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1.
Int J Tuberc Lung Dis ; 26(8): 775-783, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35898124

RESUMO

BACKGROUND: TB caused by rifampicin-resistant (RR) and multidrug-resistant (MDR) Mycobacterium tuberculosis strains is a major concern to TB control globally. However, in the European Union, MDR-TB notifications among all bacteriologically confirmed TB cases with available drug susceptibility testing (DST) results decreased over the last years.METHODS: We conducted a retrospective analysis on DST results reported from 2011 to 2020 by 46 laboratories in 19 out of 20 regions in Italy in order to evaluate resistance trends to first- and second-line drugs in MDR/RR-TB strains isolated from Italian-born persons (IBPs) and foreign-born persons (FBPs).RESULTS: Of 23,972 M. tuberculosis strains examined (15,519 from FBPs and 8,453 from IBPs), MDR-TB decreased from 3.2% in 2011 to 2.2% in 2020. High MDR/RR-TB rates occurred mostly in FBPs from former Soviet Union countries. In 2017, a MDR/RR-TB increase was detected in FBPs from sub-Saharan Africa. MDR-TB strains showed consistent increase in resistance to pyrazinamide (PZA), slight increase in resistance to fluoroquinolones and a decrease in resistance to other drugs.CONCLUSION: While MDR/RR-TB cases slightly decreased, a worrisome increase of resistance to PZA and fluoroquinolones among MDR/RR-TB patients was seen. This implies that a fast and efficient diagnosis aligned with therapy is crucial for TB control.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Fluoroquinolonas/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Rifampina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
2.
Int J Tuberc Lung Dis ; 25(5): 395-399, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33977908

RESUMO

BACKGROUND: Treatment outcomes in multidrug-resistant TB (MDR-TB) patients are suboptimal in several low-incidence countries.METHODS: The primary outcome measure was the proportion of successfully treated patients in Italy during an 18-year period. Secondary outcomes were treatment outcomes in certain drug-containing regimens and the possibility for the WHO shorter MDR-TB regimen.RESULTS: In the 191 patients included (median age at admission: 33 years; 67.5% male, following drug-resistance patterns were found: MDR-TB in 68.6%, pre-extensively drug-resistant TB (pre-XDR-TB) in 30.4% and XDR-TB in 1.1% patients. The most frequently prescribed drugs were fluoroquinolones in 84.6% cases, amikacin in 48.7%, linezolid in 34.6% and meropenem/clavulanic acid in 29.5%. The median duration of treatment was 18 months. Treatment success was achieved in 71.2% patients, of whom, 44% were cured and 27.2% completed treatment. Treatment success rates did not statistically differ between the MDR- (68.8%) and pre-XDR-TB (77.6%) groups (P = 0.26). Treatment success rates had large variability between North and South of Italy (81.3% vs. 53.3%). Only 22.5% of the cases would have been eligible for shorter MDR-TB regimensCONCLUSION: Our study highlights variability in treatment outcomes in MDR- and pre-XDR-TB patients. Study findings confirmed the potential utility of linezolid and, for patients with limited oral options, meropenem/clavulanic acid and amikacin.


Assuntos
Tuberculose Extensivamente Resistente a Medicamentos , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/uso terapêutico , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Tuberculose Extensivamente Resistente a Medicamentos/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
3.
Cell Mol Immunol ; 18(3): 711-722, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32728200

RESUMO

In cancer, myeloid cells have tumor-supporting roles. We reported that the protein GPNMB (glycoprotein nonmetastatic B) was profoundly upregulated in macrophages interacting with tumor cells. Here, using mouse tumor models, we show that macrophage-derived soluble GPNMB increases tumor growth and metastasis in Gpnmb-mutant mice (DBA/2J). GPNMB triggers in the cancer cells the formation of self-renewing spheroids, which are characterized by the expression of cancer stem cell markers, prolonged cell survival and increased tumor-forming ability. Through the CD44 receptor, GPNMB mechanistically activates tumor cells to express the cytokine IL-33 and its receptor IL-1R1L. We also determined that recombinant IL-33 binding to IL-1R1L is sufficient to induce tumor spheroid formation with features of cancer stem cells. Overall, our results reveal a new paracrine axis, GPNMB and IL-33, which is activated during the cross talk of macrophages with tumor cells and eventually promotes cancer cell survival, the expansion of cancer stem cells and the acquisition of a metastatic phenotype.


