Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
1.
Rev. bras. med. esporte ; 29: e2022_0634, 2023. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1423550

ABSTRACT

ABSTRACT Introduction: Although exercise development has shown great theoretical progress, there are still many problems regarding the current sports teaching process in physical fitness training dedicated to basketball. One of the current needs is the evaluation of the current training methods of its players and the functional introduction method in this scenario. Objective: Explore the physical characteristics and functional training methods in different positions of basketball players. Methods: A literature search was conducted to survey the current scientific practices and the athletes of the second national men's and women's basketball team who participated in a winter training from January 10 to March 10, 2019 were taken as the objects of study, also considering the different positions of the active athletes of the CBA, WCBA, NBA and WNBA. Results: The results showed that the average blood lactate level of the second national women's basketball team was 11.19mmol/L, slightly lower than the national women's team (11.8±1.2mmol/L), indicating that the athletes' anaerobic capacity reached a high level. Conclusion: Basketball players in different positions have different demands regarding physical characteristics and training methods. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.


RESUMO Introdução: Embora o desenvolvimento de exercícios tenha apresentado grandes progressos teóricos, ainda há muitos problemas quanto ao atual processo de ensino esportivo no treinamento de aptidão física dedicado ao basquetebol. Uma das necessidades atuais é a avaliação dos métodos de treinamento atual de seus jogadores e o método de introdução funcional neste cenário. Objetivo: Explorar as características físicas e os métodos de treinamento funcional em diferentes posições dos jogadores de basquetebol. Métodos: Efetuou-se uma pesquisa bibliográfica para levantamento das práticas científicas atuais e tomou-se como objetos de estudo os atletas da segunda equipe nacional masculina e feminina de basquetebol que participaram de um treinamento de inverno de 10 de janeiro a 10 de março de 2019, considerando também as diferentes posições dos atletas ativos da CBA, WCBA, NBA e WNBA. Resultados: Os resultados mostraram que o nível médio de ácido láctico no sangue das atletas da segunda equipe nacional feminina de basquetebol foi de 11,19mmol/L, o que foi ligeiramente inferior ao das atletas da seleção nacional feminina (11,8±1,2mmol/L), indicando que a capacidade anaeróbica das atletas atingiu um nível elevado. Conclusão: Jogadores de basquetebol em diferentes posições têm diferentes exigências quanto às características físicas e métodos de treinamento. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.


RESUMEN Introducción: Aunque el desarrollo de los ejercicios ha presentado un gran progreso teórico, todavía existen muchos problemas en relación con el proceso actual de educación deportiva en el entrenamiento de la condición física dedicado al baloncesto. Una de las necesidades actuales es la evaluación de los métodos actuales de entrenamiento de sus jugadores y el método de introducción funcional en este escenario. Objetivo: Explorar las características físicas y los métodos de entrenamiento funcional en diferentes posiciones de los jugadores de baloncesto. Métodos: Se realizó una búsqueda bibliográfica para sondear las prácticas científicas actuales y se tomaron como objeto de estudio los deportistas de la segunda selección nacional de baloncesto masculina y femenina que participaron en un entrenamiento de invierno del 10 de enero al 10 de marzo de 2019, considerando también las diferentes posiciones de los deportistas en activo de la CBA, WCBA, NBA y WNBA. Resultados: Los resultados mostraron que el nivel medio de ácido láctico en sangre de las atletas del segundo equipo nacional de baloncesto femenino era de 11,19mmol/L, ligeramente inferior al de las atletas del equipo nacional femenino (11,8±1,2mmol/L), lo que indica que la capacidad anaeróbica de las atletas alcanzó un nivel elevado. Conclusión: Los jugadores de baloncesto en diferentes posiciones tienen diferentes exigencias en cuanto a características físicas y métodos de entrenamiento. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

2.
Arch. endocrinol. metab. (Online) ; 66(4): 551-581, July-Aug. 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1403227

