serotonin [5-hydroxytryptamine (5-HT] reuptake inhibitors (SSRIs is mostly prescribed antidepressant that can deplete neurochemical and behavioral deficits. The present study was designed to investigate whether repeated administration of dapoxetine at dose (1.0 mg/kg could reverse the behavioral deficits induced by UCMS in rat model of depression. UCMS induced behavioral deficits. Locomotor  activity in familiar environment (home cage, novel (open field environment and anxiolytic behavior in light/dark activity box were greater in unstressed group than stressed group. The inhibition of serotonin reuptake at pre-synaptic receptors by repeated dapoxetine administration is mainly the mechanism involved and discussed. This particular study may assist in novel approach for understanding the interaction between stress and behavioral functions and extending the therapeutic use of dapoxetine.

Characterization of intracellular regions in the human serotonin transporter for phosphorylation sites

DEFF Research Database (Denmark)

Sørensen, Lena; Strømgaard, Kristian; Kristensen, Anders S

2014-01-01

In the central nervous system, synaptic levels of the monoamine neurotransmitter serotonin are mainly controlled by the serotonin transporter (SERT), and drugs used in the treatment of various psychiatric diseases have SERT as primary target. SERT is a phosphoprotein that undergoes phosphorylation....../dephosphorylation during transporter regulation by multiple pathways. In particular, activation and/or inhibition of kinases including PKC, PKG, p38MAPK, and CaMKII modulate SERT function and trafficking. The molecular mechanisms by which kinase activity is linked to SERT regulation are poorly understood, including...

The association study between the interaction of serotonin and norepinephrine transporter gene polymorphisms and the effects of selective serotonin reuptake inhibitors%5-羟色胺和去甲肾上腺素转运体基因多态性的交互作用与重性抑郁障碍临床疗效的关联研究

Institute of Scientific and Technical Information of China (English)

孟亚琴; 孙宁; 王彦芳; 段慧君; 李素萍; 彭菊意; 杜巧荣; 张克让

2013-01-01

Objective To explore the relevance of the interaction of serotonin and norepinephrine transporter gene polymorphisms and the effects of selective serotonin reuptake inhibitors.Methods The subjects comprised 246 patients according to the diagnostic and statistical manual of mental disorders in the fourth edition (DSM-Ⅳ) criterion for major depressive disorder(MDD).The clinical efficacy were assessed by using 17 Hamilton depression quantity (HAMD) scale after selective serotonin reuptake inhibitors(SSRIs) citalopram (20 to 60 mg/d) or paroxetine (20 to 60 mg/d) were used randomly for 1,2,4,6 weeks.Polymerase chain reaction(PCR),sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE)and DNA sequencing analysis were used to detect the genotype of 5-HTT gene single nucleotide polymorphisms (SNP) of VNTR and LPR and SNPs at rs2242446 and rs5569 of NET.SPSS13.0 software were used for statistical analysis.Results (1) An association between 5-HTT LPR and the efficacy of SSRIs was found after 6 weeks in these samples (P =0.023).The clinical efficiency of LL genotype was higher than SS + LS genotype(OR =2.225,OR 95％ CI=1.118,4.427).(2) The interaction of 5-HTT LPR and NET rs5569 and the SSRIs antidepressant effects was statistical significance (P =0.01).Conclusion Preliminary study found that the interaction of 5-HTT LPR and NET rs5569 may be related to SSRIs antidepressant effects in China' s patients with MDD.%目的 探讨5-羟色胺和去甲肾上腺素转运体基因多态性的交互作用与选择性5-羟色胺再摄取抑制剂临床疗效的关联研究.方法 收集符合美国精神障碍诊断与统计手册第四版(DSM-Ⅳ)重性抑郁障碍(MDD)诊断标准的患者246例,给予选择性5-羟色胺再摄取抑制剂(SSRIs)西酞普兰(20～ 60mg/d)或帕罗西汀(20 ～ 60 mg/d),在治疗后1,2,4,6周运用17�

On the role of serotonin and histamine in neurohumoral mechanisms of postirradiation diarrhea in rats

International Nuclear Information System (INIS)

Legeza, V.I.; Shagoyan, M.G.; Markovskaya, I.V.; Vasil'eva, T.P.; Pozharisskaya, T.D.; Alekseeva, I.I.; Lokteva, O.I.

1990-01-01

In experiments with rats exposed to 200 Gy radiation it was shown that the diarrhea effect of serotonin under the effect of radiation is implemented via D- and M-type receptors, and that of histamine via H 1 and H 2 receptors. Serotonin and histamine, that were released under the effect of radiation from endocrine and mast cells of the digestive tract stimulated the propulsion activity of the intestine whereas histamine, in addition, inhibited the absorption process. It is suggested that serotonin and histamine antagonists should be used as means of preventing of radiation-induced diarrhea

Chronic blockade or constitutive deletion of the serotonin transporter reduces operant responding for food reward.

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Sanders, Amy Cecilia; Hussain, Ali J; Hen, René; Zhuang, Xiaoxi

2007-11-01

The therapeutic effects of chronic selective serotonin reuptake inhibitors (SSRIs) are well documented, yet the elementary behavioral processes that are affected by such treatment have not been fully investigated. We report here the effects of chronic fluoxetine treatment and genetic deletion of the serotonin transporter (SERT) on food reinforced behavior in three paradigms: the progressive ratio operant task, the concurrent choice operant task, and the Pavlovian-to-Instrumental transfer task. We consistently find that chronic pharmacological blockade or genetic deletion of SERT result in similar behavioral consequences: reduced operant responding for natural reward. This is in line with previous studies reporting declines in operant responding for drugs and intracranial self-stimulation with fluoxetine treatment, suggesting that the effect of SERT blockade can be generalized to different reward types. Detailed analyses of behavioral parameters indicate that this reduction in operant responding affect both goal-directed and non-goal-directed behaviors without affecting the Pavlovian cue-triggered excessive operant responding. In addition, both pharmacological and genetic manipulations reduce locomotor activity in the open field novel environment. Our data contrast with the effect of dopamine in increasing operant responding for natural reward specifically in goal-directed behaviors and in increasing Pavlovian cue-triggered excessive operant responding. Serotonin and dopamine have been proposed to serve opposing functions in motivational processes. Our data suggest that their interactions do not result in simple opponency. The fact that pharmacological blockade and genetic deletion of SERT have similar behavioral consequences reinforces the utility of the SERT null mice for investigation of the mechanisms underlying chronic SSRIs treatment.

FLUOXETINE INHIBITS OSTEOBLAST DIFFERENTIATION & MINERALIZATION IN FRACTURE HEALING

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Bradaschia-Correa, Vivian; Josephson, Anne M; Mehta, Devan; Mizrahi, Matthew; Neibart, Shane S; Liu, Chao; Kennedy, Oran; Castillo, Alesha B; Egol, Kenneth A; Leucht, Philipp

2016-01-01

Chronic use of selective serotonin reuptake inhibitors (SSRIs) for the treatment of depression has been linked to osteoporosis. In this study, we investigated the effect of chronic SSRI use on fracture healing in two murine models of bone regeneration. First, we performed a comprehensive analysis of endochondral bone healing in a femur fracture model. C57/BL6 mice treated with fluoxetine, the most commonly prescribed SSRI, developed a normal cartilaginous soft-callus at 14 days after fracture and demonstrated a significantly smaller and biomechanically weaker bony hard-callus at 28 days. In order to further dissect the mechanism that resulted in a smaller bony regenerate, we used an intramembranous model of bone healing and revealed that fluoxetine treatment resulted in a significantly smaller bony callus at 7 and 14 days postinjury. In order to test whether the smaller bony regenerate following fluoxetine treatment was caused by an inhibition of osteogenic differentiation and/or mineralization, we employed in vitro experiments, which established that fluoxetine treatment decreases osteogenic differentiation and mineralization and that this effect is serotonin-independent. Finally, in a translational approach, we tested whether cessation of the medication would result in restoration of the regenerative potential. However, histologic and µCT analysis revealed non-union formation in these animals with fibrous tissue interposition within the callus. In conclusion, fluoxetine exerts a direct, inhibitory effect on osteoblast differentiation and mineralization, shown in two disparate murine models of bone repair. Discontinuation of the drug did not result in restoration of the healing potential, but rather led to complete arrest of the repair process. Besides the well-established effect of SSRIs on bone homeostasis, our study provides strong evidence that fluoxetine use negatively impacts fracture healing. PMID:27869327

The association between lifting an administrative restriction on antidepressant dispensing and treatment patterns in Iceland

DEFF Research Database (Denmark)

Thengilsdottir, G; Gardarsdottir, H; Almarsdóttir, Anna Birna

2013-01-01

On March 1st 2009, restrictions on the dispensing of selective serotonin reuptake inhibitors (SSRI) in Iceland were lifted. Incident rates and changes in early discontinuation and switching before and after the change were investigated.......On March 1st 2009, restrictions on the dispensing of selective serotonin reuptake inhibitors (SSRI) in Iceland were lifted. Incident rates and changes in early discontinuation and switching before and after the change were investigated....

Deletion of the serotonin transporter in rats disturbs serotonin homeostasis without impairing liver regeneration.

NARCIS (Netherlands)

Matondo, R.B.; Punt, C.J.A.; Homberg, J.R.; Toussaint, M.J.; Kisjes, R.; Korporaal, S.J.; Akkerman, J.W.; Cuppen, E.; Bruin, A. de

2009-01-01

The serotonin transporter is implicated in the uptake of the vasoconstrictor serotonin from the circulation into the platelets, where 95% of all blood serotonin is stored and released in response to vascular injury. In vivo studies indicated that platelet-derived serotonin mediates liver

Deletion of the serotonin transporter in rats disturbs serotonin homeostasis without impairing liver regeneration

NARCIS (Netherlands)

Matondo, R.B.; Punt, C.; Homberg, J.R.; Toussaint, M.J.; Kisjes, R.; Korporaal, S.J.; Akkerman, J.W.; Cuppen, E.; de Bruin, A.

2009-01-01

The serotonin transporter is implicated in the uptake of the vasoconstrictor serotonin from the circulation into the platelets, where 95% of all blood serotonin is stored and released in response to vascular injury. In vivo studies indicated that platelet-derived serotonin mediates liver

Effects of fluoxetine on human embryo development

NARCIS (Netherlands)

Kaihola, Helena; Yaldir, Fatma G.; Hreinsson, Julius; Hornaeus, Katarina; Bergquist, Jonas; Olivier, Jocelien D. A.; Akerud, Helena; Sundstrom-Poromaa, Inger

2016-01-01

The use of antidepressant treatment during pregnancy is increasing, and selective serotonin reuptake inhibitors (SSRIs) are the most widely prescribed antidepressants in pregnant women. Serotonin plays a role in embryogenesis, and serotonin transporters are expressed in two-cell mouse embryos. Thus,

Exercise and sleep in aging: emphasis on serotonin.

Science.gov (United States)

Melancon, M O; Lorrain, D; Dionne, I J

2014-10-01

Reductions in central serotonin activity with aging might be involved in sleep-related disorders in later life. Although the beneficial effects of aerobic exercise on sleep are not new, sleep represents a complex recurring state of unconsciousness involving many lines of transmitters which remains only partly clear despite intense ongoing research. It is known that serotonin released into diencephalon and cerebrum might play a key inhibitory role to help promote sleep, likely through an active inhibition of supraspinal neural networks. Several lines of evidence support the stimulatory effects of exercise on higher serotonergic pathways. Hence, exercise has proved to elicit acute elevations in forebrain serotonin concentrations, an effect that waned upon cessation of exercise. While adequate exercise training might lead to adaptations in higher serotonergic networks (desensitization of forebrain receptors), excessive training has been linked to serious brain serotonergic maladaptations accompanied by insomnia. Dietary supplementation of tryptophan (the only serotonin precursor) is known to stimulate serotonergic activity and promote sleep, whereas acute tryptophan depletion causes deleterious effects on sleep. Regarding sleep-wake regulation, exercise has proved to accelerate resynchronization of the biological clock to new light-dark cycles following imposition of phase shifts in laboratory animals. Noteworthy, the effect of increased serotonergic transmission on wake state appears to be biphasic, i.e. promote wake and thereafter drowsiness. Therefore, it might be possible that acute aerobic exercise would act on sleep by increasing activity of ascending brain serotonergic projections, though additional work is warranted to better understand the implication of serotonin in the exercise-sleep axis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Selective labeling of serotonin uptake sites in rat brain by [3H]citalopram contrasted to labeling of multiple sites by [3H]imipramine

International Nuclear Information System (INIS)

D'Amato, R.J.; Largent, B.L.; Snowman, A.M.; Snyder, S.H.

1987-01-01

Citalopram is a potent and selective inhibitor of neuronal serotonin uptake. In rat brain membranes [ 3 H]citalopram demonstrates saturable and reversible binding with a KD of 0.8 nM and a maximal number of binding sites (Bmax) of 570 fmol/mg of protein. The drug specificity for [ 3 H]citalopram binding and synaptosomal serotonin uptake are closely correlated. Inhibition of [ 3 H]citalopram binding by both serotonin and imipramine is consistent with a competitive interaction in both equilibrium and kinetic analyses. The autoradiographic pattern of [ 3 H]citalopram binding sites closely resembles the distribution of serotonin. By contrast, detailed equilibrium-saturation analysis of [ 3 H]imipramine binding reveals two binding components, i.e., high affinity (KD = 9 nM, Bmax = 420 fmol/mg of protein) and low affinity (KD = 553 nM, Bmax = 8560 fmol/mg of protein) sites. Specific [ 3 H]imipramine binding, defined as the binding inhibited by 100 microM desipramine, is displaced only partially by serotonin. Various studies reveal that the serotonin-sensitive portion of binding corresponds to the high affinity sites of [ 3 H]imipramine binding whereas the serotonin-insensitive binding corresponds to the low affinity sites. Lesioning of serotonin neurons with p-chloroamphetamine causes a large decrease in [ 3 H]citalopram and serotonin-sensitive [ 3 H]imipramine binding with only a small effect on serotonin-insensitive [ 3 H]imipramine binding. The dissociation rate of [ 3 H]imipramine or [ 3 H]citalopram is not altered by citalopram, imipramine or serotonin up to concentrations of 10 microM. The regional distribution of serotonin sensitive [ 3 H]imipramine high affinity binding sites closely resembles that of [ 3 H]citalopram binding

Immunodetection of the serotonin transporter protein is a more valid marker for serotonergic fibers than serotonin

DEFF Research Database (Denmark)

Nielsen, Kirsten; Brask, Dorthe; Knudsen, Gitte M.

