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1.
BMC Neurosci ; 19(1): 77, 2018 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-30497382

RESUMEN

BACKGROUND: The treatment of Parkinson's disease is often complicated by levodopa-induced dyskinesia (LID). Nicotinic acetylcholine receptor agonists can alleviate LID in animal models but may be less effective in conditions of severe dopaminergic denervation. While the mechanisms of LID remain incompletely understood, elevated corticostriatal levels of the brain-derived neurotrophic factor (BDNF) have been suggested to play a role. Here, female mice with near-total unilateral 6-hydroxydopamine-induced nigrostriatal lesions were chronically treated with levodopa, and the effects of the α7 nicotinic receptor partial agonist AZD0328 and nicotine on LID were assessed. At the end of the experiment, BDNF protein levels in the prefrontal cortex and striatum were measured. RESULTS: Five-day treatments with three escalating doses of AZD0328 and a 10-week treatment with nicotine failed to alleviate LID. BDNF levels in the lesioned striatum correlated positively with LID severity, but no evidence was found for a levodopa-induced elevation of corticostriatal BDNF in the lesioned hemisphere. The nicotine treatment decreased BDNF levels in the prefrontal cortex but had no effect on striatal BDNF. CONCLUSIONS: The findings suggest that treatment of LID with nicotinic agonists may lose its effectiveness as the disease progresses, represent further evidence for a role for BDNF in LID, and expand previous knowledge on the effects of long-term nicotine treatment on BDNF.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Dopaminérgicos/farmacología , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Discinesia Inducida por Medicamentos/metabolismo , Agonistas Nicotínicos/farmacología , Trastornos Parkinsonianos/tratamiento farmacológico , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Dopamina/deficiencia , Dopaminérgicos/efectos adversos , Discinesia Inducida por Medicamentos/patología , Femenino , Furanos/farmacología , Levodopa/efectos adversos , Levodopa/farmacología , Ratones Endogámicos C57BL , Nicotina/farmacología , Trastornos Parkinsonianos/metabolismo , Trastornos Parkinsonianos/patología , Quinuclidinas/farmacología , Distribución Aleatoria , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
2.
Alcohol Clin Exp Res ; 40(2): 329-34, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26842251

RESUMEN

BACKGROUND: The aim of this study was to examine possible differences in nicotinic acetylcholine receptors and responses in rats with genetic preference or avoidance for alcohol. This was done by using 2 rat lines with high alcohol preference (Alko Alcohol [AA]) or alcohol avoidance (Alko Non-Alcohol [ANA]). METHODS: Locomotor activity was measured following nicotine and histamine H3 receptor (H3R) antagonist treatment. In situ hybridization and receptor ligand binding experiments were used in drug-naïve animals to examine the expression of different α nicotinic receptor subunits. RESULTS: The AA rats were found to be more sensitive to the stimulatory effect of a low dose of nicotine than ANA rats, which were not significantly activated. Combination of histamine H3R antagonist, JNJ-39220675, and nicotine resulted to similar locomotor activation as nicotine alone. To further understand the mechanism underlying the difference in nicotine response in AA and ANA rats, we studied the expression of α5, α6, and α7 nicotinic receptor subunits in specific brain areas of AA and ANA rats. We found no differences in the expression of α5 nicotinic receptor subunits in the medial habenula and hippocampus or in α6 subunit in the ventral tegmental area and substantia nigra. However, the level of α7 nicotinic receptor subunit mRNA was significantly lower in the tuberomamillary nucleus of posterior hypothalamus of alcohol-preferring AA rats than in alcohol-avoiding ANA rats. Also the hypothalamic [125I-α-bungarotoxin binding was lower in AA rats indicating lower levels of α7 nicotinic receptors. CONCLUSIONS: The lower expression and receptor binding of α7 nicotinic receptors in the tuberomamillary nucleus of AA rats suggest a difference in the regulation of brain histamine neurons between the rat lines since the α7 nicotinic receptors are located in histaminergic neurons. Stronger nicotine-induced locomotor response, mediated partially via α7 receptors, and previously described high alcohol consumption in AA rats could be explained by the found difference in tuberomamillary α7 receptor levels.


Asunto(s)
Consumo de Bebidas Alcohólicas/fisiopatología , Hipotálamo/fisiología , Nicotina/farmacología , Receptor Nicotínico de Acetilcolina alfa 7/fisiología , Abstinencia de Alcohol , Animales , Azepinas/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Área Hipotalámica Lateral/química , Área Hipotalámica Lateral/fisiología , Hipotálamo/química , Hibridación in Situ , Masculino , Actividad Motora/efectos de los fármacos , Nicotina/administración & dosificación , Piridinas/farmacología , Ratas , Receptor Nicotínico de Acetilcolina alfa 7/análisis , Receptor Nicotínico de Acetilcolina alfa 7/antagonistas & inhibidores , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
3.
J Neurochem ; 130(2): 185-98, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24661093