ABSTRACT

ABSTRACT Recent studies have shown that two common methylenetetrahydrofolate reductase ( MTHFR ) gene polymorphisms (C677T and A1298C) might correlate with thyroid dysfunction, but the results remain inconsistent. We carried out a meta-analysis aiming to assess the relationship of both polymorphisms with thyroid dysfunction. The PubMed, EMBASE, CNKI (China National Knowledge Infrastructure), CBMdisc (China Biology Medicine disc), WeiPu and Wanfang databases were searched up to September 2021. Case-control and cohort studies on MTHFR polymorphism and thyroid dysfunction were identified. Eight studies from six publications were finally included in our meta-analysis, including 817 patients and 566 controls. After pooled analysis, we found that the MTHFR C677T polymorphism was associated with an increased risk of hypothyroidism (TT vs. CC+CT/recessive model: OR = 2.07, 95% CI: 1.02-4.20, P = 0.04; TT vs. CC/homozygote model: OR = 2.35, 95% CI: 1.13-4.86, P = 0.02), while trial sequential analysis (TSA) revealed that it could be a false positive result. The MTHFR A1298C polymorphism was related to a decreased risk of hypothyroidism (C vs. A/allele model: OR = 0.63, 95% CI: 0.44-0.92, P = 0.02; CC vs. AC+AA/recessive model: OR = 0.42, 95% CI: 0.22-0.79, P = 0.007; CC vs. AA/homozygote model: OR = 0.43, 95% CI: 0.25-0.85, P = 0.02), which was conclusive according to TSA. The results of this meta-analysis suggest that MTHFR A1298C seems to be a protective factor for hypothyroidism, while the MTHFR C677T polymorphism may be a risk factor. However, more well-designed studies with larger sample sizes are needed to obtain more reliable results of the association between the MTHFR C677T polymorphism and hypothyroidism.

3.
Chinese Journal of Rehabilitation Theory and Practice ; (12): 197-202, 2021.
Article in Chinese | WPRIM | ID: wpr-905299

ABSTRACT

Objective:To observe the effects of pain relief after acupuncture on walking speed, step length and ground reaction force (GRF) of patients with chronic nonspecific low back pain (CNLBP) during walking. Methods:From May to December, 2019, 28 CNLBP patients were randomly divided into waiting list group (n = 14) and acupuncture group (n = 14). The acupuncture group received acupuncture, 30 minutes a time, three times a week, for four weeks. The waiting list group only received health education after enrollment until four weeks later. Gait analysis was performed with three-dimensional motion system for both groups after enrollment and one month later. The walking speed, step length and GRF characteristic values were recorded and compared, as well as Visual Analogue Score (VAS) for pain. Results:After intervention, The VAS decreased in both groups (t > 2.956, P < 0.05), and was lower in the acupuncture group than in the waiting list group (t = -2.844, P = 0.004). No significant difference in walking speed, step length and GRF characteristic values was found after intervention in both groups (P > 0.05). Conclusion:One month-acupuncture could relief the pain of CNLBP patients, however, it could not improve the performance during walking.

4.
Chinese Journal of Rehabilitation Theory and Practice ; (12): 802-806, 2020.
Article in Chinese | WPRIM | ID: wpr-905393

ABSTRACT

Surface electromyography can record the neuroelectric signals responding the activity of muscle during exercise, which has been used to observe the characteristics of trunk and lower limb muscles in patients with chronic low back pain. It may be used in the researches about pathogenesis, diagnosis and treatment of chronic low back pain by comparing the surface electromyography signals between patients and normal controls during various activities.

5.
Chinese Journal of Rehabilitation Theory and Practice ; (12): 882-885, 2019.
Article in Chinese | WPRIM | ID: wpr-905653

ABSTRACT

At present, three-dimensional gait analysis has been used in the diagnosis, treatment and rehabilitation of chronic non-specific low back pain. Existing researches have conducted systematic cross-sectional studies on the gait of patients with chronic non-specific low back pain from the aspects of space-time parameters, kinematics parameters, dynamic parameters and surface EMG, but few are about efficacy evaluation with three-dimensional gait analysis, which may be a topic in the future.

6.
Yonsei Medical Journal ; : 633-642, 2018.
Article in English | WPRIM | ID: wpr-715899

ABSTRACT

PURPOSE: To investigate the effects of Helicobacter pylori (H. pylori)-CagA and the urease metabolite NH₄⁺ on mucin expression in AGS cells. MATERIALS AND METHODS: AGS cells were transfected with CagA and/or treated with different concentrations of NH₄⁺CL. Mucin gene and protein expression was assessed by qPCR and immunofluorescence assays, respectively. RESULTS: CagA significantly upregulated MUC5AC, MUC2, and MUC5B expression in AGS cells, but did not affect E-cadherin and MUC6 expression. MUC5AC, MUC6, and MUC2 expression in AGS cells increased with increasing NH₄⁺ concentrations until reaching a peak level at 15 mM. MUC5B mRNA expression in AGS cells (NH₄⁺ concentration of 15 mM) was significantly higher than that at 0, 5, and 10 mM NH₄⁺. No changes in E-cadherin expression in AGS cells treated with NH₄⁺ were noted, except at 20 mM. The expression of MUC5AC, MUC2, and MUC6 mRNA in CagA-transfected AGS cells at an NH₄⁺ concentration of 15 mM was significantly NH₄⁺ concentration, and was significantly higher compared to that in untreated cells. No significant change in the expression of E-cadherin mRNA in CagA-transfected AGS cells was observed. Immunofluorescence assays confirmed the observed changes. CONCLUSION: H. pylori may affect the expression of MUC5AC, MUC2, MUC5B, and MUC6 in AGS cells via CagA and/or NH₄⁺, but not E-cadherin.