2006-01-01

Tracking serotonergic pathways in the brain through immunodetection of serotonin has widely been used for the anatomical characterization of the serotonergic system. Immunostaining for serotonin is also frequently applied for the visualization of individual serotonin containing fibers...... and quantification of serotonin positive fibers has been widely used to detect changes in the serotonergic innervation. However, particularly in conditions with enhanced serotonin metabolism the detection level of serotonin may lead to an underestimation of the true number of serotonergic fibers. The serotonin...... immunostained for serotonin and SERT protein and colocalization was quantified in several brain areas by confocal microscopy. In comparison with untreated rats, MAO inhibitor treated rats had a significantly higher number (almost 200% increase) of serotonin immunopositive fibers whereas no difference...

A Single Pair of Serotonergic Neurons Counteracts Serotonergic Inhibition of Ethanol Attraction in Drosophila.

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Xu, Li; He, Jianzheng; Kaiser, Andrea; Gräber, Nikolas; Schläger, Laura; Ritze, Yvonne; Scholz, Henrike

2016-01-01

Attraction to ethanol is common in both flies and humans, but the neuromodulatory mechanisms underlying this innate attraction are not well understood. Here, we dissect the function of the key regulator of serotonin signaling-the serotonin transporter-in innate olfactory attraction to ethanol in Drosophila melanogaster. We generated a mutated version of the serotonin transporter that prolongs serotonin signaling in the synaptic cleft and is targeted via the Gal4 system to different sets of serotonergic neurons. We identified four serotonergic neurons that inhibit the olfactory attraction to ethanol and two additional neurons that counteract this inhibition by strengthening olfactory information. Our results reveal that compensation can occur on the circuit level and that serotonin has a bidirectional function in modulating the innate attraction to ethanol. Given the evolutionarily conserved nature of the serotonin transporter and serotonin, the bidirectional serotonergic mechanisms delineate a basic principle for how random behavior is switched into targeted approach behavior.

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development and validation of stability indicating method for the quantitative determination of venlafaxine hydrochloride in extended release formulation using high performance liquid chromatography

Directory of Open Access Journals (Sweden)

Jaspreet Kaur

2010-01-01

Full Text Available Objective : Venlafaxine,hydrochloride is a structurally novel phenethyl bicyclic antidepressant, and is usually categorized as a serotonin-norepinephrine reuptake inhibitor (SNRI but it has been referred to as a serotonin-norepinephrine-dopamine reuptake inhibitor. It inhibits the reuptake of dopamine. Venlafaxine HCL is widely prescribed in the form of sustained release formulations. In the current article we are reporting the development and validation of a fast and simple stability indicating, isocratic high performance liquid chromatographic (HPLC method for the determination of venlafaxine hydrochloride in sustained release formulations. Materials and Methods : The quantitative determination of venlafaxine hydrochloride was performed on a Kromasil C18 analytical column (250 x 4.6 mm i.d., 5 μm particle size with 0.01 M phosphate buffer (pH 4.5: methanol (40: 60 as a mobile phase, at a flow rate of 1.0 ml/min. For HPLC methods, UV detection was made at 225 nm. Results : During method validation, parameters such as precision, linearity, accuracy, stability, limit of quantification and detection and specificity were evaluated, which remained within acceptable limits. Conclusions : The method has been successfully applied for the quantification and dissolution profiling of Venlafaxine HCL in sustained release formulation. The method presents a simple and reliable solution for the routine quantitative analysis of Venlafaxine HCL.

In vivo imaging of serotonin transporter occupancy by means of SPECT and [123I]ADAM in healthy subjects administered different doses of escitalopram or citalopram.

Science.gov (United States)

Klein, N; Sacher, J; Geiss-Granadia, T; Attarbaschi, T; Mossaheb, N; Lanzenberger, R; Pötzi, C; Holik, A; Spindelegger, C; Asenbaum, S; Dudczak, R; Tauscher, J; Kasper, S

2006-10-01

Escitalopram is a dual serotonin reuptake inhibitor (SSRI) approved for the treatment of depression and anxiety disorders. It is the S-enantiomer of citalopram, and is responsible for the serotonin reuptake activity, and thus for its pharmacological effects. Previous studies pointed out that clinically efficacious doses of other SSRIs produce an occupancy of the serotonin reuptake transporter (SERT) of about 80% or more. The novel radioligand [123I]ADAM and single photon emission computer tomography (SPECT) were used to measure midbrain SERT occupancies for different doses of escitalopram and citalopram. Twenty-five healthy subjects received a single dose of escitalopram [5 mg (n=5), 10 mg (n=5), and 20 mg (n=5)] or citalopram [(10 mg (n=5) and 20 mg (n=5)]. Midbrain SERT binding was measured with [(123)I]ADAM and SPECT on two study days, once without study drug and once 6 h after single dose administration of the study drug. The ratio of midbrain-cerebellum/cerebellum was the outcome measure (V3") for specific binding to SERT in midbrain. Subsequently, SERT occupancy levels were calculated using the untreated baseline level for each subject. An Emax model was used to describe the relationship between S-citalopram concentrations and SERT occupancy values. Additionally, four subjects received placebo to determine test-retest variability. Single doses of 5, 10, or 20 mg escitalopram led to a mean SERT occupancy of 60+/-6, 64+/-6, and 75+/-5%, respectively. SERT occupancies for subjects treated with single doses of 10 and 20 mg citalopram were 65+/-10 and 70+/-6%, respectively. A statistically significant difference was found between SERT occupancies after application of 10 and 20 mg escitalopram, but not for 10 and 20 mg citalopram. There was no statistically significant difference between the SERT occupancies of either 10 mg citalopram or 10 mg escitalopram, or between 20 mg citalopram and 20 mg escitalopram. Emax was slightly higher after administration of

MS-377, a novel selective sigma(1) receptor ligand, reverses phencyclidine-induced release of dopamine and serotonin in rat brain.

Science.gov (United States)

Takahashi, S; Horikomi, K; Kato, T

2001-09-21

A novel selective sigma(1) receptor ligand, (R)-(+)-1-(4-chlorophenyl)-3-[4-(2-methoxyethyl)piperazin-1-yl]methyl-2-pyrrolidinone L-tartrate (MS-377), inhibits phencyclidine (1-(1-phenylcyclohexyl)piperidine; PCP)-induced behaviors in animal models. In this study, we measured extracellular dopamine and serotonin levels in the rat brain after treatment with MS-377 alone, using in vivo microdialysis. We also examined the effects of MS-377 on extracellular dopamine and serotonin levels in the rat medial prefrontal cortex after treatment with PCP. MS-377 itself had no significant effects on dopamine release in the striatum (10 mg/kg, p.o.) nor on dopamine or serotonin release in the medial prefrontal cortex (1 and 10 mg/kg, p.o.). PCP (3 mg/kg, i.p.) markedly increased dopamine and serotonin release in the medial prefrontal cortex. MS-377 (1 mg/kg, p.o.), when administered 60 min prior to PCP, significantly attenuated this effect of PCP. These results suggest that the inhibitory effects of MS-377 on PCP-induced behaviors are partly mediated by inhibition of the increase in dopamine and serotonin release in the rat medial prefrontal cortex caused by PCP.

A naturalistic long-term comparison study of selective serotonin reuptake inhibitors in the treatment of panic disorder.

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Dannon, Pinhas N; Iancu, Iulian; Lowengrub, Katherine; Gonopolsky, Yehudit; Musin, Ernest; Grunhaus, Leon; Kotler, Moshe

2007-01-01

Selective serotonin reuptake inhibitors (SSRIs) are currently considered as the first drug of choice in the treatment of panic disorder (PD). The aim of this long-term, naturalistic comparison study was to compare 4 SSRIs with respect to tolerability and treatment outcome of PD. Outcome measures included relapse rates and adverse effects. Two hundred patients with PD were enrolled in our study. All subjects met DSM-IV criteria for PD or PD with agoraphobia (PDA). All patients were assigned to receive SSRI monotherapy for 12 months with either citalopram (n = 50), fluoxetine (n = 50), fluvoxamine (n = 50), or paroxetine (n = 50) in a randomized, nonblinded fashion. Both the treating psychiatrist and the patients were not blind to the assigned treatment, but the clinician raters were blind to the study medication. The study design allowed for assignment of a particular SSRI as indicated according to the clinical judgment of the study psychiatrists. The Panic Self-Questionnaire, which is a self-report scale, was administered at baseline and then once per month during the duration of the 12-month study. The visual analog scale and the Clinical Global Impression Scale were administered at baseline and then once per month during the period of the study. Reports of sexual dysfunction were assessed using a nonstructured clinical interview at monthly visits. The body weight of study subjects was measured at baseline, and then at the 12th month visit end point. Of 200 patients who entered the study, 127 patients (63.5%) completed the full 12-month protocol. Retention rates were highest for paroxetine (76% [38/50]), intermediate for citalopram (68% [34/50]) and fluvoxamine (60% [30/50]), and lowest for fluoxetine (50% [25/50]). Patients who completed the 12-month protocol responded favorably to the study treatment. The paroxetine and the citalopram groups had significantly lower rates of panic symptoms as measured at visits on weeks 4 and 8. At visits on months 3, 6, 9, and

A new Drosophila octopamine receptor responds to serotonin.

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Qi, Yi-Xiang; Xu, Gang; Gu, Gui-Xiang; Mao, Fen; Ye, Gong-Yin; Liu, Weiwei; Huang, Jia

2017-11-01

As the counterparts of the vertebrate adrenergic transmitters, octopamine and tyramine are important physiological regulators in invertebrates. They control and modulate many physiological and behavioral functions in insects. In this study, we reported the pharmacological properties of a new α2-adrenergic-like octopamine receptor (CG18208) from Drosophila melanogaster, named DmOctα2R. This new receptor gene encodes two transcripts by alternative splicing. The long isoform DmOctα2R-L differs from the short isoform DmOctα2R-S by the presence of an additional 29 amino acids within the third intracellular loop. When heterologously expressed in mammalian cell lines, both receptors were activated by octopamine, tyramine, epinephrine and norepinephrine, resulting in the inhibition of cAMP production in a dose-dependent manner. The long form is more sensitive to the above ligands than the short form. The adrenergic agonists naphazoline, tolazoline and clonidine can stimulate DmOctα2R as full agonists. Surprisingly, serotonin and serotoninergic agonists can also activate DmOctα2R. Several tested adrenergic antagonists and serotonin antagonists blocked the action of octopamine or serotonin on DmOctα2R. The data presented here reported an adrenergic-like G protein-coupled receptor activated by serotonin, suggesting that the neurotransmission and neuromodulation in the nervous system could be more complex than previously thought. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemoreactomic analysis of thiamine disulfide, thiamine hydrochloride, and benfotiamine molecules

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O. A. Gromova

2017-01-01

Full Text Available Objective: to analyze the interactions that could indicate the potential pharmacological properties of the molecules of thiamin, thiamine disulfide, and others.Material and methods. The investigators simulated the properties of thiamine disulfide (bistiamin versus those of the reference molecules of thiamin hydrochloride and benfotiamine. The study was performed using chemoreactomic simulation that is the newest area in post-genome pharmacology.Results and discussion. Chemoreactomic analysis has shown that thiamine disulfide can inhibit the molecular receptors involved in blood pressure regulation: adrenoceptors, vasopressin receptor, and angiotensin receptor. Thiamine disulfide can inhibit the reuptake of serotonin, increase its levels, inhibit benzodiazepine receptor and dopamine reuptake, and enhance neuronal acetylcholine release to a large extent than benfotiamine. These molecular effects are consistent with the sedative and anticonvulsant action profile of thiamine disulfide. Simulation has indicated that thiamine disulfide has neuroprotective, anti-inflammatory, normolipidemic, and antitumor activities.Conclusion. The simulation results are confirmed by the available clinical and experimental findings and indicate the virtually unstudied molecular mechanisms of action of thiamine disulfide, benfotiamine, and thiamin hydrochloride. 

The noradrenergic symptom cluster: clinical expression and neuropharmacology

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Blier P

2011-06-01

Full Text Available Pierre Blier1, Mike Briley21Institute of Mental Health Research, University of Ottawa, Ottawa, Ontario, Canada; 2NeuroBiz Consulting and Communication, Castres, FranceAbstract: Signs and symptoms of depression can be linked to one or more monoaminergic systems, specifically the norepinephrine (NE, the dopamine (DA, and the serotonin (5-HT systems. In particular, the modulation of energy, vigilance, and arousal can be directly linked to the NE system. There is, however, a great deal of overlap in the modulation of the symptoms of depression between these monoaminergic systems. There are considerable reciprocal interactions between the NE, DA, and the 5-HT systems. When using a selective serotonin reuptake inhibitor (SSRI, for example, 5-HT transmission is enhanced, but at the same time there is a dampening of the activity of NE and DA neurons through inhibitory 5-HT2A and 5-HT2C receptors, respectively. This could explain the residual symptoms of fatigue, lack of energy, and anhedonia, often seen after patients present an overall positive response to a SSRI. Using a dual 5-HT and NE reuptake inhibitor (SNRI, such as milnacipran, would result in an additional increase in NE activity. Futhermore, inhibiting NE reuptake increases DA availability in the frontal cortex since DA is mainly cleared by the NE transporters in several brain regions. A risk inherent in increased NE activity is that of provoking anxiety. This is avoided however by the attenuation of the phasic reactivity of the firing of NE neurons through prolonged administration of SSRI and SNRI.Keywords: norepinephrine, dopamine, serotonin, residual symptoms, norepinephrine paradox

Radioactive cDNA microarray (II): Gene expression profiling of antidepressant treatment by human cDNA microarray

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Lee, Ji Hye; Kang, Rhee Hun; Ham, Byung Joo; Lee, Min Su; Shin, Kyung Ho; Choe, Jae Gol; Kim, Meyoung Kon [College of Medicine, Univ. of Korea, Seoul (Korea, Republic of)

2003-07-01

Major depressive disorder is a prevalent psychiatric disorder in primary care, associated with impaired patient functioning and well-being. Fluoxetine is a selective serotonin-reuptake inhibitors (SSRIs) and is a commonly prescribed antidepressant compound. Its action is primarily attributed to selective inhibition of the reuptake of serotonin (5-hydroxytryptamine) in the central nervous system. Objectives ; the aims of this study were two-fold: (1) to determine the usefulness for investigation of the transcription profiles in depression patients, and (2) to assess the differences in gene expression profiles between positive response group and negative response groups by fluoxetine treatment. This study included 53 patients with major depression (26 in positive response group with antidepressant treatment, 27 in negative response group with antidepressant treatment), and 53 healthy controls. To examine the difference of gene expression profile in depression patients, radioactive complementary DNA microarrays were used to evaluate changes in the expression of 1,152 genes in total. Using 33p-labeled probes, this method provided highly sensitive gene expression profiles including brain receptors, drug metabolism, and cellular signaling. Gene transcription profiles were classified into several categories in accordance with the antidepressant gene-regulation. The gene profiles were significantly up-(22 genes) and down-(16 genes) regulated in the positive response group when compared to the control group. Also, in the negative response group, 35 genes were up-regulated and 8 genes were down-regulated when compared to the control group. Consequently, we demonstrated that radioactive human cDNA microarray is highly likely to be an efficient technology for evaluating the gene regulation of antidepressants, such as selective serotonin-reuptake inhibitors (SSRIs), by using high-throughput biotechnology.