RESUMEN

Nicotinic acetylcholine receptors (nAChR) of the α6ß2* subtype (where *indicates the possible presence of additional subunits) are prominently expressed on dopaminergic neurons. Because of this, their role in tobacco use and nicotine dependence has received much attention. Previous studies have demonstrated that α6ß2*-nAChR are down-regulated following chronic nicotine exposure (unlike other subtypes that have been investigated - most prominently α4ß2* nAChR). This study examines, for the first time, effects across a comprehensive chronic nicotine dose range. Chronic nicotine dose-responses and quantitative ligand-binding autoradiography were used to define nicotine sensitivity of changes in α4ß2*-nAChR and α6ß2*-nAChR expression. α6ß2*-nAChR down-regulation by chronic nicotine exposure in dopaminergic and optic-tract nuclei was ≈three-fold more sensitive than up-regulation of α4ß2*-nAChR. In contrast, nAChR-mediated [(3) H]-dopamine release from dopamine-terminal region synaptosomal preparations changed only in response to chronic treatment with high nicotine doses, whereas dopaminergic parameters (transporter expression and activity, dopamine receptor expression) were largely unchanged. Functional measures in olfactory tubercle preparations were made for the first time; both nAChR expression levels and nAChR-mediated functional measures changed differently between striatum and olfactory tubercles. These results show that functional changes measured using synaptosomal [(3) H]-DA release are primarily owing to changes in nAChR, rather than in dopaminergic, function. This study examined dose-response relationships for murine α6ß2*-nicotinic acetylcholine receptor (nAChR) down-regulation by chronic nicotine treatment. The ID50 value for α6ß2* down-regulation (35 nM) is ≈ 3x lower than the ED50 value for α4ß2* nAChR up-regulation (95 nM), both well within the range reached by human smokers. Chronic nicotine treatment altered α6ß2*- and α4ß2*-nAChR-mediated [(3) H]-dopamine release from striatal and olfactory tubercle synaptosomes, but dopaminergic parameters were largely unaffected. We conclude that functional changes are primarily driven by altered nAChR activity.


Asunto(s)
Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Receptores Nicotínicos/efectos de los fármacos , Alcaloides/farmacología , Animales , Autorradiografía , Azocinas/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Técnicas In Vitro , Ratones , Ratones Noqueados , Neostriado/citología , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Bulbo Olfatorio/citología , Bulbo Olfatorio/efectos de los fármacos , Bulbo Olfatorio/metabolismo , Piridinas/metabolismo , Piridinas/farmacología , Quinolizinas/farmacología , Ensayo de Unión Radioligante , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo
4.
Nicotine Tob Res ; 14(6): 720-33, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22241830

RESUMEN

INTRODUCTION: The role of the nicotinic acetylcholine receptor gene cluster on chromosome 15q24-25 in the etiology of nicotine dependence (ND) is still being defined. In this study, we included all 15 tagging single nucleotide polymorphisms (SNPs) within the CHRNA5-CHRNA3-CHRNB4 cluster and tested associations with 30 smoking-related phenotypes. METHODS: The study sample was ascertained from the Finnish Twin Cohort study. Twin pairs born 1938-1957 and concordant for a history of cigarette smoking were recruited along with their family members (mainly siblings), as part of the Nicotine Addiction Genetics consortium. The study sample consisted of 1,428 individuals (59% males) from 735 families, with mean age 55.6 years. RESULTS: We detected multiple novel associations for ND. DSM-IV ND symptoms associated significantly with the proxy SNP Locus 1 (rs2036527, p = .000009) and Locus 2 (rs578776, p = .0001) and tolerance factor of the Nicotine Dependence Syndrome Scale (NDSS) showed suggestive association to rs11636753 (p = .0059), rs11634351 (p = .0069), and rs1948 (p = .0071) in CHRNB4. Furthermore, we report significant association with DSM-IV ND diagnosis (rs2036527, p = .0003) for the first time in a Caucasian population. Several SNPs indicated suggestive association for traits related to ages at smoking initiation. Also, rs11636753 in CHRNB4 showed suggestive association with regular drinking (p = .0029) and the comorbidity of depression and ND (p = .0034). CONCLUSIONS: We demonstrate novel associations of DSM-IV ND symptoms and the NDSS tolerance subscale. Our results confirm and extend association findings for other ND measures. We show pleiotropic effects of this gene cluster on multiple measures of ND and also regular drinking and the comorbidity of ND and depression.


Asunto(s)
Familia de Multigenes , Proteínas del Tejido Nervioso/genética , Receptores Nicotínicos/genética , Tabaquismo/genética , Edad de Inicio , Alelos , Cromosomas Humanos Par 15/genética , Cromosomas Humanos Par 15/metabolismo , Estudios de Cohortes , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Frecuencia de los Genes , Sitios Genéticos , Pleiotropía Genética , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/metabolismo , Fenotipo , Polimorfismo de Nucleótido Simple , Receptores Nicotínicos/metabolismo , Fumar/genética , Tabaquismo/metabolismo , Población Blanca/genética
5.
Clin Cancer Res ; 28(13): 2854-2864, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35522533

RESUMEN

PURPOSE: We designed a comprehensive multiple myeloma targeted sequencing panel to identify common genomic abnormalities in a single assay and validated it against known standards. EXPERIMENTAL DESIGN: The panel comprised 228 genes/exons for mutations, 6 regions for translocations, and 56 regions for copy number abnormalities (CNA). Toward panel validation, targeted sequencing was conducted on 233 patient samples and further validated using clinical FISH (translocations), multiplex ligation probe analysis (MLPA; CNAs), whole-genome sequencing (WGS; CNAs, mutations, translocations), or droplet digital PCR (ddPCR) of known standards (mutations). RESULTS: Canonical immunoglobulin heavy chain translocations were detected in 43.2% of patients by sequencing, and aligned with FISH except for 1 patient. CNAs determined by sequencing and MLPA for 22 regions were comparable in 103 samples and concordance between platforms was R2 = 0.969. Variant allele frequency (VAF) for 74 mutations were compared between sequencing and ddPCR with concordance of R2 = 0.9849. CONCLUSIONS: In summary, we have developed a targeted sequencing panel that is as robust or superior to FISH and WGS. This molecular panel is cost-effective, comprehensive, clinically actionable, and can be routinely deployed to assist risk stratification at diagnosis or posttreatment to guide sequencing of therapies.