Subject(s)
Ammonium Chloride , Ammonium Compounds , Cadherins , Fluorescent Antibody Technique , Helicobacter pylori , Helicobacter , Mucins , RNA, Messenger , Stomach , Urease , Virulence
7.
Journal of Huazhong University of Science and Technology (Medical Sciences) ; (6): 475-485, 2017.
Article in Chinese | WPRIM | ID: wpr-333470

ABSTRACT

Endoscopic therapy (ET) is most common method for preventing variceal bleeding in cirrhosis,but the outcomes are not perfect.Recently,transjugular intrahepatic portosystemic shunt (TIPS) is introduced into clinical practice.However,the beneficial effects of TIPS compared to ET on cirrhotic patients is unknown.The aim of this study was to evaluate and compare the effects of TIPS with those of the most frequently used ET for prevention of variceal rebleeding (VRB) in liver cirrhosis.The PubMed,EMBASE,and Cochrane Library databases were searched from inception to February 2017.The primary study outcomes included the incidence of VRB,all-cause mortality,bleeding-related death,and the incidence of post-treatment hepatic encephalopathy (PTE).The odds ratios (ORs) with 95% confidence intervals (CI) were pooled for dichotomous variables.Subgroup analyses were performed.Twenty-four studies were eligible and they included 1120 subjects treated with TIPS and 1065 subjects treated with ET.Although there was no significant difference in survival and PTE,TIPS was superior to ET in decreasing the incidence of VRB (OR=0.27;95% CI,0.19-0.39,P<0.00001),and decreasing the incidence of bleeding-related death (OR=0.21;95% CI,0.13-0.32,P<0.00001).Subgroup analysis found a lower mortality (OR=0.48;95% CI,0.23-0.97;P=0.04) without any increased incidence of PTE (OR=1.37;95% CI,0.75-2.50;P=0.31) in the studies of a greater proportion (≥40%) of patients with Child-Pugh class C cirrhosis receiving TIPS,and TIPS with covered stent did not increase the risk of PTE compared to ET (OR=1.52,95% CI =0.82-2.80,P=0.18).It was concluded that TIPS with covered stent might be considered the preferred choice of therapy in patients with severe liver disease for secondary prophylaxis.

8.
Biol. Res ; 49: 1-10, 2016. ilus, graf
Article in English | LILACS | ID: biblio-950844

ABSTRACT

BACKGROUND: In China, mesangial proliferative glomerulonephritis (MsPGN) is one of the most common kidney diseases. In this study, we treated a rat model of chronic anti-Thy-1 MsPGN with Shenhua Tablet and evaluated whether the tablet was able to protect the kidney function. Thirty-six Wistar rats were randomly divided into six groups: (1) Sham surgery (Sham); (2) anti-Thy-1 nephritis model (Thy-1); (3) anti-Thy-1 nephritis model + irbesartan-treated (Irb); (4) anti-Thy-1 nephritis model + low-dose of Shenhua Tablet (SHL); (5) anti-Thy-1 nephritis model + medium-dose of Shenhua Tablet (SHM); (6) anti-Thy-1 nephritis model + high-dose of Shenhua Tablet (SHH). RESULTS: Thirteen weeks after drug treatment, urinary proteins were quantified and renal pathological changes were thoroughly examined at the time point of 24 h. Meanwhile, the expression levels of p-Erk1/2, cyclin D1 and p21 at the renal cortex were also tested. The levels of urinary proteins and total cholesterol in the blood were significantly reduced in rats treated with any drug tested in this study. The level of triglyceride was significantly reduced in all three Shenhua Tablet-treated groups. Renal pathomorphological scores were significantly improved in groups of Irb, SHM and SHH. Mesangial cell proliferation was significantly inhibited in any drug-treated group. p-Erk1/2 and cyclin D1 were downregulated whereas p21 was upregulated in the renal cortex. CONCLUSIONS: Our study indicated that Shenhua Tablet is able to inhibit the abnormal proliferation of mesangial cells and to prevent kidney damage, which is likely associated with downregulation of p-Erk1/2 and reduced activity of its downstream target-cyclin D1.