Radioactive cDNA microarray (II): Gene expression profiling of antidepressant treatment by human cDNA microarray

International Nuclear Information System (INIS)

Lee, Ji Hye; Kang, Rhee Hun; Ham, Byung Joo; Lee, Min Su; Shin, Kyung Ho; Choe, Jae Gol; Kim, Meyoung Kon

2003-01-01

Major depressive disorder is a prevalent psychiatric disorder in primary care, associated with impaired patient functioning and well-being. Fluoxetine is a selective serotonin-reuptake inhibitors (SSRIs) and is a commonly prescribed antidepressant compound. Its action is primarily attributed to selective inhibition of the reuptake of serotonin (5-hydroxytryptamine) in the central nervous system. Objectives ; the aims of this study were two-fold: (1) to determine the usefulness for investigation of the transcription profiles in depression patients, and (2) to assess the differences in gene expression profiles between positive response group and negative response groups by fluoxetine treatment. This study included 53 patients with major depression (26 in positive response group with antidepressant treatment, 27 in negative response group with antidepressant treatment), and 53 healthy controls. To examine the difference of gene expression profile in depression patients, radioactive complementary DNA microarrays were used to evaluate changes in the expression of 1,152 genes in total. Using 33p-labeled probes, this method provided highly sensitive gene expression profiles including brain receptors, drug metabolism, and cellular signaling. Gene transcription profiles were classified into several categories in accordance with the antidepressant gene-regulation. The gene profiles were significantly up-(22 genes) and down-(16 genes) regulated in the positive response group when compared to the control group. Also, in the negative response group, 35 genes were up-regulated and 8 genes were down-regulated when compared to the control group. Consequently, we demonstrated that radioactive human cDNA microarray is highly likely to be an efficient technology for evaluating the gene regulation of antidepressants, such as selective serotonin-reuptake inhibitors (SSRIs), by using high-throughput biotechnology

Serotonin Transporter Knockout Rats Show Improved Strategy Set-Shifting and Reduced Latent Inhibition

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Nonkes, Lourens J. P.; van de Vondervoort, Ilse I. G. M.; de Leeuw, Mark J. C.; Wijlaars, Linda P.; Maes, Joseph H. R.; Homberg, Judith R.

2012-01-01

Behavioral flexibility is a cognitive process depending on prefrontal areas allowing adaptive responses to environmental changes. Serotonin transporter knockout (5-HTT[superscript -/-]) rodents show improved reversal learning in addition to orbitofrontal cortex changes. Another form of behavioral flexibility, extradimensional strategy set-shifting…

High serotonin levels during brain development alter the structural input-output connectivity of neural networks in the rat somatosensory layer IV

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Stéphanie eMiceli

2013-06-01

Full Text Available Homeostatic regulation of serotonin (5-HT concentration is critical for normal topographical organization and development of thalamocortical (TC afferent circuits. Down-regulation of the serotonin transporter (SERT and the consequent impaired reuptake of 5-HT at the synapse, results in a reduced terminal branching of developing TC afferents within the primary somatosensory cortex (S1. Despite the presence of multiple genetic models, the effect of high extracellular 5-HT levels on the structure and function of developing intracortical neural networks is far from being understood. Here, using juvenile SERT knockout (SERT-/- rats we investigated, in vitro, the effect of increased 5-HT levels on the structural organization of (i the thalamocortical projections of the ventroposteromedial thalamic nucleus towards S1, (ii the general barrel-field pattern and (iii the electrophysiological and morphological properties of the excitatory cell population in layer IV of S1 (spiny stellate and pyramidal cells. Our results confirmed previous findings that high levels of 5-HT during development lead to a reduction of the topographical precision of TCA projections towards the barrel cortex. Also, the barrel pattern was altered but not abolished in SERT-/- rats. In layer IV, both excitatory spiny stellate and pyramidal cells showed a significantly reduced intracolumnar organization of their axonal projections. In addition, the layer IV spiny stellate cells gave rise to a prominent projection towards the infragranular layer Vb. Our findings point to a structural and functional reorganization, of TCAs, as well as early stage intracortical microcircuitry, following the disruption of 5-HT reuptake during critical developmental periods. The increased projection pattern of the layer IV neurons suggests that the intracortical network changes are not limited to the main entry layer IV but may also affect the subsequent stages of the canonical circuits of the barrel

A Network Meta-Analysis Comparing Effects of Various Antidepressant Classes on the Digit Symbol Substitution Test (DSST) as a Measure of Cognitive Dysfunction in Patients with Major Depressive Disorder.

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Baune, Bernhard T; Brignone, Mélanie; Larsen, Klaus Groes

2018-02-01

Major depressive disorder is a common condition that often includes cognitive dysfunction. A systematic literature review of studies and a network meta-analysis were carried out to assess the relative effect of antidepressants on cognitive dysfunction in major depressive disorder. MEDLINE, Embase, Cochrane, CDSR, and PsychINFO databases; clinical trial registries; and relevant conference abstracts were searched for randomized controlled trials assessing the effects of antidepressants/placebo on cognition. A network meta-analysis comparing antidepressants was conducted using a random effects model. The database search retrieved 11337 citations, of which 72 randomized controlled trials from 103 publications met the inclusion criteria. The review identified 86 cognitive tests assessing the effect of antidepressants on cognitive functioning. However, the Digit Symbol Substitution Test, which targets multiple domains of cognition and is recognized as being sensitive to change, was the only test that was used across 12 of the included randomized controlled trials and that allowed the construction of a stable network suitable for the network meta-analysis. The interventions assessed included selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and other non-selective serotonin reuptake inhibitors/serotonin-norepinephrine reuptake inhibitors. The network meta-analysis using the Digit Symbol Substitution Test showed that vortioxetine was the only antidepressant that improved cognitive dysfunction on the Digit Symbol Substitution Test vs placebo {standardized mean difference: 0.325 (95% CI = 0.120; 0.529, P=.009}. Compared with other antidepressants, vortioxetine was statistically more efficacious on the Digit Symbol Substitution Test vs escitalopram, nortriptyline, and the selective serotonin reuptake inhibitor and tricyclic antidepressant classes. This study highlighted the large variability in measures used to assess cognitive functioning

SEROTONIN METABOLISM FOLLOWING PLATINUM-BASED CHEMOTHERAPY COMBINED WITH THE SEROTONIN TYPE-3 ANTAGONIST TROPISETRON

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SCHRODER, CP; VANDERGRAAF, WTA; KEMA, IP; GROENEWEGEN, A; SLEIJFER, DT; DEVRIES, EGE

1995-01-01

The administration of platinum-based chemotherapy induces serotonin release from the enterochromaffin cells, causing nausea and vomiting. This study was conducted to evaluate parameters of serotonin metabolism following platinum-based chemotherapy given in combination with the serotonin type-3

Comparison of neurogenic effects of fluoxetine, duloxetine and running in mice

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Marlatt, M.W.; Lucassen, P.J.; van Praag, H.

2010-01-01

Hippocampal neurogenesis can be regulated by extrinsic factors, such as exercise and antidepressants. While there is evidence that the selective serotonin reuptake inhibitor (SSRI) fluoxetine enhances neurogenesis, the new dual serotonergic-noradrenergic reuptake inhibitor (SNRI) duloxetine has not

Emotional modulation of motor response inhibition in women with borderline personality disorder: an fMRI study.

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Jacob, Gitta A; Zvonik, Kerstin; Kamphausen, Susanne; Sebastian, Alexandra; Maier, Simon; Philipsen, Alexandra; Tebartz van Elst, Ludger; Lieb, Klaus; Tüscher, Oliver

2013-05-01

Both emotion regulation and impulsivity are core aspects of borderline personality disorder (BPD) pathology. Although both problems may be combined specifically in BPD, few studies to date have investigated the emotional modulation of impulsivity in BPD. Women with BPD and matched healthy controls performed go/no-go tasks after induction of anger, joy or a neutral mood by vocally presented short stories. Dependent variables were the behavioural results and functional magnetic resonance imaging data. We included 17 women with BPD and 18 controls in our study. No behavioural group differences were found. However, patients with BPD showed stronger activation of the left amygdala and weaker activation of the subgenual anterior cingulate during anger induction than controls. Inhibition in the go/no-go task after anger induction increased activity in the left inferior frontal cortex in controls, but not in women with BPD, who, in turn, showed increased activation in the subthalamic nucleus. Findings cannot be generalized to men, and 4 patients were taking antidepressant medication (selective serotonin reuptake inhibitors). In addition, no patient control group was investigated, thus we do not know whether findings are specific to BPD compared with other disorders. Our findings are consistent with the view that a disturbed amygdala-prefrontal network in patients with BPD is compensated by a subcortical loop involving the subthalamic nucleus, leading to normal behavioural inhibition in these patients.

Serotonin 1B Receptors Regulate Prefrontal Function by Gating Callosal and Hippocampal Inputs

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Kjaerby, Celia; Athilingam, Jegath; Robinson, Sarah E

2016-01-01

Both medial prefrontal cortex (mPFC) and serotonin play key roles in anxiety; however, specific mechanisms through which serotonin might act on the mPFC to modulate anxiety-related behavior remain unknown. Here, we use a combination of optogenetics and synaptic physiology to show that serotonin...... acts presynaptically via 5-HT1B receptors to selectively suppress inputs from the contralateral mPFC and ventral hippocampus (vHPC), while sparing those from mediodorsal thalamus. To elucidate how these actions could potentially regulate prefrontal circuit function, we infused a 5-HT1B agonist...... into the mPFC of freely behaving mice. Consistent with previous studies that have optogenetically inhibited vHPC-mPFC projections, activating prefrontal 5-HT1B receptors suppressed theta-frequency mPFC activity (4-12 Hz), and reduced avoidance of anxiogenic regions in the elevated plus maze. These findings...

The molecular mechanism for overcoming the rate-limiting step in monoamine neurotransmitter transport

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Sinning, Steffen; Said, Saida; Malinauskaite, Lina

The monoamine transporter family consists of dopamine (DAT), norepinephrine (NET) and serotonin transporters (SERT) that mediate the reuptake of the monoamine neurotransmitters after their release during neurotransmission. These transporters play prominent roles in psychiatric disorders and are t......The monoamine transporter family consists of dopamine (DAT), norepinephrine (NET) and serotonin transporters (SERT) that mediate the reuptake of the monoamine neurotransmitters after their release during neurotransmission. These transporters play prominent roles in psychiatric disorders...... membrane. The rate-limiting step in monoamine reuptake is the return of the empty transporter from an inward-facing to an outward-facing conformation without neurotransmitter and sodium bound. The molecular mechanism underlying this important conformational transition has not been described. Crystal...

Use of antidepressants and risk of epithelial ovarian cancer

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Mørch, Lina S; Dehlendorff, Christian; Baandrup, Louise

2017-01-01

antidepressants, selective serotonin reuptake inhibitors, other antidepressants, and potential confounder drugs), medical and reproductive history and socioeconomic parameters, were obtained from nationwide registries. We used conditional logistic regression models to estimate adjusted odds ratios (ORs) and two.......80 (95% CI, 0.60-1.08). Among postmenopausal women, the inverse association was restricted to users of menopausal hormone therapy. In conclusion, use of selective serotonin reuptake inhibitors was associated with a decreased risk of epithelial ovarian cancer; thereby implying potential chemopreventive...