Assuntos
Fibrossarcoma/patologia , Receptores de Hialuronatos/metabolismo , Interleucina-33/metabolismo , Neoplasias Pulmonares/patologia , Macrófagos/imunologia , Glicoproteínas de Membrana/metabolismo , Células-Tronco Neoplásicas/patologia , Animais , Apoptose , Proliferação de Células , Fibrossarcoma/etiologia , Fibrossarcoma/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Receptores de Hialuronatos/genética , Interleucina-33/genética , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos DBA , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/metabolismo , Sarcoma Experimental/etiologia , Sarcoma Experimental/metabolismo , Sarcoma Experimental/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
BMC Psychol ; 8(1): 63, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539837

RESUMO

BACKGROUND: Sexting has recently emerged as a public health and social issue. The present study had two aims: a) to preliminarily test adolescent gender differences on parental practices regarding adolescent online life, parental monitoring, adolescent attitude towards sexting and sexting behaviors; b) to separately test for male and female adolescents a conceptual model in which sexting behaviors are explained by the parental practices and monitoring, with the mediation of adolescent negative attitude towards sexting. METHODS: Direct and indirect links between the variables in the model were investigated. The study was carried out with 541 participants. Participants were Italian adolescents (60% males; 40% females) aged 14 to 19 years (Mage = 16,19 years, SDage = 1,31). RESULTS: Results suggested that females sent more multimedia sexts, had a higher perception of risk associated with sexting and reported higher scores for both parental practices regarding adolescent online life and parental monitoring. Rules on Contents, Parental Knowledge, Adolescent Disclosure, and Parental Control resulted to be linked to both sexting attitudes and behaviors for male and female adolescents. CONCLUSIONS: Findings emphasize the important role that parents play in shaping attitudes and behaviors of both daughters and sons during adolescence.


Assuntos
Comportamento do Adolescente , Poder Familiar , Comportamento Sexual , Envio de Mensagens de Texto , Adolescente , Adulto , Atitude , Feminino , Humanos , Itália , Masculino , Relações Pais-Filho , Fatores Sexuais , Adulto Jovem
6.
Growth Horm IGF Res ; 21(5): 292-303, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21865068

RESUMO

OBJECTIVE: Due to its potent neurotrophic activity, insulin-like growth factor I (IGF-I) has been proposed many times for therapeutic application in disorders of the central nervous system (CNS). However, insufficient brain delivery to yield beneficial central without peripheral side effects have prevented clinical development in most instances. DESIGN: We recently reported the generation of a polyethylene-glycol modified IGF-I variant (PEG-IGF-I) with prolonged half-life and less acute side effects, but with fully maintained slow anabolic activity. Here we investigated if these beneficial properties result in improved brain availability of the drug, thereby reaching therapeutically relevant steady-state concentrations to elicit beneficial effects on neuronal function. RESULTS: After a single subcutaneous injection, PEG-IGF-I reached much higher steady-state levels in brain tissue and cerebrospinal fluid compared with IGF-I. Two weeks treatment with PEG-IGF-I was sufficient to modulate brain plasticity processes, as judged by changes in synaptic proteins and related animal behavior. Furthermore, chronic treatment of a mouse model of brain amyloidosis with PEG-IGF-I reverted deficits in insulin/IGF-I signaling, synaptic proteins and cognitive performance. CONCLUSIONS: Our data generate the therapeutic potential for PEG-IGF-I to treat CNS disorders by systemic drug application, and in addition scientifically support its application in disorders of synaptic function and neuronal development.


Assuntos
Fator de Crescimento Insulin-Like I/análogos & derivados , Fármacos Neuroprotetores/farmacocinética , Polietilenoglicóis/farmacocinética , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Química Encefálica , Doenças do Sistema Nervoso Central/tratamento farmacológico , Fator de Crescimento Insulin-Like I/administração & dosagem , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like I/líquido cefalorraquidiano , Fator de Crescimento Insulin-Like I/química , Fator de Crescimento Insulin-Like I/farmacocinética , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/análise , Fármacos Neuroprotetores/farmacologia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/análise , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Ratos , Ratos Wistar , Fatores de Tempo
8.
Br J Pharmacol ; 156(8): 1326-41, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19751316