Subject(s)
Animals , Male , Drugs, Chinese Herbal/pharmacology , Glomerulonephritis, Membranoproliferative/drug therapy , Cell Proliferation/drug effects , Mesangial Cells/drug effects , Isoantibodies , Time Factors , Serum Albumin/analysis , Drugs, Chinese Herbal/therapeutic use , Glomerulonephritis, Membranoproliferative/pathology , Chronic Disease , Reproducibility of Results , Rats, Wistar , Mitogen-Activated Protein Kinase 1/analysis , Cyclin D1/analysis , Computers, Handheld , p21-Activated Kinases/analysis
9.
Rev. méd. Chile ; 142(2): 255-260, feb. 2014. ilus
Article in English | LILACS | ID: lil-710996

ABSTRACT

Lupus peritonitis (LP) is extremely rare. Acute LP is characterized by rapid onset of ascites and severe abdominal pain, in addition to other well-recognized clinical features of a general systemic lupus erythematosus (SLE) fare. Ascites associated with acute LP has been rarely reported as the prominent feature of a SLE fare. We report a 39-year-old woman who developed massive, painful ascites as the presenting manifestation of a SLE fare. Diagnostic workup ruled out the possibility of hepatic, cardiovascular, infectious, or malignant diseases, and confirmed the presence of a SLE fare. The patient was treated with methyl prednisolone and hydroxychloroquine resulting in dramatic improvement of her condition. During ambulatory follow up, she has remained asymptomatic up to the moment of this writing. Adrenal steroids and hydrocychloroquine may be useful for the management of SLE fares in patients with massive, painful ascites due to acute LP.


La peritonitis lúpica es rara. El cuadro agudo se caracteriza por ascitis de comienzo rápido, dolor abdominal severo y otras manifestaciones de una recidiva de un lupus eritematoso sistémico (LES). Sólo ocasionalmente e ha informado que la ascitis y peritonitis lúpica sean las principales manifestaciones de una recidiva lúpica. Presentamos a una mujer de 39 años que presentó ascitis masiva y dolorosa como la primera manifestación de una reactivación lúpica. El estudio diagnóstico descartó problemas hepáticos, pulmonares, cardiacos, cáncer o infecciones y confirmó la reactivación lúpica. La paciente se trató con metilprednisolona y cloroquina, resultando en una mejoría dramática. Al momento de preparar este informe, la paciente permanece asintomática en control ambulatorio. Los corticoides y cloroquina pueden ser medicamentos útiles para el tratamiento de pacientes con ascitis dolorosa y masiva secundaria a peritonitis lúpica.


Subject(s)
Adult , Female , Humans , Ascites/etiology , Lupus Erythematosus, Systemic/complications , Peritonitis/etiology , Ascites/diagnosis , Peritonitis/diagnosis , Tomography, X-Ray Computed
10.
Clinics ; 68(11): 1428-1432, 1jan. 2013. tab
Article in English | LILACS | ID: lil-690627

ABSTRACT

OBJECTIVE: The angiotensin-converting enzyme gene is one of the most studied candidate genes related to atrial fibrillation. Among the polymorphisms of the angiotensin-converting enzyme gene, the 2350 G/A polymorphism (rs4343) is known to have the most significant effects on the plasma angiotensin-converting enzyme concentration. The aim of the present study was to investigate the association of the angiotensin-converting enzyme 2350 G/A polymorphism with atrial fibrillation in Han Chinese patients with essential hypertension. METHODS: A total of 169 hypertensive patients were eligible for this study. Patients with atrial fibrillation (n = 75) were allocated to the atrial fibrillation group, and 94 subjects without atrial fibrillation were allocated to the control group. The PCR-based restriction fragment length polymorphism technique was used to assess the genotype frequencies. RESULTS: The distributions of the angiotensin-converting enzyme 2350 G/A genotypes (GG, GA, and AA, respectively) were 40.43%, 41.49%, and 18.08% in the controls and 18.67%, 46.67%, and 34.66% in the atrial fibrillation subjects (p = 0.037). The frequency of the A allele in the atrial fibrillation group was significantly greater than in the control group (58.00% vs. 38.83%, p = 0.0007). Compared with the wild-type GG genotype, the GA and AA genotypes had an increased risk for atrial fibrillation. Additionally, atrial fibrillation patients with the AA genotype had greater left atrial dimensions than the patients with the GG or GA genotypes (p<0.01 and p<0.05, respectively). CONCLUSIONS: The results obtained in this study indicate that the angiotensin-converting enzyme 2350 G/A polymorphism is associated with atrial fibrillation and that the A allele shows an increased risk for atrial fibrillation in Han Chinese patients with essential hypertension. .