Effects of milnacipran on binge eating – a pilot study

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Shun’ichi Noma

2008-03-01

Full Text Available Shun’ichi Noma1, Teruhisa Uwatoko1, Haruka Yamamoto2, Takuji Hayashi11Department of Psychiatry, Graduate School of Medicine, Kyoto University, Kyoto, Japan; 2Department of Psychiatry, Toyooka Hospital, Hyogo, JapanAbstract: Selective serotonin reuptake inhibitors and selective norepinephrine reuptake inhibitors are effective in the treatment of bulimia nervosa. There have been relatively few studies of the efficacy of specific serotonin and norepinephrine reuptake inhibitors in the treatment of eating disorders. Twenty-five outpatients with binge eating episodes, diagnosed as anorexia nervosa, binge-eating/purging type, bulimia nervosa/purging type, or bulimia nervosa/non-purging type, were treated with milnacipran and 20 patients completed the 8-week study. Symptom severity was evaluated using the Bulimic Investigatory Test, Edinburgh (BITE self-rating scale before administration of milnacipran and after 1, 4, and 8 weeks treatment. The scores improved after 8 weeks, especially drive to, and regret for, binge eating. Milnacipran was more effective in patients without purging and in younger patients, while there was no difference in the efficacy of milnacipran among subtypes of eating disorders.Keywords: milnacipran, specific serotonin and norepinephrine reuptake inhibitors, binge eating, vomiting, eating disorder, pharmacotherapy

Unexpected Formation of Naphtyl 1,3-Diaminopropane-2-ol Derivative through Azetidinium Ion Intermediate

International Nuclear Information System (INIS)

Han, Minsoo; Hahn, Hohgyu

2012-01-01

The cause of depression is commonly associated with a deficiency of monoamine neurotransmitters such as serotonin, norepinephrine and dopamine in the brain. Inhibition of monoamine reuptake has been an effective pharmacological treatment of various CNS disorders.1 As a part of our continuing efforts to develop novel antidepressants for multiple therapeutic utilities, we designed diaminopropan-2-ol 1 through structure analysis and molecular modification and of currently marketed reuptake transporter based antidepressants. 3-amino-1,2-diol derivatives 7 were converted to the corresponding diaminopropan-2-ol derivatives 9 by the reaction with MsCl in the presence of triethylamine followed by the treatment of either amine or thiol. We proposed azetdinium ion 11 or azetidinium ylide 12 as an intermediate in the reaction, and prepared 7 analogues by similar manner

Unexpected Formation of Naphtyl 1,3-Diaminopropane-2-ol Derivative through Azetidinium Ion Intermediate

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Han, Minsoo; Hahn, Hohgyu [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

2012-11-15

The cause of depression is commonly associated with a deficiency of monoamine neurotransmitters such as serotonin, norepinephrine and dopamine in the brain. Inhibition of monoamine reuptake has been an effective pharmacological treatment of various CNS disorders.1 As a part of our continuing efforts to develop novel antidepressants for multiple therapeutic utilities, we designed diaminopropan-2-ol 1 through structure analysis and molecular modification and of currently marketed reuptake transporter based antidepressants. 3-amino-1,2-diol derivatives 7 were converted to the corresponding diaminopropan-2-ol derivatives 9 by the reaction with MsCl in the presence of triethylamine followed by the treatment of either amine or thiol. We proposed azetdinium ion 11 or azetidinium ylide 12 as an intermediate in the reaction, and prepared 7 analogues by similar manner.

Disruption of Transient Serotonin Accumulation by Non-Serotonin-Producing Neurons Impairs Cortical Map Development

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Xiaoning Chen

2015-01-01

Full Text Available Polymorphisms that alter serotonin transporter SERT expression and functionality increase the risks for autism and psychiatric traits. Here, we investigate how SERT controls serotonin signaling in developing CNS in mice. SERT is transiently expressed in specific sets of glutamatergic neurons and uptakes extrasynaptic serotonin during perinatal CNS development. We show that SERT expression in glutamatergic thalamocortical axons (TCAs dictates sensory map architecture. Knockout of SERT in TCAs causes lasting alterations in TCA patterning, spatial organizations of cortical neurons, and dendritic arborization in sensory cortex. Pharmacological reduction of serotonin synthesis during the first postnatal week rescues sensory maps in SERTGluΔ mice. Furthermore, knockdown of SERT expression in serotonin-producing neurons does not impair barrel maps. We propose that spatiotemporal SERT expression in non-serotonin-producing neurons represents a determinant in early life genetic programming of cortical circuits. Perturbing this SERT function could be involved in the origin of sensory and cognitive deficits associated with neurodevelopmental disorders.

[Escitalopram and citalopram: the unexpected role of the R-enantiomer].

Science.gov (United States)

Jacquot, C; David, D J; Gardier, A M; Sánchez, C

2007-01-01

Citalopram, a selective serotonin reuptake inhibitor, is composed of 2 enantiomers, R-citalopram and S-citalopram, 2 different non-superimposable mirror image forms of the same molecule. Separating these 2 enantiomers has enabled studying their individual properties. Citalopram's pharmacologic activity is centered on the S enantiomer's high affinity for the serotonin transporter which is twice as high as citalopram's and 30 to 40 times higher than R-citalopram. This leads to an inhibition of serotonin reuptake two times higher for escitalopram compared with citalopram and confirms that citalopram's pharmacologic activity is due to the S-enantiomer. Contrary to what might be expected, the effect of escitalopram (DCI of S-citalopram) is not superimposable on an equivalent dose of citalopram but is superior. Several hypotheses could explain this superiority. First, conversions of the S-enantiomer into the R-enantiomer may occur, but there is no reason why this phenomenon would happen more when both enantiomers are present than when escitalopram is alone. Furthermore, pharmacokinetic studies have shown that S or R configurations are stable in vivo. Second, a particular action of R-citalopram may influence the S-enantiomer's kinetic from intestinal absorption to blood-brain barrier. But concentrations of both enantiomers in the frontal cortex are the same. Therefore, R-citalopram does not interfere with escitalopram's kinetic. Finally, interactions may appear at the synaptic level. Results of experimentation, after in situ injection to the cortex level, confirm that an interaction between the 2 enantiomers takes place at that level. A direct negative interaction of R-citalopram on one or several effectors that create the antidepressive effect seems justified. This negative interaction has been studied in depth. Animal models have shown that the R-enantiomer has no antidepressive potential and when associated with escitalopram prohedonic effects disappear. Escitalopram

Salivary serotonin does not correlate with central serotonin turnover in adult phenylketonuria (PKU patients

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Joseph Leung

2018-06-01

Full Text Available Introduction: Phenylketonuria (PKU is an inborn error of metabolism associated with an increased risk of behavioural and mood disorders. There are currently no reliable markers for monitoring mood in PKU. The purpose of this study was to evaluate salivary serotonin as a possible non-invasive marker of long-term mood symptoms and central serotonin activity in patients with PKU. Methods: 20 patients were recruited from our Adult Metabolic Diseases Clinic. Age, sex, plasma phenylalanine (Phe level, DASS (Depression Anxiety Stress Scales depression score, DASS anxiety score, BMI, salivary serotonin, salivary cortisol, 2-year average Phe, 2-year average tyrosine (Tyr, and 2-year average Phe:Tyr ratio were collected for each patient. Spearman's ρ correlation analysis was used to determine if there was any relationship between any of the parameters. Results: There were positive correlations between DASS anxiety and DASS depression scores (Spearman's ρ = 0.8708, p-value < 0.0001, BMI and plasma Phe level (Spearman's ρ = 0.6228, p-value = .0034, and 2-year average Phe and BMI (Spearman's ρ = 0.5448, p-value = .0130. There was also a negative correlation between salivary cortisol and plasma Phe level (Spearman's ρ = −0.5018, p-value = .0338. All other correlations were not statistically significant. Conclusion: Salivary serotonin does not correlate with peripheral phenylalanine levels, DASS depression scale scores, or DASS anxiety scale scores, implying that salivary serotonin does not reflect central serotonin turnover. Additionally, this study suggests that salivary serotonin is not a suitable marker for monitoring dietary control, mood, or anxiety in PKU. Synopsis: Salivary serotonin does not correlate with peripheral phenylalanine levels, DASS depression scale scores, or DASS anxiety scale scores, suggesting that salivary serotonin is not a suitable marker for monitoring dietary control, mood, or anxiety in PKU

The impact of peripheral serotonin on leptin-brain serotonin axis, bone metabolism and strength in growing rats with experimental chronic kidney disease.

Science.gov (United States)

Pawlak, Dariusz; Domaniewski, Tomasz; Znorko, Beata; Oksztulska-Kolanek, Ewa; Lipowicz, Paweł; Doroszko, Michał; Karbowska, Malgorzata; Pawlak, Krystyna

2017-12-01

Chronic kidney disease (CKD) results in decreased bone strength. Serotonin (5-HT) is one of the critical regulators of bone health, fulfilling distinct functions depending on its synthesis site: brain-derived serotonin (BDS) favors osteoblast proliferation, whereas gut-derived serotonin (GDS) inhibits it. We assessed the role of BDS and peripheral leptin in the regulation of bone metabolism and strength in young rats with 5/6 nephrectomy. BDS synthesis was accelerated during CKD progression. Decreased peripheral leptin in CKD rats was inversely related to BDS content in the hypothalamus, brainstem and frontal cortex. Serotonin in these brain regions affected bone strength and metabolism in the studied animals. The direct effect of circulating leptin on bone was not shown in uremia. At the molecular level, there was an inverse association between elevated GDS and the expression of cAMP responsive element-binding protein (Creb) gene in bone of CKD animals. In contrast, increased expression of activating transcription factor 4 (Atf4) was shown, which was associated with GDS-dependent transcription factor 1 (Foxo1), clock gene - Cry-1, cell cycle genes: c-Myc, cyclins, and osteoblast differentiation genes. These results identified a previously unknown molecular pathway, by which elevated GDS can shift in Foxo1 target genes from Creb to Atf4-dependent response, disrupting the leptin-BDS - dependent gene pathway in the bone of uremic rats. Thus, in the condition of CKD the effect of BDS and GDS on bone metabolism and strength can't be distinguished. Copyright © 2017 Elsevier Inc. All rights reserved.

Serotonin's Complex Role in Alcoholism: Implications for Treatment and Future Research.

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Marcinkiewcz, Catherine A; Lowery-Gionta, Emily G; Kash, Thomas L

2016-06-01

Current pharmacological treatments for alcohol dependence have focused on reducing alcohol consumption, but to date there are few treatments that also address the negative affective symptoms during acute and protracted alcohol withdrawal which are often exacerbated in people with comorbid anxiety and depression. Selective serotonin reuptake inhibitors (SSRIs) are sometimes prescribed to ameliorate these symptoms but can exacerbate anxiety and cravings in a select group of patients. In this critical review, we discuss recent literature describing an association between alcohol dependence, the SERT linked polymorphic region (5-HTTLPR), and pharmacological response to SSRIs. Given the heterogeneity in responsiveness to serotonergic drugs across the spectrum of alcoholic subtypes, we assess the contribution of specific 5-HT circuits to discrete endophenotypes of alcohol dependence. 5-HT circuits play a distinctive role in reward, stress, and executive function which may account for the variation in response to serotonergic drugs. New optogenetic and chemogenetic methods for dissecting 5-HT circuits in alcohol dependence may provide clues leading to more effective pharmacotherapies. Although our current understanding of the role of 5-HT systems in alcohol dependence is incomplete, there is some evidence to suggest that 5-HT3 receptor antagonists are effective in people with the L/L genotype of the 5-HTTLPR polymorphism while SSRIs may be more beneficial to people with the S/L or S/S genotype. Studies that assess the impact of serotonin transporter polymorphisms on 5-HT circuit function and the subsequent development of alcohol use disorders will be an important step forward in treating alcohol dependence. Copyright © 2016 by the Research Society on Alcoholism.

Systemic modulation of serotonergic synapses via reuptake blockade or 5HT1A receptor antagonism does not alter perithreshold taste sensitivity in rats.

Science.gov (United States)

Mathes, Clare M; Spector, Alan C

2014-09-01

Systemic blockade of serotonin (5HT) reuptake with paroxetine has been shown to increase sensitivity to sucrose and quinine in humans. Here, using a 2-response operant taste detection task, we measured the effect of paroxetine and the 5HT1A receptor antagonist WAY100635 on the ability of rats to discriminate sucrose, NaCl, and citric acid from water. After establishing individual psychometric functions, 5 concentrations of each taste stimulus were chosen to represent the dynamic portion of the concentration-response curve, and the performance of the rats to these stimuli was assessed after vehicle, paroxetine (7mg/kg intraperitoneally), and WAY100635 (0.3mg/kg subcutaneously; 1mg/kg intravenously) administration. Although, at times, overall performance across concentrations dropped, at most, 5% from vehicle to drug conditions, no differences relative to vehicle were seen on the parameters of the psychometric function (asymptote, slope, or EC50) after drug administration. In contrast to findings in humans, our results suggest that modulation of 5HT activity has little impact on sucrose detectability at perithreshold concentrations in rats, at least at the doses used in this task. In the rat model, the purported paracrine/neurocrine action of serotonin in the taste bud may work in a manner that does not impact overt taste detection behavior. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Effects of Serotonin in Immune Cells

OpenAIRE

Herr, Nadine; Bode, Christoph; Duerschmied, Daniel

2017-01-01

Serotonin [5-hydroxytryptamine (5-HT)] plays an important role in many organs as a peripheral hormone. Most of the body’s serotonin is circulating in the bloodstream, transported by blood platelets and is released upon activation. The functions of serotonin are mediated by members of the 7 known mammalian serotonin receptor subtype classes (15 known subtypes), the serotonin transporter (SERT), and by covalent binding of serotonin to different effector proteins. Almost all immune cells express...

Novel selective and potent 5-HT reuptake inhibitors with 5-HT1D antagonist activity: chemistry and pharmacological evaluation of a series of thienopyran derivatives.

Science.gov (United States)

Torrado, Alicia; Lamas, Carlos; Agejas, Javier; Jiménez, Alma; Diaz, Nuria; Gilmore, Jeremy; Boot, John; Findlay, Jeremy; Hayhurst, Lorna; Wallace, Louise; Broadmore, Richard; Tomlinson, Rosemarie

2004-10-15

A series of compounds combining the naphthylpiperazine and thienopyran scaffolds has been prepared and evaluated for 5-HT reuptake inhibition with 5-HT1D antagonist activity. The design of these compounds has been based on the 'overlapping type' strategy where two pharmacophores are linked in a single molecule. The resultant dual pharmacological profile has the potential to deliver a more efficient treatment for depression.

Inverse agonism at α2A adrenoceptors augments the hypophagic effect of sibutramine in rats

NARCIS (Netherlands)

Janhunen, Sanna K.; van der Zwaal, Esther M.; la Fleur, Susanne E.; Adan, Roger A. H.