RESUMO

BACKGROUND AND PURPOSE: The OX(2) receptor is a G-protein-coupled receptor that is abundantly found in the tuberomammillary nucleus, an important site for the regulation of the sleep-wake state. Herein, we describe the in vitro and in vivo properties of a selective OX(2) receptor antagonist, N-ethyl-2-[(6-methoxy-pyridin-3-yl)-(toluene-2-sulphonyl)-amino]-N-pyridin-3-ylmethyl-acetamide (EMPA). EXPERIMENTAL APPROACH: The affinity of [(3)H]EMPA was assessed in membranes from HEK293-hOX(2)-cells using saturation and binding kinetics. The antagonist properties of EMPA were determined by Schild analysis using the orexin-A- or orexin-B-induced accumulation of [(3)H]inositol phosphates (IP). Quantitative autoradiography was used to determine the distribution and abundance of OX(2) receptors in rat brain. The in vivo activity of EMPA was assessed by reversal of [Ala(11),D-Leu(15)]orexin-B-induced hyperlocomotion during the resting phase in mice and the reduction of spontaneous locomotor activity (LMA) during the active phase in rats. KEY RESULTS: [(3)H]EMPA bound to human and rat OX(2)-HEK293 membranes with K(D) values of 1.1 and 1.4 nmol x L(-1) respectively. EMPA competitively antagonized orexin-A- and orexin-B-evoked accumulation of [(3)H]IP at hOX(2) receptors with pA(2) values of 8.6 and 8.8 respectively. Autoradiography of rat brain confirmed the selectivity of [(3)H]EMPA for OX(2) receptors. EMPA significantly reversed [Ala(11),D-Leu(15)]orexin-B-induced hyperlocomotion dose-dependently during the resting phase in mice. EMPA, injected i.p. in rats during the active phase, reduced LMA dose-dependently. EMPA did not impair performance of rats in the rotarod procedure. CONCLUSIONS AND IMPLICATIONS: EMPA is a high-affinity, reversible and selective OX(2) receptor antagonist, active in vivo, which should prove useful for analysis of OX(2) receptor function.


Assuntos
Aminopiridinas/farmacologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores de Neuropeptídeos/antagonistas & inibidores , Sulfonamidas/farmacologia , Administração Oral , Aminopiridinas/administração & dosagem , Aminopiridinas/metabolismo , Aminopiridinas/farmacocinética , Animais , Autorradiografia , Sítios de Ligação , Ligação Competitiva , Encéfalo/metabolismo , Células CHO , Sinalização do Cálcio/efeitos dos fármacos , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Humanos , Injeções Intraperitoneais , Fosfatos de Inositol/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Cinética , Masculino , Camundongos , Neuropeptídeos/metabolismo , Receptores de Orexina , Orexinas , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo , Sulfonamidas/administração & dosagem , Sulfonamidas/metabolismo , Sulfonamidas/farmacocinética , Transfecção
9.
Int J Immunopathol Pharmacol ; 21(2): 401-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18547485

RESUMO

Immune reactivity towards the bacterial intestinal flora plays an important part in the pathogenesis of inflammatory bowel disease. Administration of probiotic bacteria has beneficial effects on infectious and inflammatory diseases, principally in bowel disorders. However, little is known about the administration of soluble bacterial antigens in intestinal inflammation. We investigated the therapeutic effects of colifagina in experimental colitis. To assess this effect, C57BL/6 mice with dextran sulphate sodium-induced colitis were treated with colifagina, or with a placebo, for a period of 10 days. The mice were monitored, and inflammation was assessed by disease activity index (DAI). Analysis of fecal IgA concentration and measurement of IgA and inflammatory chemokine production in organ colonic culture was performed by ELISA. Clinically and histologically, bacterial-lysate-treated mice revealed significantly fewer DAI and a reduction of colonic histological inflammation. Treatment of healthy mice with colifagina significantly increased the fecal concentration of IgA and IgA production in organ culture. Colifagina administration in DSS-treated mice significantly increased the fecal concentration of IgA and IgA production in organ culture. MIP-1, MIP-2 and RANTES concentrations in colonic organ culture were significantly lower in colifagina-treated mice than in the placebo group. The use of colifagina is effective in amelioration of murine colitis.


Assuntos
Colite/tratamento farmacológico , Probióticos/uso terapêutico , Animais , Quimiocinas/antagonistas & inibidores , Quimiocinas/biossíntese , Colite/induzido quimicamente , Colite/patologia , Colo/patologia , Fezes/microbiologia , Imunoglobulina A/imunologia , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos
10.
Pharmacogenomics J ; 8(3): 196-208, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17684478