Asunto(s)
Mieloma Múltiple , Variaciones en el Número de Copia de ADN , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/genética , Mutación , Translocación Genética , Secuenciación Completa del Genoma
6.
J Pharmacol Exp Ther ; 337(1): 187-200, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21228066

RESUMEN

Chronic nicotine treatment elicits a brain region-selective increase in the number of high-affinity agonist binding sites, a phenomenon termed up-regulation. Nicotine-induced up-regulation of α4ß2-nicotinic acetylcholine receptors (nAChRs) in cell cultures results from increased assembly and/or decreased degradation of nAChRs, leading to increased nAChR protein levels. To evaluate whether the increased binding in mouse brain results from an increase in nAChR subunit proteins, C57BL/6 mice were treated with nicotine by chronic intravenous infusion. Tissue sections were prepared, and binding of [(125)I]3-((2S)-azetidinylmethoxy)-5-iodo-pyridine (A85380) to ß2*-nAChR sites, [(125)I]monoclonal antibody (mAb) 299 to α4 nAChR subunits, and [(125)I]mAb 270 to ß2 nAChR subunits was determined by quantitative autoradiography. Chronic nicotine treatment dose-dependently increased binding of all three ligands. In regions that express α4ß2-nAChR almost exclusively, binding of all three ligands increased coordinately. However, in brain regions containing significant ß2*-nAChR without α4 subunits, relatively less increase in mAb 270 binding to ß2 subunits was observed. Signal intensity measured with the mAbs was lower than that with [(125)I]A85380, perhaps because the small ligand penetrated deeply into the sections, whereas the much larger mAbs encountered permeability barriers. Immunoprecipitation of [(125)I]epibatidine binding sites with mAb 270 in select regions of nicotine-treated mice was nearly quantitative, although somewhat less so with mAb 299, confirming that the mAbs effectively recognize their targets. The patterns of change measured using immunoprecipitation were comparable with those determined autoradiographically. Thus, increases in α4ß2*-nAChR binding sites after chronic nicotine treatment reflect increased nAChR protein.


Asunto(s)
Encéfalo/efectos de los fármacos , Nicotina/administración & dosificación , Agonistas Nicotínicos/metabolismo , Agonistas Nicotínicos/farmacología , Receptores Nicotínicos/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Animales , Sitios de Unión/efectos de los fármacos , Sitios de Unión/fisiología , Encéfalo/metabolismo , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Regulación hacia Arriba/fisiología
7.
FASEB J ; 24(1): 49-57, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19720621

RESUMEN

Recent studies suggest that high-affinity neuronal nicotinic acetylcholine receptors (nAChRs) containing alpha4 and beta2 subunits (alpha4beta2*) functionally interact with G-protein-coupled dopamine (DA) D(2) receptors in basal ganglia. We hypothesized that if a functional interaction between these receptors exists, then mice expressing an M2 point mutation (Leu9'Ala) rendering alpha4 nAChRs hypersensitive to ACh may exhibit altered sensitivity to a D(2)-receptor agonist. When challenged with the D(2)R agonist, quinpirole (0.5-10 mg/kg), Leu9'Ala mice, but not wild-type (WT) littermates, developed severe, reversible motor impairment characterized by rigidity, catalepsy, akinesia, and tremor. While striatal DA tissue content, baseline release, and quinpirole-induced DA depletion did not differ between Leu9'Ala and WT mice, quinpirole dramatically increased activity of cholinergic striatal interneurons only in mutant animals, as measured by increased c-Fos expression in choline acetyltransferase (ChAT)-positive interneurons. Highlighting the importance of the cholinergic system in this mouse model, inhibiting the effects of ACh by blocking muscarinic receptors, or by selectively activating hypersensitive nAChRs with nicotine, rescued motor symptoms. This novel mouse model mimics the imbalance between striatal DA/ACh function associated with severe motor impairment in disorders such as Parkinson's disease, and the data suggest that a D(2)R-alpha4*-nAChR functional interaction regulates cholinergic interneuron activity.


