Search results for " serotonin"
showing 10 items of 140 documents
Central Serotonin2C Receptor: From Physiology to Pathology
2006
Since the 1950s, when serotonin (5-HT) was discovered in the mammalian central nervous system (CNS), an enormous amount of experimental evidence has revealed the pivotal role of this biogenic amine in a number of cognitive and behavioural functions. Although 5-HT is synthesized by a small group of neurons within the raphe nuclei of the brain stem, almost all parts of the CNS receive serotonergic projections. Furthermore, the importance of 5-HT modulation and the fine-tuning of its action is underlined by the large number of 5-HT binding sites found in the CNS. Hitherto, up to 15 different 5-HT receptors subtypes have been identified. This review was undertaken to summarize the work that has…
Nanosensor for Sensitive Detection of the New Psychedelic Drug 25I-NBOMe.
2020
[EN] This work reports the synthesis, characterization, and sensing behavior of a hybrid nanodevice for the detection of the potent abuse drug 25I-NBOMe. The system is based on mesoporous silica nanoparticles, loaded with a fluorescent dye, functionalized with a serotonin derivative and capped with the 5-HT2A receptor antibody. In the presence of 25I-NBOMe the capping antibody is displaced, leading to pore opening and rhodamine B release. This delivery was ascribed to 5-HT2A receptor antibody detachment from the surface due to its stronger coordination with 25I-NBOMe present in the solution. The prepared nanodevice allowed the sensitive (limit of detection of 0.6 mm) and selective recogniti…
Altered host behaviour and brain serotonergic activity caused by acanthocephalans: evidence for specificity
2006
Manipulative parasites can alter the phenotype of intermediate hosts in various ways. However, it is unclear whether such changes are just by-products of infection or adaptive and enhance transmission to the final host. Here, we show that the alteration of serotonergic activity is functionally linked to the alteration of specific behaviour in the amphipodGammarus pulexinfected with acanthocephalan parasites.Pomphorhynchus laevisand, to a lesser extent,Pomphorhynchus tereticollisaltered phototactism, but not geotactism, inG. pulex, whereas the reverse was true forPolymorphus minutus. Serotonin (5-hydroxytryptamine, 5-HT) injected to uninfectedG. pulexmimicked the altered phototactism, but ha…
Endotoxaemia resulting from decreased serotonin tranporter (5-HTT) function: A reciprocal risk factor for depression and insulin resistance?
2015
International audience; Depression and diabetes are serious diseases with an increasing global prevalence. Intriguingly, recent meta-analyses have highlighted an asymmetrical relationship between the two conditions as depressed patients were found to display a higher risk of developing type 2 diabetes than those individuals suffering from diabetes are to become depressed. Based on recent findings, we favor a hypothesis where by decreased peripheral serotonin (5-HT) transporter (5-HTT) function is a reciprocal risk factor for the comorbidity of depression and diabetes, as it can trigger inflammatory pathogenetic mechanisms of both conditions. Higher intestinal levels of 5-HT and 5-HT3 recept…
The effects of metoclopramide on acetylcholine release and on smooth muscle response in the isolated guinea-pig ileum
1982
The effects of metoclopramide on smooth muscle contraction and on release of acetylcholine were studied in the guinea-pig myenteric plexus longitudinal muscle preparation. Acetylcholine was determined either as endogenous acetylcholine, or as labelled transmitter from strips preloaded with 3H-choline. Metoclopramide caused an increase in resting tension of longitudinal muscle as well as an increase in resting output of either endogenous or labelled acetylcholine. Tetrodotoxin abolished the metoclopramide-evoked increase in transmitter release. The increase in smooth muscle tension was clearly related to the increase in resting output. The effects of metoclopramide on both longitudinal muscl…
Antidepressants are functional antagonists at the serotonin type 3 (5-HT3) receptor
2003
Antidepressants are commonly supposed to enhance serotonergic and/or noradrenergic neurotransmission by inhibition of neurotransmitter reuptake through binding to the respective neurotransmitter transporters or through inhibition of the monoamine oxidase. Using the concentration-clamp technique and measurements of intracellular Ca2+, we demonstrate that different classes of antidepressants act as functional antagonists at the human 5-HT3A receptor stably expressed in HEK 293 cells and at endogenous 5-HT3 receptors of rat hippocampal neurons and N1E-115 neuroblastoma cells. The tricyclic antidepressants desipramine, imipramine, and trimipramine, the serotonin reuptake inhibitor fluoxetine, t…
Feeding the brain: the importance of nutrients for brain functions and health
2017
‘We are what we eat’, said the philosopher Feuerbach. In fact, the quality of the food we eat affects our mind as well: the brain, which represents 2% of our body weight, consumes about 20% of the calories we eat each day. Follow a few rules could therefore help to feed properly our brain, so it works to the best of its ability. It is important to know properties of foods especially regarding their aminoacidic composition because aminoacids are components of neurotransmitters, molecules needed for brain transmission and function. It is also possible to choose specific food to prevent or support different diseases that affects nervous system.
Effect of the serotonin transporter gene and of environment on the continuity of anxiety and depression traits throughout adolescence
2014
Aims.Many studies of various stress reactive phenotypes suggest that 5-HTTLPR short allele carriers (S-carriers) are characterised by the stable trait of negative affectivity that is converted to psychopathology only under conditions of stress. In this study, we examined the moderating role of the 5-HTTLPR on the relationship between two objective chronic risk factors, i.e. socioeconomic status (SES) and family structure, and internalising symptoms across adolescence.Methods.A multigroup path analysis was employed in a general adolescent population sample of a 5-year follow-up study.Results.Internalising problems were significantly more stable in theS-carriers. The focus on the main dimensi…
Diagnostic techniques and multidisciplinary approach in idiopathic granulomatous mastitis: A revision of the literature
2019
Idiopathic granulomatous mastitis (IGM) is a chronic benign inflammatory disease of the breast that may mimic breast cancer. It is most common in parous young fertile women, although it can occur in nulliparous women and in men. IGM is an idiopathic disease due to the influence of some environmental factors in genetically predisposed subjects. Several pathogenic hypothesis have been proposed in the last years (autoimmune, hormonal, infective genesis). IGM presents as a painful palpable mass located in one of the two udders. The skin is usually normal but could present signs of inflammation with or without lymph nodes involvement. Ultrasonography, mammography, magnetic resonance can be diagn…
Systematic screening for mutations in the human serotonin-2A (5-HT2A) receptor gene: Identification of two naturally occurring receptor variants and …
1996
A statistically significant association between a silent mutation (102T/C) in the serotonin-2A (5-HT2A) receptor gene and schizophrenia has recently been reported in a sample of Japanese patients and healthy controls. This finding suggests that genetic predisposition to schizophrenia may be affected by a functional 5-HT2A receptor variant that is in linkage disequilibrium with 102T/C. In the present study, we have sought to identify genetic variation in the 5-HT2A receptor gene by screening genomic DNA samples from 91 unrelated subjects comprising 45 patients with schizophrenia and 46 healthy controls by using single-strand conformation analysis. We have identified four nucleotide sequence …