RESUMO

Dysregulation of the endocannabinoid system is known to interfere with emotional processing of stressful events. Here, we studied the role of cannabinoid receptor type 1 (CB1) signaling in stress-coping behaviors using the forced swim test (FST) with repeated exposures. We compared effects of genetic inactivation with pharmacological blockade of CB1 receptors both in male and female mice. In addition, we investigated potential interactions of the endocannabinoid system with monoaminergic and neurotrophin systems of the brain. Naive CB1 receptor-deficient mice (CB1-/-) showed increased passive stress-coping behaviors as compared to wild-type littermates (CB1+/+) in the FST, independent of sex. These findings were partially reproduced in C57BL/6N animals and fully reproduced in female CB1+/+ mice by pharmacological blockade of CB1 receptors with the CB1 receptor antagonist SR141716. The specificity of SR141716 was confirmed in female CB1-/- mice, where it failed to affect behavioral performance. Sensitivity to the antidepressants desipramine and paroxetine was preserved, but slightly altered in female CB1-/- mice. There were no genotype differences between CB1+/+ and CB1-/- mice in monoamine oxidase A and B activities under basal conditions, nor in monoamine content of hippocampal tissue after FST exposure. mRNA expression of vesicular glutamate transporter type 1 was unaffected in CB1-/- mice, but mRNA expression of brain-derived neurotrophic factor (BDNF) was reduced in the hippocampus. Our results suggest that impaired CB1 receptor function promotes passive stress-coping behavior, which, at least in part, might relate to alterations in BDNF function.


Assuntos
Adaptação Psicológica , Receptor CB1 de Canabinoide/fisiologia , Transdução de Sinais/fisiologia , Estresse Psicológico/psicologia , Animais , Monoaminas Biogênicas/análise , Fator Neurotrófico Derivado do Encéfalo/genética , Desipramina/farmacologia , Feminino , Hipocampo/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monoaminoxidase/metabolismo , Piperidinas/farmacologia , Pirazóis/farmacologia , RNA Mensageiro/análise , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/genética , Rimonabanto , Natação , Proteína Vesicular 1 de Transporte de Glutamato/genética
11.
Biochem Soc Trans ; 34(Pt 6): 1014-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17073740

RESUMO

Other than signalling receptors sustaining leucocyte recruitment during inflammatory reactions, the chemokine system includes 'silent' receptors with distinct specificity and tissue distribution. The best-characterized molecule of this subgroup is the CC chemokine receptor D6, which binds most inflammatory CC chemokines and targets them to degradation via constitutive ligand-independent internalization. Structure-function analysis and recent results with gene-targeted animals indicate that D6 has unique functional and structural features, which make it ideally adapted to act as a chemokine decoy and scavenger receptor, strategically located on lymphatic endothelium and placenta to dampen inflammation in tissues and draining lymph nodes.


Assuntos
Inflamação/fisiopatologia , Leucócitos/fisiologia , Receptores de Quimiocinas/fisiologia , Humanos , Ligantes , Vasos Linfáticos/fisiologia , Modelos Biológicos , Receptores CCR10 , Receptores de Interleucina-1/fisiologia , Receptor D6 de Quimiocina
12.
Auton Neurosci ; 90(1-2): 102-5, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11485275

RESUMO

The analysis of heart rate variability (HRV) provides information about autonomic cardiovascular control in healthy subjects. In the past 15 years, several articles have been published regarding HRV and chronic heart failure (CHF). The results of these papers substantially demonstrated that HRV is significantly different in CHF patients compared to controls. Moreover, some variables derived from HRV analysis showed significant independent prognostic capacity. In particular, the reduction of variance (expressed as SDNN) and low-frequency spectral component of HRV (ranging from 0.03 to 0.15 Hz) seem related to an increased mortality in CHF. Nevertheless, these variables are not yet considered in clinical practice. A better understanding of the physiopathological basis of the reported alterations of HRV in CHF patients is required in order to permit its use as a clinical tool for prognosis and tailored therapy in individual CHF patients.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca/fisiologia , Sistema Nervoso Simpático/fisiopatologia , Doença Crônica , Humanos
14.
Chemistry ; 6(6): 971-82, 2000 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-10785817

RESUMO

The enzyme catechol O-methyltransferase (COMT) catalyzes the Me group transfer from the cofactor S-adenosylmethionine (SAM) to the hydroxy group of catechol substrates. Potential bisubstrate inhibitors of COMT were developed by structure-based design and synthesized. The compounds were tested for in vitro inhibitory activity against COMT obtained from rat liver, and the inhibition kinetics were examined with regard to the binding sites of cofactor and substrate. One of the designed molecules was found to be a bisubstrate inhibitor of COMT with an IC50 = 2 microM. It exhibits competitive kinetics for the SAM and noncompetitive kinetics for the catechol binding site. Useful structure-activity relationships were established which provide important guidelines for the design of future generations of bisubstrate inhibitors of COMT.