Asunto(s)
Trastornos Parkinsonianos/etiología , Receptores de Dopamina D2/metabolismo , Receptores Nicotínicos/fisiología , Acetilcolina/fisiología , Sustitución de Aminoácidos , Animales , Catalepsia/etiología , Fibras Colinérgicas/efectos de los fármacos , Fibras Colinérgicas/fisiología , Agonistas de Dopamina/farmacología , Epilepsia Generalizada/etiología , Femenino , Interneuronas/efectos de los fármacos , Interneuronas/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Rigidez Muscular/etiología , Mutagénesis Sitio-Dirigida , Trastornos Parkinsonianos/genética , Trastornos Parkinsonianos/fisiopatología , Quinpirol/farmacología , Receptores Nicotínicos/química , Receptores Nicotínicos/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temblor/etiología
8.
Nicotine Tob Res ; 13(8): 686-90, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21498873

RESUMEN

INTRODUCTION: Genetic effects contribute to individual differences in smoking behavior. Persistence to smoke despite known harmful health effects is mostly driven by nicotine addiction. As the physiological effects of nicotine are mediated by nicotinic acetylcholine receptors (nAChRs), we aimed at examining whether single nucleotide polymorphisms (SNPs) residing in nAChR subunit (CHRN) genes, other than CHRNA3/CHRNA5/CHRNB4 gene cluster previously showing association in our sample, are associated with smoking quantity or serum cotinine levels. METHODS: The study sample consisted of 485 Finnish adult daily smokers (age 30-75 years, 59% men) assessed for the number of cigarettes smoked per day (CPD) and serum cotinine level. We first studied SNPs residing on selected nAChR subunit genes (CHRNA2, CHRNA4, CHRNA6/CHRNB3, CHRNA7, CHRNA9, CHRNA10, CHRNB2, CHRNG/CHRND) genotyped within a genome-wide association study for single SNP and multiple SNP associations by ordinal regression. Next, we explored individual haplotype associations using sliding window technique. RESULTS: At one of the 8 loci studied, CHRNG/CHRND (chr2), single SNP (rs1190452), multiple SNP, and 2-SNP haplotype analyses (SNPs rs4973539-rs1190452) all showed statistically significant association with cotinine level. The median cotinine levels varied between the 2-SNP haplotypes from 220 ng/ml (AA haplotype) to 249 ng/ml (AG haplotype). We did not observe significant associations with CPD. CONCLUSIONS: These results provide further evidence that the γ-δ nAChR subunit gene region is associated with cotinine levels but not with the number of CPD, illustrating the usefulness of biomarkers in genetic analyses.


Asunto(s)
Frecuencia de los Genes/genética , Predisposición Genética a la Enfermedad/epidemiología , Polimorfismo de Nucleótido Simple/genética , Receptores Nicotínicos/genética , Fumar/genética , Tabaquismo/genética , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Finlandia/epidemiología , Estudio de Asociación del Genoma Completo , Haplotipos , Humanos , Desequilibrio de Ligamiento/genética , Masculino , Persona de Mediana Edad , Fumar/epidemiología , Tabaquismo/epidemiología
9.
Neurosci Lett ; 729: 134932, 2020 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-32224226

RESUMEN

The brain histaminergic and dopaminergic systems closely interact, and some evidence also suggests significant involvement of histamine in Parkinson's disease (PD), where dopaminergic neurons degenerate. To further investigate histamine-dopamine interactions, particularly in the context of PD, a genetic lack of histamine and a mouse model of PD and levodopa-induced dyskinesia were here combined. Dopaminergic lesions were induced in histidine decarboxylase knockout and wildtype mice by 6-hydroxydopamine injections into the medial forebrain bundle. Post-lesion motor dysfunction was studied by measuring drug-induced rotational behavior and dyskinesia. Striatal tissue from both lesioned and naïve animals was used to investigate dopaminergic, serotonergic and histaminergic biomarkers. Histamine deficiency increased amphetamine-induced rotation but did not affect levodopa-induced dyskinesia. qPCR measurements revealed increased striatal expression of D1 and D2 receptor, DARPP-32, and H3 receptor mRNA, and synaptosomal release experiments in naïve mice indicated increased dopamine release. A lack of histamine thus causes pre- and postsynaptic upregulation of striatal dopaminergic neurotransmission which may be reflected in post-lesion motor behavior. Disturbances or manipulations of the histaminergic system may thus have significant consequences for dopaminergic neurotransmission and motor behavior in both healthy and disease conditions. The findings also represent new evidence for the complex interplay between dopamine and histamine within the nigrostriatal pathway.


Asunto(s)
Neuronas Dopaminérgicas/metabolismo , Discinesia Inducida por Medicamentos/metabolismo , Levodopa/farmacología , Transmisión Sináptica/efectos de los fármacos , Animales , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Discinesia Inducida por Medicamentos/genética , Ratones , Oxidopamina/metabolismo , Enfermedad de Parkinson/metabolismo , Regulación hacia Arriba/efectos de los fármacos
10.
Eur J Pharm Sci ; 154: 105493, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32730846

RESUMEN

Toll-like receptor 4 (TLR4) recognizes various endogenous and microbial ligands and is an essential part in the innate immune system. TLR4 signaling initiates transcription factor NF-κB and production of proinflammatory cytokines. TLR4 contributes to the development or progression of various diseases including stroke, neuropathic pain, multiple sclerosis, rheumatoid arthritis and cancer, and better therapeutics are currently sought for these conditions. In this study, a library of 140 000 compounds was virtually screened and a resulting hit-list of 1000 compounds was tested using a cellular reporter system. The topoisomerase II inhibitor mitoxantrone and its analogues pixantrone and mitoxantrone (2-hydroxyethyl)piperazine were identified as inhibitors of TLR4 and NF-κB activation. Mitoxantrone was shown to bind directly to the TLR4, and pixantrone and mitoxantrone (2-hydroxyethyl)piperazine were shown to inhibit the production of proinflammatory cytokines such as tumor necrosis factor alpha (TNFα) in primary microglia. The inhibitory effect on NF-κB activation or on TNFα production was not mediated through cytotoxity at ≤ 1 µM concentration for pixantrone and mitoxantrone (2-hydroxyethyl)piperazine treated cells, as assessed by ATP counts. This study thus identifies a new mechanism of action for mitoxantrone, pixantrone, and mitoxantrone (2-hydroxyethyl)piperazine through the TLR4.


