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Dose-Related Effects of a Neonatal 6-OHDA Lesion on SKF 38393- and M-Chlorophenylpiperazine-Induced Oral Activity Responses of RatsGong, Li, Kostrzewa, Richard M., Perry, Ken W., Fuller, Ray W. 17 December 1993 (has links)
Neonatal 6-hydroxydopamine (6-OHDA) treatment of rats is associated with concurrent supersensitization of dopamine (DA) D1 and serotonin 5-HT1C receptors, for agonist-induced oral activity. The present study was conducted to determine if graded reduction of striatal DA content and/or graded elevation of striatal 5-HT content by 6-OHDA would alter sensitivity of either receptor type, and thereby influence oral activity responses to DA and 5-HT agonists. At 3 days after birth, groups of rats were pretreated with desipramine (20 mg/kg i.p.), 1 h before administration of a range of doses of 6-OHDA HBr (15, 30, 60, 100, 150 and 200 μg, i.c.v., salt form; half in each lateral ventricle) or the vehicle, saline (0.85%)-ascorbic acid (0.1%). Between 2 and 4 months, a series of challenge doses of SKF 38393 HCl (0.30 to 3.0 mg/kg i.p.) and m-chlorophenylpiperazine 2HCl (0.30 to 6.0 mg/kg i.p.; m-CPP 2HCl) were administered to each group of rats and oral activity was observed. Oral activity was determined for 1 min every 10 min during a 60-min period, starting 10 min after injection of agonist or vehicle. SKF 38393 dose-response curves demonstrated enhanced oral activity responses in rats lesioned neonatally with 150 or 200 μg of 6-OHDA. m-CPP dose-response curves demonstrated enhanced oral activity responses in these 2 groups of rats, as well as those lesioned neonatally with 100 μg of 6-OHDA. Striatal DA content was reduced by > 97% in these 3 groups of rats. Striatal 5-HT content was elevated by > 80% in rats treated neonatally with 150- or 200-μg doses of 6-OHDA, and by 50% in rats treated neonatally with the 100-μg dose of 6-OHDA. Lower doses of 6-OHDA produced less of an effect on striatal DA and 5-HT content. Regression analysis determined that both SKF 38393- and m-CPP-induced oral activities were most closely correlated with the magnitude of change in striatal content of DA. These findings demonstrate that 5-HT agonist responses can be enhanced when DA agonist responses are not enhanced. Also, in neonatal 6-OHDA-lesioned rats the extent of DA depletion vs. the extent of 5-HT elevation seems to be a critical factor in the enhanced behavioral effects of DA and 5-HT agonists.
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Serotoninergics Attenuate Hyperlocomotor Activity in Rats. Potential New Therapeutic Strategy for HyperactivityBrus, Ryszard, Nowak, Przemyslaw, Szkilnik, Ryszard, Mikolajun, Urszula, Kostrzewa, Richard M. 01 December 2004 (has links)
Hyperactivity is thought to be associated with an alteration of dopamine (DA) neurochemistry in brain. This conventional view became solidified on the basis of observed hyperactivity in DA-lesioned animals and effectiveness of the dopaminomimetics such as amphetamine (AMP) in abating hyperactivity in humans and in animal models of hyperactivity. However, because AMPreleases serotonin (5-HT) as well as DA, we investigated the potential role of 5-HT in an animal model of hyperactivity. We found that a greater intensity of hyperactivity was produced in rats when both DA and 5-HT neurons were damaged at appropriate times in ontogeny. Therefore, previously we proposed this as an animal model of attention deficit hyperactivity disorder (ADHD) - induced by destruction of dopaminergic neurons with 6-hydroxydopamine (6-OHDA (neonatally) and serotoninergic neurons with 5,7-dihydroxytryptamine (5,7-DHT) (in adulthood). In this model effects similar to that of AMP(attenuation of hyperlocomotion) were produced by m-chlorophenylpiperazine (m-CPP) but not by 1-phenylbiguanide (1-PG), respective 5-HT2 and 5-HT3 agonists. The effect of m-CPP was shown to be replicated by desipramine, and was largely attenuated by the 5-HT2 antagonist mianserin. These findings implicate 5-HT neurochemistry as potentially important therapeutic targets for treating human hyperactivity and possibly childhood ADHD.