Subject(s)
Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Atrial Fibrillation/genetics , Hypertension/genetics , Peptidyl-Dipeptidase A/genetics , Polymorphism, Genetic/genetics , Age Factors , Asian People/genetics , Body Mass Index , Blood Pressure/genetics , China , Gene Frequency , Genetic Predisposition to Disease , Polymerase Chain Reaction , Risk Factors , Sex Factors
11.
Chinese Journal of Virology ; (6): 131-136, 2009.
Article in Chinese | WPRIM | ID: wpr-334734

ABSTRACT

To examine the phylogenetic information regarding the gene pool of AIV in domestic ducks in eastern China, the NA genes of twenty-six viruses isolated during 2002-2006, including two H1N1 strains, tenH3N1 strains and fourteen HSN1 strains, which reflected the predominant N1 subtype viruses were subjected to phylogenetic analysis. The results indicated that AIVs of N1 subtype circulating in domestic ducks in eastern China were undergoing a gradual evolution. Analysis of the deduced amino acid sequences revealed that NAs from all isolated H5N1 viruses had a 20-aa deletion in the stalk region (residues 49-68), whereas no deletion was seen in the NAs from other HA subtype viruses. The viruses of H3N1 and H1N1 might have a propensity for reassortment of NA genes, whereas no direct evidence of reassortment of NA gene was obtained in H5N1 viruses.


Subject(s)
Animals , Humans , Birds , China , DNA, Viral , Evolution, Molecular , Influenza A Virus, H1N1 Subtype , Classification , Genetics , Influenza A Virus, H3N2 Subtype , Classification , Genetics , Influenza A Virus, H5N1 Subtype , Classification , Genetics , Influenza A virus , Classification , Genetics , Influenza in Birds , Virology , Influenza, Human , Virology , Neuraminidase , Genetics , Phylogeny , Poultry Diseases , Virology , Sequence Alignment , Sequence Deletion
12.
Chinese Medical Journal ; (24): 112-117, 2008.
Article in English | WPRIM | ID: wpr-255756

ABSTRACT

<p><b>BACKGROUND</b>Scavenger receptor that binds phosphatidylserine and oxidized lipoprotein/CXC chemokine ligand 16 (SR-PSOX/CXCL16) promotes foam cell formation through the tumor necrosis factor (TNF)-alpha mediated mechanism. Because chemokine CXCL16 could be expressed in atherosclerotic lesions and induce smooth muscle cell (SMC) proliferation, we presume that the monocyte SR-PSOX/CXCL16 detection in the patients' peripheral blood will be important for early diagnosis and prognosis of atherosclerosis (AS).</p><p><b>METHODS</b>Enrolled in this study were 40 patients with acute coronary syndrome (ACS), including 20 patients with acute myocardial infarction (AMI) and 20 patients with unstable angina pectoris (UAP), and 20 normal controls. Monocytes in the peripheral blood were isolated, and the changes of expression of CXCL16/SR-PSOX mRNA were compared using reverse transcription-polymerase chain reaction (RT-PCR), with beta-actin as internal control. We compared the expression of CXCL16/SR-PSOX in the ACS subgroups, using Western-blot to analyze protein expression levels. Tissue sections were made from biopsy specimens taken from patients with infective endocarditis, liver cirrhosis, and lung cancer as well as normal controls. And the expression of CXCL16/SR-PSOX was analyzed with a confocal microscope.</p><p><b>RESULTS</b>The expression of CXCL16/SR-PSOX mRNA and protein in the monocytes of peripheral blood was significantly higher in ACS patients than in normal controls (P < 0.05); however, there was no significant difference in CXCL16/SR-PSOX expression between UAP group and AMI group (P > 0.05). Immunofluorescence showed that there were low expression of SR-PSOX in normal vascular endothelial cells and enhanced expression in every layer of the infected vessels, while spreading from endothelial cells to surrounding tissues as infection worsens. Confocal microscopy showed that the expression of SR-PSOX was enhanced in the infiltrated lymphocytes in liver cirrhosis, and that the expression level was proportionate to the degree of inflammation in the portal hepatis and folia.</p><p><b>CONCLUSIONS</b>The expression of CXCL16/SR-PSOX in the monocytes of peripheral blood was significantly higher in ACS patients than in the controls. CXCL16/SR-PSOX-mediated inflammation may contribute to the pathogenesis of ACS, and CXCL16 may play an important role in the pathogenesis and development of AS in humans.</p>