Asunto(s)
Isoquinolinas , FN-kappa B , Piperazina , Receptor Toll-Like 4 , Isoquinolinas/farmacología , Microglía , Mitoxantrona/farmacología , FN-kappa B/efectos de los fármacos , Piperazina/farmacología , Receptor Toll-Like 4/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
11.
Handb Exp Pharmacol ; (192): 85-112, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19184647

RESUMEN

The discovery that mammalian brain expresses the mRNAs for nine different nicotinic cholinergic receptor subunits (alpha2-alpha7, beta2-beta4) that form functional receptors when expressed in Xenopus laevis oocytes suggests that many different types of nicotinic cholinergic receptors (nAChRs) might be expressed in the mammalian brain., Using an historical approach, this chapter reviews some of the progress made in identifying the nAChR subtypes that seem to play a vital role in modulating dopaminergic function. nAChR subtypes that are expressed in dopamine neurons, as well as neurons that interact with dopamine neurons (glutamatergic, GABAergic), serve as the focus of this review. Subjects that are highlighted include the discovery of a low affinity alpha4beta2* nAChR, the identity of recently characterized alpha6* nAChRs, and the finding that these alpha6* receptors have the highest affinity for receptor activation of any of the native receptors that have been characterized to date. Topics that have been ignored in other recent reviews of this area, such as the discovery and potential importance of alternative transcripts, are presented along with a discussion of their potential importance.


Asunto(s)
Dopamina/metabolismo , Expresión Génica , Receptores Nicotínicos/metabolismo , Animales , Encéfalo/metabolismo , Humanos , Neuronas/metabolismo , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores Nicotínicos/genética
12.
Pharmacy (Basel) ; 7(1)2019 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-30813453

RESUMEN

The Pharmacy Education in Europe (PHARMINE) project studies pharmacy practice and education in the European Union (EU) member states. The work was carried out using an electronic survey sent to chosen pharmacy representatives. The surveys of the individual member states are now being published as reference documents for students and staff interested in research on pharmacy education in the EU, and in mobility. This paper presents the results of the PHARMINE survey on pharmacy practice and education in Finland. Pharmacies have a monopoly on the dispensation of medicines. They can also provide diagnostic services. Proviisori act as pharmacy owners and managers. They follow a five-year (M.Sc. Pharm.) degree course with a six-month traineeship. Farmaseutti, who follow a three-year (B.Sc. Pharm.) degree course (also with a six-month traineeship), can dispense medicines and counsel patients in Finland. The B.Sc. and the first three years of the M.Sc. involve the same course. The current pharmacy curriculum (revised in 2014) is based on five strands: (1) pharmacy as a multidisciplinary science with numerous opportunities in the working life, (2) basics of pharmaceutical sciences, (3) patient and medication, (4) optional studies and selected study paths, and (5) drug development and use. The learning outcomes of the pharmacy graduates include (1) basics of natural sciences: chemistry, physics, technology, biosciences required for all the students (B.Sc. and M.Sc.), (2) medicine and medication: compounding of medicines, holism of medication, pharmacology and biopharmaceutics (side-effects and interactions), patient counseling, efficacy and safety of medicines and medication, (3) comprehensive and supportive interactions of the various disciplines of pharmacy education and research: the role and significance of pharmacy as a discipline in society, the necessary skills and knowledge in scientific thinking and pharmaceutical research, and (4) basics of economics and management, multidisciplinarity, hospital pharmacy, scientific writing skills, management skills. In addition, teaching and learning of "general skills", such as the pharmacist's professional identity and the role in society as a part of the healthcare system, critical and creative thinking, problem-solving skills, personal learning skills and life-long learning, attitude and sense of responsibility, and communication skills are developed in direct association with subject-specific courses. Professional specialization studies in industrial pharmacy, and community and hospital pharmacy are given at the post-graduate level at the University of Helsinki.

13.
Neurosci Lett ; 672: 40-45, 2018 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-29474871

RESUMEN

The treatment of Parkinson's disease is often complicated by levodopa-induced dyskinesia (LID), and antidyskinetic treatment options are currently sparse. Nicotinic acetylcholine receptors have been suggested as potential targets for treatment of LID, as nicotinic agonists have been reported to alleviate LID in animal models. We aimed at the first independent replication of an antidyskinetic effect by nicotine using a mouse model of LID, and at investigation of its mechanisms by studying the release of [3H]dopamine from synaptosomes prepared from the dorsal and ventral striatum. Chronic nicotine treatment in drinking water inhibited the development of LID in mice lesioned unilaterally with 6-hydroxydopamine and treated chronically with levodopa and benserazide. The antidyskinetic nicotine treatment had no effect on [3H]dopamine release mediated by α4ß2* nicotinic receptors, but decreased α6ß2*-mediated [3H]dopamine release in the lesioned dorsal striatum and the ventral striatum. In addition, nicotine treatment restored [3H]dopamine release in the lesioned ventral striatum to intact levels. The results support a role for nicotinic receptors as drug targets for treatment of LID, and suggest that striatal presynaptic α6ß2* receptors are important mediators of nicotine's antidyskinetic effect.