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Antidepressants and the Risk of Dental Caries in Children and Adolescents : A Systematic Literature ReviewStahre, Linda, Svensson, Johanna January 2023 (has links)
This thesis aims to review if there is an association between antidepressants and caries in children and adolescents. Previous established evidence exhibits that adults prescribed tricyclic antidepressants have an increased risk of caries. Simultaneously, a global trend of increased prescriptions of antidepressant medications is seen. In Sweden during 2018, 0–17-year old’s on antidepressant medication represented 1,6% percent of the total population. It is of utmost relevance to investigate the association between antidepressants and caries as the increasing population of medicating children may lead to an increased caries prevalence. A systematic literature review was performed in accordance with PRISMAs guidelines. The title-abstract and keywords searches were conducted in the following seven bibliographic databases: PubMed, EMBASE, CINAHL, Scopus, Web of Science, PsycINFO and MedLine. The search consisted of blocks based on “caries”, “children” and “antidepressants”. Unique articles were reviewed from title and abstract. Articles that met the criteria were reviewed in full text. The search generated 1829 unique articles, 1891 were excluded from the predefined criteria. 10 articles were reviewed in full text. None of the articles were eligible within the criteria of inclusion. The conclusion is that further research is needed in this area to assess the possible association between antidepressants and caries in children and adolescents. / Uppsatsen syftar till att sammanställa forskningsläget för sambandet mellan antidepressiv medicinering och karies hos barn och ungdomar. Tidigare evidens visar att vuxna som medicinerar med tricykliska antidepressiva har ökad kariesrisk. Samtidigt kan man globalt se en generell förskrivningsökning av antidepressiva. I Sverige under 2018, utgjorde användarna av antidepressiva i åldersgruppen 0–17 år 1,6% av totalpopulationen. Det är av högsta relevans att undersöka om det finns en potentiell association mellan antidepressiva och karies finns då den ökande populationen av medicinerande barn kan medföra ökad kariesprevalens. En systematisk litteraturöversikt genomfördes enligt PRISMAs riktlinjer. Titel- sammanfattnings och nyckelordssökningen utnyttjade följande sju elektroniska databaser: PubMed, EMBASE, CINAHL, Scopus, Web of Science, PsycINFO och MedLine. Sökningen utfördes i block utifrån “karies”, “barn” och “antidepressiva”. Unika artiklar granskades utifrån titel och abstrakt. Artiklar som uppfyllde förutbestämda kriterier för inklusion granskades i fulltext. Utifrån sökningen påträffades 1829 unika artiklar, varav 1819 exkluderades utifrån från titel och abstrakt. 10 artiklar granskades i fulltext och vi konstaterade att ingen artikel uppfyllde kriterierierna. Slutsatsen för studien är att fler studier och mer forskning behövs inom området. Detta för att kunna svara på om det finns ett samband mellan antidepressiva och karies hos barn.
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The neural correlates of perinatal OCD: An exploratory investigation into serotonin risk genes and cortical morphologyMattina, Gabriella January 2020 (has links)
Introduction: Obsessive-compulsive disorder (OCD) is a complex disorder that is associated with significantly impaired functioning. The current prevailing model of OCD implicates dysfunction of the serotonergic neurotransmitter system and fronto-striatal neural networks, but challenges in replicating findings within OCD samples are often attributed to clinical heterogeneity. OCD symptoms that develop or worsen within the perinatal period appears to reflect a distinct subtype of the disorder, but the genetic and neurobiological factors that contributes to its presentation in women is poorly understood. In this dissertation, we aimed to review the literature on the genetic architecture of OCD, identify potential gene candidates for perinatal OCD and analyze one serotonin system gene according to OCD and possible subtypes using meta-analytic techniques. Based on these findings, we then tested the association of serotonergic candidate gene polymorphisms with the presence of infant-related obsessive-compulsive symptoms (OCS). Lastly, we investigated the cortical morphological features associated with perinatal OCD and OCS symptom severity in postpartum mothers.