Assuntos
Inibidores de Catecol O-Metiltransferase , Inibidores Enzimáticos/síntese química , Animais , Sítios de Ligação , Catecóis/metabolismo , Catecóis/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Cinética , Fígado/enzimologia , Modelos Moleculares , Doença de Parkinson/tratamento farmacológico , Ratos , S-Adenosilmetionina/análogos & derivados , S-Adenosilmetionina/metabolismo
17.
J Neural Transm Suppl ; 52: 173-87, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9564618

RESUMO

The present report reviews recent advances in mapping the cellular sites of synthesis and catalytic activity, as well as age- and disease-related changes of monoamine oxidases A and B in the brain. A transgenic model of oxidative stress is also described. The relevance of these findings for the physiological and pathophysiological roles of monoamine oxidases is briefly discussed.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Monoaminoxidase/metabolismo , Doença de Alzheimer/enzimologia , Animais , Encéfalo/enzimologia , Encéfalo/fisiopatologia , Radicais Livres/metabolismo , Humanos , Isoenzimas/metabolismo , Camundongos , Camundongos Transgênicos , Monoaminoxidase/genética , Estresse Oxidativo , Doença de Parkinson/enzimologia , Ratos
18.
Behav Brain Res ; 73(1-2): 245-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8788511

RESUMO

The purpose of the present study was to determine whether the 5-ht6 receptor is functionally expressed in the rat brain by blocking its translation from mRNA with treatments of phosphorothioate antisense oligonucleotides. Rats were treated with either saline, antisense (AO) or scrambled oligonucleotides (SO) for 4 days. Treatment with AO reduced the number of [3H]LSD binding sites in the frontal lobes by 30% but had no significant effect on the number of 5-HT1A and 5-HT2A receptor binding sites in the cortex of the rats. A behavioural syndrome of yawning, stretching and chewing, however, was observed in AO treated rats but not in any of the other treatment groups. This AO-specific behaviour had returned to normal 5 days after cessation of the oligodeoxynucleotide treatment. These data suggest that the 5-ht6 receptor has a physiological function in the rat brain where it appears to be under the tonic control of endogenous 5-HT.


Assuntos
Oligonucleotídeos Antissenso/farmacologia , Receptores de Serotonina/biossíntese , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacocinética , Animais , Sequência de Bases , Comportamento Animal/efeitos dos fármacos , Ligação Competitiva/efeitos dos fármacos , Técnicas In Vitro , Injeções Intraventriculares , Ketanserina/farmacocinética , Dietilamida do Ácido Lisérgico/farmacocinética , Masculino , Membranas/efeitos dos fármacos , Membranas/metabolismo , Dados de Sequência Molecular , Oligonucleotídeos Antissenso/administração & dosagem , Ratos , Ratos Endogâmicos , Receptores de Serotonina/fisiologia , Antagonistas da Serotonina/farmacocinética , Agonistas do Receptor de Serotonina/farmacocinética
19.
J Pharmacol Exp Ther ; 274(1): 173-80, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7616396

RESUMO

The purpose of the present study was to determine possible physiological functions of the 5-ht6 receptor using antisense oligonucleotides (AOs) in male rats. Repeated intracerebroventricular treatment with AOs but not with a scrambled form of the antisense sequence (SO) gave rise to a specific behavioral syndrome of yawning, stretching and chewing and caused a 30% reduction in the number of [3H]-lysergic acid diethylamide binding sites (measured in the presence of 300 nM spiperone). Neither sequence, however, had any effect on other parameters measured (e.g., locomotor activity, body weight, food intake, body temperature and nociception). The specific behavioral syndrome did not appear to be caused by modulation of dopaminergic neurotransmission since no changes in the tissue levels of either dopamine or its metabolites 3,4-dihydroxyphenylacetic acid and homovanillic acid were seen. Furthermore, haloperidol (0.03 mg/kg s.c.) did not reduce the number of yawns or stretches. An increase in cholinergic neurotransmission did appear to be involved since the behavioral syndrome was dose-dependently antagonized by atropine. The present study suggests that 5-ht6 receptors are functionally expressed in the rat brain, where one of their functions appears to be the control of cholinergic neurotransmission.


Assuntos
Encéfalo/fisiologia , Oligonucleotídeos Antissenso , Receptores de Serotonina/fisiologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Atropina/farmacologia , Sequência de Bases , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopamina/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Haloperidol/farmacologia , Masculino , Dados de Sequência Molecular , Atividade Motora/efeitos dos fármacos , Ratos , Receptores de Serotonina/efeitos dos fármacos
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