Asunto(s)
Cuerpo Estriado/efectos de los fármacos , Dopamina/metabolismo , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Sinaptosomas/metabolismo , Animales , Cuerpo Estriado/metabolismo , Discinesia Inducida por Medicamentos/metabolismo , Levodopa/farmacología , Ratones , Nicotina/uso terapéutico , Agonistas Nicotínicos/uso terapéutico
14.
Neuropharmacology ; 138: 371-380, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29940207

RESUMEN

Preclinical studies suggest the involvement of various subtypes of nicotinic acetylcholine receptors in the pathophysiology of Parkinson's disease, a neurodegenerative disorder characterized by the death of dopaminergic neurons in the substantia nigra pars compacta (SNC). We studied for the first time the effects of α5 nicotinic receptor subunit gene deletion on motor behavior and neurodegeneration in mouse models of Parkinson's disease and levodopa-induced dyskinesia. Unilateral dopaminergic lesions were induced in wild-type and α5-KO mice by 6-hydroxydopamine injections into the striatum or the medial forebrain bundle. Subsequently, rotational behavior induced by dopaminergic drugs was measured. A subset of animals received chronic treatments with levodopa and nicotine to assess levodopa-induced dyskinesia and antidyskinetic effects by nicotine. SNC lesion extent was assessed with tyrosine hydroxylase immunohistochemistry and stereological cell counting. Effects of α5 gene deletion on the dopaminergic system were investigated by measuring ex vivo striatal dopamine transporter function and protein expression, dopamine and metabolite tissue concentrations and dopamine receptor mRNA expression. Hemiparkinsonian α5-KO mice exhibited attenuated rotational behavior after amphetamine injection and attenuated levodopa-induced dyskinesia. In the intrastriatal lesion model, dopaminergic cell loss in the medial cluster of the SNC was less severe in α5-KO mice. Decreased striatal dopamine uptake in α5-KO animals suggested reduced dopamine transporter function as a mechanism of attenuated neurotoxicity. Nicotine reduced dyskinesia severity in wild-type but not α5-KO mice. The attenuated dopaminergic neurodegeneration and motor dysfunction observed in hemiparkinsonian α5-KO mice suggests potential for α5 subunit-containing nicotinic receptors as a novel target in the treatment of Parkinson's disease.


Asunto(s)
Neuronas Dopaminérgicas/metabolismo , Actividad Motora/fisiología , Enfermedades Neurodegenerativas/metabolismo , Trastornos Parkinsonianos/metabolismo , Receptores Nicotínicos/deficiencia , Anfetamina/farmacología , Animales , Antiparkinsonianos/efectos adversos , Antiparkinsonianos/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Estimulantes del Sistema Nervioso Central/farmacología , Dopamina/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/patología , Discinesia Inducida por Medicamentos/metabolismo , Femenino , Lateralidad Funcional , Levodopa/efectos adversos , Levodopa/farmacología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Actividad Motora/efectos de los fármacos , Enfermedades Neurodegenerativas/patología , Oxidopamina , Trastornos Parkinsonianos/tratamiento farmacológico , Trastornos Parkinsonianos/patología , ARN Mensajero/metabolismo , Receptores Dopaminérgicos/metabolismo , Receptores Nicotínicos/genética
15.
Neuroscience ; 376: 188-203, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29374538

RESUMEN

Histamine H3 receptors are widely distributed Gi-coupled receptors whose activation reduces neuronal activity and inhibits release of numerous neurotransmitters. Although these receptors are abundantly expressed in the striatum, their modulatory role on activity-dependent dopamine release is not well understood. Here, we observed that histamine H3 receptor activation indirectly diminishes dopamine overflow in the ventral striatum by reducing cholinergic interneuron activity. Acute brain slices from C57BL/6 or channelrhodopsin-2-transfected DAT-cre mice were obtained, and dopamine transients evoked either electrically or optogenetically were measured by fast-scan cyclic voltammetry. The H3 agonist α-methylhistamine significantly reduced electrically- evoked dopamine overflow, an effect blocked by the nicotinic acetylcholine receptor antagonist dihydro-ß-erythroidine, suggesting involvement of cholinergic interneurons. None of the drug treatments targeting H3 receptors affected optogenetically evoked dopamine overflow, indicating that direct H3-modulation of dopaminergic axons is unlikely. Next, we used qPCR and confirmed the expression of histamine H3 receptor mRNA in cholinergic interneurons, both in ventral and dorsal striatum. Activation of H3 receptors by α-methylhistamine reduced spontaneous firing of cholinergic interneurons in the ventral, but not in the dorsal striatum. Resting membrane potential and number of spontaneous action potentials in ventral-striatal cholinergic interneurons were significantly reduced by α-methylhistamine. Acetylcholine release from isolated striatal synaptosomes, however, was not altered by α-methylhistamine. Together, these results indicate that histamine H3 receptors are important modulators of dopamine release, specifically in the ventral striatum, and that they do so by decreasing the firing rate of cholinergic neurons and, consequently, reducing cholinergic tone on dopaminergic axons.