Results: From prior reports in the literature and our own meta-analytic investigation, polymorphic variants in genes coding for the serotonergic transporter and serotonin 2A receptor subtype (SLC6A4 and HTR2A, respectively) appear to be candidates for perinatal OCD due to their association in female samples. However, upon investigation in our perinatal sample (n=107), we found no evidence to support the association of the 5-HTTLPR polymorphism of SLC6A4 with perinatal-related OCS, but larger samples are needed to confirm this finding. Due to technical challenges, the HTR2A polymorphism remains to be tested. Our novel whole-brain explorations revealed distinct cortical morphology associated with symptom worsening across the perinatal period, irrespective of diagnosis. Cortical parameters were not able to differentiate mothers with and without OCD; however, OCD mothers displayed positive correlations between cortical surface area and symptom severity in widespread regions, including the frontal, parietal, temporal and occipital cortex.
Conclusions: Overall, this body of work aimed to fill the gap in the literature by exploring the possible genetic and cortical correlates of perinatal-related OCS and OCD. While 5-HTTLPR or HTR2A are candidates for perinatal OCD, it is not yet clear whether they increase susceptibility for the development of infant-related OCS in the perinatal period. Distinct cortical alterations in surface area appeared alongside OCS exacerbation in the postpartum period in regions that extend beyond the frontoparietal network. This suggests that additional neural networks may be contributing to symptom severity and that the cortical plasticity that occurs across the perinatal period may predispose women for risk of OCD. Future studies should continue to use a multiple perspective approach, that utilizes genetic and neurobiological techniques, in order to provide greater insight into the etiology of perinatal OCD. / Dissertation / Doctor of Philosophy (PhD) / Women are at greater risk for the development of mental illness in the time surrounding pregnancy and postpartum, known as the perinatal period. In the case of perinatal obsessive-compulsive disorder (OCD), mothers may experience unique worries in regard to their parenting or fears that their baby may be harmed. While these worries are common, they can become disruptive when persistent and impact the mother’s mood and ability to bond with the infant. Our current understanding of OCD includes the influence of genetic factors and brain changes, but little is understood about what factors may increase risk for OCD in the perinatal period. In this thesis, we aimed to review whether certain alterations within DNA segments, known as gene variants, may be linked to the development of OCD in females and if these gene changes, as well as differences in brain structures in postpartum mothers, are associated with OCD symptoms during the perinatal period. The genes we examined are important for regulating a chemical signaling substance in the brain known as serotonin. Based on our results, we did not find a relationship between serotonin gene variants and OCD symptoms in perinatal women. We also found no differences when comparing the cortical brain structures between mothers with OCD and healthy mothers; however, we observed that measures of surface area across several cortical brain regions were related to symptom worsening from pregnancy to postpartum, and also with symptom severity in postpartum mothers with OCD. These results suggest that there are widespread brain changes during the postpartum period that may increase a mother’s risk for developing OCD. Overall, the work in this thesis provides the first glimpse into potential risk factors for perinatal OCD.
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The Regulation of Brain Serotonergic and Dopaminergic Neurons: The Modulatory Effects of Selective Serotonin Reuptake Inhibitors, Atypical Neuroleptics and Environmental EnrichmentMacGillivray, Lindsey E.S. 04 1900 (has links)
<p>The brain serotonergic and dopaminergic systems broadly influence our internal experience and the ways in which we interact with the outside environment, with crucial regulatory roles in mood, sleep, appetite and the control of voluntary movement. Serotonin and dopamine neurons are themselves influenced by a wide variety of internal and external factors, many of which remain poorly understood. The central aim of this thesis was to better characterize several of these modulatory influences via exploratory investigations involving pharmaceutical agents or environmental modification. Specifically, I examined the modulatory effects of selective serotonin reuptake inhibitors (SSRIs), atypical neuroleptics and environmental enrichment with exercise on the regulation of brain serotonin and dopamine neurons.</p> <p>This thesis documents, for the first time, that (1) inhibition of the serotonin transporter (SERT) by SSRIs induces a rapid and region-selective reduction of tryptophan hydroxylase (TPH)-immunoreactive neurons in serotonergic brainstem nuclei that persists over a prolonged treatment course; that (2) selective blockade of SERT by SSRIs can rapidly induce a reduction of tyrosine hydroxylase (TH)-positive dopaminergic neurons in the substantia nigra (SN) and the ventral tegmental area (VTA) that, again, persists over a lengthy treatment course; that (3) environmental enrichment with exercise can potentiate the effect of SERT inhibition on SN dopaminergic neurons, but not the dorsal raphe nucleus (DRN) serotonergic neurons; that (4) that SSRI fluoxetine triggers a significant upregulation of microglia in the SN; that (5) environmental enrichment with exercise can reduce TPH immunoreactivity in the DRN and TH immunoreactivity in the SN and VTA, even in the absence of any pharmacological intervention, and finally, that (6) the atypical neuroleptic risperidone significantly reduces TPH in the DRN of both young and aged animals and reduces DRN Nissl counts in aged animals. Taken together, the body of work included in this thesis suggests that SSRIs, atypical neuroleptics and environmental enrichment with exercise can have profound effects on brain serotonergic and dopaminergic neurons, possibly accounting for some of the side effects and therapeutic benefits associated with these interventions.</p> / Doctor of Philosophy (PhD)
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Chiral and toxicological aspects of citalopram : an experimental study in rats /Kugelberg, Fredrik C., January 2003 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2003. / Härtill 4 uppsatser.