Subject(s)
Humans , Acute Coronary Syndrome , Allergy and Immunology , Blotting, Western , Chemokine CXCL16 , Chemokines, CXC , Blood , Genetics , Coronary Angiography , Fluorescent Antibody Technique , RNA, Messenger , Blood , Receptors, Scavenger , Blood , Genetics
13.
Genet. mol. biol ; 28(4): 821-826, Dec. 2005. ilus, tab
Article in English | LILACS | ID: lil-450992

ABSTRACT

Chitinase plays a positive role in the pathogenicity of Bacillus thuringiensis to insect pests. We used touchdown PCR to clone the chitinase (Schi) gene from Bacillus thuringiensis serovar sotto (Bt sotto) chromosomal DNA. Our DNA sequencing analysis revealed that the Bt sotto Schi gene consists of an open reading frame (ORF) of 2067 nucleotides with codes for the chitinase precursor. We also found that the putative promoter consensus sequences (the -35 and -10 regions) of the Bt soto Schi gene are identical to those of the chiA71 gene from Bt Pakistani, the chiA74 gene from Bt kenyae and the ichi gene from Bt israelensis. The Schi chitinase precursor is 688 amino acids long with an estimated molecular mass of 75.75 kDa and a theoretical isoelectric point of 5.74, and contains four domains, which are, in sequence, a signal peptide, an N-terminal catalytic domain, a fibronectin type III like domain and a C-terminal chitin-binding domain. Sequence comparison and the evolutionary relationship of the Bt sotto Schi chitinase to other chitinase and chitinase-like proteins are also discussed


Subject(s)
Animals , Bacillus thuringiensis/genetics , Cloning, Molecular , Chitinases/genetics , Insecta , Polymerase Chain Reaction , Sequence Analysis, DNA
14.
In. II International Congress on Neuroregeneration. Proceedings (selected papers). Rio de Janeiro, UFRJ, 2004. p.17-20, ilus, tab.
Monography in English | LILACS | ID: lil-682588

ABSTRACT

Amyloid-Beta (Aβ) accumulation and aggregation are thought to contribute to the pathogenesis of Alzheimer’s disease (AD). In AD, there also is a selective decrease in numbers of radioligand binding sites corresponding to the most abundant nicotinic acetylcholine receptor (nAChR) subtype, which contains human α4 and β2 subunits (α4β2-nAChR). However, relationships between these phenomena are uncertain, and effects of Aβ on human α4β2-nAChR function have not been investigated in detail. We created SH-EP1 cells stably transfected to heterologously express human α4β2- or α7-nAChR subtypes. Whole-cell current recording confirmed heterologous expression of functional α4β2-nAChR with characteristic responses to nicotinic agonists or antagonists. Nicotine-induced whole-cell currents were suppressed by Aβ1−42 in a dose-dependent manner. Functional inhibition was selective for Aβ1−42 compared to functionally-inactive, control peptide Aβ40-1, but was mimicked by Aβ1-40. Aβ1-42-mediated inhibition of α4β2-nAChR function was non-competitive, voltage¬independent, and use-independent. Pre-loading of cells with GDP-β-S failed to prevent Aβ1-42 –induced inhibition, suggesting that the down-regulation of α4β2-nAChR function by Aβ1-42 is not mediated by nAChR internalization. Sensitivity to Aβ1-42 antagonism at 1 nM was evident for α4β 2-nAChR, but not for heterologously expressed, human α7-nAChR, although both nAChR subtypes were functionally inhibited by 100 nM Aβ1-42, with the magnitude of functional block being higher for 100 nM Aβ1-42 acting at α7-nAChR. These findings suggest that α4β2-nAChR are sensitive and perhaps pathophysiologically-relevant targets for Aβ neurotoxicity in AD.


Subject(s)
Acetylcholine , Alzheimer Disease , Amyloid beta-Peptides , Neurology , Nicotine
SELECTION OF CITATIONS
SEARCH DETAIL