Asunto(s)
Acetilcolina/metabolismo , Dopamina/metabolismo , Interneuronas/metabolismo , Receptores Histamínicos H3/metabolismo , Estriado Ventral/metabolismo , Animales , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Femenino , Agonistas de los Receptores Histamínicos/farmacología , Interneuronas/efectos de los fármacos , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Metilhistaminas/farmacología , Ratones Endogámicos C57BL , Ratones Transgénicos , Optogenética , ARN Mensajero/metabolismo , Sinaptosomas/metabolismo , Técnicas de Cultivo de Tejidos , Estriado Ventral/efectos de los fármacos
16.
Biochem Pharmacol ; 74(8): 1235-46, 2007 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-17825262

RESUMEN

This review summarizes studies that attempted to determine the subtypes of nicotinic acetylcholine receptors (nAChR) expressed in the dopaminergic nerve terminals in the mouse. A variety of experimental approaches has been necessary to reach current knowledge of these subtypes, including in situ hybridization, agonist and antagonist binding, function measured by neurotransmitter release from synaptosomal preparations, and immunoprecipitation by selective antibodies. Early developments that facilitated this effort include the radioactive labeling of selective binding agents, such as [(125)I]-alpha-bungarotoxin and [(3)H]-nicotine, advances in cloning the subunits, and expression and evaluation of function of combinations of subunits in Xenopus oocytes. The discovery of epibatidine and alpha-conotoxin MII (alpha-CtxMII), and the development of nAChR subunit null mutant mice have been invaluable in determining which nAChR subunits are important for expression and function in mice, as well as allowing validation of the specificity of subunit specific antibodies. These approaches have identified five nAChR subtypes of nAChR that are expressed on dopaminergic nerve terminals. Three of these contain the alpha6 subunit (alpha4alpha6beta2beta3, alpha6beta2beta3, alpha6beta2) and bind alpha-CtxMII with high affinity. One of these three subtypes (alpha4alpha6beta2beta3) also has the highest sensitivity to nicotine of any native nAChR that has been studied, to date. The two subtypes that do not have high affinity for alpha-CtxMII (alpha4beta2, alpha4alpha5beta2) are somewhat more numerous than the alpha6* subtypes, but do bind nicotine with high affinity. Given that our first studies detected readily measured differences in sensitivity to agonists and antagonists among these five nAChR subtypes, it seems likely that subtype selective compounds could be developed that would allow therapeutic manipulation of diverse nAChRs that have been implicated in a number of human conditions.


Asunto(s)
Cuerpo Estriado/química , Receptores Nicotínicos/clasificación , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Bungarotoxinas/metabolismo , Conotoxinas/metabolismo , Conotoxinas/farmacología , Dopamina/metabolismo , Ratones , Piridinas/metabolismo , Receptores Nicotínicos/análisis
17.
Pharmacy (Basel) ; 5(2)2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28970441

RESUMEN

In order to meet the expectations to act as an expert in the health care profession, it is of utmost importance that pharmacy education creates knowledge and skills needed in today's working life. Thus, the planning of the curriculum should be based on relevant and up-to-date learning outcomes. In the University of Helsinki, a university wide curriculum reform called 'the Big Wheel' was launched in 2015. After the reform, the basic degrees of the university are two-cycle (Bachelor-Master) and competence-based, where the learning outcomes form a solid basis for the curriculum goals and implementation. In the Faculty of Pharmacy, this curriculum reform was conducted in two phases during 2012-2016. The construction of the curriculum was based on the most relevant learning outcomes concerning working life via high quality first (Bachelor of Science in Pharmacy) and second (Master of Science in Pharmacy) cycle degree programs. The reform was kicked off by interviewing all the relevant stakeholders: students, teachers, and pharmacists/experts in all the working life sectors of pharmacy. Based on these interviews, the intended learning outcomes of the Pharmacy degree programs were defined including both subject/contents-related and generic skills. The curriculum design was based on the principles of constructive alignment and new structures and methods were applied in order to foster the implementation of the learning outcomes. During the process, it became evident that a competence-based curriculum can be created only in close co-operation with the stakeholders, including teachers and students. Well-structured and facilitated co-operation amongst the teachers enabled the development of many new and innovative teaching practices. The European Union funded PHAR-QA project provided, at the same time, a highly relevant framework to compare the curriculum development in Helsinki against Europe-wide definitions of competences and learning outcomes in pharmacy education.

18.
J Comp Neurol ; 499(6): 1016-38, 2006 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-17072836

RESUMEN

Immunolabeling of beta2 and alpha4 subunits was quantitated in brain sections (14 mum) using [(125)I]mAb 270 and [(125)I]mAb 299, respectively. Specificity was demonstrated by signal loss in beta2(-/-) and alpha4(-/-) brain sections, respectively. Even mild paraformaldehyde fixation severely affected immunolabeling, so this study used unfixed sections. Immunolabeling autoradiography was used to map and quantitate the effects of beta2 and alpha4 subunit-null mutations on their putative partner subunits' protein expression. [(125)I]mAb 299 labeling was nearly eliminated in beta2(-/-) sections, although dorsal interpeduncular nucleus (IPN) retained a faint signal. Therefore, alpha4 subunit expression is almost universally beta2-dependent. In contrast, alpha4-null mutation effects on [(125)I]mAb 270 immunolabeling varied widely among brain regions. In corticothalamic regions, [(125)I]mAb 270 labeling was eliminated. However, in habenulopeduncular regions, alpha4 genotype had no effect. Other (predominantly dopaminergic and optic tract) nuclei also retained reduced [(125)I]mAb 270 labeling in alpha4(-/-) sections. Thus, although most beta2 subunit protein expression is alpha4-dependent, this dependence is not universal. Presumably, residual beta2 subunits are found in non-alpha4* subtypes. Together, these results show that immunolabeling is applicable to reliable, quantitative investigations of neuronal nAChRs, and that subunit-null mutants can be appropriate controls for such experiments. In situ mRNA hybridization was also performed to determine if altered mRNA transcription mediated the interdependence of alpha4 and beta2 subunit expression. alpha4-Null mutation did not affect beta2 mRNA expression, nor did beta2 genotype affect alpha4 mRNA expression. Consequently, it seems that the two subunits' effects on each other's expression are mediated at the protein, rather than gene expression level.