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Exploring the Neural-Tumor Synapse: The Effects of Serotonin on C6 Glioma CellsCoulson, Katarina Michelle 02 August 2017 (has links)
No description available.
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Die Funktionelle Rolle der Palmitilierung des 5-HT 1A Rezeptor / The Functional Role of Palmitoylation of the 5-HT 1A receptorPapoucheva, Ekaterina 03 November 2004 (has links)
No description available.
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5HT 2 Rezeptor vermittelte Kontrolle des neonatalen medullären respiratorischen Netzwerks des Säugers / 5HT 2 receptor mediated control of the medullary respiratory center in neonatal mammalsGünther, Silke Kerstin Karin 25 April 2002 (has links)
No description available.
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ASSOCIATION BETWEEN CONCOMITANT USE OF BISPHOSPHONATES AND SEROTONIN REUPTAKE INHIBITORS AND INCREASED RISK OF OSTEOPOROTIC-RELATED FRACTURES: AMONG COMMUNITY-DWELLING POSTMENOPAUSAL WOMENNyandege, Abner 01 January 2013 (has links)
Osteoporosis and depression are prevalent among older postmenopausal women 65 years or older. Bisphosphonates (BPs) and selective serotonin reuptake inhibitors (SSRIs) or serotonin norepinephrine reuptake inhibitors (SNRIs) are commonly used medications to treat these conditions. Inhibitory effects of BPs on osteoclasts are responsible for the reduction in fracture risk. SSRIs, however, are associated with increased fracture risk through decreasing osteoblasts and increasing osteoclastic activity. These effects of SSRIs could attenuate the beneficial effects of BPs. This dissertation describes the concomitant use of BPs and SSRIs among postmeopausa women and reports findings from examining the association between concomitant use of BPs and SSRIs and fracture risk. Separate cross-sectional analyses were performed using data from the 2004-2008 Medical Expenditure Panel Survey (MEPS) and Medicare Part D prescriptions claims data (2008-2010) to examine usage patterns of BPs and SSRIs/SNRIs for women aged ≥45 years and ≥65 years, respectively. For our second objective, a nested-case control was conducted using Medicare claims data (2008-2010). Data from Medicare inpatient claims were linked to Medicare Part D data for all female BP users 65 years or older. We used Cox proportional hazards model to assess the increased risk of osteoporotic-related fractures among propensity score matched (1:1 ratio) cohorts of concomitant users of BPs and SSRIs and BP alone users. Concomitant use of BPs and SSRIs was prevalent and increased with age for each timeframe examined. Findings showed that approximately 12% (using MEPS) and 28% (using Medicare data) of women on BPs were also on SSRIs. For the second objective, 4,214 propensity score matched pairs (average age=80.4 years) of subjects were analyzed. Findings showed that concomitant use of BPs and SSRIs was associated with statistically significant increased risk for any fracture (HR=1.29, 95% CI, 1.07-1.57), but statistically non-significant increased risk for hip (HR=1.16, 95% CI, 0.92-1.47) and vertebral fractures (HR=1.55, 95% CI, 0.97-2.48). Current findings indicate that concomitant use of BPs and SSRIs is not uncommon among postmenopausal women and suggest potential attenuation of antifracture efficacy of BPs by SSRIs. Further studies are needed to understand the clinical impact of concomitant use of these medications among older postmenopausal women.
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