2011-01-01

Because the use of monoamine reuptake inhibitors as weight-reducing agents is limited by adverse effects, novel antiobesity drugs are needed. We studied acute effects of the noradrenaline (NA) and serotonin (5-HT) reuptake inhibitor sibutramine (SIB), alone and after pretreatment with α1- and

The Serotonin Transporter Undergoes Constitutive Internalization and Is Primarily Sorted to Late Endosomes and Lysosomal Degradation*

Science.gov (United States)

Rahbek-Clemmensen, Troels; Bay, Tina; Eriksen, Jacob; Gether, Ulrik; Jørgensen, Trine Nygaard

2014-01-01

The serotonin transporter (SERT) plays a critical role in regulating serotonin signaling by mediating reuptake of serotonin from the extracellular space. The molecular and cellular mechanisms controlling SERT levels in the membrane remain poorly understood. To study trafficking of the surface resident SERT, two functional epitope-tagged variants were generated. Fusion of a FLAG-tagged one-transmembrane segment protein Tac to the SERT N terminus generated a transporter with an extracellular epitope suited for trafficking studies (TacSERT). Likewise, a construct with an extracellular antibody epitope was generated by introducing an HA (hemagglutinin) tag in the extracellular loop 2 of SERT (HA-SERT). By using TacSERT and HA-SERT in antibody-based internalization assays, we show that SERT undergoes constitutive internalization in a dynamin-dependent manner. Confocal images of constitutively internalized SERT demonstrated that SERT primarily co-localized with the late endosomal/lysosomal marker Rab7, whereas little co-localization was observed with the Rab11, a marker of the “long loop” recycling pathway. This sorting pattern was distinct from that of a prototypical recycling membrane protein, the β2-adrenergic receptor. Furthermore, internalized SERT co-localized with the lysosomal marker LysoTracker and not with transferrin. The sorting pattern was further confirmed by visualizing internalization of SERT using the fluorescent cocaine analog JHC1-64 and by reversible and pulse-chase biotinylation assays showing evidence for lysosomal degradation of the internalized transporter. Finally, we found that SERT internalized in response to stimulation with 12-myristate 13-acetate co-localized primarily with Rab7- and LysoTracker-positive compartments. We conclude that SERT is constitutively internalized and that the internalized transporter is sorted mainly to degradation. PMID:24973209

Sertraline-induced periorbital purpura: a case report.

Science.gov (United States)

Kayhan, Fatih; Eken, Zahide Eriş; Uguz, Faruk

2015-08-01

The incidence of mild to severe levels of spontaneous bleeding due to the usage of selective serotonin reuptake inhibitors (SSRIs) is relatively low. Although the exact mechanism is not known, it is thought that inhibition of the serotonin transporter together with a decrease in platelet serotonin could be responsible for the bleeding. Therefore, the use of SSRIs in conjunction with anti-aggregants may predispose to or exacerbate the risk of bleeding. In this case report, we describe a 44-year-old female patient with a diagnosis of anxiety disorder who spontaneously developed periorbital purpura during treatment with sertraline. Abnormal bleeding after treatment with an SSRI should be kept in mind, and alternative non-SSRI drugs of choice in such cases would be more appropriate. More extensive and comprehensive studies focusing on hemostasis and bleeding disorders are needed for SSRIs such as sertraline. © The Royal Australian and New Zealand College of Psychiatrists 2015.

Antidepressant use during pregnancy and the risk of major congenital malformations in a cohort of depressed pregnant women: an updated analysis of the Quebec Pregnancy Cohort.

Science.gov (United States)

Bérard, Anick; Zhao, Jin-Ping; Sheehy, Odile

2017-01-12

Antidepressant use during gestation has been associated with risk of major congenital malformations but estimates can lack statistical power or be confounded by maternal depression. We aimed to determine the association between first-trimester exposure to antidepressants and the risk of major congenital malformations in a cohort of depressed/anxious women. Data were obtained from the Quebec Pregnancy Cohort (QPC). All pregnancies with a diagnosis of depression or anxiety, or exposed to antidepressants in the 12 months before pregnancy, and ending with a live-born singleton were included. Antidepressant classes (selective serotonin reuptake inhibitors (SSRI), serotonin-norepinephrine reuptake inhibitors (SNRI), tricyclic antidepressants (TCA) and other antidepressants) and types were individually compared with non-exposure during the first trimester (depressed untreated). Major congenital malformations overall and organ-specific malformations in the first year of life were identified. 18 487 pregnant women were included. When looking at the specific types of antidepressant used during the first trimester, only citalopram was increasing the risk of major congenital malformations (adjusted OR, (aOR) 1.36, 95% CI 1.08 to 1.73; 88 exposed cases), although there was a trend towards increased risk for the most frequently used antidepressants. Antidepressants with serotonin reuptake inhibition effect (SSRI, SNRI, amitriptyline (the most used TCA)) increased the risk of certain organ-specific defects: paroxetine increased the risk of cardiac defects (aOR 1.45, 95% CI 1.12 to 1.88), and ventricular/atrial septal defects (aOR 1.39, 95% CI 1.00 to 1.93); citalopram increased the risk of musculoskeletal defects (aOR 1.92, 95% CI 1.40 to 2.62), and craniosynostosis (aOR 3.95, 95% CI 2.08 to 7.52); TCA was associated with eye, ear, face and neck defects (aOR 2.45, 95% CI 1.05 to 5.72), and digestive defects (aOR 2.55, 95% CI 1.40 to 4.66); and venlafaxine was associated with

An approach for serotonin depletion in pigs: effects on serotonin receptor binding

DEFF Research Database (Denmark)

Ettrup, Anders; Kornum, Birgitte R; Weikop, Pia

2011-01-01

Depletion of central serotonin (5-HT) levels and dysfunction in serotonergic transmission are implicated in a variety of human CNS disorders. The mechanisms behind these serotonergic deficits have been widely studied using rodent models, but only to a limited extent in larger animal models. The pig...... is increasingly used as an experimental animal model especially in neuroscience research. Here, we present an approach for serotonin depletion in the pig brain. Central serotonin depletion in Danish Landrace pigs was achieved following 4 days treatment with para-chlorophenylalanine (pCPA). On day 5, tissue...... average decreases in 5-HT concentrations of 61% ± 14% and 66% ± 16%, respectively, and a substantial loss of 5-HT immunostaining was seen throughout the brain. The serotonin depletion significantly increased 5-HT₄ receptor binding in nucleus accumbens, but did not alter 5-HT(1A) and 5-HT(2A) receptor...

An approach for serotonin depletion in pigs: effects on serotonin receptor binding

DEFF Research Database (Denmark)

Ettrup, Anders; Kornum, Birgitte R; Weikop, Pia

2011-01-01

Depletion of central serotonin (5-HT) levels and dysfunction in serotonergic transmission are implicated in a variety of human CNS disorders. The mechanisms behind these serotonergic deficits have been widely studied using rodent models, but only to a limited extent in larger animal models. The pig...... is increasingly used as an experimental animal model especially in neuroscience research. Here, we present an approach for serotonin depletion in the pig brain. Central serotonin depletion in Danish Landrace pigs was achieved following 4 days treatment with para-chlorophenylalanine (pCPA). On day 5, tissue...... average decreases in 5-HT concentrations of 61% ± 14% and 66% ± 16%, respectively, and a substantial loss of 5-HT immunostaining was seen throughout the brain. The serotonin depletion significantly increased 5-HT4 receptor binding in nucleus accumbens, but did not alter 5-HT(1A) and 5-HT(2A) receptor...

Serotonin metabolism in rat brain

International Nuclear Information System (INIS)

Schutte, H.H.

1976-01-01

The metabolism of serotonin in rat brain was studied by measuring specific activities of tryptophan in plasma and of serotonin, 5-hydroxyindole acetic acid and tryptophan in the brain after intravenous injection of tritiated tryptophan. For a detailed analysis of the specific activities, a computer simulation technique was used. It was found that only a minor part of serotonin in rat brain is synthesized from tryptophan rapidly transported from the blood. It is suggested that the brain tryptophan originates from brain proteins. It was also found that the serotonin in rat brain is divided into more than one metabolic compartment

Síndrome de Gilles de la Tourette associada ao transtorno de déficit de atenção com hiperatividade: resposta clínica satisfatória a inibidor seletivo da recaptura de serotonina e metilfenidato Tourette syndrome associated with attention-deficit hyperactivity disorder: satisfactory clinical response to selective serotonin reuptake inhibitor and methylphenidate

Directory of Open Access Journals (Sweden)

Roberta Benitez Freitas Passos

2010-01-01

Full Text Available A Síndrome de Gilles de la Tourette (SGT, caracterizada pela presença de tiques motores e vocais, apresenta elevada associação com transtorno obsessivo-compulsivo (TOC e transtorno de déficit de atenção com hiperatividade (TDAH. Essas condições frequentemente causam mais prejuízo aos pacientes do que os tiques, propriamente. Relata-se o caso clínico de um paciente com SGT e comorbidade com TDAH e TOC. O tratamento com inibidor seletivo de recaptura de serotonina (ISRS e metilfenidato promoveu melhora significativa dos sintomas de TDAH, sintomas compulsivos e tiques.Tourette Syndrome (TS, characterized by motor and vocal tics, is often associated with obsessive compulsive disorder (OCD and attention-deficit hyperactivity disorder (ADHD. These associated conditions frequently cause more impairment in patients than tics themselves. We report the case of TS with comorbid ADHD and OCD. Treatment with selective serotonin reuptake inhibitor and methylphenidate, led to significantly improvement of ADHD symptoms, compulsive symptoms and tics.

Serotonin Receptors in Hippocampus

Science.gov (United States)

Berumen, Laura Cristina; Rodríguez, Angelina; Miledi, Ricardo; García-Alcocer, Guadalupe

2012-01-01

Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a functional network that uses several serotonin receptors to regulate their roles in this particular part of the limbic system. PMID:22629209

Radioprotective action of serotonin

Energy Technology Data Exchange (ETDEWEB)

Vodop' yanova, L G; Vinogradova, M F [Leningradskij Gosudarstvennyj Univ. (USSR). Biologicheskij Nauchno-Issledovatel' skij Inst.

1975-09-01

Tests in vitro were performed to study the effect of serotonin on oxidative phosphorylation in the mitochondria of rat liver. Serotonin (2.10/sup -4/ M) was shown to suppress oxidation of ..cap alpha..-ketoglutaric acid without significantly changing succinic acid consumption. A comparison of the results obtained with those from the literature allowed to assume that the radioprotective effect of serotonin was based not only on its previously known ability to cause tissue hypoxia, but also on its ability to affect oxidation processes in mitochondria.

Waterborne citalopram has anxiolytic effects and increases locomotor activity in the three-spine stickleback (Gasterosteus aculeatus)

DEFF Research Database (Denmark)

Kellner, M; Porseryd, T; Hallgren, S

2016-01-01

Citalopram is an antidepressant drug, which acts by inhibiting the re-uptake of serotonin from the synaptic cleft into the pre-synaptic nerve ending. It is one of the most common drugs used in treatment of depression, it is highly lipophilic and frequently found in sewage treatment plant effluents...... object and aggressive behaviour was investigated using the Novel Object test and a mirror test, respectively. The exposed fish ventured close to the unknown object significantly more often and stayed there for significantly longer time than unexposed fish. The aggression test yielded no statistically...

Venlafaxine and Oxycodone Effects on Human Spinal and Supraspinal Pain Processing

DEFF Research Database (Denmark)

Lelic, D; Fischer, I W D; Olesen, Anne Estrup

2016-01-01

affect spinal and supraspinal pain processing. Twenty volunteers were included in this randomized cross-over study comparing 5-day treatment with venlafaxine, oxycodone and placebo. As a proxy of the spinal pain transmission, the nociceptive withdrawal reflex (NWR) to electrical stimulation on the sole......Severe pain is often treated with opioids. Antidepressants that inhibit serotonin and norepinephrine reuptake (SNRI) have also shown a pain relieving effect, but for both SNRI and opioids, the specific mode of action in humans remains vague. This study investigated how oxycodone and venlafaxine...

Transient thyrotoxicosis from thyroiditis induced by sibutramine overdose: a case report.

Science.gov (United States)

Kim, S K; Lee, S M; Yoo, S S; Hahm, J R; Jung, J H; Kim, H S; Kim, S; Chung, S I; Jung, T S

2013-08-01

Sibutramine is an antiobesity drug that inhibits the reuptake of serotonin and noradrenalin in the hypothalamus. A 37-year-old Korean man presented to the emergency room for the oral intake of 280 mg of sibutramine. The patient was in thyrotoxic state. The (99m)Technetium-pertechnetate thyroid scan showed irregular uptake of radioisotope and thyroid-stimulating hormone receptor antibody and thyroperoxidase antibody were negative. Thyroid function normalized after that. The patient had transient thyrotoxicosis with thyroiditis. We report a case of thyrotoxicosis accompanied by thyroiditis resulting from the intentional overdose of sibutramine.

Chronic Enhancement of Serotonin Facilitates Excitatory Transcranial Direct Current Stimulation-Induced Neuroplasticity.

Science.gov (United States)

Kuo, Hsiao-I; Paulus, Walter; Batsikadze, Giorgi; Jamil, Asif; Kuo, Min-Fang; Nitsche, Michael A

2016-04-01

Serotonin affects memory formation via modulating long-term potentiation (LTP) and depression (LTD). Accordingly, acute selective serotonin reuptake inhibitor (SSRI) administration enhanced LTP-like plasticity induced by transcranial direct current stimulation (tDCS) in humans. However, it usually takes some time for SSRI to reduce clinical symptoms such as anxiety, negative mood, and related symptoms of depression and anxiety disorders. This might be related to an at least partially different effect of chronic serotonergic enhancement on plasticity, as compared with single-dose medication. Here we explored the impact of chronic application of the SSRI citalopram (CIT) on plasticity induced by tDCS in healthy humans in a partially double-blinded, placebo (PLC)-controlled, randomized crossover study. Furthermore, we explored the dependency of plasticity induction from the glutamatergic system via N-methyl-D-aspartate receptor antagonism. Twelve healthy subjects received PLC medication, combined with anodal or cathodal tDCS of the primary motor cortex. Afterwards, the same subjects took CIT (20 mg/day) consecutively for 35 days. During this period, four additional interventions were performed (CIT and PLC medication with anodal/cathodal tDCS, CIT and dextromethorphan (150 mg) with anodal/cathodal tDCS). Plasticity was monitored by motor-evoked potential amplitudes elicited by transcranial magnetic stimulation. Chronic application of CIT increased and prolonged the LTP-like plasticity induced by anodal tDCS for over 24 h, and converted cathodal tDCS-induced LTD-like plasticity into facilitation. These effects were abolished by dextromethorphan. Chronic serotonergic enhancement results in a strengthening of LTP-like glutamatergic plasticity, which might partially explain the therapeutic impact of SSRIs in depression and other neuropsychiatric diseases.