Asunto(s)
Química Encefálica/fisiología , Encéfalo/metabolismo , Inmunohistoquímica/métodos , Mutación/genética , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Acetilcolina/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Autorradiografía/métodos , Encéfalo/anatomía & histología , Femenino , Radioisótopos de Yodo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Ensayo de Unión Radioligante , Transmisión Sináptica/fisiología
19.
J Neurosci ; 23(35): 11045-53, 2003 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-14657161

RESUMEN

Nigrostriatal dopaminergic neurons express many nicotinic acetylcholine receptor (nAChR) subunits capable of forming multiple nAChR subtypes. These subtypes are expressed differentially along the neuron and presumably mediate diverse responses. beta3 subunit mRNA has restricted expression but is abundant in the substantia nigra and ventral tegmental areas. To investigate the potential role(s) of nicotinic receptors containing the beta3 subunit in dopaminergic tracts, we generated mice with a null mutation in the beta3 gene. We were thereby able to identify a population of beta3-dependent alpha-conotoxin MII-binding nAChRs that modulate striatal dopamine release. Changes were also observed in locomotor activity and prepulse inhibition of acoustic startle, behaviors that are controlled, in part, by nigrostriatal and mesolimbic dopaminergic activity, respectively, suggesting that beta3-containing nAChRs modulate these behaviors.


Asunto(s)
Conotoxinas/metabolismo , Dopamina/metabolismo , Receptores Nicotínicos/metabolismo , Animales , Conducta Animal/fisiología , Unión Competitiva , Cuerpo Estriado/química , Cuerpo Estriado/citología , Cuerpo Estriado/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Marcación de Gen , Hibridación in Situ , Ligandos , Masculino , Ratones , Ratones Noqueados , Ratones Mutantes , Actividad Motora/genética , Inhibición Neural/efectos de los fármacos , Nicotina/farmacología , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , ARN Mensajero/metabolismo , Ratas , Receptores Nicotínicos/genética , Reflejo de Sobresalto/genética , Sustancia Negra/química , Sustancia Negra/citología , Sustancia Negra/metabolismo , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo
20.
Neuropharmacology ; 48(5): 696-705, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15814104

RESUMEN

The subunit composition and pharmacology of alpha-Conotoxin MII-binding (alpha-CtxMII) nicotinic acetylcholine receptors (nAChR) was studied by an improved [(125)I]-alpha-CtxMII membrane binding method. This binding method facilitates pharmacological studies that have been difficult to accomplish with [(125)I]-alpha-CtxMII autoradiography or alpha-CtxMII inhibition of [(125)I]-epibatidine binding. Binding densities and K(d)-values obtained by this [(125)I]-alpha-CtxMII membrane binding were similar to the values obtained by autoradiography or alpha-CtxMII inhibition of [(125)I]-epibatidine binding, verifying that each of these approaches measures the same nAChR population. Binding results with nAChR subunit-null mutant mice confirm and extend observations from earlier studies: [(125)I]-alpha-CtxMII binding measures two sets of alpha6beta2* nAChR (alpha4alpha6beta2beta3 or alpha6beta2beta3). Most nicotinic agonists and antagonists show monophasic inhibition of [(125)I]-alpha-CtxMII binding, indicating that alpha4alpha6beta2beta3 and alpha6beta2beta3 have similar binding properties. Comparison of the binding and activation profiles of alpha6beta2* nAChR to those of other nAChR subtypes (alpha4beta2* and beta4*) indicates that these receptors have distinctly different pharmacology indicating that it may be possible to target alpha6beta2* nAChR selectively to develop compounds that might be therapeutically useful.


Asunto(s)
Membrana Celular/efectos de los fármacos , Conotoxinas/farmacología , Antagonistas Nicotínicos/farmacología , Receptores Nicotínicos/efectos de los fármacos , Acetilcolina/farmacología , Alcaloides/farmacología , Animales , Azetidinas/farmacología , Azocinas/farmacología , Unión Competitiva/efectos de los fármacos , Encéfalo/anatomía & histología , Encéfalo/efectos de los fármacos , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacocinética , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Concentración de Iones de Hidrógeno , Isótopos de Yodo/farmacocinética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Nicotina/farmacología , Agonistas Nicotínicos/farmacocinética , Unión Proteica/efectos de los fármacos , Subunidades de Proteína/genética , Piridinas/farmacocinética , Quinolizinas/farmacología , Ensayo de Unión Radioligante/métodos , Receptores Nicotínicos/genética , Factores de Tiempo
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