scholarly journals Blockage of High-Affinity Choline Transporter Increases Visceral Hypersensitivity in Rats with Chronic Stress

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Chen Zhao ◽  
Mengjuan Lin ◽  
Yasi Pan ◽  
Baoping Yu
Keyword(s):  
Normal Saline ◽  
Specific Inhibitor ◽  
Visceral Hypersensitivity ◽  
Choline Uptake ◽  
Uptake System ◽  
Threshold Intensity ◽  
Choline Transporter ◽  
High Affinity ◽  
Acetylcholine Concentration ◽  
High Affinity Choline Transporter

Background. Visceral hypersensitivity is a common feature of irritable bowel syndrome. Cholinergic system involves in the development of visceral hypersensitivity, and high-affinity choline transporter (CHT1) is of crucial importance in choline uptake system. However, involvement of CHT1 in visceral hypersensitivity remains unknown. The research aimed to study the CHT1 expression in dorsal root ganglions (DRGs) and the role of CHT1 in visceral hypersensitivity. Methods. Repetitive water avoidance stress (WAS) was used to induce visceral hypersensitivity in rats. Colorectal distension (CRD) was determined, and the abdominal withdrawal reflex (AWR) and threshold intensity data were recorded to measure the visceral sensitivity. After intraperitoneal injection of hemicholinium-3 (HC-3), the specific inhibitor of CHT1, CRD data were also recorded. The CHT1 expression of DRGs was investigated by Western blotting, immunohistochemistry, and quantitative RT-PCR. Acetylcholine levels in the DRGs were detected by the assay kit. Results. Repetitive WAS increased the AWR score of CRD at high distension pressure and decreased the mean threshold of rats. The CHT1 expression and acetylcholine concentration of DRG were significantly increased in WAS rats. After the administration of HC-3, the AWR score in WAS group was significantly increased at higher distension pressure while the threshold intensity was significantly reduced compared to the normal saline group. Acetylcholine concentration was significantly lower than the normal saline rats. Conclusion. Our research firstly reports that CHT1 is overexpressed in noninflammatory visceral hypersensitivity, and blockage of CHT1 can enhance the visceral hypersensitivity. CHT1 may play an inhibitory role in visceral hypersensitivity.

scholarly journals Syntheses and In-vitro Evaluation of Tetrahydroaminoacridine (THA) Based Analogues as High Affinity Choline Transporter (HAChT) Imaging Probe

2016 ◽  
Vol 17 (2) ◽  
pp. 97-102
Author(s):  
Mohammad Anwar Ul Azim ◽  
Takashi Kozaka ◽  
Izumi Uno ◽  
Daisuke Miwa ◽  
Yoji Kitamura ◽  
...  
Keyword(s):  
Binding Assay ◽  
Research Work ◽  
Cholinergic Neurons ◽  
Choline Uptake ◽  
Choline Transporter ◽  
High Affinity ◽  
20 Nm ◽  
High Affinity Choline Transporter

Introduction: In cholinergic neurons, high affinity choline uptake (HACU) by the high affinity choline transporter (HAChT) is a rate-limiting and regulatory step for the synthesis of Acetylcholine (Ach).Thus, HAChT appear to be a relatively specific presynaptic marker for cholinergic neurons in Alzheimer’s disease.Objectives: The principle objective of the study is to check the affinity of tetrahydroaminoacridine (THA) derivatives for HAChT. Another objective of the research work is to clarify whether the hemicholinium-3 (ChT inhibitor) and HACU enhancer molecules share the same binding sites or not.Materials and Methods: The inhibition activities of tacrine, the 2,3-dimethylfuran derivative of tacrine (DMTA) and their corresponding 2-oxo-1-pyrrolidineacetyl derivatives, namely PTAA and MKC-231 were measured by displacement of a typical HAChT antagonist [3H]HC-3 in rat cerebral membrane. The percentage of inhibition against the binding of [3H]HC-3 to HAChT were calculated using GraphPad Prism v4 software.Results: Hemicholinium-3 showed affinity for HAChT (IC50 = 20 nM) in the in vitro binding assay. A very insignificant inhibition activity (IC50 = 1000 nM) of Tacrine was revealed. The newly synthesized tacrine derivatives, DMTA and PTAA did not show any affinity for HAChT. Although MKC-231 was reported to enhance cholinergic activity at synaptic terminals, it did not show any affinity for the HAChT in [3H]HC-3 binding assay.Conclusion: In vitro [3H]HC-3 binding assay revealed no affinity of MKC-231, tacrine and its corresponding2-oxo-1-pyrrolidineacetate derivative towards HAChT. So, it is worthy to develop radiolabeled HC-3 derivatives with high affinity for HAChT, which can diffuse the BBB, to enable the in vivo investigation of HACU system.Bangladesh J. Nuclear Med. 17(2): 97-102, July 2014

Localisation of the high-affinity choline transporter-1 in the rat skeletal motor unit

2002 ◽  
Vol 307 (3) ◽  
pp. 275-280 ◽  
Author(s):  
Katrin Lips ◽  
Uwe Pfeil ◽  
Rainer Haberberger ◽  
Wolfgang Kummer
Keyword(s):  
Motor Unit ◽  
Choline Transporter ◽  
High Affinity ◽  
High Affinity Choline Transporter

scholarly journals The Sinorhizobium meliloti ABC Transporter Cho Is Highly Specific for Choline and Expressed in Bacteroids from Medicago sativa Nodules

2004 ◽  
Vol 186 (18) ◽  
pp. 5988-5996 ◽  
Author(s):  
Laurence Dupont ◽  
Isabelle Garcia ◽  
Marie-Christine Poggi ◽  
Geneviève Alloing ◽  
Karine Mandon ◽  
...  
Keyword(s):  
Medicago Sativa ◽  
Abc Transporter ◽  
Sinorhizobium Meliloti ◽  
Lipid Membrane ◽  
Site Directed Mutagenesis ◽  
Choline Uptake ◽  
Uptake System ◽  
Choline Transport ◽  
High Affinity ◽  
Uptake Activity

ABSTRACT In Sinorhizobium meliloti, choline is the direct precursor of phosphatidylcholine, a major lipid membrane component in the Rhizobiaceae family, and glycine betaine, an important osmoprotectant. Moreover, choline is an efficient energy source which supports growth. Using a PCR strategy, we identified three chromosomal genes (choXWV) which encode components of an ABC transporter: ChoX (binding protein), ChoW (permease), and ChoV (ATPase). Whereas the best homology scores were obtained with components of betaine ProU-like systems, Cho is not involved in betaine transport. Site-directed mutagenesis of choX strongly reduced (60 to 75%) the choline uptake activity, and purification of ChoX, together with analysis of the ligand-binding specificity, showed that ChoX binds choline with a high affinity (K D , 2.7 μM) and acetylcholine with a low affinity (K D , 145 μM) but binds none of the betaines. Uptake competition experiments also revealed that ectoine, various betaines, and choline derivatives were not effective competitors for Cho-mediated choline transport. Thus, Cho is a highly specific high-affinity choline transporter. Choline transport activity and ChoX expression were induced by choline but not by salt stress. Western blotting experiments with antibodies raised against ChoX demonstrated the presence of ChoX in bacteroids isolated from nitrogen-fixing nodules obtained from Medicago sativa roots. The choX mutation did not have an effect on growth under standard conditions, and neither Nod nor Fix phenotypes were impaired in the mutant, suggesting that the remaining choline uptake system(s) still present in the mutant strain can compensate for the lack of Cho transporter.

Sign in / Sign up

Export Citation Format

Share Document