Fluoxetine Exerts Age-Dependent Effects on Behavior and Amygdala Neuroplasticity in the Rat

NARCIS (Netherlands)

Homberg, Judith R.; Olivier, Jocelien D. A.; Blom, Tom; Arentsen, Tim; van Brunschot, Chantal; Schipper, Pieter; Korte-Bouws, Gerdien; van Luijtelaar, Gilles; Reneman, Liesbeth

2011-01-01

The selective serotonin reuptake inhibitor (SSRI) Prozac (R) (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and

Fluoxetine exerts age-dependent effects on behavior and amygdala neuroplasticity in the rat.

NARCIS (Netherlands)

Homberg, J.R.; Olivier, J.D.A.; Blom, T.; Arentsen, T.; Brunschot, C. van; Schipper, P.; Korte-Bouws, G.A.; Luijtelaar, E.L.J.M. van; Reneman, L.

2011-01-01

The selective serotonin reuptake inhibitor (SSRI) Prozac(R) (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and

Fluoxetine Exerts Age-Dependent Effects on Behavior and Amygdala Neuroplasticity in the Rat

NARCIS (Netherlands)

Homberg, J.R.; Olivier, J.D.A.; Blom, T.; Arentsen, T.; Brunschot, C. van; Schipper, P.; Korte-Bouws, G.A.; Luijtelaar, E.L.J.M. van; Reneman, L.

2011-01-01

The selective serotonin reuptake inhibitor (SSRI) Prozac® (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and thereby

Expression analysis for inverted effects of serotonin transporter inactivation

International Nuclear Information System (INIS)

Ichikawa, Manabu; Okamura-Oho, Yuko; Shimokawa, Kazuro; Kondo, Shinji; Nakamura, Sakiko; Yokota, Hideo; Himeno, Ryutaro; Lesch, Klaus-Peter; Hayashizaki, Yoshihide

2008-01-01

Inactivation of serotonin transporter (HTT) by pharmacologically in the neonate or genetically increases risk for depression in adulthood, whereas pharmacological inhibition of HTT ameliorates symptoms in depressed patients. The differing role of HTT function during early development and in adult brain plasticity in causing or reversing depression remains an unexplained paradox. To address this we profiled the gene expression of adult Htt knockout (Htt KO) mice and HTT inhibitor-treated mice. Inverted profile changes between the two experimental conditions were seen in 30 genes. Consistent results of the upstream regulatory element search and the co-localization search of these genes indicated that the regulation may be executed by Pax5, Pax7 and Gata3, known to be involved in the survival, proliferation, and migration of serotonergic neurons in the developing brain, and these factors are supposed to keep functioning to regulate downstream genes related to serotonin system in the adult brain

Effects of Methylphenidate and Atomoxetine on Cortical Inhibition in ADHD

Directory of Open Access Journals (Sweden)

J Gordon Millichap

2006-09-01

Full Text Available The effects of methylphenidate (MPH, a psychostimulant, and atomoxetine (ATX, a selective norepinephrine reuptake inhibitor, on short interval-cortical inhibition (SICI were measured in motor cortex with transcranial magnetic stimulation, in a study at Cincinnati Children’s Medical Center, OH, and other centers.

Suppressions of Serotonin-Induced Increased Vascular Permeability and Leukocyte Infiltration by Bixa orellana Leaf Extract

Directory of Open Access Journals (Sweden)

Yoke Keong Yong

2013-01-01

Full Text Available The aim of the present study was to evaluate the anti-inflammatory activities of aqueous extract of Bixa orellana (AEBO leaves and its possible mechanisms in animal models. The anti-inflammatory activity of the extract was evaluated using serotonin-induced rat paw edema, increased peritoneal vascular permeability, and leukocyte infiltrations in an air-pouch model. Nitric oxide (NO, indicated by the sum of nitrites and nitrates, and vascular growth endothelial growth factor (VEGF were measured in paw tissues of rats to determine their involvement in the regulation of increased permeability. Pretreatments with AEBO (50 and 150 mg kg−1 prior to serotonin inductions resulted in maximum inhibitions of 56.2% of paw volume, 45.7% of Evans blue dye leakage in the peritoneal vascular permeability model, and 83.9% of leukocyte infiltration in the air-pouch model. 57.2% maximum inhibition of NO and 27% of VEGF formations in rats’ paws were observed with AEBO at the dose of 150 mg kg−1. Pharmacological screening of the extract showed significant (P<0.05 anti-inflammatory activity, indicated by the suppressions of increased vascular permeability and leukocyte infiltration. The inhibitions of these inflammatory events are probably mediated via inhibition of NO and VEGF formation and release.

Fetzima (levomilnacipran), a drug for major depressive disorder as a dual inhibitor for human serotonin transporters and beta-site amyloid precursor protein cleaving enzyme-1.

Science.gov (United States)

Rizvi, Syed Mohd Danish; Shaikh, Sibhghatulla; Khan, Mahiuddin; Biswas, Deboshree; Hameed, Nida; Shakil, Shazi

2014-01-01

Pharmacological management of Major Depressive Disorder includes the use of serotonin reuptake inhibitors which targets serotonin transporters (SERT) to increase the synaptic concentrations of serotonin. Beta-site amyloid precursor protein cleaving enzyme-1 (BACE-1) is responsible for amyloid β plaque formation. Hence it is an interesting target for Alzheimer's disease (AD) therapy. This study describes molecular interactions of a new Food and Drug Administration approved antidepressant drug named 'Fetzima' with BACE-1 and SERT. Fetzima is chemically known as levomilnacipran. The study has explored a possible link between the treatment of Depression and AD. 'Autodock 4.2' was used for docking study. The free energy of binding (ΔG) values for 'levomilnacipran-SERT' interaction and 'levomilnacipran-BACE1' interaction were found to be -7.47 and -8.25 kcal/mol, respectively. Levomilnacipran was found to interact with S438, known to be the most important amino acid residue of serotonin binding site of SERT during 'levomilnacipran-SERT' interaction. In the case of 'levomilnacipran-BACE1' interaction, levomilnacipran interacted with two very crucial aspartic acid residues of BACE-1, namely, D32 and D228. These residues are accountable for the cleavage of amyloid precursor protein and the subsequent formation of amyloid β plaques in AD brain. Hence, Fetzima (levomilnacipran) might act as a potent dual inhibitor of SERT and BACE-1 and expected to form the basis of a future dual therapy against depression and AD. It is an established fact that development of AD is associated with Major Depressive Disorder. Therefore, the design of new BACE-1 inhibitors based on antidepressant drug scaffolds would be particularly beneficial.

Rotavirus and Serotonin Cross-Talk in Diarrhoea

Science.gov (United States)

Nordgren, Johan; Karlsson, Thommie; Sharma, Sumit; Magnusson, Karl-Eric; Svensson, Lennart

2016-01-01

Rotavirus (RV) has been shown to infect and stimulate secretion of serotonin from human enterochromaffin (EC) cells and to infect EC cells in the small intestine of mice. It remains to identify which intracellularly expressed viral protein(s) is responsible for this novel property and to further establish the clinical role of serotonin in RV infection. First, we found that siRNA specifically silencing NSP4 (siRNANSP4) significantly attenuated secretion of serotonin from Rhesus rotavirus (RRV) infected EC tumor cells compared to siRNAVP4, siRNAVP6 and siRNAVP7. Second, intracellular calcium mobilization and diarrhoeal capacity from virulent and avirulent porcine viruses correlated with the capacity to release serotonin from EC tumor cells. Third, following administration of serotonin, all (10/10) infants, but no (0/8) adult mice, responded with diarrhoea. Finally, blocking of serotonin receptors using Ondansetron significantly attenuated murine RV (strain EDIM) diarrhoea in infant mice (2.9 vs 4.5 days). Ondansetron-treated mice (n = 11) had significantly (p serotonin receptor antagonist significantly (p serotonin from human EC tumor cells and that serotonin participates in RV diarrhoea, which can be attenuated by Ondansetron. PMID:27459372

Influence of serotonin and melatonin on some parameters of gastrointestinal activity.

Science.gov (United States)

Bubenik, G A; Dhanvantari, S

1989-01-01

In vitro melatonin (M) reduced the tone of gut muscles and counteracted the tonic effect of serotonin (5-HT). In vivo 0.1 to 4 mg of 5-HT (contained in beeswax implants) decreased the food transit time (FTT) in a dose-dependent manner, but higher doses (5 and 6 mg) increased the FTT. Melatonin injected intraperitoneally into mice bearing 5-HT implants (2 mg per animal) blocked partly the serotonin effect and increased FTT by 50%; however, no dose-dependent effect was observed when doses between 0.01 and 1 mg were used. Surprisingly, M injected into intact mice decreased FTT to levels comparable to those observed in 5-HT implanted, M-treated mice. Again, this significant decrease was not dose-dependent between 0.02 and 1 mg. Although in vitro the maximal inhibition of serotonin-induced spasm was achieved when the M:5-HT ratio was 50-100:1, in vivo the effective ratio was about 1:1. This may indicate that part of M action on the gut movement is mediated by extraintestinal mechanisms. A hypothetical, counterbalancing system of M and 5-HT regulation of gut activity (similar to adrenaline-acetylcholine system) is proposed.

Characterization of an allosteric citalopram-binding site at the serotonin transporter

DEFF Research Database (Denmark)

Chen, Fenghua; Breum Larsen, Mads; Neubauer, Henrik Amtoft

2005-01-01

The serotonin transporter (SERT), which belongs to a family of       sodium/chloride-dependent transporters, is the major pharmacological       target in the treatment of several clinical disorders, including       depression and anxiety. In the present study we show that the dissociation......       rate, of [3H]S-citalopram from human SERT, is retarded by the presence of       serotonin, as well as by several antidepressants, when present in the       dissociation buffer. Dissociation of [3H]S-citalopram from SERT is most       potently inhibited by S-citalopram followed by R......-citalopram, sertraline,       serotonin and paroxetine. EC50 values for S- and R-citalopram are 3.6 +/-       0.4 microm and 19.4 +/- 2.3 microm, respectively. Fluoxetine, venlafaxine       and duloxetine have no significant effect on the dissociation of       [3H]S-citalopram. Allosteric modulation of dissociation...

Serotonin neurones have anti-convulsant effects and reduce seizure-induced mortality

Science.gov (United States)

Buchanan, Gordon F; Murray, Nicholas M; Hajek, Michael A; Richerson, George B

2014-01-01

Sudden unexpected death in epilepsy (SUDEP) is the leading cause of death in patients with refractory epilepsy. Defects in central control of breathing are important contributors to the pathophysiology of SUDEP, and serotonin (5-HT) system dysfunction may be involved. Here we examined the effect of 5-HT neurone elimination or 5-HT reduction on seizure risk and seizure-induced mortality. Adult Lmx1bf/f/p mice, which lack >99% of 5-HT neurones in the CNS, and littermate controls (Lmx1bf/f) were subjected to acute seizure induction by maximal electroshock (MES) or pilocarpine, variably including electroencephalography, electrocardiography, plethysmography, mechanical ventilation or pharmacological therapy. Lmx1bf/f/p mice had a lower seizure threshold and increased seizure-induced mortality. Breathing ceased during most seizures without recovery, whereas cardiac activity persisted for up to 9 min before terminal arrest. The mortality rate of mice of both genotypes was reduced by mechanical ventilation during the seizure or 5-HT2A receptor agonist pretreatment. The selective serotonin reuptake inhibitor citalopram reduced mortality of Lmx1bf/f but not of Lmx1bf/f/p mice. In C57BL/6N mice, reduction of 5-HT synthesis with para-chlorophenylalanine increased MES-induced seizure severity but not mortality. We conclude that 5-HT neurones raise seizure threshold and decrease seizure-related mortality. Death ensued from respiratory failure, followed by terminal asystole. Given that SUDEP often occurs in association with generalised seizures, some mechanisms causing death in our model might be shared with those leading to SUDEP. This model may help determine the relationship between seizures, 5-HT system dysfunction, breathing and death, which may lead to novel ways to prevent SUDEP. PMID:25107926

Brain serotonin content regulates the manifestation of tramadol-induced seizures in rats: disparity between tramadol-induced seizure and serotonin syndrome.

Science.gov (United States)

Fujimoto, Yohei; Funao, Tomoharu; Suehiro, Koichi; Takahashi, Ryota; Mori, Takashi; Nishikawa, Kiyonobu

2015-01-01

Tramadol-induced seizures might be pathologically associated with serotonin syndrome. Here, the authors investigated the relationship between serotonin and the seizure-inducing potential of tramadol. Two groups of rats received pretreatment to modulate brain levels of serotonin and one group was treated as a sham control (n = 6 per group). Serotonin modulation groups received either para-chlorophenylalanine or benserazide + 5-hydroxytryptophan. Serotonin, dopamine, and histamine levels in the posterior hypothalamus were then measured by microdialysis, while simultaneously infusing tramadol until seizure onset. In another experiment, seizure threshold with tramadol was investigated in rats intracerebroventricularly administered with either a serotonin receptor antagonist (methysergide) or saline (n = 6). Pretreatment significantly affected seizure threshold and serotonin fluctuations. The threshold was lowered in para-chlorophenylalanine group and raised in benserazide + 5-hydroxytryptophan group (The mean ± SEM amount of tramadol needed to induce seizures; sham: 43.1 ± 4.2 mg/kg, para-chlorophenylalanine: 23.2 ± 2.8 mg/kg, benserazide + 5-hydroxytryptophan: 59.4 ± 16.5 mg/kg). Levels of serotonin at baseline, and their augmentation with tramadol infusion, were less in the para-chlorophenylalanine group and greater in the benserazide + 5-hydroxytryptophan group. Furthermore, seizure thresholds were negatively correlated with serotonin levels (correlation coefficient; 0.71, P seizure threshold (P seizures, and that serotonin concentrations were negatively associated with seizure thresholds. Moreover, serotonin receptor antagonism precipitated seizure manifestation, indicating that tramadol-induced seizures are distinct from serotonin syndrome.

Depression in general practice

African Journals Online (AJOL)

Most persons with emotional disorders are evaluated and treated by primary health ... the full clinical picture has emerged, and in most of their patients the .... Depression is common in attention deficit disorder where hyperactivity ... tncyclic antidepressants, SSRls ; selective serotonin re-uptake inhibitors; SNRls ; serotonin ...

Fluoxetine augments ventilatory CO2 sensitivity in Brown Norway but not Sprague Dawley rats.

Science.gov (United States)

Hodges, Matthew R; Echert, Ashley E; Puissant, Madeleine M; Mouradian, Gary C

2013-04-01

The Brown Norway (BN; BN/NHsdMcwi) rat exhibits a deficit in ventilatory CO2 sensitivity and a modest serotonin (5-HT) deficiency. Here, we tested the hypothesis that the selective serotonin reuptake inhibitor fluoxetine would augment CO2 sensitivity in BN but not Sprague Dawley (SD) rats. Ventilation during room air or 7% CO2 exposure was measured before, during and after 3 weeks of daily injections of saline or fluoxetine (10mg/(kgday)) in adult male BN and SD rats. Fluoxetine had minimal effects on room air breathing in BN and SD rats (p>0.05), although tidal volume (VT) was reduced in BN rats (peffects of fluoxetine on CO2 sensitivity in SD rats, but fluoxetine increased minute ventilation, breathing frequency and VT during hypercapnia in BN rats (pCO2 response was reversible upon withdrawal of fluoxetine. Brain levels of biogenic amines were largely unaffected, but 5-HIAA and the ratio of 5-HIAA/5-HT were reduced (peffective 5-HT reuptake inhibition. Thus, fluoxetine increases ventilatory CO2 sensitivity in BN but not SD rats, further suggesting altered 5-HT system function may contribute to the inherently low CO2 sensitivity in the BN rat. Copyright © 2013 Elsevier B.V. All rights reserved.

Modulation of Tryptophan and Serotonin Metabolism as a Biochemical Basis of the Behavioral Effects of Use and Withdrawal of Androgenic-Anabolic Steroids and Other Image- and Performance-Enhancing Agents

Directory of Open Access Journals (Sweden)

Abdulla A-B Badawy

2018-02-01

Full Text Available Modulation of tryptophan (Trp metabolism may underpin the behavioral effects of androgenic-anabolic steroids (AAS and associated image and performance enhancers. Euphoria, arousal, and decreased anxiety observed with moderate use and exercise may involve enhanced cerebral serotonin synthesis and function by increased release of albumin-bound Trp and estrogen-mediated liver Trp 2,3-dioxygenase (TDO inhibition and enhancement of serotonin function. Aggression, anxiety, depression, personality disorders, and psychosis, observed on withdrawal of AAS or with use of large doses, can be caused by decreased serotonin synthesis due to TDO induction on withdrawal, excess Trp inhibiting the 2 enzymes of serotonin synthesis, and increased cerebral levels of neuroactive kynurenines. Exercise and excessive protein and branched-chain amino acid intakes may aggravate the effects of large AAS dosage. The hypothesis is testable in humans and experimental animals by measuring parameters of Trp metabolism and disposition and related metabolic processes.

Psychopharmacological strategies in the management of posttraumatic stress disorder (PTSD): what have we learned?

Science.gov (United States)

Bernardy, Nancy C; Friedman, Matthew J

2015-04-01

There have been significant advancements in the pharmacologic management of posttraumatic stress disorder (PTSD) in the past two decades. Multisite randomized clinical trials (RCTs) have noted the efficacy of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNR Is) for PTSD treatment. Unfortunately, there have been no new medications approved to treat PTSD in the past 10 years. Although there have been exciting new findings in our knowledge of the neurobiology of PTSD, clinical trials testing new medications have lagged. This review summarizes recent research that builds on the unique pathophysiology of PTSD and suggests ways to move the field forward.

Diffuse noxious inhibitory controls and nerve injury: restoring an imbalance between descending monoamine inhibitions and facilitations.

Science.gov (United States)

Bannister, Kirsty; Patel, Ryan; Goncalves, Leonor; Townson, Louisa; Dickenson, Anthony H

2015-09-01

Diffuse noxious inhibitory controls (DNICs) utilize descending inhibitory controls through poorly understood brain stem pathways. The human counterpart, conditioned pain modulation, is reduced in patients with neuropathy aligned with animal data showing a loss of descending inhibitory noradrenaline controls together with a gain of 5-HT3 receptor-mediated facilitations after neuropathy. We investigated the pharmacological basis of DNIC and whether it can be restored after neuropathy. Deep dorsal horn neurons were activated by von Frey filaments applied to the hind paw, and DNIC was induced by a pinch applied to the ear in isoflurane-anaesthetized animals. Spinal nerve ligation was the model of neuropathy. Diffuse noxious inhibitory control was present in control rats but abolished after neuropathy. α2 adrenoceptor mechanisms underlie DNIC because the antagonists, yohimbine and atipamezole, markedly attenuated this descending inhibition. We restored DNIC in spinal nerve ligated animals by blocking 5-HT3 descending facilitations with the antagonist ondansetron or by enhancing norepinephrine modulation through the use of reboxetine (a norepinephrine reuptake inhibitor, NRI) or tapentadol (μ-opioid receptor agonist and NRI). Additionally, ondansetron enhanced DNIC in normal animals. Diffuse noxious inhibitory controls are reduced after peripheral nerve injury illustrating the central impact of neuropathy, leading to an imbalance in descending excitations and inhibitions. Underlying noradrenergic mechanisms explain the relationship between conditioned pain modulation and the use of tapentadol and duloxetine (a serotonin, NRI) in patients. We suggest that pharmacological strategies through manipulation of the monoamine system could be used to enhance DNIC in patients by blocking descending facilitations with ondansetron or enhancing norepinephrine inhibitions, so possibly reducing chronic pain.

GENetic and clinical Predictors Of treatment response in Depression: the GenPod randomised trial protocol

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O'Donovan Michael

2008-05-01

Full Text Available Abstract Background The most effective pharmacological treatments for depression inhibit the transporters that reuptake serotonin (Selective Serotonin Reuptake Inhibitors – SSRIs and noradrenaline (Noradrenaline Reuptake Inhibitors – NaRIs into the presynaptic terminal. There is evidence to suggest that noradrenaline and serotonin enhancing drugs work through separate mechanisms to produce their clinical antidepressant action. Although most of the current evidence suggests there is little difference in overall efficacy between SSRIs and NaRIs, there are patients who respond to one class of compounds and not another. This suggests that treatment response could be predicted by genetic and/or clinical characteristics. Firstly, this study aims to investigate the influence of a polymorphism (SLC6A4 in the 5HT transporter in altering response to SSRI medication. Secondly, the study will investigate whether those with more severe depression have a better response to NaRIs than SSRIs. Methods/design The GenPod trial is a multi-centre randomised controlled trial. GPs referred patients aged between 18–74 years presenting with a new episode of depression, who did not have any medical contraindications to antidepressant medication and who had no history of psychosis or alcohol/substance abuse. Patients were interviewed to ascertain their suitability for the study. Eligible participants (with a primary diagnosis of depression according to ICD10 criteria and a Beck Depression Inventory (BDI score > 14 were randomised to receive one of two antidepressant treatments, either the SSRI Citalopram or the NaRI Reboxetine, stratified according to severity. The final number randomised to the trial was 601. Follow-up assessments took place at 2, 6 and 12 weeks following randomisation. Primary outcome was measured at 6 weeks by the BDI. Outcomes will be analysed on an intention-to-treat basis and will use multiple regression models to compare treatments

Glia and immune cell signaling in bipolar disorder: insights from neuropharmacology and molecular imaging to clinical application.

Science.gov (United States)

Watkins, C C; Sawa, A; Pomper, M G

2014-01-21

Bipolar disorder (BD) is a debilitating mental illness characterized by severe fluctuations in mood, sleep, energy and executive functioning. Pharmacological studies of selective serotonin reuptake inhibitors and the monoamine system have helped us to clinically understand bipolar depression. Mood stabilizers such as lithium and valproic acid, the first-line treatments for bipolar mania and depression, inhibit glycogen synthase kinase-3 beta (GSK-3β) and regulate the Wnt pathway. Recent investigations suggest that microglia, the resident immune cells of the brain, provide a physiological link between the serotonin system and the GSK-3β/Wnt pathway through neuroinflammation. We review the pharmacological, translational and brain imaging studies that support a role for microglia in regulating neurotransmitter synthesis and immune cell activation. These investigations provide a model for microglia involvement in the pathophysiology and phenotype of BD that may translate into improved therapies.

Deletion of Munc18-1 in 5-HT Neurons Results in Rapid Degeneration of the 5-HT System and Early Postnatal Lethality

NARCIS (Netherlands)

Dudok, J.J.; Groffen, A.J.A.; Toonen, R.F.G.; Verhage, M.

2011-01-01

The serotonin (5-HT) system densely innervates many brain areas and is important for proper brain development. To specifically ablate the 5-HT system we generated mutant mice carrying a floxed Munc18-1 gene and Cre recombinase driven by the 5-HT-specific serotonin reuptake transporter (SERT)

Preparation and evaluation of serotonin labelled with 125I

International Nuclear Information System (INIS)

Sivaprasad, N.; Geetha, R.; Ghodke, A.S.; Karmalkar, C.P.; Pilkhwal, N.S.; Sarnaik, J.S.; Borkute, S.D.; Nadkarni, G.D.

1999-01-01

Radiolabelled serotonin is an important tool for studying serotonin receptors and estimating serotonin levels in plants and animals. In this paper we report the synthesis of serotonin - 125 I. Tyrosine Methyl Ester (TME) was first labelled with 125 I using chloramine-T method. 125 I-TME was then conjugated with serotonin using carbodimide. The labelled conjugate was purified using gel filtration. Yield and radiochemical purity were estimated using electrophoresis and ITLC in different solvent systems. The binding of the purified tracer to serotonin receptors and serotonin antibodies was studied. (author)

Expression of brain derived neurotrophic factor, activity-regulated cytoskeleton protein mRNA, and enhancement of adult hippocampal neurogenesis in rats after sub-chronic and chronic treatment with the triple monoamine re-uptake inhibitor tesofensine

DEFF Research Database (Denmark)

Larsen, Marianne Hald; Rosenbrock, Holger; Sams-Dodd, Frank

2007-01-01

The changes of gene expression resulting from long-term exposure to monoamine antidepressant drugs in experimental animals are key to understanding the mechanisms of action of this class of drugs in man. Many of these genes and their products are either relevant biomarkers or directly involved...... in structural changes that are perhaps necessary for the antidepressant effect. Tesofensine is a novel triple monoamine reuptake inhibitor that acts to increase noradrenaline, serotonin, and dopamine neurotransmission. This study was undertaken to examine the effect of sub-chronic (5 days) and chronic (14 days......) administration of Tesofensine on the expression of brain derived neurotrophic factor (BDNF) and activity-regulated cytoskeleton protein (Arc) in the rat hippocampus. Furthermore, hippocampi from the same animals were used to investigate the effect on cell proliferation by means of Ki-67- and Neuro...

Fractal analysis of striatal dopamine re-uptake sites

International Nuclear Information System (INIS)

Kuikka, J.T.; Bergstroem, K.A.; Tiihonen, J.; Raesaenen, P.; Karhu, J.

1997-01-01

Spatial variation in regional blood flow, metabolism and receptor density within the brain and in other organs is measurable even with a low spatial resolution technique such as emission tomography. It has been previously shown that the observed variance increases with increasing number of subregions in the organ/tissue studied. This resolution-dependent variance can be described by fractal analysis. We studied striatal dopamine re-uptake sites in 39 healthy volunteers with high-resolution single-photon emission tomography using iodine-123 labelled 2β-carbomethoxy-3β-(4-iodophenyl)tropane ([ 123 I]β-CIT). The mean fractal dimension was 1.15±0.07. The results indicate that regional striatal dopamine re-uptake sites involve considerable spatial heterogeneity which is higher than the uniform density (dimension=1.00) but much lower than complete randomness (dimension=1.50). There was a gender difference, with females having a higher heterogeneity in both the left and the right striatum. In addition, we found striatal asymmetry (left-to-right heterogeneity ratio of 1.19±0.15; P<0.001), suggesting functional hemispheric lateralization consistent with the control of motor behaviour and integrative functions. (orig.). With 5 figs., 1 tab

Fractal analysis of striatal dopamine re-uptake sites

Energy Technology Data Exchange (ETDEWEB)

Kuikka, J.T.; Bergstroem, K.A. [Department of Clinical Physiology, Kuopio University Hospital, Kuopio (Finland); Tiihonen, J.; Raesaenen, P. [Department of Forensic Psychiatry, University of Kuopio and Niuvanniemi Hospital, Kuopio (Finland); Karhu, J. [Department of Clinical Neurophysiology, Kuopio University Hospital, Kuopio (Finland)

1997-09-01

Spatial variation in regional blood flow, metabolism and receptor density within the brain and in other organs is measurable even with a low spatial resolution technique such as emission tomography. It has been previously shown that the observed variance increases with increasing number of subregions in the organ/tissue studied. This resolution-dependent variance can be described by fractal analysis. We studied striatal dopamine re-uptake sites in 39 healthy volunteers with high-resolution single-photon emission tomography using iodine-123 labelled 2{beta}-carbomethoxy-3{beta}-(4-iodophenyl)tropane ([{sup 123}I]{beta}-CIT). The mean fractal dimension was 1.15{+-}0.07. The results indicate that regional striatal dopamine re-uptake sites involve considerable spatial heterogeneity which is higher than the uniform density (dimension=1.00) but much lower than complete randomness (dimension=1.50). There was a gender difference, with females having a higher heterogeneity in both the left and the right striatum. In addition, we found striatal asymmetry (left-to-right heterogeneity ratio of 1.19{+-}0.15; P<0.001), suggesting functional hemispheric lateralization consistent with the control of motor behaviour and integrative functions. (orig.). With 5 figs., 1 tab.

Effects of selective serotonin reuptake inhibitors on three sex steroids in two versions of the aromatase enzyme inhibition assay and in the H295R cell assay

DEFF Research Database (Denmark)

Jacobsen, Naja Wessel; Hansen, Cecilie Hurup; Nellemann, Christine

2015-01-01

shown to inhibit the aromatase enzyme in both types of aromatase assays. The IC50 values ranged from 3 to 600μM. All five SSRIs, were further investigated in the H295R cell line. All compounds altered the steroid secretion from the cells, the lowest observed effect levels were 0.9μM and 3.1μ....... In this study we investigated whether the endocrine effect due to SSRI exposure could be detected in well adopted in vitro steroidogenesis assays, two versions of the aromatase enzyme inhibition assay and the H295R cell assay. The five drugs citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline, were......M for sertraline and fluvoxamine, respectively. In general the H295R cell assay was more sensitive to SSRI exposure than the two aromatase assays, up to 20 times more sensitive. This indicates that the H295R cell line is a better tool for screening endocrine disrupting effects. Our findings show that the endocrine...

Serotonin 6 receptor controls alzheimer?s disease and depression

OpenAIRE

Yun, Hyung-Mun; Park, Kyung-Ran; Kim, Eun-Cheol; Kim, Sanghyeon; Hong, Jin Tae

2015-01-01

Alzheimer?s disease (AD) and depression in late life are one of the most severe health problems in the world disorders. Serotonin 6 receptor (5-HT6R) has caused much interest for potential roles in AD and depression. However, a causative role of perturbed 5-HT6R function between two diseases was poorly defined. In the present study, we found that a 5-HT6R antagonist, SB271036 rescued memory impairment by attenuating the generation of A? via the inhibition of ?-secretase activity and the inact...

Optimal treatment of social phobia: systematic review and meta-analysis

Directory of Open Access Journals (Sweden)

Scott KM

2012-05-01

Full Text Available John Canton, Kate M Scott, Paul GlueDepartment of Psychological Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New ZealandAbstract: This article proposes a number of recommendations for the treatment of generalized social phobia, based on a systematic literature review and meta-analysis. An optimal treatment regimen would include a combination of medication and psychotherapy, along with an assertive clinical management program. For medications, selective serotonin reuptake inhibitors and dual serotonin-norepinephrine reuptake inhibitors are first-line choices based on their efficacy and tolerability profiles. The nonselective monoamine oxidase inhibitor, phenelzine, may be more potent than these two drug classes, but because of its food and drug interaction liabilities, its use should be restricted to patients not responding to selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors. There are other medication classes with demonstrated efficacy in social phobia (benzodiazepines, antipsychotics, alpha-2-delta ligands, but due to limited published clinical trial data and the potential for dependence and withdrawal issues with benzodiazepines, it is unclear how best to incorporate these drugs into treatment regimens. There are very few clinical trials on the use of combined medications. Cognitive behavior therapy appears to be more effective than other evidence-based psychological techniques, and its effects appear to be more enduring than those of pharmacotherapy. There is some evidence, albeit limited to certain drug classes, that the combination of medication and cognitive behavior therapy may be more effective than either strategy used alone. Generalized social phobia is a chronic disorder, and many patients will require long-term support and treatment.Keywords: social phobia, social anxiety disorder, psychotherapy, cognitive behavior therapy, antidepressant

No effect of C1473G polymorphism in the tryptophan hydroxylase 2 gene on the response of the brain serotonin system to chronic fluoxetine treatment in mice.

Science.gov (United States)

Bazhenova, Ekaterina Y; Sinyakova, Nadezhda A; Kulikova, Elizabeth A; Kazarinova, Irina A; Bazovkina, Daria V; Gainetdinov, Raul R; Kulikov, Alexander V

2017-07-13

Selective serotonin reuptake inhibitors (SSRIs) are antidepressants that block serotonin transporter (SERT) and increase serotonin (5-HT) level in the synaptic cleft. The interaction between SERT and the key enzyme of 5-HT synthesis in the brain, tryptophan hydroxylase 2 (TPH2), is essential to maintain the brain 5-HT level. The G allele of C1473G polymorphism in Tph2 gene decreases enzyme activity by half in mouse brain. Here we studied effect of C1473G polymorphism on the reaction of brain 5-HT system to chronic fluoxetine treatment (120mg/l in drinking water, for 3 weeks) in adult males of the congenic B6-1473C and B6-1473G mouse lines with high and low enzyme activity, respectively. The polymorphism did not affect the levels of 5-HT, its metabolite, 5-hydroxyindoleacetic acid (5-HIAA) and Tph2 gene mRNA in the brain. Fluoxetine significantly attenuated 5-HT levels in the cortex and striatum, 5-HIAA concentrations in the cortex, hippocampus, striatum and midbrain, and Tph2 gene expression in the midbrain. However, we did not observed any effect of the genotype x treatment interaction on these neurochemical characteristics. Therefore, C1473G polymorphism does not seem to play an essential role in the reaction of the brain 5-HT system to chronic fluoxetine treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Depression may be associated with hippocampal volume changes ...

African Journals Online (AJOL)

Adele

REVIEW. S Afr Psychiatry Rev 2004;7:5-9. South African Psychiatry Review - August 2004. 5 .... century, with electroconvulsive therapy (ECT) preceding the devel- opment of ... ern Selective Serotonin Reuptake Inhibitors (SSRIs), Serotonin-No- ... sants (NaSSAs) and others of an atypical nature.11 At the last count, eighteen ...

A Novel Role of Serotonin Receptor 2B Agonist as an Anti-Melanogenesis Agent

Directory of Open Access Journals (Sweden)

Eun Ju Oh

2016-04-01

Full Text Available BW723C86, a serotonin receptor 2B agonist, has been investigated as a potential therapeutic for various conditions such as anxiety, hyperphagia and hypertension. However, the functional role of BW723C86 against melanogenesis remains unclear. In this study, we investigate the effect of serotonin receptor 2B (5-HTR2B agonist on melanogenesis and elucidate the mechanism involved. BW723C86 reduced melanin synthesis and intracellular tyrosinase activity in melan-A cells and normal human melanocytes. The expression of melanogenesis-related proteins (tyrosinase, TRP-1 and TRP-2 and microphthalmia-associated transcription factor (MITF in melan-A cells decreased after BW723C86 treatment. The promoter activity of MITF was also reduced by BW723C86 treatment. The reduced level of MITF was associated with inhibition of protein kinase A (PKA and cAMP response element-binding protein (CREB activation by BW723C86 treatment. These results suggest that the serotonin agonist BW723C86 could be a potential therapeutic agent for skin hyperpigmentation disorders.

Serotonin shapes risky decision making in monkeys.

Science.gov (United States)

Long, Arwen B; Kuhn, Cynthia M; Platt, Michael L

2009-12-01

Some people love taking risks, while others avoid gambles at all costs. The neural mechanisms underlying individual variation in preference for risky or certain outcomes, however, remain poorly understood. Although behavioral pathologies associated with compulsive gambling, addiction and other psychiatric disorders implicate deficient serotonin signaling in pathological decision making, there is little experimental evidence demonstrating a link between serotonin and risky decision making, in part due to the lack of a good animal model. We used dietary rapid tryptophan depletion (RTD) to acutely lower brain serotonin in three macaques performing a simple gambling task for fluid rewards. To confirm the efficacy of RTD experiments, we measured total plasma tryptophan using high-performance liquid chromatography (HPLC) with electrochemical detection. Reducing brain serotonin synthesis decreased preference for the safe option in a gambling task. Moreover, lowering brain serotonin function significantly decreased the premium required for monkeys to switch their preference to the risky option, suggesting that diminished serotonin signaling enhances the relative subjective value of the risky option. These results implicate serotonin in risk-sensitive decision making and, further, suggest pharmacological therapies for treating pathological risk preferences in disorders such as problem gambling and addiction.

The therapeutic potential of escitalopram in the treatment of panic disorder

Directory of Open Access Journals (Sweden)

Mark H Townsend

2007-01-01

Full Text Available Mark H Townsend, Erich J ConradDepartment of Psychiatry, Louisiana State University Health Sciences Center New Orleans, New Orleans, Louisiana, USAAbstract: Panic disorder is a chronic and disabling condition that is often accompanied by other psychiatric and medical conditions. The serotonin reuptake inhibitors (SSRIs and serotoninnorepinephrine reuptake inhibitors (SNRIs have been used effectively with panic disorder (PD and conditions in which panic attacks frequently occur. Escitalopram is the most selective SSRI and a variety of evidence suggests it is of great value in the treatment of panic disorder. In this paper, we review the theoretical and practical implications of its use.Keywords: panic disorder, escitalopram, antidepressant, serotonin

Fluoxetine and its active metabolite norfluoxetine disrupt estrogen synthesis in a co-culture model of the feto-placental unit.

Science.gov (United States)

Hudon Thibeault, Andrée-Anne; Laurent, Laetitia; Vo Duy, Sung; Sauvé, Sébastien; Caron, Patrick; Guillemette, Chantal; Sanderson, J Thomas; Vaillancourt, Cathy

2017-02-15

The effects of fluoxetine, one of the most prescribed selective serotonin-reuptake inhibitors (SSRIs) during pregnancy, and its active metabolite norfluoxetine were studied on placental aromatase (CYP19) and feto-placental steroidogenesis. Fluoxetine did not alter estrogen secretion in co-culture of fetal-like adrenocortical (H295R) and trophoblast-like (BeWo) cells used as a model of the feto-placental unit, although it induced CYP19 activity, apparently mediated by the serotonin (5-HT) 2A receptor/PKC signaling pathway. Norfluoxetine decreased estrogen secretion in the feto-placental co-culture and competitively inhibited catalytic CYP19 activity in BeWo cells. Decreased serotonin transporter (SERT) activity in the co-culture was comparable to 17β-estradiol treatment of BeWo cells. This work shows that the complex interaction of fluoxetine and norfluoxetine with placental estrogen production, involves 5-HT-dependent and -independent mechanisms. Considering the crucial role of estrogens during pregnancy, our results raise concern about the impact of SSRI treatment on placental function and fetal health. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The external gate of the human and Drosophila serotonin transporters requires a basic/acidic amino acid pair for 3,4-methylenedioxymethamphetamine (MDMA) translocation and the induction of substrate efflux.

Science.gov (United States)

Sealover, Natalie R; Felts, Bruce; Kuntz, Charles P; Jarrard, Rachel E; Hockerman, Gregory H; Lamb, Patrick W; Barker, Eric L; Henry, L Keith

2016-11-15

The substituted amphetamine, 3,4-methylenedioxy-methamphetamine (MDMA, ecstasy), is a widely used drug of abuse that induces non-exocytotic release of serotonin, dopamine, and norepinephrine through their cognate transporters as well as blocking the reuptake of neurotransmitter by the same transporters. The resulting dramatic increase in volume transmission and signal duration of neurotransmitters leads to psychotropic, stimulant, and entactogenic effects. The mechanism by which amphetamines drive reverse transport of the monoamines remains largely enigmatic, however, promising outcomes for the therapeutic utility of MDMA for post-traumatic stress disorder and the long-time use of the dopaminergic and noradrenergic-directed amphetamines in treatment of attention-deficit hyperactivity disorder and narcolepsy increases the importance of understanding this phenomenon. Previously, we identified functional differences between the human and Drosophila melanogaster serotonin transporters (hSERT and dSERT, respectively) revealing that MDMA is an effective substrate for hSERT but not dSERT even though serotonin is a potent substrate for both transporters. Chimeric dSERT/hSERT transporters revealed that the molecular components necessary for recognition of MDMA as a substrate was linked to regions of the protein flanking transmembrane domains (TM) V through IX. Here, we performed species-scanning mutagenesis of hSERT, dSERT and C. elegans SERT (ceSERT) along with biochemical and electrophysiological analysis and identified a single amino acid in TM10 (Glu394, hSERT; Asn484, dSERT, Asp517, ceSERT) that is primarily responsible for the differences in MDMA recognition. Our findings reveal that an acidic residue is necessary at this position for MDMA recognition as a substrate and serotonin releaser. Copyright © 2016 Elsevier Inc. All rights reserved.

Implications of genetic research on the role of the serotonin in depression: emphasis on the serotonin type 1A receptor and the serotonin transporter.

Science.gov (United States)

Neumeister, Alexander; Young, Theresa; Stastny, Juergen

2004-08-01

Serotonin systems appear to play a key role in the pathophysiology of major depressive disorder. Consequently, ongoing research determines whether serotonin related genes account for the very robust differential behavioral and neural mechanisms that discriminate patients with depression from healthy controls. Serotonin type 1(A) receptors and the serotonin transporters are reduced in depression, and recent genetic research in animals and humans has implicated both in depression. Preclinical studies have utilized a variety of animal models that have been used to explain pathophysiological mechanisms in humans, although it is not clear at all whether these models constitute relevant models for depression in humans. However, data from preclinical studies can generate hypotheses that are tested in humans by combining genetic data with behavioral and physiological challenge paradigms and neuroimaging. These studies will enhance our understanding about combined influences from multiple interacting genes, as well as from environmental factors on brain circuits and their function, and about how these mechanisms may contribute to the pathophysiology of neuropsychiatric disorders.

Thermogenic effects of sibutramine and its metabolites

Science.gov (United States)

Connoley, Ian P; Liu, Yong-Ling; Frost, Ian; Reckless, Ian P; Heal, David J; Stock, Michael J

1999-01-01

The thermogenic activity of the serotonin and noradrenaline reuptake inhibitor sibutramine (BTS 54524; Reductil) was investigated by measuring oxygen consumption (VO2) in rats treated with sibutramine or its two pharmacologically-active metabolites. Sibutramine caused a dose-dependent rise in VO2, with a dose of 10 mg kg−1 of sibutramine or its metabolites producing increases of up to 30% that were sustained for at least 6 h, and accompanied by significant increases (0.5–1.0°C) in body temperature. Based on the accumulation in vivo of radiolabelled 2-deoxy-[3H]-glucose, sibutramine had little or no effect on glucose utilization in most tissues, but caused an 18 fold increase in brown adipose tissue (BAT). Combined high, non-selective doses (20 mg kg−1) of the β-adrenoceptor antagonists, atenolol and ICI 118551, inhibited completely the VO2 response to sibutramine, but the response was unaffected by low, β1-adrenoceptor-selective (atenolol) or β2-adrenoceptor-selective (ICI 118551) doses (1 mg kg−1). The ganglionic blocking agent, chlorisondamine (15 mg kg−1), inhibited completely the VO2 response to the metabolites of sibutramine, but had no effect on the thermogenic response to the β3-adrenoceptor-selective agonist BRL 35135. Similar thermogenic responses were produced by simultaneous injection of nisoxetine and fluoxetine at doses (30 mg kg−1) that had no effect on VO2 when injected individually. It is concluded that stimulation of thermogenesis by sibutramine requires central reuptake inhibition of both serotonin and noradrenaline, resulting in increased efferent sympathetic activation of BAT thermogenesis via β3-adrenoceptor, and that this contributes to the compound's activity as an anti-obesity agent. PMID:10217544